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Location of the plant is South India,
Plant stem looks like Banana.
It is Fishtail Palm, Example picture look like this:
A gore, gore point, or gore zone is a triangular piece of land found where roads or rivers merge or split. When two roads merge, the area is sometimes referred to as a merge nose.
Gores on freeways in the United States and Canada are frequently marked with stripes or chevrons at both entrance and exit ramps.
- the term is more commonly used among "insiders," such as road construction crews, police, traffic engineers, and so on. (Wikipedia)
- a triangular tract of land, especially one lying between larger divisions. (Random House Dictionary).
On the East Coast (US) it is often colloquially referred to as "the zebra stripes":
There is a disabled car on the zebra stripes by Exit 5.
From an engineering point of view, definitely, that is not a gore (because a gore has a physical front and is an object) but in AASHTO it is referred as "neutral area".
Image on page 874 from, A policy on Geometric Design of Highways and Streets by AASHTO, 2001.
Image FOR Illustration fhwa.dot.gov/publications/research/safety/07045/inp.cfm
MANUAL: AASHTO American Association of State Highway and Transportation Officials A Policy on Geometric Design of Highways and Streets, Page 10-96
On page 32 of this PDF prepared for the California Department of Transportation the term used is "Hatch Striping".
In the UK we call them hatched area or chevron marked area: see pages 62-66 of this official guide
It is a triangle patch of land you do not drive in. While this may not be technical, I've never heard a driving instructor, peace officer, or court refer to this patch as a gore (road). It's pretty short for a road, which is probably why we don't drive in it.
In addition, does this usage apply anywhere else besides the place the Wikipedia author lives, ie, I mean, seriously, like in (other) English-speaking countries?
If it is a technical term, as used within an industry, discipline, profession, or field of study, I as a layman reserve the right to use non-technical terms.
noun a triangular or tapering piece of material used in making a garment, sail, or umbrella.
ORIGIN Old English gāra ‘triangular piece of land,’ of Germanic origin related to Dutch geer and German Gehre, also probably to Old English gār ‘spear’ (a spearhead being triangular).
Fleabane (Erigeron philadelphicus) blooms March to August in moist soils in fields, pastures, woodland edges, roadsides, and along streams throughout the eastern half of Texas. Prairie fleabane (Erigeron modestus) blooms March through November in gravelly or rocky calcareous soils in open areas and hillsides in North Central and western Texas. Photo: R.W. Smith
Texas spiderlily (Hymenocallis liriosme) blooms March to May and prefers swampy or other moist bottomland, banks of streams, and ditches along the Gulf Coast and in East Texas. The plant can grow 40 inches tall. The elegant varietal gets its genus name from the Greek kallos, meaning “beautiful,” and hymen, which means “membrane. Photo: Joseph A. Marcus
Spiderwort (Tradescantia spp.) blooms statewide February through June. Spiderworts were named for John Tradescant the Elder (1570-1638) and John Tradescant the Younger (1608-62), both of whom were English royal gardeners. The Tradescants grew plants sent to them and collected by them in America. As a result, spiderworts are common in English gardens. Photo: Tim Fitzharris
Standing Cypress (Ipomopsis rubra) blooms in May, June, and July in central and east Texas. The first year of growth produces a “ferny rosette” followed by a “flower spike” the second year, according to the Lady Bird Johnson Wildflower Center. Photo: Will van Overbeek
Mountain pink (Centaurium beyrichii) thrives on the barren, gravel-strewn hills of Central Texas and westward. The flowers, which bloom May through August, branch to form a nearly perfect bouquet. Called quinine weed by pioneers, the plants were dried and used to reduce fevers. Photo: Joseph A. Marcus
Butterfly weed (Asclepias tuberosa) blooms April to September throughout Texas in fields, thickets, open woodlands, and hillsides. The densely packed flowers, rich in nectar, attract bees, beelike flies, and butterflies. Photo: Ray Mathews
Blackfoot daisy (Melampodium leucanthum) blooms early spring through fall, thriving on calcareous soils of West and Central Texas. The low-growing perennial’s blooms form a dense, compact mound. Other common Texas daisies are Tahoka daisy (Machaeranthera tanacetifolia), huisache daisy (Amblyolepis setigera), chocolate daisy (Berlandiera lyrata), and sleepy daisy (Xanthisma texanum). Photo Courtesy Lady Bird Johnson Wildflower Center: Lee Page
Spotted beebalm (Monarda punctata) blooms May through August. This tall erect annual or biennial thrives in sandy or rocky pastures, prairies, plains, and meadows throughout Texas. Also called lemon-mint, horsemint, and wild bergamot, the genus was named in honor of Spanish writer and physician Nicolás Monardes (1493-1588), whose work introduced much of Europe to such American plants as balsam, coca, corn, passionflower, potatoes, sarsaparilla, sunflower, and tobacco. Photo: Steven Schwartzman
Brown-eyed Susan (Rudbeckia hirta) blooms May through September and is a prairie species found throughout the state. Renowned Swedish naturalist Carl Linnaeus (1707-78) dedicated the genus to two of his predecessors at the University of Uppsala, Olaus and Olof Rudbeck. Hirta means “rough” or “hairy” in Latin. Photo: Sean Fitzgerald
Beach morning glory
Beach morning glory (Ipomoea imperati) blooms April through December on Gulf Coast dunes and beaches. Roots are important in helping to stabilize the dunes. This white morning glory frequently grows with the rosy and purple goat-foot morning glory (Ipomoea pes-caprae), which also helps stabilize coastal dunes. Photo: Alan Cressler
Texas bluebell (Eustoma exaltatum) blooms June to September in moist areas in fields and prairies, and in drainage areas, except in the Big Bend region. Bluebells have virtually disappeared in many locations because of indiscriminate picking. One of the state’s loveliest flowers, an entire field is stunning. Flowers range from bluish-purple to white, or white with tinges of yellow or purple. It’s sometimes called prairie gentian and lira de San Pedro (Saint Peter’s lyre). Photo: Sean Fitzgerald
List of Plant Hormones
This hormone is present in the seed embryo, young leaves, and apical buds’ meristem.
- Stimulation of cell elongation, cell division in cambium, differentiation of phloem and xylem, root initiation on stem cuttings, lateral root development in tissue culture
- Delaying leaf senescence
- Suppression of lateral bud growth when supplied from apical buds
- Inhibition or promotion of fruit and leaf abscission through ethylene stimulation
- Fruit setting and growth induced through auxin in some plants
- Auxin can delay fruit ripening
- In Bromeliads, the auxin hormone promotes flowering
- Stimulation of flower parts, femaleness of dioecious flowers, and production of high concentration of ethylene in flowering plants
They are synthesized in roots and then transported to other parts of the plant.
Functions of Cytokinins
- Stimulation of cell division, growth of lateral buds, and apical dominance
- Stimulation of shoot initiation and bud formation in tissue culture
- Leaf cell enlargement that stimulates leaf expansion
- Enhancement of stomatal opening in some plant species
- Etioplasts converted into chloroplasts through stimulation of chlorophyll synthesis.
Ethylene is present in the tissues of ripening fruits, nodes of stems, senescent leaves, and flowers.
Functions of Ethylene
- Leads to release of dormancy state
- Stimulates shoot and root growth along with differentiation
- Leaf and fruit abscission
- Flower induction in Bromeliad
- Stimulation of femaleness of dioecious flowers
- Flower opening is stimulated
- Flower and leaf senescence stimulation
- Stimulation of Fruit ripening
Abscisic acid is found mostly near leaves, stems, and unripe fruit.
Would you like to write for us? Well, we're looking for good writers who want to spread the word. Get in touch with us and we'll talk.
Functions of Abscisic Acid
- Stimulation of closing of stomata
- Inhibition of shoot growth
- Inducing seeds for synthesizing storage of proteins
Gibberellins are present in the meristems of apical buds and roots, young leaves, and embryo.
Functions of Gibberellins
- Stimulates stem elongation
- Leads to development of seedless fruits
- Delays senescence in leaves and citrus fruits
- Ends seed dormancy in plants that require light for induction of germination
The cells in a plant are the most basic units of life that come together to form its different parts such as the leaves, stems, roots etc. These plant parts,&hellip
Plant growth is the process by which the plant grows in size. A matured plant has a strong stem and healthy leaves. The growth process is enhanced by the nutrients&hellip
Plant cells have always spurred curiosity amongst biology students, besides others. Hence, here in this article, I have provided some detailed information.
Several reports indicate a postfire flush of Scotch broom germination from the soil seed bank [17,85,97,138]. Several studies also indicate increased germination of Scotch broom seeds following heat treatments in the laboratory [14,107,121,130]. These results suggest that seeds of this species are well adapted to postfire germination.
Fire regimes: There is no information available on the fire regimes in which the brooms evolved in their native range. However, Scotch broom and Genista florida, a close relative of French broom, were early successional species following fire in their native range in Spain .
It is unclear how the presence of brooms may affect fire regimes in invaded communities. In general, in ecosystems where broom replaces plants similar to itself (in terms of fuel characteristics), brooms may alter fire intensity or slightly modify an existing fire regime. However, if broom invasion introduces novel fuel properties to the invaded ecosystem, they have the potential to alter fire behavior and potentially alter the fire regime (sensu [20,31]). A review of Scotch broom in Australia  suggests that presence of Scotch broom creates a fire hazard in forest areas in Australia and California, although the source of this assertion is not given. Where Scotch broom invades subalpine eucalypt woodland in Australia it forms a dense shrub layer, overtopping and depleting the grass layer, thus altering fuel structure such that fire intensities fueled by shrubs in the invaded community would likely be higher than those fueled by grasses in an uninvaded community . Scotch broom invasions are also said to increase fire intensity and frequency in invaded Oregon white oak communities [23,138]. According to Tveten , where Scotch broom has invaded prairie and Oregon white oak woodlands on Fort Lewis in western Washington, it forms dense stands and increases fire hazard by creating extensive areas with large amounts of dead wood.
Scotch broom and striated broom occur in a variety of ecosystems in North America that represent a range of historic fire regimes. In many areas where brooms occur, historic fire regimes have been dramatically altered due to fire exclusion and to massive disturbances associated with human settlement. The historic fire regimes of native communities in which brooms sometimes occur range from high frequency fires in grasslands to high frequency, low-severity fires in open ponderosa pine forests and moderate frequency, high-severity fires in California chaparral. Brooms did not occur in these communities at a time when historic fire regimes were functioning, but has established since fire exclusion and habitat alteration began. It is unclear how historic fire regimes might affect broom populations.
It is also unclear how the use of fire to control broom in these communities might impact native species. Plant adaptations to fire are usually to a particular fire regime, or combination of fire frequency, intensity, extent, and season. When fire is used to control nonnative species, the frequency, intensity, and season of burning must be carefully chosen to avoid damaging native species. Prescribed fire may have undesirable effects if introduced into an ecosystem that has undergone shifts in species composition, structure, and fuel characteristics outside a natural range of variability in these attributes . When the natural fire regime is altered, even highly fire-adapted plant communities may be vulnerable to competition from nonnative species .
According to Swezy and Odion , fire is an effective management tool for French broom, but is used primarily in mixed evergreen forest and grassland communities in California, where repeated annual burning for broom control "appears to have no unwanted side effects." Prescribed fire is used less frequently in chaparral communities where frequent burning or burning outside the natural fire season may have adverse effects on native communities.
Herbaceous communities dominated by nonnative annual grasses and forbs of Mediterranean origin occur throughout the Coast Ranges and foothills of the Cascade Range and the Sierra Nevada. A review by Keeley  indicates that much of the nonnative annual grassland in the Coast Ranges of central and southern California derives from a fire-induced type conversion of shrublands. The herbaceous communities that have long dominated these landscapes were largely created by anthropogenic burning by Native Americans, and were further maintained by intensive land use with fire and livestock grazing by European-Americans. In recent decades, however, grazing has been eliminated in some areas and anthropogenic fires reduced such that woody vegetation is reestablishing. Along with native shrubs, nonnative shrubs such as Scotch broom, French broom, and gorse colonize these sites. Nonnative shrub colonization of grasslands may decrease fire frequency but increase fuel loads and alter fire behavior ( and references therein).
In the Puget Trough of Washington and adjacent parts of British Columbia, native plant communities were once a mosaic of Oregon oak woodlands, wetlands, and fescue prairies. This mosaic is said to have been maintained by Native Americans who used fire to maintain conditions favorable to the growth of common camas and bracken fern (Pteridium aquilinum). These frequent fires removed shrubs and killed small Oregon oaks and Douglas-fir, maintaining a low density of woody species. A plethora of impacts following in the wake of Euro-American settlement, including fire suppression, grazing by livestock, introduction of nonnative species, landscape fragmentation, recreation, and other management impacts, have changed the structure and composition of these plant communities ([23,107,144] and references therein). Exclusion of fire from these communities has changed the regeneration pathways of Oregon white oak and increased densities of Douglas-fir, ponderosa pine, and understory shrubs. The natural vegetation associations of Oregon white oak are threatened by these interrelated conditions . Scotch broom has become an important nonnative species in Oregon white oak habitats. It forms dense canopies 3 to 9 feet (1-3 m) tall, interfering with native species. Altered fuel structure and increased fuel loading result from invasion of Scotch broom and other nonnative species such as colonial bentgrass [23,134,137].
The relationship of Oregon white oak communities and fire is critical to any restoration effort . If fire is used to reduce the occurrence and spread of Scotch broom in these ecosystems, consideration must be given to presettlement fire regime characteristics. Oak woodlands and associated prairies evolved with frequent, low-severity surface fires . "Seasonal burning" in lowland prairies in Washington reportedly discourages Scotch broom invasion . Spring burning on a 3- to 5-year rotation in Weir Prairie, Washington, causes little change in native prairie vegetation and maintains open Oregon white oak stands. Conversely, 50 years of annual burning in one area has eliminated Scotch broom and restricted Douglas-fir establishment, but has changed the native perennial bunchgrass prairies to introduced forb and annual grassland. On the other hand, fire suppression is more harmful to prairie vegetation than excessive burning, allowing Douglas-fir and Scotch broom to invade prairies and Oregon white oak woodlands. Closed stands of these species eliminate nearly all native prairie species. Sampled plots indicate that no native prairie species remained after 12 years of closed Scotch broom cover. Fall burning is recommended to remove Douglas-fir and Scotch broom from heavily infested areas, along with follow-up fires to kill dense Scotch broom postfire seedling establishment .
Reintroducing fire to these communities as a means of rehabilitation and restoration is complicated by the increased fuel loads associated with long-term fire exclusion and nonnative species invasion. On oak-prairie margins, fire used to control Scotch broom can pose risks to oaks unless it is used frequently enough to prevent excessive accretion of fuel . High fire severities associated with high fuel loads increase mortality of Oregon white oak seedlings and saplings. Thysell and Carey  describe areas at Fort Lewis where mature oaks appear to have been killed by severe fire that was fueled by Scotch broom. Mechanical removal of Scotch broom and Douglas-fir before burning may reduce the potential for negative effects on oaks [23,134,137].
A single intense fire can reduce Scotch broom cover, but is likely to encourage germination of Scotch broom from the seed bank [17,85,97,138] and at least temporarily reduce cover of native perennials such as Idaho fescue. A second fire is necessary to kill broom seedlings within 2 to 3 years, before Scotch broom seedlings are reproductively mature (see Fire Management Considerations) . Many native plants in these native communities thrive after a single low-severity fire, but may be adversely affected by repeated burning . Additionally, nonnative species may be favored over native species if fire is too frequent [23,137]. Spot treatments using a flame thrower in the winter, when grasses are green and fire will not spread, can remove residual Scotch broom plants missed in previous fire treatments .
A prescribed fire program has been used to manage prairies and oak woodlands in some areas of Fort Lewis since the 1960s and 1970s. Fires are mostly set in February and March, and occasionally in the fall, on a 3 to 5 year rotation. The primary objective of the program is fuel reduction. While the program has been successful at maintaining some of the "best prairie and Oregon white oak woodland vegetation in western Washington," it has not completely stopped prairie encroachment by Douglas-fir and Scotch broom. Spring fires often fail to burn under dense Scotch broom or young Douglas-fir. So whenever possible, heavily invaded areas are burned under drier conditions than are open prairies. Even under drier conditions, however, spring fires often fail to burn through stands of dense Scotch broom or young Douglas-fir, leaving clusters of these species to reinvade burned areas .
The complex relationships among oak woodlands, wetlands, prairies, Douglas-fir forests, introduced nonnative plants, and intensively developed urban, suburban, and agricultural areas suggest that both a comprehensive set of conservation objectives and a comprehensive assessment of techniques for promoting indigenous species and techniques for controlling nonnative species are needed .
The following list provides fire return intervals for plant communities and ecosystems where Scotch and/or striated broom may be important. It may not be inclusive. Find further fire regime information for the plant communities in which these species may occur by entering the species' names in the FEIS home page under "Find Fire Regimes".
POSTFIRE REGENERATION STRATEGY :
Small shrub, adventitious bud/root crown
Ground residual colonizer (on-site, initial community)
What's The Next Big Thing?
(This program is no longer available for online streaming.) In this episode of NOVA scienceNOW, come face to face with social robots that understand human feelings, carry on conversations, even make jokes. Then travel to Haiti, where geologists investigate the 2010 earthquake not long after it struck for clues to how to better forecast future quakes. Afterwards, join engineers at General Motors who are testing tiny, two-wheeled cars called EN-Vs, which one day might drive themselves through city streets. Learn about proposals for making our outdated electric grid "smart." And meet Nebraska native Jay Keasling, a pioneer in synthetic biology who shares his work on developing "designer" microbes that produce biofuels and medicines.
More Ways to Watch
What's The Next Big Thing?
PBS Airdate: February 23, 2011
NEIL DEGRASSE TYSON: (Astrophysicist, American Museum of Natural History) : Hi, I'm Neil deGrasse Tyson, your host of NOVA scienceNOW, where this season we're asking six big questions. On this episode, What Is The Next Big Thing?
NEIL DEGRASSE TYSON: They can be cute.
MAYA CAKMAK: Simon, can you hear me?
SIMON THE ROBOT: Loud and clear.
NEIL DEGRASSE TYSON: . friendly.
PHILIP K. DICK ROBOT: Chad, let's chat.
NEIL DEGRASSE TYSON: . and even convenient.
CHARLES KEMP (Georgia Institute of Technology) : Robots have a lot of potential to enhance somebody's life.
NEIL DEGRASSE TYSON: They're social robots.
NEIL DEGRASSE TYSON: . specially designed, so we will like them.
CHAD COHEN: When he turns and looks at you, you feel it!
WOMAN: He's much better looking than I thought!
SHERRY TURKLE (Massachusetts Institute of Technology) : We feel as though there's somebody home, but, in fact, there's nobody home.
NEIL DEGRASSE TYSON: Could machines that fit in with humans become dangerous?
DAVID HANSON (Hanson Robotics) : As soon as you have true, deep intelligence in a machine, it will be very difficult to contain.
NEIL DEGRASSE TYSON: And could the next big thing be "the big one,".
WOMAN'S VOICE (Haitian Earthquake Survivor): The world is coming to an end.
NEIL DEGRASSE TYSON: . like the earthquake that devastated Haiti in 2010. These researchers saw it coming, but how accurate was their forecast?
THOMAS H. JORDAN (Southern California Earthquake Center) : We're playing a statistical game, and, frankly, nature has the odds.
NEIL DEGRASSE TYSON: And could California be next?
Also, are you in a jam? Could your traffic prayers be answered, by this?
ZIYA TONG (Correspondent) : Let's go for a cruise!
NEIL DEGRASSE TYSON: Not only is it tiny, you won't have to worry about this happening. These little cars sense danger and stop on their own. Are automated cars about to take away your license to drive?
CHRISTOPHER BORRONI-BIRD (General Motors) : It will come and pick me up.
ZIYA TONG: This is so much cooler than valet. I love it.
NEIL DEGRASSE TYSON: All that.
ROBOT: . and more, on this episode of NOVA scienceNOW!
NEIL DEGRASSE TYSON: When we imagine the future and high-tech solutions to all our problems, one of the first things that comes to mind is the robot: a computer-driven machine that tirelessly fulfills our every need. But some engineers imagine a day when robots will be much more than our assistants.
ROBOT: Hey, Neil, what are you doing?
NEIL DEGRASSE TYSON: I'm going to work.
NEIL DEGRASSE TYSON: They'll also be our friends.
Correspondent Chad Cohen found some robots being built, not just to work for us, but to care about our feelings and make us care about them.
ROBOT: Hey, Neil, don't forget your briefcase.
NEIL DEGRASSE TYSON: Thank you.
CHAD COHEN: For me, this is the ultimate in robots: C3PO, the loyal protocol droid in Star Wars . R2D2 may tug at our heartstrings, but a robot that looks and acts human and can perform our tasks, that's something.
C3PO ( Star Wars /Film Clip) : Now, don't you forget this.
CHAD COHEN: That's something. And today, a revolution is booting up around the world, to build robots just like us.
Engineers, scientists, even artists are developing robots to take over what have forever been uniquely human tasks. Like Herb, the robot butler and Snackbot.
SNACKBOT ROBOT: I have your order here.
CHAD COHEN: . the android delivery boy and Nannybot, the robot babysitter.
In Japan, where the aging population is growing faster than in any other country, researchers are developing robots to care for the elderly. Robots like these seem destined to become part of our everyday life, if can we make them act less like machines and more like us.
MAYA CAKMAK: Simon, can you hear me?
SIMON THE ROBOT: Loud and clear. Can you hear me?
CHAD COHEN: Here at the Georgia Institute of Technology, roboticists Andrea Thomaz and her graduate students.
MAYA CAKMAK Simon, take this.
CHAD COHEN: . are striving to create a kinder, gentler-looking robot, one with a touch of grace.
SIMON THE ROBOT: Let me take a closer look.
CHAD COHEN: . and a face that's easy to love.
ANDREA THOMAZ (Georgia Institute of Technology) : We wanted the robot to have a friendly, childlike look, so that people are not afraid to interact with it.
RODNEY BROOKS (Massachusetts Institute of Technology) : One of the things that robots can do is give social cues of what their intent is. So a humanoid robot looking over where it's about to reach, that gives a person a good feeling that they know what the robot is going to do.
MAYA CAKMAK: Yes, Simon, that's correct. You have learned a task.
CHAD COHEN: If we are comfortable with Simon, the theory goes, it will be easier for us to welcome and incorporate him into our lives.
SIMON THE ROBOT: That was fun.
CHAD COHEN: Roboticist David Hanson agrees. But he's not just making robots that look and act friendly, at his home-slash-laboratory outside of Dallas, he's humanizing machines on a whole new level.
DAVID HANSON: Iɽ like to introduce you to Phil.
PHILIP K. DICK ROBOT: Hi, nice to see you.
CHAD COHEN: That is so bizarre.
This is Philip K. Dick. Well, actually it's a robot David fashioned after his favorite sci-fi author. Dick, who died in 1982, wrote the story that inspired the cult classic Blade Runner , in which robots and humans are indistinguishable.
This resurrected Philip isn't quite there yet. All he can do is move his head. His brain? A mesh of wires connected to a computer.
Hi, Philip. My name is Chad.
PHILIP K. DICK ROBOT: Hello, Chad. Let's chat.
CHAD COHEN: I live in Washington, D.C. I have two kids.
PHILIP K. DICK ROBOT: Ah, um, so, I like kids ⟊use we can play.
CHAD COHEN: As we chat, Philip's synthetic brain starts humming, building a sort of mental model of me. Facial recognition software analyzes and tracks my face, as speech recognition software transcribes and sends my words to a database for a reply.
Before long we're in deep conversation.
Do you agree with Descartes' "I think therefore I am?" Do you "think?"
PHILIP K. DICK ROBOT: A lot of humans ask me if I can make choices or if everything I do and say is programmed. The best way I can respond to that is to say that everything humans, animals and robots do is programmed, to a degree.
CHAD COHEN: So, how much of that is coming from what you've programmed it to say?
DAVID HANSON: It's a mix. Some of it's coming from knowledge on the Web, some of it is written.
PHILIP K. DICK ROBOT: As my technology improves, it is anticipated that I will be able to integrate new words that I hear and learn online and in real time. I may not get everything right, say the wrong thing and sometimes not know what to say, but every day I make progress. Pretty remarkable, huh?
You're a very good looking man.
PHILIP K. DICK ROBOT: Um, you're starting to over-inflate my ego, but don't let me stop you.
CHAD COHEN: Philip's stunning good looks comes from David's patented formula for synthetic skin. Colleague Bill Hicks demonstrates.
BILL HICKS (HANSON ROBOTICS?): We've come up with a beautiful, unique recipe for simulating human skin. This is a lot like a cooking recipe.
CHAD COHEN: A combination of chemicals and a little bit of color are put into a mold. Several hours later, voila.
BILL HICKS: We're ready to go.
DAVID HANSON: The Frubber has the right properties, that will allow it to fold and to bunch, to crease and move into these forms that, uh, that we think of as expressions.
CHAD COHEN: David then attaches the skin to tiny motors.
So, little motors inside pull on the Frubber, basically, on the skin?
CHAD COHEN: To get, kind of, like, a suite of human facial features, how many motors do you need?
DAVID HANSON: Um, 28 motors, for all the major muscles.
DAVID HANSON: . in the face.
So, you can see in the forehead, some of the brow action.
CHAD COHEN: That is just crazy messed up.
I mean, it's amazing, It's amazing to look at. Because you sit there and he's got the facial expressions, and he sits there like he's engaged in the conversation. When he turns and looks at you and locks eyes, you feel it. And he definitely says things that make you empathetic to him in some way. You feel like, "Oh, he's aware."
And that's exactly what some experts worry about. Not that Phillip is aware, but that I'm so easily tricked into believing he is.
SHERRY TURKLE: We're very cheap dates. We have Darwinian buttons, like being looked in the eye or being tracked. Once you have that kind of creature doing that to you, our buttons are pressed, and we feel as though there's somebody home, but, in fact, there's nobody home.
CHAD COHEN: Already, between internet chats and texting, we're constantly interacting with technology. Robots could take this trend one giant step further as they start doing jobs that have always been considered intrinsically human.
SHERRY TURKLE: If you give a nannybot, a babysitting robot, to your child, how are you going to explain why you couldn't find a person? "Not enough people on the globe, we've decided to do a robot."
Or to your mother, "Not enough people, certainly not me a robot."
DAVID HANSON: I don't buy the idea that we're developing robots so we don't have to take care of our own. I think that there will be unpredictable consequences, not all positive, but, for the most part, what we are developing could be very positive.
CHAD COHEN: Back at Georgia Tech, researchers Wendy Rogers and Charles Kemp couldn't agree more. They're testing robots where they think they'll be needed most, with the older generation.
CHARLIE KEMP: Instead of you having to worry about what time it is and, "Should I be taking medicine," imagine if the robot were just to come up to you and say, "Here. You just need to take this."
MAN: Thank you, that's quite impressive.
WENDY ROGERS (Georgia Institute of Technology) : Could you imagine having a robot like this in your home, and, if so, what kind of tasks would you want it to do for you?
WOMAN: Oh, like the Jetsons I want it to vacuum and answer the phone, answer the door and do all the futuristic stuff.
WOMAN: . come and clean my house anytime it wants. Love it, teach it to iron. And, in fact, he's much better looking than I thought heɽ be.
I have a friend who is looking for a dancing partner? Seriously. Can he come to a party?
SHERRY TURKLE: My problem with sociable robots is that we begin to think about the sociable and lose track of the robots. We're setting ourselves up for disappointment, because these robots will disappoint us if we are looking for human connection. Do we want to make them in such a way that we're going to love them because they will be pretending to love us?
CHAD COHEN: David fears, if we don't humanize robots by bringing them into the human family, we face a frightening future.
Think Terminator—a world in which killer robots turn on their creators and set out to destroy us.
ARNOLD SCHWARZENEGGER (As the Terminator/ The Terminator /Film Clip) : Hasta la vista, baby!
CHAD COHEN: Do you think robots will take over the world?
PHILIP K. DICK ROBOT: Jeez, dude. You all got the big questions cooking today. But you're my friend, and I'll remember my friends, and I will be good to you. So don't worry. Even if I evolve into Terminator, I will still be nice to you. I will keep you warm and safe in my people zoo, where I can watch you for old time's sake.
CHAD COHEN: I'm comforted, I'm very comforted now. I'm going to be part of his people zoo.
In the future, will people fall in love with robots?
Seems like a lot of songwriters already have.
We found at least 44 songs about people in love with robots.
I'M IN LOVE WITH A ROBOT GIRL
I FELL IN LOVE WITH AN ANDROID
I FELL IN LOVE WITH A ROBOT
FELL IN LOVE WITH A ROBOT MAID
MY BOYFRIEND'S IN LOVE WITH A ROBOT
I'M IN LOVE WITH THE TERMINATOR
Next big thing: an album in the works?
NEIL DEGRASSE TYSON: Even with all our technology and the inventions that make modern life so much easier than it once was, it takes just one big natural disaster to wipe all that away and remind us that, here on Earth, we're still at the mercy of nature.
We don't know how to stop these natural disasters. Thanks to technology, we're getting better at seeing them coming, but some approaching disasters aren't visible from the sky. Catastrophic earthquakes, capable of wiping out entire cities, are driven by forces deep underground. If only we could peer beneath the surface and see what's coming.
Correspondent Kirk Wolfinger takes us to some tectonic hot spots, where researchers are inventing new tools to try and detect killer quakes before they strike.
KIRK WOLFINGER (Correspondent) : This is what Port-au-Prince, the capital of Haiti, looked like, on January 11, 2010.
WOMAN'S VOICE: The world is coming to an end!
KIRK WOLFINGER: And this was the same city, 24 hours later.
JEAN ROBERT JOSEPH ( Haitian Earthquake Survivor): Everybody was calling, "Jesus, Jesus, Jesus!"
KIRK WOLFINGER: The city was flattened by a massive earthquake, measuring 7.0. More than 230,000 people died. A quarter of a million buildings were reduced to rubble.
THOMAS JORDAN: The Haiti earthquake of January 12th is the fifth largest killing earthquake in history.
KIRK WOLFINGER: But it was not unexpected.
ERIC CALAIS: There was a police station there. Can't see anything, and that's because there's nothing left.
KIRK WOLFINGER: But almost two years before the quake, geophysicist Eric Calais saw this coming. Along with his colleagues at the Haitian Bureau of Mines, they actually forecast this earthquake with amazing accuracy.
DIEUSEUL ANGLADE (Haiti Bureau of Mines and Energy) : With the University of Purdue, we calculated the magnitude of the, of the earthquake, and we have found 7.2. And we, we knew that this earthquake will be very, very catastrophic.
KIRK WOLFINGER: They did it by measuring Earth's movements along the Enriquillo fault zone. The Enriquillo fault, a giant crack in the Earth's surface , runs the entire length of Haiti.
If you could peer underground, youɽ see a complex jumble of jagged fissures where pieces of the Earth's crust rub up against each other. The two sides of the fault drift in opposite directions.
Eric's team set out to measure the speed of the two moving plates. In 2003, they placed six steel pins in key locations on both sides of the fault.
ERIC CALAIS: It's a piece of metal, stainless steel, that we sealed in the. at the top of this building.
KIRK WOLFINGER: On top of each pin, Eric attached a G.P.S. antenna, linked to a satellite 12,500 miles up.
The global positioning system can detect even the tiniest movements of the pins, showing Eric that the two sides of the fault are moving about a quarter of an inch away from each other, every year.
It doesn't sound like much, but it makes a big difference, because the two sides don't slide smoothly. Friction keeps the rocks locked together and tension builds up.
ERIC CALAIS: What we saw was a fault being loaded just like a rubber band.
KIRK WOLFINGER: Eventually, the rubber band snaps. The result is an earthquake.
But how powerful would the earthquake be? Eric did a simple calculation: the speed of the two plates, a quarter inch, or seven millimeters, per year, times the number of years since the last, known, big earthquake: 250.
ERIC CALAIS: Seven times 250 is about 1.8 meters, so there's 1.8 meters of motion that could be released.
KIRK WOLFINGER: In 2008, Eric forecast an earthquake of magnitude 7.2. It was tragically accurate. All that was lacking was a timeframe.
ERIC CALAIS: It's not that we were afraid to put a date on it, it's that as a scientist, we can't.
KIRK WOLFINGER: The timing of some natural disasters is predictable. For example, a hurricane's path can be seen and measured. Its time of landfall can usually be predicted to within an hour. But earthquake scientists are at a huge disadvantage. The powerful forces they study are hidden from view, deep underground.
ERIC CALAIS: The core of the problem is at depth. Fifteen kilometers, roughly speaking, that's the place where we would like to be making our measurements. I would give up my G.P.S. instruments and my surface measurements, if only I could have measurement of the forces inside the earth.
KIRK WOLFINGER: And that's what they're trying to do at another earthquake hotspot, thousands of miles away.
Having witnessed the devastation in Haiti, I've come to a place with some geological similarities a place where the risk of a major quake is just as great if not greater. In California, Ernie Majer and his team are placing instruments deep inside the Earth, where the seismic forces that cause earthquakes are born.
ERNEST MAJER (Lawrence Berkeley National Laboratory) : And we have a seismic source, and then we have a seismic receiver, and.
KIRK WOLFINGER: Source and receiver?
ERNIE MAJER: A source and a receiver.
KIRK WOLFINGER: The tubes are placed in holes dug deep into the rock: 3,000 feet deep. Now, why 3,000 feet?
ERNIE MAJER: Well, that's as deep as we could get.
KIRK WOLFINGER: Imagine trying to see 3,000 feet, a half a mile, underground. That's nine of the towers behind me, stacked one on top of the other, drilled into solid rock.
ERNIE MAJER: So, all right, hear that little, "Pop, pop, pop, pop?" So, that vibration goes out through the Earth, and this oscilloscope, here.
ERNIE MAJER: . is, is measuring the signal.
KIRK WOLFINGER: In 2005 and 2006, while measuring stress along California's San Andreas Fault, Ernie's team got a reading that caught them by surprise. The audio pulses suddenly began to speed up. This happened just before a magnitude 3 earthquake.
ERNIE MAJER: The change started about 10 hours beforehand.
KIRK WOLFINGER: This could be something people have sought for centuries: an earthquake warning sign, a way to predict when an earthquake is about to happen.
So, have you been able to be consistent with this?
ERNIE MAJER: We hope to replicate this over the next year or so. We might be on the path for prediction. We don't know that yet.
ERIC CALAIS: Earthquake prediction, to some extent, is the Holy Grail of the whole field.
KIRK WOLFINGER: And nowhere are they searching harder for the Holy Grail than here, in California.
It's riddled with active geological faults, the most infamous being the San Andreas, which runs the length of the state and is one of the most studied faults in the world.
Tom Jordan coordinates 600 scientists to produce an incredibly detailed, comprehensive earthquake forecast for California that maps out which communities are most at risk.
THOMAS JORDAN: It uses the historical information, it uses our mapping of faults, our understanding of the physics of earthquakes, to estimate how frequently earthquakes will occur in California, where they're going to occur, how big they're going to be, and something about, you know, the probabilities in a given time period.
KIRK WOLFINGER: The result of all that research is this animated computer simulation. It shows in graphic and terrifying detail, how tremors would spread from a rupture on the San Andreas Fault, and move across Southern California.
THOMAS JORDAN: The earthquake has just begun down here, in the southern end of the fault. And it's propagating up the fault at about 6,000 miles per hour.
Notice how it turns and goes into the Los Angeles region. This is an area that's filled with very soft sediments, and it conducts the energy very well.
KIRK WOLFINGER: The simulation shows which neighborhoods are most at risk.
I'm standing here, in the Hollywood Hills, just above the city of Los Angeles. In that simulated earthquake there would be a shockwave that would go right by where I'm standing, and it would shake for about 20 seconds. That would be bad, but because I am on bedrock, I'm probably okay.
THOMAS JORDAN: About 80 seconds after the event began, the strong shaking begins in Los Angeles.
KIRK WOLFINGER: Below the hills, the flatlands will be hit hardest. This whole area sits on sediment, and there will be an aftershake that lasts for several minutes. And that's where the damage will come. And, as you can see, there is a lot here to be damaged.
The 30-year forecast gives a 94 percent probability of California being hit by a quake as big as the one that hit Port-au-Prince.
THOMAS JORDAN: We just have to be prepared for that inevitability.
KIRK WOLFINGER: And it is inevitable, it's not.
THOMAS JORDAN: It is inevitable. It is going to happen. Now, when it happens, we cannot say.
KIRK WOLFINGER: We're still looking for the Holy Grail: predicting the exact timing of an earthquake. But our ability to forecast their size and location is already good and getting better.
Armed with these long-term forecasts, people in earthquake-prone areas can take steps to prepare for the inevitable, the next big one.
THOMAS JORDAN: Are you going to take your chances and hope you luck out, or do you invest for the worst? We're playing a statistical game. It's a gambler's game, and, frankly, nature has the odds.
. and an internet connection?
Want to help scientists measure and report earthquakes around the world?
Well, then join the "Quake-Catcher Network!"
It uses the built-in motion sensor in your laptop.
. along with lots of others.
Together they can sense and report earthquakes as small as 2.6 on the Richter scale.
NEIL DEGRASSE TYSON: We all know it's dangerous to drive and do other stuff at the same time. Well, cars of the future might fix that. Correspondent Ziya Tong ran down some folks designing robotic cars that could make driving a whole lot safer because we won't be behind the wheel.
ZIYA TONG: Driving today is a nightmare. From texting drivers to horrific traffic jams, the car, once our biggest convenience, is creating some of our biggest problems.
CHRIS BORRONI-BIRD: Today, you see gridlock in a lot of major cities, around the world. In Asia and Europe, traffic is moving at about five to 10 miles an hour, and people are stressed out.
ZIYA TONG: But what if you could redesign a car in a way that could do away with all that stress and gridlock? Auto engineers have come up with an idea, embodied in this, a revolutionary new vehicle, called the EN-V.
When I typically picture a car, I think of, like, four wheels and a steering wheel, but what I'm looking at right now looks like it's more out of a videogame.
CHRIS BORRONI-BIRD: That's right. These vehicles are not cars in the traditional sense of the word.
ZIYA TONG: First of all, to get in you pop the hood.
You won't need to gas up ever again, because these high-tech vehicles are electric powered and can be charged in an ordinary outlet—no tailpipe and no toxic fumes.
They're powered by two motors, one in each wheel. Top speed? About 25 miles per hour. They weigh less than 1,000 pounds, a quarter of your average car. And when it comes to maneuverability, these tiny two-seaters can turn on a dime.
But there's one feature that makes these vehicles truly unique.
So right now, you're just in auto-drive mode, is that right?
ZIYA TONG: With the help of G.P.S., wireless and sensing technology, The EN-V can be driven hands-free, along a pre-programmed route. The idea is, you just get in, tell the car where you want to go, and it will take you there.
They can even drive on their own, no human required.
That is incredible. That looks like a ghost car, though, in the way it's driving itself, right? It's actually a bit spooky.
Spooky or not it can also do this.
. stop by itself, when something is in its path.
CHRIS BORRONI-BIRD: These vehicles know each other's location and direction of movement and speed of movement.
ZIYA TONG: That's because sensors, equipped with vision and ultrasonic technology, give them the ability to sense objects around them. And a wireless network enables them to "talk" with one another, just like computers communicate through the Internet. But instead of sending emails, they share their position and velocity.
So right now, because this vehicle talked to the other vehicle, the other EN-V, it saw us coming and it stopped?
ZIYA TONG: That's great. So this would prevent accidents?
PRI: This would prevent accidents.
ZIYA TONG: And, in theory, if cars never hit each other, they don't need to be designed like cars.
DANIEL DARANCOU (General Motors) : You eliminate the airbags. You eliminate a huge plate of metal between you and the road. We do have seatbelts in there for that inadvertent bump, or, let's say, you fall asleep, so you don't fall out of the seat.
ZIYA TONG: For its debut, three design teams from around the world were invited to create their vision of the car of the future.
DANIEL DARANCOU: The vehicle that was designed in Europe—you know they have all the runways in Milano and Paris—that vehicle is called the Fashionista. It has a very expensive aura to it.
ZIYA TONG: The blue bubble I rode in was designed in Australia. It's called Cute and Friendly.
And the black one that looks a bit like Darth Vader was designed in California.
DANIEL DARANCOU: That one we call the Techno-Geek.
ZIYA TONG: Not only can Fashionista, Cute and Friendly and Techno-Geek drive themselves they can also pick you up.
CHRIS BORRONI-BIRD: The car of the future, like EN-V, you call the vehicle, and it will come to you. I just press this button and it will come and pick me up.
Because walking to a car is so 20th-century.
ZIYA TONG: This is so much cooler than valet I love it.
Chris hopes these cars will dominate cities of the future and make gridlock a thing of the past.
CHRIS BORRONI-BIRD: What I would like to see, by the year 2030, is that people would still have that freedom of movement that an automobile gives them today, but these vehicles would be communicating with each other and sensing each other, and traffic would flow a lot more smoothly, and people would be able to relax in the vehicle. But what really gets me excited is the fact that this vehicle could really provide accessibility to people who currently don't have accessibility to an automobile. I'm thinking of people who are old, people who are very young and people who are disabled.
ZIYA TONG: When will the EN-Vs be road-worthy? It's hard to say. There are many technical hurdles still to overcome. In fact this poor little EN-V ran out of steam right in the middle of our drive.
And cars like this aren't equipped to drive on the highway alongside unpredictable humans.
To be safe, the EN-Vs will need roadways of their own, where cars, not people, are in control.
Until then, cars like these will remain the stuff of automakers' dreams and designers' fantasies.
Weren't we all supposed to have jetpacks by now?
They're not that easy to make.
But some brave souls kept at it.
And now there are some jetpacks out there that really fly!
NEIL DEGRASSE TYSON: Dreams about the future are always filled with gadgets.
Already, we've got plenty—smart phones, computers, tablets—and, at the rate we're going, we're sure to get more. But all these wonders of technology rely on a tricky commodity: electricity.
And the truth is, the system that powers all this stuff is on its last legs.
ROBOT VOICE: Recharge battery.
NEIL DEGRASSE TYSON: Recently, I met up with some people who are racing to re-invent the electrical lifeblood of our technological age, so that our visions for the future won't be left in the dark.
I'm about to get a bird's-eye view, of the most interconnected machine on Earth: made up of more than 5,000 power plants, 200,000 miles of transmission lines, delivering electricity to millions of American homes, a 20th century marvel of engineering: our electric grid.
So, I'm looking at the network of transmission lines. They just go far and wide.
ERIC LIGHTNER (United States Department of Energy) : Yes, they do. The electrical grid is basically an interstate for electricity, and it goes all over the whole country.
NEIL DEGRASSE TYSON: The grid got its start during the Depression, when the federal government brought electricity to the heartland. But this century-old marvel of engineering is ill-equipped to handle the demands of an energy -hungry society.
Not only is it dirty, about half of our electricity comes from coal-burning power plants that emit greenhouse gases. More than half of our energy is lost in the way we produce, transmit and use it.
According to Eric Lightner, director of the Federal Smart Grid Task Force, the best way to make our grid more efficient and tackle climate change is with a smart grid.
Smart grid? That means right now it's a dumb grid?
ERIC LIGHTNER: Well, it's not as smart as it could be. Let's just say that.
NEIL DEGRASSE TYSON: An underachieving grid.
ERIC LIGHTNER: Yeah. There you go: an underachieving grid.
NEIL DEGRASSE TYSON: There's no better place to see how the grid works and why it needs some smarts, than here. Think air traffic control, but instead of coordinating 747s, these dispatchers monitor the flow of a dynamic and dangerous force that travels close to the speed of light.
Electricity starts its journey to us from huge power plants, like this, where, first, coal is burned to heat water.
The water turns to steam, which spins a turbine that turns a generator that forces tiny particles called electrons through a wire. That's electricity.
No matter how you generate that flow of electrons, the amount has to be just right. That's because too few electrons can cause a blackout, and too many can fry your electronics.
ERIC LIGHTNER: As demand increases or decreases, a power plant has to either go up or down to meet that demand.
NEIL DEGRASSE TYSON: And you're monitoring this in real time?
ERIC LIGHTNER: In real time. It's a very delicate balancing act.
NEIL DEGRASSE TYSON: These dispatchers are desperately trying to maintain that delicate balance.
GRID OPERATOR ONE: Something just happened.
NEIL DEGRASSE TYSON: For instance, in this drill, a generator has suddenly gone offline.
GRID OPERATOR TWO: We just lost a large unit in the west.
NEIL DEGRASSE TYSON: These grid operators have only a few minutes to solve the problem, and they're forced to do it the old fashioned way, by getting on the phone with power plants in search of more electrons. If they can't find them, they turn to power plants like this one.
It's called a "peaker" plant, because it's only used during power peaks, about a hundred hours a year. The rest of the time plants like this are sitting around on standby, a wasteful and expensive way to produce energy. In fact, about 25 percent of the cost of producing electricity is spent keeping these plants on hold.
But dispatchers don't have much of a choice.
GRID OPERATOR Frequency's back to normal.
NEIL DEGRASSE TYSON: And here's where a smart grid could make a real difference, starting with those old-fashioned power lines.
At the Electric Power Research Institute they're working on giving them some smarts.
ANDREW PHILLIPS (Electric Power Research Institute) : We're going to install sensor 460 on the closest line.
NEIL DEGRASSE TYSON: This little sensor may not look high-tech but it has the ability to analyze the condition of a power line.
RESEARCHER (Electric Power Research Institute) : Going hot on four.
NEIL DEGRASSE TYSON: For instance, when too many electrons flow through a power line, it gets so hot it starts to sag. Not only that.
ANDREW PHILLIPS: When a line sags it gets closer to the ground, and, therefore, it gets closer to trees. And the electricity going down the line will now go down the tree.
NEIL DEGRASSE TYSON: The result? A blackout, like the one in 2003 that shut down power to millions of people, in eight states and parts of Canada.
VIJAY VAITHEESWARAN ( The Economist ) : What caused the blackout in 2003? You can put it simply and say there were some mischievous trees that decided to knock down some power lines, and at some level that's true. But the deeper reason is that the grid operators at the utilities didn't have the technical capacity to tell them what was happening on their own power lines.
NEIL DEGRASSE TYSON: Smart sensors like this, can analyze the condition of a power line and send that information wirelessly to grid operators, before the lights go out.
But to make our grid truly efficient, it must undergo an even larger transformation.
VIJAY VAITHEESWARAN: Imagine if the Internet were to merge somehow with the dumb electricity grid we have. That's the kind of embedded intelligence a smart grid should have.
NEIL DEGRASSE TYSON: Intelligence that starts at the power plant and travels all the way to your home. Here's how the grid of the future will work. Your electric company is going to swap your old meter with a smart meter, equipped with wireless communication. All your appliances will be also be smart, they'll be able to communicate with your meter, which in turn will be in constant contact with the grid. This two-way communication between your electric company and your home will enable the grid to actually ask you for help, when it's running low on electrons.
Let's say you're running your clothes dryer and your meter gets a signal that the grid needs power. It can turn down the heat, freeing up some electrons for use elsewhere.
ERIC LIGHTNER: All that happens is your dryer will turn off the heat for 30 seconds the drum will continue to spin. You will never even know that that event took place.
NEIL DEGRASSE TYSON: The same thing will happen with your air conditioner, dishwasher, even your water heater. And when millions of homes, with tens of millions of smart appliances do the same, dispatchers will have a whole new way to prevent blackouts and get more mileage out of the electricity we generate.
There's no doubt that transforming the most interconnected machine on Earth into one of the smartest is a colossal task, but if we want to tackle global climate change and keep the lights on for generations to come, it's a challenge we'll have to face.
VIJAY VAITHEESWARAN: Some people think that because the smart grid is such a huge project it can't get done, but let's remember, energy is the biggest industry on Earth, by far. And we can't live without it.
La Rete Intelligente (The Smart Grid)
The earliest and largest example of a smart grid is in Italy
Where 85% of homes have smart meters,
the highest percentage in the world.
The system can remotely turn power on and off,
and detect service outages.
It is truly the Next Thing Big.
NEIL DEGRASSE TYSON: Pretty much every plant and animal alive today is the result of eons of natural cross-breeding.
We are, of course, the products of our parents and grandparents and all our ancestors.
This orange takes it a step further. It's the result of farmers intentionally cross-breeding different types of oranges to get bigger, juicier, tastier fruit. What they're doing is manipulating genes, D.N.A., the instructions for all living things.
But what if you could go even further and actually write genetic code from scratch? In this episode's profile, we meet one scientist who's trying to do just that: custom design totally new forms of life that, one day, might save the world.
Jay Keasling was raised to work the earth, but instead, this tough Nebraska farm boy might just save the world. And before you think talk like that's just a bunch of manure, well, Jay can tell you all about manure.
JAY KEASLING: We had 200 pigs, and with 200 pigs, there's a lot of manure. And this was really hard work, scooping pig manure.
MAX KEASLING (Jay Keasling's Father) : It was no fun at all. Nobody enjoyed it.
JAY KEASLING: And that was probably the worst job. I like to say I spent the first 18 years of my life with the smell of pig manure on my hands.
NEIL DEGRASSE TYSON: Today, Jay's got plants, not pigs, and the manure isn't on his hands so much as it's on his mind. Jay Keasling is a pioneer in the field of synthetic biology, who's doing amazing things with the waste from bacteria.
He's doing it here, at the Bay Area's Joint BioEnergy Institute, or as everyone around here calls it, "j-bay," though they swear there's no pun intended.
BLAKE SIMMONS (Joint BioEnergy Institute) : You could say the acronym a lot of different ways, but we happen to call it j-bay.
NEIL DEGRASSE TYSON: Hmmm. No matter what you think about the nickname, JBEI starts with Jay. Jay is the hard working C.E.O. who pays attention to every detail, from lab work.
JAY KEASLING: What's going on right now?
NEIL DEGRASSE TYSON: . to the method for hanging wall posters.
JAY KEASLING: What you should do is make sure they have two clips and two wires for each poster.
And who says I don't micro-manage?
NEIL DEGRASSE TYSON: Actually, Jay is a microbe manager. His first major victory was engineering e coli—a bacterium found in everyone's gut—to produce a drug that will help to cure malaria. Malaria kills nearly a million people each year, or, a child in Africa every 45 seconds. It's a terrible drain on a nation's productivity. And it can be cured by a drug called artemisinin, which comes from a plant that can be difficult to grow, so it can be very expensive to produce.
JAY KEASLING: And the price was too high for people to afford.
NEIL DEGRASSE TYSON: Jay saw the perfect opportunity: to engineer bacteria to squirt out artemisinin.
JAY KEASLING: I view microbes as little chemical factories. We're doing the same thing inside the cell, it's just billions of times smaller.
NEIL DEGRASSE TYSON: And here's how Jay and his team set out to build a microbial factory for the anti-malarial drug: they wrote new genetic code then machines assembled it from the four basic chemical ingredients of D.N.A. they took those synthesized genes and mixed them with genes from yeast and other bacteria, to re-engineer the insides of e coli. And it worked. With custom-made microbes, the life-saving anti-malarial drug can be produced so efficiently, a dose will cost pennies instead of dollars.
JAY KEASLING: We could save on the order of 500,000 lives a year.
BLAKE SIMMONS: It really set Jay apart from the rest of the field, in using synthetic biology as a way to tackle some of the biggest problems that are out there.
NEIL DEGRASSE TYSON: Jay got a $43 million grant from the Gates Foundation, and started a company to find ways to take his innovations from the microbe to the market.
JAY KEASLING: It was clearly one of the most exciting periods of my life.
NEIL DEGRASSE TYSON: Jay had matched his renowned imagination with his prodigious work ethic. Even late at night, he problem-solves during his workout.
And with two young sons, Jay is determined to take on other challenges facing our planet.
For his next mission, he's reaching back to the roots of his ambition and optimism, back where it all started: on the farm.
JAY KEASLING: My work now relates much more to the farm than it ever has.
NEIL DEGRASSE TYSON: Life in Harvard, Nebraska, as in many small farm towns today, is challenging. Jay remembers his childhood fondly, though it was challenging, too.
JAY KEASLING: It was actually a great place to grow up. My father was very quiet, extremely hard working.
From my mother, I think I got a lot of determination, strong will, focus. I think that's been really important for me.
NEIL DEGRASSE TYSON: Jay's mother died when he was only 11 years old.
JAY KEASLING: I remember it clearly. She had had cancer, breast cancer, was cured of it, or it was in remission, at least, coming home from her last doctor's appointment. Corn was very tall, so it's hard to see cars coming. She crossed from stopping at a stop sign, was hit by another car, and that car was driven by her first cousin. Both of them died, so. pretty tragic for our family.
MAX KEASLING: It was a tough time of our life. It really was. We just survived and got along. You know, you adjust, and do what you have to do.
Jay was old enough that he really knew, you know? He was 11 years old. Him and his mother were really close, and. as we all were. But it was tough on Jay.
JAY KEASLING: I had to work even harder. There was very little time for fun and games. And that's actually okay that's served me pretty well, I think, because right now, there's pretty much no amount of work that seems insurmountable for me.
NEIL DEGRASSE TYSON: And work hard, he did. Jay became class valedictorian. The small town couldn't hold his ambition, but he was driven to leave by another reason, one that he kept secret.
JAY KEASLING: Being gay in small-town Nebraska is difficult. People who were, if there were any, were certainly not out, and so you had no examples at all.
NEIL DEGRASSE TYSON: Throughout college, in Lincoln, while getting his Ph.D. at Michigan, Jay never told his family he was gay. He didn't come out until he arrived at Berkeley.
JAY KEASLING: My father was fine with it.
MAX KEASLING: I just accepted it. He's my son, you know?
JAY KEASLING: It shouldn't matter what ethnicity, what sexual preference you are, anything. It's all about the work.
NEIL DEGRASSE TYSON: Now, the mixture of Jay's famous drive and tolerance has led him to design a highly unusual team, reflecting those qualities. There, working side by side, are engineers, biologists, chemists, all working around the clock, under the same roof.
AINDRILA MUKHOPADHYAY (Joint BioEnergy Institute) : My background is chemistry.
ERIC STEEN (Joint BioEnergy Institute) : I'm actually a graduate student in the department of bioengineering.
PAMELA PERALTA-YAHYA (Joint BioEnergy Institute) : He hires people that are strong in their field and expects them to take ownership of the project and get it done.
NEIL DEGRASSE TYSON: Jay has assembled a multidisciplinary team, every bit as driven as he is, to work on his next big vision. Their mission: solving the world's energy crisis by manipulating bacteria to produce biofuels that will replace oil.
JAY KEASLING: Petroleum's running out. And it's going to run out even faster, the more the population starts to drive and more economies grow.
This is bio-diesel that's being secreted by e coli.
NEIL DEGRASSE TYSON: Jay and his team have already engineered the D.N.A. of e coli to produce bio-diesel from switchgrass. See those little bubbles right there? That's actually fuel, straight from bacteria, ready for a car.
JAY KEASLING: And that could just be siphoned off and put into a tank.
NEIL DEGRASSE TYSON: They've demonstrated the concept of turning sugar from switchgrass into biofuel, and the next step is figuring out how to make the process practical on an enormous scale, one big enough to save the world. And by planting all the switchgrass to make this new biofuel, it might just save places like Harvard, Nebraska, and the farm that's been in Jay's family for five generations.
JAY KEASLING: Someday, these fields will be planted in switchgrass. And these bales will be the cellulose that goes into the fermentation facility that produces our advanced biofuels.
NEIL DEGRASSE TYSON: Biofuels that will go into our cars, our planes, our factories.
JAY KEASLING: This is the future of energy for the U.S.
MAX KEASLING: What Jay's doing now could help us a great deal in the future. We could raise lots of acres of switchgrass. And he seems to be pretty positive about that.
JAY KEASLING: We're trying to make the Midwest into the new Mid-east.
NEIL DEGRASSE TYSON: And from around these parts, that would definitely be the next big thing.
And now for some final thoughts on The Next Big Thing.
For most of human civilization, the pace of innovation has been so slow
that a generation might pass before a discovery would influence your life, culture or the conduct of nations.
Today, and for a while now, we've come to expect major changes, several times within a decade, especially among the developed countries. Some are big and obvious: the invention of the telephone, the car, the airplane, the computer. Some are big, but unfold slowly: electrified cities and countrysides, access to abundant supplies of food, or the countless ways we can now communicate with one another.
Some of my favorite big things are the accumulations of little things, like the unending role of composite materials in our lives, or the steady growth and power of the Internet.
More often than not, the next big thing takes you by surprise. You don't see it coming. You don't know or believe you need it. Then the inevitable happens: you can't live without it.
A last category of "big thing" comes from the discovery of ideas or perspectives. In 1968, Apollo 8 was the first spacecraft ever to leave Earth for another destination: the Moon. Astronauts on board didn't land, but looped around the back side and snapped a photo of Earthrise over the barren lunar land surface. It took a voyage to the Moon to see Earth for the first time.
Enlightened and empowered by that single image, we transformed the way we care for our planet, which may just be the biggest thing of them all.
And that is the Cosmic Perspective.
. and now weɽ like to hear your perspective on this episode of NOVA scienceNOW.
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NOVA scienceNOW: What's the Next Big Thing?
This material is based upon work supported by the National Science Foundation under Grant No. 0917517. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.
Materials Used for the Construction of Roads: Methods, Process, Layers and Road Pavement
A wide variety of materials are used in the construction of roads these are soils (naturally occurring or processed), aggregates (fine aggregates or coarse aggregates obtained from rocks), binders like lime, bituminous materials, and cement, and miscellaneous materials used as admixtures for improved performance of roads under heavy loads and traffic.
Soil constitutes the primary material for the foundation, subgrade, or even the pavement (for low-cost roads with low traffic in rural areas). When the highway is constructed on an embankment at the desired level, soil constitutes the primary embankment material further, since all structures have to ultimately rest on and transmit loads to ‘mother earth’, soil and rock also serve as foundation materials.
Soil is invariably used after some process of stabilisation such as compaction and strengthening by adding suitable admixtures for improving the performance of the road. Mineral aggregates obtained from rocks form the major component of the sub-bases and bases of highway pavements of almost all types.
A detailed study of their properties is therefore essential. Binder materials such as bitumen and cement mixed with appropriate types and proportions of aggregates are used for the construction of superior types of roads that are characterised by their durability and load-carrying capacity. Thus, base courses, sub-base courses and even the surface or wearing courses require the use of these materials.
Soils can be studied effectively if they are classified according to certain principles into a definite system. A system is an ordered grouping of certain elements in a discipline according to pre-defined principles. Just as classification or grouping is practised in scientific disciplines such as chemistry, zoology and botany, it is used in Geotechnical Engineering as well.
A soil classification system may be defined as a fundamental division of the various types of soil into groups according to certain parameters such as its physical properties, constituents or texture, field performance under load, presence of water and so on. There are a few field identification tests have been developed for preliminary identification in the field.
Need for Soil Classification:
Soil deposits in nature are never homogenous in character wide variations are observed in their properties and behaviour. Soils that exhibit similar average properties may be grouped as a class. Classification of soil is necessary to obtain an appropriate and fairly accurate idea of the properties and behaviour of a soil type.
A classification system is usually evolved with a view to assessing the suitability of a soil for specific use as a construction material or as a foundation material. In view of the wide variations in engineering properties of several soils, it is inevitable that in any system of classification, there will be borderline cases which may fall into groups that appear to be radically different under different systems of classification.
Hence, classification is taken only as a preliminary requirement to study the engineering behaviour of a soil special tests may become necessary in any project of importance.
Requirements of a Soil Classification System:
The general requirements of an ideal soil classification system are:
(i) It should have a scientific basis.
(ii) It should be relatively simple and objective in approach.
(iii) The number of groupings and properties used as the criteria should be limited.
(iv) The properties considered should be relevant to the purpose of classification.
(v) A generally accepted uniform soil terminology should be used.
(vi) It should indicate the probable performance of the soil to a satisfactory degree of accuracy.
(vii) Group boundaries should be drawn as closely as possible where significant changes in soil properties occur.
(viii) It should be acceptable to all engineers.
These are rather ambitious requirements and cannot be expected to be met by any system, primarily because of the complex nature of soil, which does not lend itself to a simple classification. Therefore, a soil classification system is probably satisfactory only for the specific engineering application for which it was developed.
Although several classification systems have been developed, some being relatively more elaborate and exhaustive than others, the following systems only will be considered:
(a) Textural classification
(b) PRA system of classification (Group index method)
(c) Unified soil classification System
(d) Indian Standard Soil classification system
(a) Textural Classification:
Textural or grain size classification of soil is based on the particle size of the soil. Terms such as gravel, sand, silt and clay are used to indicate the ranges of grain size. Natural soil is invariably a mixture of particles of various sizes.
Although several textural classifications have been proposed, including the PRA system, the MIT classification and the IS textural classification are considered here in view of their wider acceptance.
MIT Textural Classification:
This was developed by the Massachusetts Institute of Technology, USA. The ranges of grain sizes in this scale, along with the soil designations, are given below (Fig. 6.7).
IS Textural Classification:
The ranges of sizes in the IS textural classification scale, along with the soil designations, are given below (Fig. 6.8).
This forms part of the Indian Standard Soil Classification System. In general, textural classifications are inadequate primarily because plasticity characteristics do not find any place in them.
(b) PRA System of Classification (Group Index Method):
The US Bureau of Public Roads developed a classification system, called the Public Roads Administration (PRA) classification system in 1931, specifically meant for use in road construction. This was revised several times, and the one given here is that revised in 1945 by the American Association of State Highway and Transport Officials (AASHTO). This system is based on both particle size and plasticity characteristics.
According to this system, soils are classified into eight groups—A-1 to A-8, the last one being Peat. Some groups contain a few subgroups. Soils within each group are evaluated according to the group index (GI), calculated from the following empirical formula –
GI = 0.2 a + 0.005 ac + 0.01 bd … (6.55)
a = that part of the percent passing US Sieve No.200 (IS-75 μm) greater than 35, and not exceeding 75, expressed as a positive whole number (1 to 40)
b = that part of the percent passing US Sieve No.200 (IS-75 μm) greater than 15, and not exceeding 55, expressed as a positive whole number (1 to 40)
c = that part of the liquid limit greater than 40, and not greater than 60, expressed as a positive whole number (1 to 20) and,
d = that part of the plasticity index greater than 10, and not exceeding 30, expressed as a positive whole number (1 to 25).
The group index value should be rounded off to the nearest integer in case any of the above values is less than the minimum limit, it should be taken as zero.
In general, the greater the group index value, the less desirable the soil is for highway construction within that subgroup.
The details of the groups and subgroups are set out in Table 6.1.
This system was originally developed by Arthur Casagrande and adopted by the US Corps of Engineers in 1942 as ‘Airfield Classification’. It was later revised for universal use and re-designated as the Unified Soil Classification in 1953.
In this system, soils are classified into three broad categories:
(i) Coarse-grained soils with up to 50% passing No.200 American Standard Testing Service (ASTM) Sieve (75 μm-IS sieve).
(ii) Fine-grained soils with more than 50% passing No.200 ASTM Sieve (75 μm-IS sieve).
The first two categories can be distinguished by their plasticity characteristics. The third can be easily identified by its colour, odour and fibrous nature.
Each soil component is assigned a symbol as follows:
Silt: M (from the Swedish word, ‘mo’ for silt)
Coarse-grained soils are further sub-divided into well-graded (W), and poorly-graded (P) varieties, depending upon the uniformity coefficient (U) and the coefficient of curvature (Cc) –
Well-graded soil, Cc = 1 to 3.
Fine-grained soils are subdivided into those with low plasticity (L), with ωL < 50%, and those with high plasticity (H), with ω L > 50%. The plasticity chart devised by Casagrande is used for the identification of fine-grained soils (Fig 6.9) –
The relevant Indian Standard is “IS: 1498-1970, classification and identification of soils for engineering purposes (First Revision.)”.
The significant provisions of this system are given below:
(1) Coarse-grained soil – More than 50% of the total material by weight is larger than 75 μm IS sieve size.
(2) Fine-grained soil: More than 50% of the total material by weight is smaller than 75 μm IS sieve size.
(3) Highly Organic Soil and Other Miscellaneous Soil Materials:
These soils contain large percentages of fibrous organic matter such as peat and particles of decomposed vegetation.
In addition, certain soils containing shells, cinders and other non-soil materials in sufficient quantities are also grouped in this division.
Coarse-grained soils shall be divided into (a) gravels and (b) sands.
(a) Gravels – More than 50% of coarse fraction (+75 μm) is larger than 4.75 mm IS sieve size.
(b) Sands – More than 50% of coarse fraction (+75 μm) is smaller than 4.75 mm IS sieve size. Fine-grained soils can be subdivided into
(ii) Silts and clays of medium compressibility – Liquid limit greater than 35% and less than 50% (I).
Coarse-grained soils shall be further subdivided into eight basic soil groups, and the fine­grained soils into nine basic soil groups highly organic soils and other miscellaneous soil materials shall be placed in one group.
The Plasticity Chart used in IS system of soil classification is shown in Fig. 6.10.
Based on laboratory tests and the results in the form of consistency limits, the plasticity chart forms the basis for the classification of fine-grained soils.
Organic silts and clays are distinguished from inorganic soils which have the same position on the plasticity chart, by odour and colour. In case of doubt, the material may be oven-dried, remixed with water, and retested for liquid limit. The plasticity of fine-grained organic soils is considerably reduced on oven-drying.
Oven-drying affects the liquid limit of inorganic soils also, but only to a small extent. A decrease in liquid limit on oven-drying to a value-less than three-fourths of that before oven-drying is a positive identification of organic soils.
These are inorganic clays of medium to high compressibility. They are characterised by high shrinkage and swelling characteristics. When plotted on the plasticity chart, they lie mostly along a band above the A-line. For some, the band may lie below the A-lie also.
Kaolin behaves like inorganic silt and usually lies below the A-line this shall be classified as such (ML, MI and MH), although it is clay from mineralogical stand point. The classification criteria for coarse-grained soils are given in Table 6.4.
Coarse-grained soils with 5% to 12% fines are considered border-line cases between clean and dirty gravels or sands-for example, GW-GC, or SP-SM. Similarly, border-line cases might occur in dirty gravels and dirty sands, where Ip is between 4 and 7- for example, GM-GC, or SM-SC. It is, therefore, possible to have a border-line case of a border-line case. The rule for correct classification in such cases is to favour the non-plastic classification.
For example, gravel with 10% fines, a U-value of 20, a Cc -value of 2.0, and IP of 6 would be classified GW-GM, rather than GW-GC.
Note – Even separate flow-charts may be shown for coarse-grained and fine-grained soils.
Relatively Suitability for General Engineering Purposes:
The characteristics of the various soil groups pertinent to roads and airfields-value as subgrade, sub-base and base material, compressibility, drainage characteristics, compaction characteristics, dry unit weight, CBR-value, and subgrade modulus are all tabulated in “IS: 1498-1970 – classification and identification of soils for general engineering purposes”.
It also includes characteristics pertinent to embankments and foundations-values as embankment material, compaction characteristics, value as foundations material, requirements for seepage control, ranges of permeability and dry unit weight. Characteristics pertinent to suitability for canal sections compressibility, workability as a construction material and shearing strength when compacted and saturated are also given in relative terms or qualitative terms.
The information provided in IS: 1498-1970 serves the purpose of a guideline or an indication of the suitability of a soil based on the IS classification system. However, important and large projects need detailed investigation of the soil properties and engineering behaviour for good design.
2. Stone Aggregates :
Stone aggregate, or mineral aggregate, as it is called, is the most important component of the materials used in the construction of roads. These aggregates are derived from rocks, which are formed by the cementation of minerals by the forces of nature.
Stone aggregates are invariably derived by breaking the naturally occurring rocks to the required sizes. They are used for granular bases, sub-bases, as part of bituminous mixes and cement concrete they are also the primary component of a relatively cheaper road, called water-bound macadam.
A study of the types of aggregates, their properties, and the tests to determine their suitability for a specific purpose is of utmost importance to a highway engineer. Properties such as strength and durability of aggregates are generally influenced by their origin of occurrence, mineral constituents and the nature of the bond between the constituents.
Geologically speaking, rocks are classified into the following categories:
These are formed by the cooling, solidification and crystallisation of molten rock on the earth’s crust at different depths. The minerals, their proportions and the rate of cooling of the magma have a bearing on the strength characteristics of the rock.
Igneous rocks are, in general, stronger than the other two types. Granite, diorite and gabbro are intrusive rocks which form at deep layers in the earth’s crust. Basalt (or trap), andesite, rhyolite and dolerite are extrusive rocks which from at the top layers of the earth’s crust.
Fine material or rock fragments and particles transported by water or wind and deposited in layers, get hardened in course of time to form sedimentary rocks (the time required is on geologic scale). They consist of a layered structure the rock beds are stratified, they may be porous, and have relatively low strength.
Examples of siliceous variety are sandstone and argellite those of calcareous variety are limestone and dolomite.
These are formed by the modification and re-crystallisation of igneous rocks and sedimentary rocks by geological and natural agents such as temperature, pressure, moisture, humidity, and movement of rock beds.
Major changes occur in geologic time and form foliations. This kind of foliated structure makes these rocks comparably weaker than igneous rocks. Popular examples of metamorphic rocks are gneiss (from granite), slate (from shale) and schist.
Examples of un-foliated types are marble (from limestone) and quartzite (from sandstone). (Marble and gneiss are used for flooring and face work in buildings.)
Desirable Properties of Sand Aggregates:
The following properties are desirable in soil aggregates used the construction of roads:
It is the resistance to crushing which the aggregates used in road construction, especially in the top layers and wearing course, have to withstand the stresses due to wheel loads of the traffic in addition to wear and tear.
It is the resistance to abrasion of the aggregate at the surface. The constant rubbing or abrading action between the tyres of moving vehicles and the exposed aggregate at the road surface should be resisted adequately.
This is the resistance to impact due to moving traffic. Heavily loaded trucks and other vehicles cause heavy impact loads on the road surface while moving at high speeds, and while accelerating and decelerating. Even steel-typed vehicles, though moving slow, cause heavy impact on the aggregates exposed at the surface. Hence, resistance to such impact forces is a desirable quality.
It is the resistance to the process of disintegration due to the weathering action of the forces of nature. The property by virtue of which the aggregate withstands weathering is called soundness. This is also a desirable property.
It is the ability of the aggregate to form its own binding material under traffic, providing resistance to lateral displacement. Limestone and laterite are examples of stones with good cementing quality. This becomes important in the case of water-bound macadam roads.
Aggregates maybe either rounded, cubical, angular, flaky, or elongated. Each shape is appropriate for a certain use. Too flaky and too elongated aggregates have less strength and durability so they are not preferred in road construction.
Rounded aggregates are good for cement concrete because of the workability such aggregates provide. Cubical or angular aggregates have good interlocking properties since flexible pavements derive their stability due to interlocking, such aggregates are the preferred type for construction. Thus, the appropriate shape for a particular use is also a desirable property.
(vii) Adhesion with Bitumen:
The aggregates used in bituminous pavements should have less affinity to water than to bitumen otherwise, the bituminous coating on the surface of the aggregate will get stripped off in the presence of water. So, hydrophobic characteristic is a desirable property for aggregates to be used in the construction of bituminous roads.
This is mutual rubbing of aggregates under traffic adequate resistance to attrition is a desirable property.
This is a measure of the degree of fineness or smoothness of the surface of the aggregate.
Gravels from river beds are fairly smooth as a rule, fine grained rock is highly resistant to wear and is preferred for surface courses.
3. Bituminous Materials :
Bitumen was used as a bonding and water-proofing agent thousands of years ago. However, the use of bitumen for road-making picked up only in the nineteenth century. As the quest for fuels like petroleum to run automobiles grew and the distillation of crude oil emerged as a major refining industry, the residues known as bitumen and tar found increasing use in constructing bituminous surfaces, which provided superior riding surface.
The definition for the term, bitumen, given by the American Society for Testing Materials (ASTM) runs thus:
“Bitumen is a hydrocarbon material of natural or pyrogenous origin, which is in a gaseous, liquid, semi-solid, or solid state, and which is completely soluble in carbon disulphide (CS2).”
Of course, bitumen is found to be soluble to a large extent in carbon tetrachloride (CCl4) also. Bitumen is a complex organic compound and occurs either as such in nature or can be obtained during the distillation of petroleum it is generally non-volatile and resistant to most acids, alkalis and salts.
Bitumen occurring in nature as rock intrusions invariably contains inert inorganic materials or minerals in such a case it is called asphalt. It is also found in lakes (as in Trinidad), in which case it is called lake asphalt. However, in American terminology, bitumen itself is termed asphalt, irrespective of whether it contains inorganic/mineral matter or not. In India, the British terminology is used for the terms bitumen and asphalt.
1. Predominantly hydrocarbons, with small quantities of sulphur, nitrogen and metals.
2. Mostly (up to 99.9%) soluble in carbon disulphide (CS2), and insoluble in water.
3. Softens on heating and gets hardened on cooling.
4. Highly impermeable to water.
5. Chemically inert and unaffected by most acids, alkalis and salts.
6. No specific boiling point, melting point or freezing point a form of ‘softening point’ is used in their characterisation.
7. Although generally hydrophobic (water repellent), they may be made hydrophilic (water liking) by the addition of a small quantity of surface-active agent.
8. Most bitumens are colloidal in nature.
1. Workability – Bitumen should be fluid enough at the time of mixing so that the aggregates are fully coated by the binder. Fluidity is achieved either by heating or by cutting back with a thin flux or by emulsifying the bitumen.
2. Durability – There should be little change in viscosity within the usual range of temperatures in the locality.
3. Volatile constituents in bitumen should not be lost excessively at higher temperatures to ensure durability.
4. It should have enough ductility to avoid brittleness and cracking.
5. Strength and adhesion – The bitumen should have good affinity to the aggregates and should not be stripped off in the continued presence of water.
A few more terms relating to bitumen/asphalt are:
Bitumen derived from the refining of petroleum for which the viscosity has not been adjusted by blending with flux oil or by softening with any cut-back oil or by any other treatment. It generally has high viscosity.
A binder consisting of bitumen, or a mixture of lake asphalt and bitumen or flux oils, specially prepared as per prescribed quality and consistency for direct use in paving, usually in the hot condition.
Oxidised or Blown Bitumen:
Bitumen obtained by further treatment of straight-run bitumen by running it, while hot, into a vertical column and blowing air through it. In this process, it attains a rubbery consistency with a higher softening point than before.
Asphalt/bitumen dissolved in naphtha or kerosene to lower the viscosity and increase the workability.
A mixture in which asphalt cement, in a finely dispersed state, is suspended in chemically treated water.
Include cut-backs in naphtha and kerosene, as also emulsified asphalts.
A bituminous material, generally liquid, used for softening other bituminous materials.
The main source of bitumen is petroleum crude. Refining of petroleum crude involves fractional distillation. The crude oil is heated in a tube-still to about 200°C to 400°C and injected into a fractionating column. As the pressure is suddenly reduced, the volatile fractions with low boiling points get vaporised and go up the column, from where they are carried through condensers.
Gasoline, kerosene, diesel oil, and lubricating oils, constituting the light, medium and heavy distillates with gradually increasing boiling points, thus get collected. The heavy residue left at the bottom is collected as bitumen. Steam is injected into the fractionating column to help in the separation process of the fractions. The steam and vacuum distillation process is only a physical process and does not involve any chemical changes.
In modern refining processes, the distillation is carried out in stages. In the first stage, the temperature in the tube-still is kept relatively low (say 300°C to 350°C) and the light and medium fractions are separated in the fractionating column operating at atmospheric pressure.
The crude left is then passed through another still for subsequent transfer to another column operating under vacuum and injected with steam. The latest process dispenses with steam and relies on dry vacuum only, thus enabling a wide range of bitumen to be produced.
Paraffinic crudes yield, on distillation, an undesirable wax-like residue. Naphthenic crudes yield practically wax-free bitumen crude from middle-east yields good bitumen. The heavy residue may be blown with air at high temperature in a converter to produce air-blown or oxidised bitumen.
They are stiff even at high atmospheric temperatures. Such bitumen are not used for pavements, but are good as roofing materials and water-proof paints. It is also used as filler material for cracks and joints in concrete pavements.
A schematic flow-chart for petroleum refining is shown in Fig. 6.65.
Cut-back bitumen is one, the viscosity of which is reduced by adding a volatile diluent. Penetration grade bitumens require to be heated to a specified temperature to lower its viscosity before it is applied on a road to facilitate coating the pre-heated aggregate. To obviate the need for heating the aggregate, cut-backs come in handy. Upon application, the volatiles slowly evaporate, and leave behind the original bituminous binder.
There are three types of cut-backs based on the diluent (dilutant or solvent) used:
1. Rapid-curing (RC) cutback – Bitumen blended with gasoline or naphtha, (highly volatile, low viscosity)
2. Medium-curing (MC) cutback – Bitumen blended with kerosene or coal tar creosote oil (medium viscosity)
3. Slow-curing (SC) cutback – Bitumen blended with gas oil (low viscosity, highly viscous)
Each of these has been categorized based on their initial kinematic viscosity values as follows:
1. RC 70, RC 250, RC 800, RC 3000
2. MC 30, MC 70, MC 250, MC 800, MC 3000
3. SC 70, SC 250, SC 800, SC 3000
Further details and specifications for these cutbacks are given in “IS: 217-1988: Specification for cutback bitumen, Bureau of Indian Standards, New Delhi, 1993”.
Since cutbacks contain volatile solvent, some of which may enter water bodies and air, they may cause environmental pollution. Also, since the solvent is inflammable, it may increase the possibility of fire hazard and cause concerns related to safety during handling and application. Therefore, cutbacks are being gradually replaced by emulsions.
A bitumen emulsion is obtained by blending bitumen with water and an additive called an emulsifier. The emulsified suspension contains dispersed minute particles of bitumen (that is, oil in water). In a bituminous emulsion, bitumen is the ‘dispersed’ phase (minutely subdivided particles), while water is the ‘continuous’ phase in which it is not soluble. The amount of bitumen to be mixed with water may range from 40 to 70% depending upon the intended use of the suspension.
Based on the type of emulsifier used, the bitumen particles can be negatively charged or positively charged. If they are negatively charged, ‘anionic bitumen emulsions’ are obtained, and if they are positively charged, ‘cationic emulsions’ are got.
Fatty acids derived from mineral, vegetable or wood sources saponified with sodium or potassium hydroxide are used as emulsifiers for producing anionic emulsion. For cationic emulsions, the emulsifiers are generally amine salts produced by the reaction of organic amine or diamine with acetic acid or hydrochloric acid.
The type of emulsion should be selected based on the mineral composition of the aggregate used for the bituminous mix. For example, for an aggregate rich in silica (SiO2) which has a strong electronegative charge on the surface, cationic emulsions are suitable with electropositive charge on the suspended bitumen particles. The mix then becomes electrostatically stable and produces a strong layer when compacted.
Bitumen emulsions, like cutback bitumens, are also classified into three types based on their setting times:
1. Rapid-setting emulsions (RS)
2. Medium-setting emulsions (MS)
3. Slow-setting emulsions (SS)
Setting, in this context, means separation of the emulsion. When the water in the emulsion evaporates, the minute bitumen particles in the emulsion coat the surface of the aggregates curing takes place, by which the compacted layer of the emulsion-aggregate mix hardens and attains strength. Therefore, rapid-setting emulsion sets and cures in a relatively quick manner.
“IS: 3117-2004: Anionic bitumen emulsions” covers anionic emulsions, while “IS: 8887- 2004: Cationic bitumen emulsions” covers cationic emulsions.
Setting and curing of emulsion mixes are affected by the following factors:
(i) Gradation, dust, dampness, water absorption and mineral composition and surface charge of/on the aggregates.
(iii) Meteorological conditions like climate, weather, temperature, humidity, wind velocity, etc.
(iv) Drainage conditions of the construction site.
Advantages of Emulsions:
1. Emulsions can be used under cold and damp weather conditions.
2. Strength properties of bitumen are preserved as they do not need hot mixing.
3. Better coating of aggregates due to low viscosity of the emulsion.
4. Ideal for patch repair work and sealing of cracks as no heating is required and better penetration into even minute cracks is possible.
5. Water-based nature of the emulsions makes them environment-friendly.
6. A lot of energy is conserved as there is no need for intensive heating (only warming is needed, if at all.)
Limitations of Emulsions:
1. The nature of the aggregate has to be verified before choosing an appropriate emulsion.
2. Setting time varies not only with the type of emulsion, but also with atmospheric conditions at the time of application.
3. Based on the particular need, care should be exercised in choosing the type of emulsion and the quantity needed for the desired grade of bituminous mix.
4. Storage time is relatively restricted.
5. Bitumen emulsions are more expensive than hot-mix bitumen.
6. In general, emulsion-based bituminous pavements using emulsions are not as good as hot- mix constructions for heavy traffic loads.
Specifications for paving bitumen are to be appropriately chosen based on the particular need and the Indian Standard specifications listed below:
IS: 1203, 1205, 1206 (Parts 2 & 3), 1208, 1209 and 1216 (1978, 2002) for tests.
IS: 73-2006 for paving bitumen.
IS: 217-1988, 1993 for cutback bitumen.
IS: 3117-2004 for anionic bitumen emulsions.
IS: 8887-2004 for cationic bitumen emulsions.
Specifications for paving grade bitumens (IS: 73-2006):
Tar is a black or brown to black, viscous, non-crystalline material having binding property. This is, therefore, the other category of bituminous materials.
Tar is obtained from the destructive distillation of organic materials such as coal, petroleum, oil, wood and peat, in the absence of air at about 1000°C. It is completely soluble in carbon tetrachloride (CCl4). It contains more volatile constituents than bitumen and is therefore more susceptible to change in temperature. Generally, tar is used for surface dressing on the wearing course since it has good adhesion in damp conditions.
Some more terms relating to tar are:
1. Coal tar – Tar produced by the destructive distillation of bituminous coal.
2. Coke-oven tar – A variety of coal tar obtained as a by-product from the destructive distillation of coal in the production of coke.
3. Oil-gas tar – A petroleum tar produced by cracking oils at high temperature in the production of oil-gas.
4. Water-gas tar – A petroleum tar produced by cracking oils at high temperature in the production of carburetted water-gas.
5. Refined tar – Produced from crude tar by distillation to remove water and to produce a residue of desired consistency.
6. Road tar – A tar refined in quality and consistency for use in paving of roads.
7. Pitch – Black or dark brown solid cementitious residue which gradually liquefies when heated and which is produced by distilling off the volatile constituents from tar.
Specifications for Road Tars:
Indian Standards classify road tars for paving purposes into five grades — RT1, RT2, RT3, RT4, and RT5, meant for specific purposes.
These are covered by “IS: 215-1995: Road tar: Specifications, Bureau of Indian Standards, New Delhi, 2000”.
The grades and specific uses are given below in Table 6.12:
Standard specification for road tars of the five standard grades based on the properties determined from tests on tar are given in the Table 6.13 [IS: 215-1995, 2000].
The coal-tar produced in the manufacture of coking coal requires carbonation at high temperatures above 1000°C. In view of the increasing demand for road tars in recent years, a new technology known as low temperature carbonisation has come into vogue.
In this, the carbonisation of coal is carried out in the temperature range of 600°-750°C in a smokeless fuel process. The crude tar thus produced is successfully used for making road tars these are known as low temperature tars.
A comparison of bitumen and tar is given below:
(i) Aggregates coated with tar exhibit lower stripping action than those coated with bitumen.
(ii) Tar is more susceptible to temperature than bitumen. It becomes liquid at relatively lower temperature.
(iii) Tar is not easily dissolved in petroleum solvents so it can be preferred for paving parking areas, where oils might drip from vehicles.
(iv) Since more setting time is required for tar, it may be processed at a mixing plant and carried to the construction site.
(v) In view of the higher free carbon content, tar is more brittle than bitumen.
(vi) As tars have more phenol content, they can get more easily oxidised than bitumen.
(vii) At higher temperatures, tar may be more easily affected than bitumen.
(viii) As more time is required for tar to set, tar-paved roads need to be closed to traffic for a longer time.
(ix) Both bitumen and tar appear black in colour in a large mass, but appear brown in thin films.
A mixture of tar and bitumen provides a binder of excellent quality as it has a decreased volume of insoluble benzene is decreased. Such mixtures have lower temperature susceptibility and reduced penetration value. Rheological properties of the binder also get altered. Generally, a mixture of tar and bitumen in equal proportions is considered to be an ideal binder.
Bituminous mixes for paving purposes consist of coarse aggregate, fine aggregate, filler material, bitumen, and air voids, suitably proportional and blended to provide a strong, stable and durable pavement.
The main aim of mix design is to determine the optimum bitumen content that will hold the mineral aggregates of suitable gradation together as a compact layer that resists the traffic loads. The mix should have a certain minimum air voids to allow volume changes during service either because of temperature changes or repeated loading from the traffic.
Requirements of Bituminous Mixes:
The following are the important requirements of bituminous mixes for pavements:
This is the resistance to deformation under traffic loads it is a function of inter- particle friction and cohesion offered by the bitumen binder. It is related to the density of the mix which is dependent on the voids content. The more the density, the more stable the mix however, a minimum voids content is necessary to allow for volume changes which cannot be fully prevented.
This is the resistance to weathering action and abrasion from traffic. Spalling, stripping and formation of pits, corrugations and potholes can result from weathering and traffic. Excessive strain may cause cracking or plastic failure.
This is a measure of the resistance to long-term deformations and shapes of the road base, sub-base and subgrade this depends on the flexural or bending strength of the pavement.
The resistance of the surface of the pavement laid with the bituminous mix to skidding of the tyres of vehicles is called skid resistance. The surface texture should be such as to provide grip or friction even under wet conditions. This is important in the prevention of accidents.
This is the ease with which the mix can be placed in position and compacted. It depends on the aggregate characteristics like the size, shape texture and gradation, bitumen content and nature of the bituminous material.
The overall cost in achieving the desired qualities of the mix and the pavement should be a minimum, consistent with quality.
The desired qualities of the bituminous mixes, therefore, have to be achieved by:
1. Using good quality aggregate, which is hydrophobic and has rough surface texture, with appropriate grading and voids content.
2. Using bituminous binder of the correct quality and consistency based on the specific purpose for which the pairing mix is intended.
3. Controlling the voids content and the bitumen content to achieve the desirable qualities listed above.
4. Cement, Cement Mortar and Cement Concrete :
Cement concrete is a versatile material which has revolutionised civil engineering construction during the twentieth century. A fresh cement concrete mix consists of cement, mineral aggregates (coarse aggregate and fine aggregate), and water.
A well-designed cement concrete mix sets and hardens due to the binding property of the cements, forms a mix with minimum void space and on curing with water, provides a strong, stable and durable pavement for a highway, resisting repetitive impact from wheel loads and also withstanding adverse environmental conditions.
Thus, a cement concrete pavement is the most superior highway construction primarily from the point of view of strength and durability. The ingredients of the concrete mix, viz., the coarse aggregate (broken stone) and fine aggregate (sand) have to be selected carefully to satisfy the desirable properties for concrete-making. Potable water is generally considered satisfactory making cement concrete.
Cement is used also as an additive to soil to produce soil-cement used as the primarily material in the construction of low-cost roads.
Cement is the most important ingredient of cement concrete or cement mortar (cement mortar is a suitable mixture of cement and fine aggregate or sand in appropriate proportions).
Cement mixed with water becomes a paste and spreads over the aggregates forming a thin film chemical reactions take place leading to the formation of silicates and aluminates. Subsequently, setting takes place and in the presence of water, hydration takes place leading to hardening of the concrete.
The most common cement is what is now known as the Ordinary Portland Cement (OPC). Calcareous and silicate compounds are blended and heated to high temperatures (1500°C) to form clinkers of new chemical compounds, which when ground to fine particles result in ‘cement’.
The primary ingredients of cement are:
(i) Tricalcium silicate (3CaO.SiO2) ≈ 50%
(ii) Dicalcium silicate (2CaO.SiO2) ≈ 22%
(iii) Tricalcium aluminate (3CaO.Al2O3) ≈ 9%
(v) Miscellaneous compounds ≈ 10%
The silicates contribute to the immediate strength gain while the other ingredients are responsible for the long-term strength gain. The properties of cement can be modified by blending it in different admixtures in the manufacturing process.
The following are the different types cements widely used for specific purposes in India:
1. Ordinary Portland cement (OPC)
5. Portland blast furnace slag cement
Ordinary Portland cement is classified into three grades:
Grade 43 cement is widely used for highway pavements since its heat of hydration and shrinkage cracks are less compared to OPC 53 grade.
Rapid hardening cement is preferred for remedial jobs when rapid gain of strength is necessary to restore the pavement to traffic in a short duration.
The important properties of cement are:
This is related to grain size and specific surface. Fineness is a desirable feature because it is related to the intensity of hydration and strength gain. Sieve analysis is the simplest and the most direct method to determine the fineness (IS: 269-1993). Dry cement retained on IS-90 p sieve should not be more than 10% for OPC and 5% for rapid-hardening cement.
Workable cement mortar paste using a desired water-cement ratio is prepared and the time taken for the paste to harden is noted setting time is an indication of initial chemical reactions of cement.
Temperature and humidity affect setting time. The standard values for testing are 20±2°C and 65% respectively. Setting times are classified into initial and final setting time. Initial setting time is important for transporting, placing and compaction of concrete. The minimum initial setting time for OPC should be at least 30 min. (IS: 269-1993).
The final setting time is the time required for the concrete to harden sufficiently to attain the shape of the mould in which it is poured. By this time, primary chemical reactions are completed. This is important for the removal of form work. The maximum final setting time is about 10 hours for OPC (IS: 269-1993).
This is the ability to resist volume changes as a result of the channel reactions with water. The Le Chatelier test and the autoclave test are used to verify the soundness (IS: 269-1993).
4. Chemical Composition:
The lime saturation factor (LSF) of a cement is the ratio of Calcium Oxide (CaO) to the other three main oxides present in it.
This is usually determined by testing cement mortar or cement concrete cubes or cylinders for compression, tension and flexural strength. Compressive strength is the most important property for OPC, it should not be less than 16, 22 and 33 MPa at 3, 7 and 28 days of curing (IS: 269-1993).
Admixtures for Cement Concrete:
Different types of additives — chemical compounds, synthetic polymers and resins are blended with cement concrete while mixing, to modify its properties. Setting times, workability, strength and durability can be modified by reducing water and cement and adding admixtures. (IS: 9103 and IS: 6925)
Some admixtures used are:
1. Retardants – Increase the setting time of cement concrete.
2. Accelerators – Accelerate hydration for rapid strength gain.
3. Plasticisers and super-plasticisers – Increase the workability of concrete, reduce the water content needs and reduce the heat of hydration
4. Air-entraining agents – Improve workability and increase resistance to frost action.
5. Pigments – Impart colour to the cement concrete mix for aesthetic purposes.
Fly ash, blast furnace slag, pond ash, rice husk ash, calcined clay and other mineral additives supplement cementing properties, and act as partial substitutes for cement for achieving some degree of economy.
This is a property of fresh concrete. The ease of placement is workability. Slump test and compaction factor test are generally used to assess the workability of concrete (SP: 23-1982). Generally, ‘slump’ ranges from 25 to 125 mm. The prescribed compaction factor values are of the order 0.75 to 0.80 (IS: 456-2000 & IS: 1199-1959)
Tests on hardened concrete are for compressive strength, flexural strength, split (or indirect) tensile strength and elastic modulus [IS: 516-1999 & IS: 5816-1999].
The Poisson’s ratio for normal concrete in Indian conditions may be taken as 0.15. More details may be found in the relevant Indian Standard Specifications cited.
ICSE Geography Question Paper 2015 Solved for Class 10
ICSE Paper 2015
Answers to this Paper must be written on the paper provided separately.
You will not be allowed to write during the first 15 minutes.
This time is to be spent in reading the question paper.
The time given at the head of this Paper is the time allowed for writing the answers.
Attempt seven questions in all.
Part I is compulsory. All questions from Part I are to be attempted.
A total of five questions are to be attempted from Part II.
The intended marks for questions or parts of questions are given in brackets [ ].
To be supplied with this Paper : Survey of India Map Sheet No. 45D/10
and 20 cm of twine.
(i) In all Map Work, make wise use of arrows to avoid overcrowding of the map.
(ii) The extract of Survey of India Map Sheet No. 45D/10 must not be taken out of the examination hall. It must be handed over to the Supervising Examiner on completion of the Paper.
(iii) The Map given at the end of this question paper must be detached, and after marking must be fastened to your answer booklet.
(iv) All sub-sections of the questions attempted must be answered in the correct serial
(v) All working including rough work should be done on the same answer sheet which is used to answer the rest of the paper.
Attempt all questions from this Part.
Study the extract of the Survey of India Map Sheet No. 45D/10 and answer the following questions :
(a) Give the four figure grid reference for a figure similar to the one given below. Identify the figure: 
(b) How is the drainage pattern in grid square 1606 different from that in grid square 1608? 
(c) Identify the correct six figure grid reference for each of the following:
(i) Gautam Maharishi Mandir
200071 071200 201070 ?
172059 052179 179052 ? 
(d) Name the most prominent settlement other than ABU. Give two reasons to support your answer. 
(e) (i) What is the general slope of the land in the north-west comer of the map extract ?
(ii) What is the compass direction of Chandela (1803) from Hanumanji ka Mandir (2208) ? 
(f) What do you understand by the following terms as used on the map extract :
(i) Causeway (1702)
(ii) Falls 25m (2307). 
(g) (i) If you were to cycle at 10 km an hour, how much time would it take to cover the north-south distance depicted on this map extract ?
(ii) Calculate the area enclosed by Eastings 19 to 22 and Northings 04 to 09. 
(h) (i) Identify one natural feature in grid square 1610
(ii) Identify one man made feature in grid square 1903. 
(i) Give two probable reasons, other than dry water features, to indicate that the region depicted on the map extract receives seasonal rainfall. 
(j) Calculate, in metres, the difference in height between the highest point on the map extract and the contour height given in grid square 2402. 
(a) The four fig grid reference for the figure is 1903. And the figure is a seasonal tank with an embankment.
(b) Drainage pattern of grid square 1606 is Radial and of grid square 1608 is Trellis.
(c) The correct six figure are
(i) Gautam Maharishi Mandir-200071.
(d) Vajna settlement is another prominent settlement because
(1) It has a police Chauki.
(2) It is located on the metalled road therefore good transport is available.
(e) (i) General slope of the land in the North west comer is towards North west.
(ii) Compass direction of Chandela from Hanumanji Ka Mandir is South west.
(f) (i) Cause way : It is a raised road or path that enable us to cross a seasonal river. It does not work during rain. It is not a bridge.
(ii) Fall 25 m indicate the presence of a waterfall i.e., 25 metres high.
(g) (i) one hour.
(ii) Area = L × B = 3 × 5 = 15 km 2
(h) (i) Natural feature in 1610 is broken ground and seasonal stream.
(ii) One man made feature in grid square 1903 is hut and embankment.
(i) Two reasons to indicate that the region depicted on the map receives seasonal rainfall are :
(j) Difference between the highest point on the map and the contour height given in grid square 2402 is 1129 metres.
On the outline map of India provided :
(a) Mark and. name the Nilgiris. 
(b) Shade and label the Malwa Plateau. 
(c) Shade and label the Malabar Coastal Plains. 
(d) Mark and name the river Gomti. 
(e) Shade and name the Andaman Sea. 
(f) Mark and name Allahabad. 
(g) Mark with a single arrow and name the winds that bring winter rain to north-west India. 
(h) Mark and name Digboi. 
(i) Mark an area with laterite soil below the Tropic of Cancer. 
(j) Mark and name the Karakoram Pass. 
Attempt any five questions from this Part.
(a) Explain two factors that affect the climate of India giving a suitable example for each. 
(b) State two differences between the rainfalls that occur from June to September and that from December to February in North India. 
(c) Give a geographic reason for each of the following :
(i) Kerala has the longest rainy season.
(ii) The Konkan coast experiences orographic rainfall.
(iii) The city of Kanpur in Uttar Pradesh has a higher range of temperature than that of Chennai in Tamil Nadu. 
(d) Study the climatic data given below and answer the questions that follow :
Month JAN FEB MAR APR MAY JUN JUL AUG SEP OCT NOV DEC Temp °C 21.0 21.9 24.3- 27.2 28.0 26.4 26.1 25.4 25.0 26.0 23.8 21.2 Rainfall Cm 5.1 2.8 1.2 1.7 3.9 4.6 8.4 11.4 11.9 31.6 34.5 14.8
(i) Identify the hottest month.
(ii) Calculate the annual rainfall.
(iii) Name the winds that bring the maximum rainfall to this city. 
(a) Two factors that affect the climate in India are :
- Altitude: As the height increases temperature decreases at the rate of 1°C for every 165 m of ascend. Example : Nainital has lower temperature than Agra.
- Distance from the sea: Places close to the sea have lower range of temperature i.e. moderate climate and places away from the influence of the sea have higher range of temperature i.e. continental climate. Example : Mumbai has lower range of temperature than Delhi as it is close to the sea.
(b) Two differences between the rainfall that occur from June to September and from December to February are :
- Rainfall in June to September is caused by S.W. monsoon whereas rainfall in December to February is caused by temperate cyclones (western disturbances) originating in Mediterranean sea.
- Rain in June to September is heavy ranging between 75 to 150 cm. whereas rain in Dec. to February is only 5 to 7 cm but beneficial for wheat and barley.
(c) Geographical Reasons:
(i) Kerala has the longest rainy season because it lies in the extreme south of India and it is the first and last to see the monsoon.
(ii) Konkan coast experiences orographic rainfall because it lies of the wind ward side of western ghats when south west monsoon strikes it.
(iii) Kanpur in Uttar Pradesh has a higher range of temperature than that of Chennai because Kanpur is located away from the sea and the equator.
(d) (i) May is the hottest month.
(ii) Annual rainfall is 131.9 cm.
(iii) Maximum rainfall is received by North-East monsoon winds.
(a) State the characteristic of each of the soils named below that makes them most suitable for crop cultivation :
(i) Black soil.
(ii) Red soil. 
(b) State the geographic term for each of the following processes :
(i) The process by which soluble minerals dissolve in rain water and percolate to the bottom, leaving the top soil infertile.
(ii) The process by which rain water, flowing in definite paths, removes the top soil, thus causing deep cuts to the surface of the land. 
(c) Define the following :
(iii) Bhangar. 
(d) Give a geographic reason for each of the following :
(i) Alluvial soil is extremely fertile.
(ii) Need for soil conservation.
(iii) Reafforestation should be practised extensively. 
(a) (i) Characteristic of black soil : It is able to retain moisture.
(ii) Characteristic of red soil : It is rich in potash and become fertile with proper use of fertilizers and irrigation.
(b) Geographic terms are :
(ii) Gully erosion.
(i) Pedogenesis: Process of soil formation is called pedogenesis.
(ii) Humus: Decayed remains of plants, animal manures and dead animals is called Humus. It is an essential element in determining the fertility of soil.
(iii) Bhangar: Older alluvium soil found about 30 m above sea level in river terraces, light grey in colour and calcareous clay is called humus.
(d) Geographical reasons:
(i) Alluvial soil is extremely fertile because it is found to a depth of 500 m and rich in humus, lime and potash.
(ii) There is a need for soil conservation because top soil that is eroded is the main feeding zone. With the increase in population the demand of crops is also increasing.
(iii) Reafforestation should be practised extensively because the area under forest cover is shrinking day by day due to urbanization etc.
(a) State two characteristics of Tropical Deciduous forests. 
(b) State two reasons why Tropical Evergreen forests are difficult to exploit. 
(c) Identify the tree as per its characteristics mentioned below :
(i) It yields wood that is hard and scented and is usually found in high altitudes.
(ii) It is generally found in deltaic regions and is used to make boats.
(iii) The furniture made from the wood of this tree is generally the most expensive. 
(d) Differentiate between afforestation and deforestation. State a disadvantage of deforestation. 
(a) Characteristics of Tropical deciduous forests are :
(i) They shed their leaves before the summer season.
(ii) These trees are found in pure stands.
(b) Tropical evergreen forests are difficult to exploit because they are found in mixed stands and found in dense growth.
(c) Trees as per its characteristics are :
(d) Afforestation means growing of trees where there are no trees. It increases the forested area.
Deforestation means cutting of trees for various purposes.
Disadvantage : It increases soil erosion.
(a) State two reasons why’irrigation is important to a country like India. 
(b) Name two modern methods of irrigation. State one important reason for their growing popularity. 
(c) (i) Why is well irrigation still a popular means of irrigation ? Give two reasons to support your answer.
(ii) State the significance of rainwater harvesting. 
(d) (i) Why is the world in danger of facing a severe water shortage in the coming future ? Give two reasons to support your answer.
(ii) State one measure the Government should adopt to handle the present water crisis. 
(a) Irrigation is important to a country like India because rainfall here is seasonal in nature. It is limited to four months of a year. It is also important because some crops require more water than what it is provided by the rainfall therefore we have to depend on irrigation.
(b) Two modern methods of irrigation are :
They are becoming popular because there is minimum loss of water and can irrigate fields throughout the year.
(c) (i) Well irrigation is still a popular means of irrigation because :
- It can supply water whenever and where ever required.
- It is also a cheap source of irrigation.
(ii) Significance of rain water harvesting are :
(i) Reduce surface run off therefore no flooding of roads.
(ii) It raises ground water table by adding to ground water reserves.
(iii) It solve the problem of water scarcity.
(d) (i) The world is in danger of facing a severe water shortage in coming future because :
- Most of our surface waters are polluted by industrial waste, sewage etc.
- The indiscriminate use of chemicals, fertilizers, pesticides, insecticides, to increase farm productions had led to increasing ground water pollution.
(ii) One measure the Government should adopt to handle present water crisis is rain water harvesting and recycle and reuse of water.
(a) State two reasons why limestone is a valuable mineral. 
(b) State the most important use of the following :
(i) Iron ore
(ii) Bauxite 
(c) Name the :
(i) Largest oil refinery in the Public sector.
(ii) State that is the largest producer of coal.
(iii) Best variety of iron ore. 
(d) Give a geographic reason for each of the following :
(i) Many port cities have their own oil refineries.
(ii) Petroleum is called a ‘fossil fuel’.
(iii) Coal is called a versatile mineral. 
(a) Limestone is a valuable mineral because it is used in various industries like chemicals, iron and steel, cement, fertilizers etc.
(b) Most important use of:
(i) Iron ore : In the production of steel.
(ii) Bauxite: In the production of aluminium.
(c) (i) Largest oil refinery in the public sector — Indian Oil Corporation Ltd.
(ii) Jharkhand is the largest coal producing state.
(iii) Hematite is the best variety of iron ore.
(d) Geographical reasons for the following are :
(i) Port cities have their own oil refineries because two thirds of the petroleum is imported. The crude oil is imported from Gulf countries and Malaysia.
(ii) Petroleum is called fossil fuel because it is derived from plant and animal . life buried in sedimentary rocks millions of years ago.
(iii) Coal is called a versatile mineral because it forms a basic raw material for the production of chemicals, dyes, fertilizers, paints, synthetics, explosive apart from source of energy.
(a) Differentiate between a Rabi crop and a Kharif crop. 
(b) State an important difference between the climatic requirements for growing cotton and jute. 
(c) Give the geographic term for each of the following :
(i) Cultivation of sugarcane from the root stock of the cane which has been cut.
(ii) The residue left behind after the crushing of oilseeds.
(iii) The process by which latex is converted into a thick, spongy mass by adding acetic acid or formic acid. 
(d) Give a geographical reason for each of the following :
(i) Tea is cultivated on hill slopes.
(ii) The yield per hectare of sugarcane is higher in the Southern states.
(iii) Pulses are important food crops. 
(a) Rabi crop is sown during late November and harvested in March e.g. : wheat, mustard etc.
Kharif crop is sown in June and harvested in early November e.g. : rice, cotton etc.
(b) Climatic requirements for growing cotton :
Temperature: 20°C to 32°C and atleast 200 frost free days.
Rainfall: Ranging between 50 cm to 120 cm abundant sunshine is required during ripening period.
Climatic requirement for Jute :
Temperature: 21°C to 35°C a hot climate with high atmospheric humidity. Rainfall : Ranging between 150 cm to 200 cm.
(c) Geographical terms are :
(i) Ratoon crop
(ii) Oil cake
(d) Geographical reasons are :
(i) Tea is cultivated on hill slopes because tea plant can not tolerate standing water on its roots.
(ii) Yield per hectare of sugarcane is higher in southern states because of the use of modem scientific agricultural methods and the factories are located close to the fields.
(iii) Pulses are important food crops because they are rich source of protein for vegetarian people.
(a) (i) Why is the cotton textile industry called an agro-based industry ?
(ii) Give an important reason for it being more widespread than the jute industry. 
(b) (i) State one important point of similarity between the woollen industry and the silk industry.
(ii) Name the state that produces the most woollen and silk products respectively. 
(c) (i) State two major problems faced by the sugar industry.
(ii) Name two by-products of the sugar industry. 
(d) (i) State one of the main problems of the silk industry.
(ii) Name two products of the jute industry, other than rope and gunny bags.
(iii) Why are synthetic fibres popular ? 
(a) (i) Cotton textile is called an agro-based industry because for its raw material it depends on cotton which is an agricultural product.
(ii) It is more widespread than the jute industry because India has tropical climate where cotton is mainly used for clothing.
(b) (i) Main similarity between the woollen and the silk industry : Both of them derive their raw material from animals and both require skilled labour.
(ii) State that produces woollen products is Punjab and state that produces silk products is Karnataka.
(c) (i) Two problems faced by sugar industry are :
(1) It is the most soil exhausting crop therefore cost increases.
(2) Sugar mills are old-fashioned and far from the sugar farms.
(ii) Two by products of the sugar industry are :
(d) (i) One main problem of the silk industry is that it has a limited market as it is very expensive.
(ii) Two products of the jute industry are upholstry and carpets.
(iii) Synthetic fibres are popular because they are cheap, durable and easy to maintain.
(a) (i) Why is the iron and steel industry called a basic industry ?
(ii) Define a mini steel plant. 
(b) With which large scale industry would you identify the following manufacturing centres :
(iv) Mangalore. 
(c) (i) State two reasons for the growing importance in the status of petrochemical industries.
(ii) Name two products of the petroleum industry. 
(d) (i) State two conditions necessary for the setting up of a heavy engineering industry.
(ii) Name a ship building yard on the east coast and a centre for making electric locomotives. 
(a) (i) Iron and steel industry is called basic industry because it supports fertilizers and cement industry. It is linked with the economic development of a country.
(ii) Mini steel plant is a unit that uses cheaply available scrap iron in the electric arc furnaces to make steel which is futher rolled and shaped into necessary products.
(b) Large scale industry that we identify with :
(i) Kanpur : Woollen industry.
(ii) Rourkela : Iron and Steel plant.
(iii) Pune : Electronics Industry.
(iv) Mangalore : Petrochemical Industry.
(c) (i) Two reasons for the growing importance is the status of petrochemical, industries are :
- It is durable, cheap, light weight and attractive.
- It has replaced wood, glass, metal, natural rubber etc.
(ii) Two products of the petroleum industry are :
(d) (i) Two conditions necessary for the setting up of a heavy engineering industry are :
(ii) Ship building yard on east coast is Vishakhapatnam and Chittaranjan for making electric locomotives.
(a) (i) Why is the Railways an important means of transport as compared to Airways ?
(ii) State one economic benefit of the Golden Quadrilateral Project. 
(b) (i) State one important difference between an expressway and a highway.
(ii) Name the first expressway constructed in the country.
(iii) State a reason why the Northern Rivers are more suitable for navigation than the Deccan Rivers. 
(c) (i) “Waste segregation is important”. Give a reason to support your answer.
(ii) Why is nuclear waste harmful ?
(iii) Explain briefly how as a student, you can help in the reduction of waste generation. 
(d) (i) What is understood by biodegradable waste ?
(ii) State one source of gaseous waste. 
(a) (i) Railways is an important means of transport as compared to airways as it is cheap and has more carrying capacity of passengers and goods.
(ii) Economic benefit of the Golden Quadrilateral project is that it leads to general improvement of the area with more employment.
(b) (i) Expressway is a six lane highway where two and three wheelers are not allowed. A highway is a two lane road where all vehicles are allowed.
(ii) Mumbai-Pune expressway is the first expressway constructed in the country.
(iii) Northern Rivers are more suitable for navigation than the Deccan Rivers because they are perennial in nature and flow over gentle sloping plains.
(c) (i) Waste segregation is important because the method of treating waste depends on the nature of waste like solid waste, liquid waste, biodegradable and non-biodegradable waste.
(ii) Nuclear waste is more harmful because radioactive wastes remain active for a long time therefore it can enter in human body through food and water and can cause damage of tissues, blood cells and cancer.
(iii) As a student I can segregate the waste into biodegradable and non biodegradable waste of my house, reduce the water by incineration and recycling it.
(d) (i) Biodegradable waste is a type of waste which can be broken down in a reasonable amount of time, into its base compounds by micro organisms and other living things regardless of what those compounds may be.
(ii) Release of smoke, ashes and aerosols from chimneys of factories, increase CO2. Methane comes out from cattle shed. Swamps, coal mines etc. Volcanic erruptions gives out SO2.
Check Out These Popular Flowers In Hawaii
Few flowers hold the allure of Hawai’i more than the plumeria. The huge varieties found throughout the islands make it seem as though they originated here, but in truth they are an introduced species. First discovered in the southern forest regions of Mexico in the mid 1800’s, the plant is also known to indigenous to Central America, India, the Caribbean and Brazil.
The first plants were brought to Hawai’i in 1860 by Wilhelm Hillebrand, a German physician and botanist. In Hawai’i the plant usually grows as a small tree that mostly blooms from April to November. Flowers do not last long but the bloom pod can produce flowers throughout the year depending on climate and location. The flower colors are diverse in Maui and include white, orange, yellow, pink, salmon, and purple with hybrids containing combinations of all these colors. Plumeria have an amazing fragrance that is most intense at night as they lure moths needed to pollinate them. Interestingly enough they produce no nectar, effectively duping the pollinators to move from flower to flower in a fruitless search for nectar.
The flowers are well known for their use in making flower lei. These beautiful and fragrant flowers can also be worn in the hair by women to indicate their relationship status – over the right ear if single and over the left ear if taken.
Plumeria are used in lei making across much of the south Pacific including Tahiti, Fiji, Samoa, New Zealand, Tonga and the Cook Islands.
According to the American Plumeria society of Florida there are more than 300 named varieties of Plumeria across the world .
In India, the tropical plants were known as temple trees. Buddhists said they resembled immortality because you can snap a branch off and it will re-grow and produce beautiful flowers from the severed branch. Hindus offered the beautiful tropical flowers to their gods. In other cultures, like Bengali, the white Plumerias were associated with funerals or death.
Aztec Indians used Plumeria for medical purposes.
Caribbean’s use the leaves as a wrap to heal bruises.
In the Philippines or Indonesia, you may find these flowers in graveyards because of the belief that the tropical plant would shelter ghosts.
Bird of Paradise
You’ll see these everywhere on Maui. They are typically found in bouquets and floral arrangements seen placed in the entrances, sitting areas and deluxe rooms of larger resorts and hotels. It is also commonly found in local Hawaiian landscaping located at warm, dry sea level areas like Kihei and Lahaina. It’s long stems suspend the blossoms 3 to 4 feet into the air. They have no smell and last for as much as a week or more after being cut.
Blue & Purple Wildflowers
Scientific name: Iris missouriensis
Family: Iris family (Iridaceae)
Habitat: Found in moist montane meadows.
These showy light blue to lilac colored flowers have petals streaked with dark purple veins and with yellowish white bases. They bloom from late May to early July. The name Iris comes from the Greek, for the rainbow who was the winged messenger of the gods the flower was named for the rainbow's colorful cloak.
Scientific name: Monarda fistulosa var. menthifolia
Family: Mint family (Lamiaceae)
Habitat: Grows in clusters in sunny montane areas.
The purplish rose flowers grow in dense heads at the tops of 1 to 3 ft (40-100 cm) stems. Because of its spicy aroma, the plant is also known as wild oregano.
Scientific name: Aquilegia coerulea
Family: Hellebore family (Helleboraceae)
Habitat: It can be found growing in shaded montane and subalpine forests, as well as rocky alpine sites.
Colorado columbine is the state flower of Colorado. The petals are drawn out into long spurs between the sepals. The spurs contain nectar, which attracts butterflies and long tongued bees. Colorado columbine begins blooming in June at lower elevations through August in alpine areas.
Scientific name: Lupinus argenteus
Family: Pea family (Fabaceae)
Habitat: Grows in dry montane to subalpine areas
Mountain lupine can reach a height of 1 to 3 ft. (40-100cm). The color of the petals can vary from creamy white to blue. The leaves are palmately compound with five or more leaflets.
Scientific name: Phacelia sericea
Family: Waterleaf family (Hydrophyllaceae)
Habitat: Dry rocky montane to subalpine
Purple-fringe typically has many stems, each with a dense cluster of flowers. The flowers are deep purple. Yellow tipped stamens project from each flower, giving the clusters a fringed appearance. Purple fringe blooms from early June to early August.
Scientific name: Erigeron speciosus
Family: Aster family (Asteraceae)
Habitat: Wet meadows, aspen groves and conifer forests from montane to subalpine areas.
This common daisy has light blue to lavender (sometimes white) ray flowers. The leaves are hairless except on the veins. It blooms from mid July to August.
Pasqueflower and inset photo of Pasquefllower without pedals just feathery stamens
NPS photo by A. Schonlau
Inset NPS photo by D. Biddle
Scientific name: Pulsatilla patens
Family: Buttercup family (Ranunculaceae)
Habitat: Well-drained open slopes from montane to tree line
One of the earliest flowers to bloom, Pasqueflowers begin blooming as early as March in lower montane areas and can be seen through July at treeline. The large flowers have lavender tepals (petals and sepals that look alike) and bloom before the leaves develop. After the tepals drop, the flowers appear as feathery plumed heads due to the elongated styles.
Scientific name: Aconitum columbianum
Family: Hellebore family (Helleboraceae)
Habitat: Wet montane to subalpine areas
Monkshood is a tall plant with stems up to 57 inches (150 cm) tall. The flowers resemble larkspur except that Monkshood's upper sepal resembles a helmet or hood rather than a spur. Monkshood has two color forms, which are both found in the park – a deep blue- purple form and a greenish-yellow form. It blooms from late June to late August.
Scientific name: Campanula rotundifolia
Family: Bellflower family (Campanulaceae)
Habitat: Montane to alpine meadows and aspen groves.
This plant has many slender stems, each bearing several bell shaped blue flowers. It blooms from late June into early October. This plant grows in mountainous areas around the world, and is also known as the bluebell-of-Scotland.
Scientific name: Mertensia ciliata
Family: Borage Family (Boraginaceae)
Habitat: Abundant alongside subalpine and lower alpine streams and drainages.
Clusters of bell-shaped flowers grow on stems 8 to 31 inches tall (20-80cm). The flower buds are pinkish to lavender, changing to blue when the flowers open. This color change alerts bees that flowers are ripe for pollination. Tall chimingbells bloom from mid-June to mid-August.
Scientific name: Eritrichum aretioides
Family: Borage Family (Boraginaceae)
Habitat: Open rocky alpine slopes and dry meadows.
Alpine forget-me-not is one of the first to bloom on the tundra, usually appearing from late May to early July. Several flowers cover a tiny compact cushion plant, with each stem typically less than an inch tall (rarely up to 3 inches (7 cm). The fragrant flowers have dark blue to purple petals with a yellow central ring.
Scientific name: Polemonium viscosum
Family: Phlox Family (Polemoniaceae)
Habitat: Rocky alpine areas.
These eye-catching clusters of flowers are a purplish blue with bright yellow anthers. The flowers smell either sweet or skunky with sweeter flowers generally found at higher elevations. Growing on stems up to 4 inches (10 cm) tall, sky pilots bloom from June to early August.
Watch the video: Το φυτό χαμαιλέοντας - What the Fact?! #43 (November 2022).