University of Utah electrical engineers fabricated the smallest plasma transistors that can withstand high temperatures and ionizing radiation found in a nuclear reactor. Such transistors someday might enable smartphones that take and collect medical X-rays on a battlefield, and devices to measure air quality in real time.

"These plasma-based electronics can be used to control and guide robots to conduct tasks inside the nuclear reactor," says Massood Tabib-Azar, a professor of electrical and computer engineering. "Microplasma transistors in a circuit can also control nuclear reactors if something goes wrong, and also could work in the event of nuclear attack."

A study of the new transistors by Tabib-Azar and electrical engineering doctoral student Pradeep Pai appears online Thursday, March 20 in the journal IEEE Electron Device Letters, published by the Institute of Electrical and Electronics Engineers. The study was funded by the Defense Advanced Research Projects Agency.

Transistors are the workhorses of the electronics industry. They control how electricity flows in devices and act as a switch or gate for electronic signals. Billions of transistors are typically fabricated as individual but connected components on a single computer chip. The most commonly used type of transistor is called a metal oxide semiconductor field effect transistor, or MOSFET.

Transistors control the flow of electrical charge through a silicon channel using an electric field to turn the transistor on or off, similar to a valve with the electric field as its control knob and electric charge as its current flow. Silicon-based transistors are a crucial component in modern electronics, but they fail above 550 degrees Fahrenheit -- the temperature at which nuclear reactors typically operate.

Plasma-based transistors, which use charged gases or plasma to conduct electricity at extremely high temperatures, are employed currently in light sources, medical instruments and certain displays under direct sunlight (but not plasma TVs, which are different). These microscale devices are about 500 microns long, or roughly the width of five human hairs. They operate at more than 300 volts, requiring special high-voltage sources. Standard electrical outlets in the United States operate at 110 volts.

The new devices designed by the University of Utah engineers are the smallest microscale plasma transistors to date. They measure 1 micron to 6 microns in length, or as much as 500 times smaller than current state-of-the-art microplasma devices, and operate at one-sixth the voltage. They also can operate at temperatures up to 1,450 degrees Fahrenheit. Since nuclear radiation ionizes gases into plasma, this extreme environment makes it easier for plasma devices to operate.

"Plasmas are great for extreme environments because they are based on gases such as helium, argon and neon that can withstand high temperatures," says Tabib-Azar. "This transistor has the potential to start a new class of electronic devices that are happy to work in a nuclear environment."

A conventional transistor is made with two active layers, one on top of the other. Electricity flows through one of the layers, called the channel. The other layer, called the gate, controls current flowing in the channel. If sufficient voltage is applied to the gate, the transistor turns on.

For the new study, Tabib-Azar and Pai deposited layers of a metal alloy to form the gate on a 4-inch glass wafer. A layer of silicon then was deposited on top of the gate.

Unlike typical transistors, the Utah microplasma transistor "channel" is an air gap that conducts ions and electrons from the plasma once a voltage is applied. To achieve this unique design, the team etched away portions of the silicon film using a chemically reactive gas. This etching process leaves behind cavities and empty spaces to form the transistor's channel and expose the gate underneath. The channel tested in this new study was 2 microns wide and 10 microns long, and helium was used as the plasma source.

"Although the length scales are much smaller here, we came up with an innovative way to make these structures three-dimensional," Tabib-Azar says. "We are currently connecting these devices to form logic gates and computing circuits that we will test in our experimental nuclear reactor at the University of Utah, a facility not found in most other universities."

Traditional MOSFETs require metal to connect circuits, says Tabib-Azar, but the Utah microplasma devices will use a plasma-based connection to enable communication. As a result, these circuits will only be operational when powered up and will disappear otherwise, making them suitable for defense applications.

These plasma devices could also be used as an X-ray imaging source in the next five years, says Tabib-Azar. Because the device dimensions are so small, X-ray images from a wounded soldier in the field could be collected on a smartphone equipped with transistors that also generate the X-rays, says Tabib-Azar.

In another five years, the devices could be used to detect and identify aerosol pollutants based on the color emitted when the substance passes through the device. "These chemical sensing devices could be used to quantitatively monitor air quality in real time and enable researchers to construct an accurate air-quality map," he adds.

In the nearer-term, these new transistors could be used to generate X-rays to draw fine lines in silicon to pattern microscale devices for the electronics industry. With this new X-ray technique, Tabib-Azar says, "you can do the same thing you would with laser printing, but instead you can use these tiny X-ray sources to print on a silicon wafer. This gives engineers the ability to do X-ray lithography without having to use very heavy lenses and X-ray beam shaping devices.
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Generating electricity is not the only way to turn sunlight into energy we can use on demand. The sun can also drive reactions to create chemical fuels, such as hydrogen, that can in turn power cars, trucks and trains.

The trouble with solar fuel production is the cost of producing the sun-capturing semiconductors and the catalysts to generate fuel. The most efficient materials are far too expensive to produce fuel at a price that can compete with gasoline.

"In order to make commercially viable devices for solar fuel roduction, the material and the processing costs should be reduced significantly while achieving a high solar-to-fuel conversion efficiency," says Kyoung-Shin Choi, a chemistry professor at the University of Wisconsin-Madison.

In a study published last week in the journal Science, Choi and postdoctoral researcher Tae Woo Kim combined cheap, oxide-based materials to split water into hydrogen and oxygen gases using solar energy with a solar-to-hydrogen conversion efficiency of 1.7 percent, the highest reported for any oxide-based photoelectrode system.

Choi created solar cells from bismuth vanadate using electrodeposition -- the same process employed to make gold-plated jewelry or surface-coat car bodies -- to boost the compound's surface area to a remarkable 32 square meters for each gram.

"Without fancy equipment, high temperature or high pressure, we made a nanoporous semiconductor of very tiny particles that have a high surface area," says Choi, whose work is supported by the National Science Foundation. "More surface area means more contact area with water, and, therefore, more efficient water splitting."

Bismuth vanadate needs a hand in speeding the reaction that produces fuel, and that's where the paired catalysts come in.

While there are many research groups working on the development of photoelectric semiconductors, and many working on the development of water-splitting catalysts, according to Choi, the semiconductor-catalyst junction gets relatively little attention.

"The problem is, in the end you have to put them together," she says. "Even if you have the best semiconductor in the world and the best catalyst in the world, their overall efficiency can be limited by the semiconductor-catalyst interface."

Choi and Kim exploited a pair of cheap and somewhat flawed catalysts -- iron oxide and nickel oxide -- by stacking them on the bismuth vanadate to take advantage of their relative strengths.

"Since no one catalyst can make a good interface with both the semiconductor and the water that is our reactant, we choose to split that work into two parts," Choi says. "The iron oxide makes a good junction with bismuth vanadate, and the nickel oxide makes a good catalytic interface with water. So we use them together."

The dual-layer catalyst design enabled simultaneous optimization of semiconductor-catalyst junction and catalyst-water junction.

"Combining this cheap catalyst duo with our nanoporous high surface area semiconductor electrode resulted in the construction of an inexpensive all oxide-based photoelectrode system with a record high efficiency," Choi says.

She expects the basic work done to prove the efficiency enhancement by nanoporous bismuth vanadate electrode and dual catalyst layers will provide labs around the world with fodder for leaps forward.

"Other researchers studying different types of semiconductors or different types of catalysts can start to use this approach to identify which combinations of materials can be even more efficient," says Choi, whose lab is already tweaking their design. "Which some engineering, the efficiency we achieved could be further improved very fast.

Space rocks hitting Mars excavate fresh craters at a pace of more than 200 per year, but few new Mars scars pack as much visual punch as one seen in a NASA image released Feb. 5, 2014.

The image from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter shows a crater about 100 feet (30 meters) in diameter at the center of a radial burst painting the surface with a pattern of bright and dark tones. It is available online

The scar appeared at some time between imaging of this location by the orbiter's Context Camera in July 2010 and again in May 2012. Based on apparent changes between those before-and-after images at lower resolution, researchers used HiRISE to acquire this new image on Nov. 19, 2013. The impact that excavated this crater threw some material as far as 9.3 miles (15 kilometers).

The Mars Reconnaissance Orbiter Project is managed by NASA's Jet Propulsion Laboratory, Pasadena, Calif., for NASA's Science Mission Directorate, Washington. JPL is a division of the California Institute of Technology in Pasadena. HiRISE is operated by the University of Arizona, Tucson. The instrument was built by Ball Aerospace & Technologies Corp., Boulder, Colo. Malin Space Science Systems, San Diego, built and operates the Context Camera
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A team of Harvard scientists and engineers has demonstrated a new type of battery that could fundamentally transform the way electricity is stored on the grid, making power from renewable energy sources such as wind and solar far more economical and reliable.

The novel battery technology is reported in a paper published in Nature on January 9. Under the OPEN 2012 program, the Harvard team received funding from the U.S. Department of Energy's Advanced Research Projects Agency-Energy (ARPA-E) to develop the innovative grid-scale battery and plans to work with ARPA-E to catalyze further technological and market breakthroughs over the next several years.


The paper reports a metal-free flow battery that relies on the electrochemistry of naturally abundant, inexpensive, small organic (carbon-based) molecules called quinones, which are similar to molecules that store energy in plants and animals.

The mismatch between the availability of intermittent wind or sunshine and the variability of demand is the biggest obstacle to getting a large fraction of our electricity from renewable sources. A cost-effective means of storing large amounts of electrical energy could solve this problem.

The battery was designed, built, and tested in the laboratory of Michael J. Aziz, Gene and Tracy Sykes Professor of Materials and Energy Technologies at the Harvard School of Engineering and Applied Sciences (SEAS). Roy G. Gordon, Thomas Dudley Cabot Professor of Chemistry and Professor of Materials Science, led the work on the synthesis and chemical screening of molecules. Alán Aspuru-Guzik, Professor of Chemistry and Chemical Biology, used his pioneering high-throughput molecular screening methods to calculate the properties of more than 10,000 quinone molecules in search of the best candidates for the battery.

Flow batteries store energy in chemical fluids contained in external tanks -- as with fuel cells -- instead of within the battery container itself. The two main components -- the electrochemical conversion hardware through which the fluids are flowed (which sets the peak power capacity), and the chemical storage tanks (which set the energy capacity) -- may be independently sized. Thus the amount of energy that can be stored is limited only by the size of the tanks. The design permits larger amounts of energy to be stored at lower cost than with traditional batteries.

By contrast, in solid-electrode batteries, such as those commonly found in cars and mobile devices, the power conversion hardware and energy capacity are packaged together in one unit and cannot be decoupled. Consequently they can maintain peak discharge power for less than an hour before being drained, and are therefore ill suited to store intermittent renewables.

"Our studies indicate that one to two days' worth of storage is required for making solar and wind dispatchable through the electrical grid," said Aziz.

To store 50 hours of energy from a 1-megawatt power capacity wind turbine (50 megawatt-hours), for example, a possible solution would be to buy traditional batteries with 50 megawatt-hours of energy storage, but they'd come with 50 megawatts of power capacity. Paying for 50 megawatts of power capacity when only 1 megawatt is necessary makes little economic sense.

For this reason, a growing number of engineers have focused their attention on flow battery technology. But until now, flow batteries have relied on chemicals that are expensive or difficult to maintain, driving up the energy storage costs.

The active components of electrolytes in most flow batteries have been metals. Vanadium is used in the most commercially advanced flow battery technology now in development, but its cost sets a rather high floor on the cost per kilowatt-hour at any scale. Other flow batteries contain precious metal electrocatalysts such as the platinum used in fuel cells.

The new flow battery developed by the Harvard team already performs as well as vanadium flow batteries, with chemicals that are significantly less expensive, and with no precious metal electrocatalyst.

"The whole world of electricity storage has been using metal ions in various charge states but there is a limited number that you can put into solution and use to store energy, and none of them can economically store massive amounts of renewable energy," Gordon said. "With organic molecules, we introduce a vast new set of possibilities. Some of them will be terrible and some will be really good. With these quinones we have the first ones that look really good."

Aspuru-Guzik noted that the project is very well aligned with the White House Materials Genome Initiative. "This project illustrates what the synergy of high-throughput quantum chemistry and experimental insight can do," he said. "In a very quick time period, our team honed in to the right molecule. Computational screening, together with experimentation, can lead to discovery of new materials in many application domains."

Quinones are abundant in crude oil as well as in green plants. The molecule that the Harvard team used in its first quinone-based flow battery is almost identical to one found in rhubarb. The quinones are dissolved in water, which prevents them from catching fire.

To back up a commercial wind turbine, a large storage tank would be needed, possibly located in a below-grade basement, said co-lead author Michael Marshak, a postdoctoral fellow at SEAS and in the Department of Chemistry and Chemical Biology. Or if you had a whole field of turbines or large solar farm, you could imagine a few very large storage tanks.

The same technology could also have applications at the consumer level, Marshak said. "Imagine a device the size of a home heating oil tank sitting in your basement. It would store a day's worth of sunshine from the solar panels on the roof of your house, potentially providing enough to power your household from late afternoon, through the night, into the next morning, without burning any fossil fuels."

"The Harvard team's results published in Nature demonstrate an early, yet important technical achievement that could be critical in furthering the development of grid-scale batteries," said ARPA-E Program Director John Lemmon. "The project team's result is an excellent example of how a small amount of catalytic funding from ARPA-E can help build the foundation to hopefully turn scientific discoveries into low-cost, early-stage energy technologies."

Team leader Aziz said the next steps in the project will be to further test and optimize the system that has been demonstrated on the bench top and bring it toward a commercial scale. "So far, we've seen no sign of degradation after more than 100 cycles, but commercial applications require thousands of cycles," he said. He also expects to achieve significant improvements in the underlying chemistry of the battery system. "I think the chemistry we have right now might be the best that's out there for stationary storage and quite possibly cheap enough to make it in the marketplace," he said. "But we have ideas that could lead to huge improvements."

By the end of the three-year development period, Connecticut-based Sustainable Innovations, LLC, a collaborator on the project, expects to deploy demonstration versions of the organic flow battery contained in a unit the size of a horse trailer. The portable, scaled-up storage system could be hooked up to solar panels on the roof of a commercial building, and electricity from the solar panels could either directly supply the needs of the building or go into storage and come out of storage when there's a need. Sustainable Innovations anticipates playing a key role in the product's commercialization by leveraging its ultra-low cost electrochemical cell design and system architecture already under development for energy storage applications.

"You could theoretically put this on any node on the grid," Aziz said. "If the market price fluctuates enough, you could put a storage device there and buy electricity to store it when the price is low and then sell it back when the price is high. In addition, you might be able to avoid the permitting and gas supply problems of having to build a gas-fired power plant just to meet the occasional needs of a growing peak demand."This technology could also provide very useful backup for off-grid rooftop solar panels -- an important advantage considering some 20 percent of the world's population does not have access to a power distribution network.

William Hogan, Raymond Plank Professor of Global Energy Policy at Harvard Kennedy School, and one of the world's foremost experts on electricity markets, is helping the team explore the economic drivers for the technology.Trent M. Molter, President and CEO of Sustainable Innovations, LLC, provides expertise on implementing the Harvard team's technology into commercial electrochemical systems.

"The intermittent renewables storage problem is the biggest barrier to getting most of our power from the sun and the wind," Aziz said. "A safe and economical flow battery could play a huge role in our transition off fossil fuels to renewable electricity. I'm excited that we have a good shot at it."

In addition to Aziz, Marshak, Aspuru-Guzik, and Gordon, the co-lead author of the Nature paper was Brian Huskinson, a graduate student with Aziz; coauthors included research associate Changwon Suh and postdoctoral researcher Süleyman Er in Aspuru-Guzik's group; Michael Gerhardt, a graduate student with Aziz; Cooper Galvin, a Pomona College undergraduate; and Xudong Chen, a postdoctoral fellow in Gordon's group.

This work was supported in part by the U.S. Department of Energy's Advanced Research Project Agency-Energy (ARPA-E), the Harvard School of Engineering and Applied Sciences, the National Science Foundation (NSF) Extreme Science and Engineering Discovery Environment (OCI-1053575), an NSF Graduate Research Fellowship, and the Fellowships for Young Energy Scientists program of the Foundation for Fundamental Research on Matter, which is part of the Netherlands Organization for Scientific Research (NWO).

Researchers found that the most common emotions trigger strong bodily sensations, and the bodily maps of these sensations were topographically different for different emotions. The sensation patterns were, however, consistent across different West European and East Asian cultures, highlighting that emotions and their corresponding bodily sensation patterns have a biological basis.

"Emotions adjust not only our mental, but also our bodily states. This way the prepare us to react swiftly to the dangers, but also to the opportunities such as pleasurable social interactions present in the environment. Awareness of the corresponding bodily changes may subsequently trigger the conscious emotional sensations, such as the feeling of happiness," tells assistant professor Lauri Nummenmaa from Aalto University.

"The findings have major implications for our understanding of the functions of emotions and their bodily basis. On the other hand, the results help us to understand different emotional disorders and provide novel tools for their diagnosis."

The research was carried out on line, and over 700 individuals from Finland, Sweden and Taiwan took part in the study. The researchers induced different emotional states in their Finnish and Taiwanese participants. Subsequently the participants were shown with pictures of human bodies on a computer, and asked to colour the bodily regions whose activity they felt increasing or decreasing.

The research was funded by European Research Council (ERC), The Academy of Finland and the Aalto University (aivoAALTO project)

The results were published on 31 December, 2013 in the scientific journal Proceedings of The National Academy of Sciences
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GSAT-14 is an Indian communications satellite which was succesfully launched in 5 January 2014. It is expected to replace the GSAT-3 satellite, which was launched in 2004. GSAT-14 will be launched by a Geosynchronous Satellite Launch Vehicle Mk.II, incorporating an Indian-built cryogenic engine on the third stage.
It will be an acid test for India as it seeks to prove the design, realisation and sustained firing of its indigenously built cryogenic engine. There is pressure on the Indian Space Research Organisation (ISRO) to produce a winner because of two back-to-back failures of the GSLV flights in 2010 - the first, with an indigenous cryogenic engine, on April 15 and the next, with a Russian cryogenic engine, on December 25.

The 29-hour countdown for the launch of India's heavy rocket geosynchronous satellite launch vehicle-development 5 (GSLV-D5) with the indigenous engine had started on Saturday 11.18 a.m. at Sriharikota in Andhra Pradesh.

The Rs.356 crore launch mission has twin purpose - to flight test the cryogenic engine designed and built by Indian Space Research Organisation (ISRO), and to put in orbit communication satellite GSAT-14.

 The launch is scheduled for 4.18 p.m. Sunday. The rocket port is located about 80 km from Chennai.A cryogenic engine is more efficient as it provides more thrust for every kilogram of propellant burnt.ISRO was to launch this rocket last August but aborted it just hours before the deadline as the fuel started leaking from its second stage or engine.According to the ISRO official, the second stage was replaced with a new one built with a different metal.

"We also replaced some critical components in the four strap-on motors of the first stage as a matter of precaution," said the official.The successful flight of this rocket is crucial for India as it will be the first step towards building rockets that can carry heavier payloads, up to four tonnes.

GSLV-D5 at the Second Launch Pad (Umbilical Tower) in Sriharikota. (Photo courtesy ISRO)

For ISRO perfecting the cryogenic engine technology is crucial as it can save precious foreign exchange by launching communication satellites by itself than depending on foreign rockets.

This will be the first mission of GSLV in the last four years, after two such rockets failed in 2010. One of the GSLV rockets flew with an Indian cryogenic engine, and the other one with a Russian engine.

The GSLV is a three stage/engine rocket. The first stage is fired with solid fuel, the second with liquid fuel and the third is the cryogenic engine.

The successful flight of this rocket is crucial for India as it will be the first step towards building rockets that can carry heavier payloads of up to four tonnes.

ISRO is planning to launch an upgraded version of GSLV Mark III rocket soon with a dummy payload.

The design payload capacity of GSLV Mark III is four tonnes. However, the rocket will not have the cryogenic engine which is under development. The mission is mainly to test the rocket's other systems and its aerodynamic stability.


SOURCE: INDIA TODAY

Mankind always has, and always will, fight wars. And in order to fight said wars, man needed weapons. Using whatever skills and resources they had, man built tools that would slash, smash, pierce and tear their enemies. Every nation had weapons that made their armies unique. Today when we talk about ancient weapons we immediately think swords, spears, bows and axes. But I find interest in weapons that strike me as out of the norm. This list is an assortment of weapons that have designs, backgrounds or usages that I find rather out of the ordinary. If you feel like anything is excluded or missing from the list, remember there exists a comment section for you to do with as you will!

# 10 Mere Club

Used by the Māori tribes of New Zealand, this simple-looking, yet solid, club was built from nephrite jade. Strangely enough, the Māori used the 12-20 inch club for jabbing and thrusting instead of swinging downward blows in the way that most other clubs are used. To the Māori, the mere was a very spiritual weapon. They named their mere clubs and passed them down through generations. They even believed that the clubs contained a mana (spiritual force) of their own. The Māori revered their mere clubs greatly. They were a symbol of leadership, and if any mere that was considered important by a tribe was misplaced, great efforts were taken by the tribe to make sure the mere was located and returned to its respective owner.

# 9 Hook Swords

Perhaps the most well-known on this list, the Chinese hook swords were wielded by the normally passive Shoalin monks of northern China. Beautifully and artistically designed, the blades were curved into a hook shape at the end which allowed the user to connect the blades by the tip and wield them as a single, long-ranged weapon. The crescent shaped guards were excellent at blocking blows as well as slashing enemies who got too close. The ends of the hilts were sharpened into daggers for stabbing at close range. These swords measured from 4-6 feet from the top of the hook to the end of the sharpened hilt. The blades saw most of their usage from civilians, as the Chinese military did not use them in any of their armies.

# 8 Kpinga

The kpinga was a throwing knife that was used by experienced warriors of the Azande tribe. The Zande people were residents of Nubia, a region in Africa composed of northern Sudan and southern Egypt. The knife (also known by its nickname, the Hunga Munga) was up to 22 inches long and had three blades that extended from the center. The blade closest to the handle is in the shape of a man’s genitals, and represented the masculine power of its owner. The alignment of the blades on the kpinga drastically increased the chances of impaling a target on contact. When the owner of the weapon was married, he presented the kpinga as a gift to the family of his wife.

# 7 Macuahuitl

The macuahuitl was basically a large, sword-shaped piece of wood, with razor-sharp pieces of obsidian embedded in the sides. Since the macuahuitl lacked a sharp point, it couldn’t be used as a stabbing weapon; however the jagged rows of obsidian gave the weapon a vicious tearing power that could cut deep lacerations in the enemy. The wood itself is heavy and strong enough to clobber opponents, thus enabling the Aztec to capture the foe alive to be used in their famous ritual sacrifices. There have been accounts of maquahuitls being able to decapitate horses, which is impressive, for a horse’s head is a good deal thicker than that of an adult human being.

# 6 Scissor

This rather odd-looking weapon was used in the arenas by the gladiators of the ancient Roman Empire. Interestingly enough, the gladiators who wielded the scissor in combat were also known as scissors. The metal casing at the bottom formed a long tube that covered the gladiator’s arm, allowing the weapon to easily block and parry, as well as counterattack. Made from hardened steel, the scissor measured up to one and a half feet long. It is surprisingly light, weighing in at an easy 5-7 pounds; this allowed the scissor to be wielded with a good amount of speed. The scissor’s unique shape and design made it a crowd favorite.

# 5 Chakram

Don’t be fooled, the chakram is not something you would want to play frisbee with. Unlike the frisbee, the chakram was often thrown vertically rather than horizontally. The deadly circle of metal was up to a foot in diameter. It’s extremely sharp edge ensured that the chakram could slice off arms and legs with ease. This weapon originated from India, where it was used extensively by the high ranking Indian Sikhs. Much like a distant relative, the shrunken, the chakram could be stacked one on the other and thrown repeatedly. One interesting throwing method used by professional warriors was to spin the chakram on their index finger, and then, with a sharp flick of the wrist, launch the whirring blade at their opponent.

# 4 Chu Ko Nu

Another Chinese weapon, the chu ko nu was basically an ancestor to the automatic rifle – it sacrificed range and power for a quick reload time. The wooden case on the top of the crossbow held 10 crossbow bolts which fell into place when the rectangular lever on the back was pulled back after firing a bolt. One interesting fact is that the chu ko nu last saw its use in the Sino-Japanese wars of 1894-1895, years after the rise of firearms. The crossbow could fire on average a total of 10 bolts within 15 seconds. Which, when compared to the reload speed of normal bows and crossbows, is a great improvement. For added effectiveness, some of the bolts were tipped with poison from the deadly aconite flower, also known as wolfsbane.

# 3 Nest of Bees

Now I have to hand it to the Chinese, their weapons have made four entries on my list. Third place is taken by the nest of bees, or flying fire. Basically it was a wooden container filled with tubes in the shape of a hexagon, which, when viewed from the front, gave the weapon the appearance of a large honeycomb. Inside each of the tubes was a rocket propelled arrow. The rockets launched the arrows with more power and range than that of a traditional bow. Up to 32 arrows could be launched from a nest at once. The Chinese would fire thousands of bees’ nests at once, killing plenty of enemies within seconds.

# 2 Katar

This Indian weapon gave its owner the claws of wolverine, minus the strength and cutting power of adamantium. The katar at first glance has a single blade, however when a trigger on the h-shaped handle was activated, the blade would split into three, one on the middle and one on each side. The three blades not only made the weapon more effective at stabbing and slashing, but they also intimidated and/or startled the opponent. The blade’s positioning on the handle also allowed it to easily block attacks. Its unusual design has yet another purpose – the triple blades could easily stab through all kinds of Asian armor with ease.

# 1 Zhua

One look at this incredibly odd-looking device was more than enough to convince me that it deserved the number one place on this list. Yet another Chinese weapon, the zhua’s conspicuous iron “hand” at the end had sharp claw-like nails that would impale flesh, and then tear it off from the body. The sheer weight of the zhua was enough to kill the opponent, but the claws made it even deadlier. When wielded by a professional, it could be used to pull mounted soldiers off their horse. But the main use of the zhua was to pull off the shields of enemies, leaving them exposed to the clawed hand of iron.

Courtesy : ISRO

Fossils are often stored in plaster casts, or jackets, to protect them from damage. Getting information about a fossil typically requires the removal of the plaster and all the sediment surrounding it, which can lead to loss of material or even destruction of the fossil itself.German researchers studied the feasibility of using CT and 3-D printers to nondestructively separate fossilized bone from its surrounding sediment matrix and produce a 3-D print of the fossilized bone itself.

\"The most important benefit of this method is that it is non-destructive, and the risk of harming the fossil is minimal," said study author Ahi Sema Issever, M.D., from the Department of Radiology at Charité Campus Mitte in Berlin. "Also, it is not as time-consuming as conventional preparation."

Dr. Issever and colleagues applied the method to an unidentified fossil from the Museum für Naturkunde, a major natural history museum in Berlin. The fossil and others like it were buried under rubble in the basement of the museum after a World War II bombing raid. Since then, museum staff members have had difficulty sorting and identifying some of the plaster jackets.Researchers performed CT on the unidentified fossil with a 320-slice multi-detector system. The different attenuation, or absorption of radiation, through the bone compared with the surrounding matrix enabled clear depiction of a fossilized vertebral body.

After studying the CT scan and comparing it to old excavation drawings, the researchers were able to trace the fossil's origin to the Halberstadt excavation, a major dig from 1910 to 1927 in a clay pit south of Halberstadt, Germany. In addition, the CT study provided valuable information about the condition and integrity of the fossil, showing multiple fractures and destruction of the front rim of the vertebral body.Furthermore, the CT dataset helped the researchers build an accurate reconstruction of the fossil with selective laser sintering, a technology that uses a high-powered laser to fuse together materials to make a 3-D object.

Dr. Issever noted that the findings come at a time when advances in technology and cheaper availability of 3-D printers are making them more common as a tool for research. Digital models of the objects can be transferred rapidly among researchers, and endless numbers of exact copies may be produced and distributed, greatly advancing scientific exchange, Dr. Issever said. The technology also potentially enables a global interchange of unique fossils with museums, schools and other settings.

"The digital dataset and, ultimately, reproductions of the 3-D print may easily be shared, and other research facilities could thus gain valuable informational access to rare fossils, which otherwise would have been restricted," Dr. Issever said. "Just like Gutenberg's printing press opened the world of books to the public, digital datasets and 3-D prints of fossils may now be distributed more broadly, while protecting the original intact fossil."

ndia launched its first mission to Mars this afternoon from the Sriharikota spaceport in Andhra Pradesh, beginning a 300-day journey to study the Martian atmosphere.

Mangalyaan, which means "Mars craft" in Hindi, is the size of a small car and is scheduled to begin orbiting Mars by September, searching for methane and signs of minerals.

The satellite is golden in colour and is being carried by a rocket much smaller than American or Russian equivalents.

Lacking the power to fly directly, the 350-tonne launch vehicle will orbit Earth for nearly a month, building up the necessary velocity to break free from our planet's gravitational pull.

Only then will it begin the second stage of its nine-month journey which will test India's scientists to the full, five years after they sent a probe called Chandrayaan to the moon.

The total cost of the project is 450 crores, one sixth of the cost of a Mars probe set to be launched by NASA in 13 days.

Only the United States, Europe, and Russia have sent probes that have orbited or landed on Mars. Probes to Mars have a high failure rate. A similar mission by China failed to leave Earth's orbit in 2011.

"This is a technology demonstration project, a mission that will announce to the world India has the capability to reach as far away as Mars, "said K. Radhakrishnan, chairman of the Indian Space and Research Organization

Source: ndtv.com