| Germanium (110) |  |
| Thorium (25) | |
| Uranium (60) | |
The Stuxnet virus, designed to destroy Iran's uranium-enriching gas centrifuges, and first identified that same year, is believed to have been a demonstration of the US's abilities to wage war by attacking enemy computer systems.
By increasing the strength of the pili nanowires she improved their ability to clean up uranium and other toxic wastes.
and increases their ability to neutralize even more uranium. The improvement also allows the bacteria to survive longer even when exposed to higher concentrations of the radioactive material.
Geobacter immobilizing uranium can be described as nature s version of electroplating. The beefed-up microbes engulf the uranium
and turn it into a mineral which prevents the toxic material from leaching into groundwater.
Reguera s team had linked previously the conductive pili to the ability of the microbe to mineralize the soluble uranium.
As the biofilm concentrates many nanowires around the Geobacter cells more uranium can be mineralized bound
and boosts the Geobacter s pili armor so the biofilm now can pull double duty by helping mineralize uranium.
The shield keeps the uranium from penetrating deep into the Geobacter biofilm. By keeping this process on the surface of the film the bacteria are exposed not to uranium
and as a community they are able to clean up more toxic waste. he results surpassed our most optimistic predictionsreguera says. ven thin biofilms immobilized uranium like sponges.
They reduced it to a mineral all while not suffering any damage to themselves for prolonged periods of time. ven
when exposed to extremely high and toxic concentrations of uranium levels that would destroy individual Geobacter cells the biofilms didn t just survive they thrived she adds.
#China and India race to fully harness thorium for nuclear power Thorium is an alternative to uranium as a way of doing nuclear fission.
Although the chemical element thorium sounds like the kind of material used as a plot device in a comic book blockbuster,
Thorium is being hailed as the key in the bid to find safer and more sustainable sources of nuclear energy to provide our electricity.
thorium has taken almost 200 years to be taken seriously as an energy contender. After a period in the 1950s and 1960s in which it flirted with thorium,
the US government shut down its research into the radioactive element, preferring to go the uranium route.
Critics say thorium was pushed aside because uranium was an easier component for nuclear weapons. But times have changed,
and thorium s status as a safer alternative to uranium is now a help, not the hindrance it was during the Cold war.
India, which has hundreds of thousands of tonnes of the metal amid its terrain has announced plans to build a thorium-based nuclear reactor by 2016.
But it faces competition from China, where the schedule to deliver a thorium-based nuclear power plant was overhauled recently,
meaning scientists in Shanghai have been told to deliver such a facility within the next ten years. While thorium nuclear exploration is had not New britain its own reactor in Dorset carrying out tests 40 years ago the will to make it a viable energy source is growing stronger.
Professor Roger Barlow from the University of Huddersfield is part of a team researching thorium power generation.
Thorium is an alternative to uranium as a way of doing nuclear fission he told Metro.
He said thorium is safer because an overheating thorium reactor can be switched simply off, avoiding the problem that occurred at Fukushima, for instance.
Thorium also produces less radioactive waste than uranium, waste which needs to be secured for hundreds rather than tens of thousands of years.
He added that it is extremely difficult to weaponise. Thorium is not fissile, meaning it cannot be split to release energy alone,
but when exposed to neutrons it will react to produce a particular isotope of uranium (U-233) that becomes the nuclear fuel.
Proponents say this is less dangerous and produces less waste than the usual uranium power plant reaction that generates plutonium,
which can be used to make weapons. But who will be the first across the line in the thorium race?
The Chinese have thrown a lot of resources at it, said Prof Barlow. I don t know if they ll succeed or not.
Thorium is not without its critics, who point to its nuclear reaction producing U-232, the decay products
and Padmanabha Krishnagopala Iyengar, former DAE secretary, claim that Indian nuclear scientists are giving up prematurely on their thorium research programme in exchange for a few uranium reactors from abroad.
India has very little domestic uranium but one-quarter of the world's thorium reserves;
its thorium research programme focuses on turning the material into fissile uranium-233 for use as reactor fuel.
Fast breeder reactors, of the type under construction in Kalpakkam, would breed uranium-233 in thorium blankets surrounding a plutonium core.
Recovering plutonium and uranium-233 from spent fuel is key to India's thorium programme,
Still, at least one overseas company is betting on thorium. Last month, Thorium power in Mclean, Virginia, with a market capitalization of about $40 million
This behavior is similar to that of traditional semiconductors such as silicon and germanium. But if the graphene starts out with high electron concentration the pulse decreases its conductivity the same way that a metal usually behaves.
During it#3-month exploration it will search for natural resources and rare elements such as titanium and uranium.
That materialbbreviated GSTONSISTS of a thin layer of an alloy of germanium, antimony, and tellurium.
Germanium lasers, demonstrated by Kimerling group in 2010, offer a prime example. ne of the big issues today is the light source,
Our germanium laser would be a way to do that. It's at the research rather than the commercial stage at this point,
growing germanium crystals on amorphous substances at temperatures low enough for fabricating electronics as well. Such approaches, focused on the long term, will achieve monolithic integration for chips with an electronic front end with optics embedded in the back end
which are compounds of lithium, germanium, phosphorus, and sulfur, but the principles derived from this research could lead to even more effective materials,
The new TFET is made from two atomically-thin layers of semiconducting molybdenum sulfide crystal on top of a substrate of germanium.
and germanium. ad we used an unknown sample for the demonstration, we would not have been in the position to correctly interpret the functionality of our approach, Kehr stresses.
Phase-change memory involves an alloy of germanium antimony and tellurium. Applying a small jolt of electricity to the alloy results in a change in its structure.
Ladee readings also revealed an unexpected source of some of the helium in the lunar exosphere. bout 20 percent of the helium is coming from the moon itself, most likely as the result from the decay of radioactive thorium and uranium
Germanium is a semiconductor and this method provides a straightforward way to make semiconducting nanoscale circuits from graphene, a form of carbon only one atom thick.
"UW researchers used chemical vapor deposition to grow graphene nanoribbons on germanium crystals. This technique flows a mixture of methane, hydrogen and argon gases into a tube furnace.
At high temperatures, methane decomposes into carbon atoms that settle onto the germanium's surface to form a uniform graphene sheet.
when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges,"said Michael Arnold, an associate professor of materials science and engineering at UW-Madison."
researchers confirmed the presence of graphene nanoribbons growing on the germanium. Data gathered from the electron signatures allowed the researchers to create images of the material's dimensions and orientation.
"What's even more interesting is that these nanoribbons can be made to grow in certain directions on one side of the germanium crystal,
"For use in electronic devices, the semiconductor industry is interested primarily in three faces of a germanium crystal.
0). Previous research shows that graphene sheets can grow on germanium crystal faces (1, 1, 1) and (1, 1,
if there is any unique interaction between the germanium and graphene that may play a role e
And, given that the basic operating principles of hot-carrier graphene devices are substantially different from traditional silicon or germanium semiconductors,
The team constructed a unique cell that clamps a multiferroic barium cobalt germanium oxide (Ba2coge2o7) crystal between a pair of zirconium oxide pistons (Fig. 1). They then investigated how the sample electric polarization changed under uniaxial stress.
Now, University of Wisconsin-Madison engineers have discovered a way to grow graphene nanoribbons with desirable semiconducting properties directly on a conventional germanium semiconductor wafer.
and is compatible with the prevailing infrastructure used in semiconductor processing. raphene nanoribbons that can be grown directly on the surface of a semiconductor like germanium are more compatible with planar processing that used in the semiconductor industry,
straight edges directly on germanium wafers using a process called chemical vapor deposition. In this process, the researchers start with methane,
which adsorbs to the germanium surface and decomposes to form various hydrocarbons. These hydrocarbons react with each other on the surface,
the graphene crystals naturally grow into long nanoribbons on a specific crystal facet of germanium. By simply controlling the growth rate and growth time,
when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges,
or growing, at seemingly random spots on the germanium and are oriented in two different directions on the surface.
Progressively zoomed-in images of graphene nanoribbons grown on germanium. The ribbons automatically align perpendicularly and naturally grow with their edges oriented along the carbon-carbon bond direction, known as the armchair edge configuration a
Germanium is a semiconductor, and this method provides a straightforward way to make semiconducting nanoscale circuits from graphene, a form of carbon only one atom thick.
"UW researchers used chemical vapor deposition to grow graphene nanoribbons on germanium crystals. This technique flows a mixture of methane, hydrogen,
At high temperatures, methane decomposes into carbon atoms that settle onto the germanium's surface to form a uniform graphene sheet.
when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges,"said Michael Arnold, an associate professor of materials science and engineering at UW-Madison."
researchers confirmed the presence of graphene nanoribbons growing on the germanium. Data gathered from the electron signatures allowed the researchers to create images of the material's dimensions and orientation.
"What's even more interesting is that these nanoribbons can be made to grow in certain directions on one side of the germanium crystal,
"For use in electronic devices, the semiconductor industry is interested primarily in three faces of a germanium crystal.
0). Previous research shows that graphene sheets can grow on germanium crystal faces (1, 1, 1) and (1, 1,
if there is any unique interaction between the germanium and graphene that may play a role e
a semiconducting layer made of silicon and germanium.""had used we an unknown sample for the demonstration,
Now, University of Wisconsin-Madison engineers have discovered a way to grow graphene nanoribbons with desirable semiconducting properties directly on a conventional germanium semiconductor wafer.
"Graphene nanoribbons that can be grown directly on the surface of a semiconductor like germanium are more compatible with planar processing that's used in the semiconductor industry,
straight edges directly on germanium wafers using a process called chemical vapor deposition. In this process, the researchers start with methane,
which adsorbs to the germanium surface and decomposes to form various hydrocarbons. These hydrocarbons react with each other on the surface,
the graphene crystals naturally grow into long nanoribbons on a specific crystal facet of germanium. By simply controlling the growth rate and growth time,
when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges,
or growing, at seemingly random spots on the germanium and are oriented in two different directions on the surface.
The researchers used their model to study the thermal resistance of a nanowire containing an equal mix of silicon and germanium atoms.
and the U s. Department of energy's Argonne National Laboratory has confirmed a new way to control the growth paths of graphene nanoribbons on the surface of a germainum crystal (Nature Communications,"Direct oriented growth of armchair graphene nanoribbons on germanium").
"Germanium is a semiconductor and this method provides a straightforward way to make semiconducting nanoscale circuits from graphene, a form of carbon only one atom thick.
"UW researchers used chemical vapor deposition to grow graphene nanoribbons on germanium crystals. This technique flows a mixture of methane, hydrogen and argon gases into a tube furnace.
At high temperatures, methane decomposes into carbon atoms that settle onto the germanium's surface to form a uniform graphene sheet.
when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges,"said Michael Arnold, an associate professor of materials science and engineering at UW-Madison."
researchers confirmed the presence of graphene nanoribbons growing on the germanium. Data gathered from the electron signatures allowed the researchers to create images of the material's dimensions and orientation.
"What's even more interesting is that these nanoribbons can be made to grow in certain directions on one side of the germanium crystal,
"For use in electronic devices, the semiconductor industry is interested primarily in three faces of a germanium crystal.
0). Previous research shows that graphene sheets can grow on germanium crystal faces (1, 1, 1) and (1, 1,
if there is any unique interaction between the germanium and graphene that may play a role e
They built an accordion-like structure from germanium leaving a 2. 7-centimetre-wide cavity in the middle for the toy mouse.
The germanium sent infrared rays from behind the mouse on a curved path around the cavity, then bent them back into straight lines for the camera,
Germanium is a semiconductor, and this method provides a straightforward way to make semiconducting nanoscale circuits from graphene, a form of carbon only one atom thick.
"UW researchers used chemical vapor deposition to grow graphene nanoribbons on germanium crystals. This technique flows a mixture of methane, hydrogen,
At high temperatures, methane decomposes into carbon atoms that settle onto the germanium's surface to form a uniform graphene sheet.
when graphene grows on germanium, it naturally forms nanoribbons with these very smooth, armchair edges,"said Michael Arnold, an associate professor of materials science and engineering at UW-Madison."
researchers confirmed the presence of graphene nanoribbons growing on the germanium. Data gathered from the electron signatures allowed the researchers to create images of the material's dimensions and orientation.
"What's even more interesting is that these nanoribbons can be made to grow in certain directions on one side of the germanium crystal,
"For use in electronic devices, the semiconductor industry is interested primarily in three faces of a germanium crystal.
0). Previous research shows that graphene sheets can grow on germanium crystal faces (1, 1, 1) and (1, 1,
if there is any unique interaction between the germanium and graphene that may play a role.
The newly discovered, exotic nuclei are one isotope each of heavy elements berkelium, neptunium and uranium and two isotopes of the element americium.
Shaughnessy said. hen you realize that naturally occurring uranium has 146 neutrons and this new isotope only has 124 neutrons,
neptunium, uranium and americium discovered were created as the end products of such collisions. They are unstable
"It stores data using the same material that found in rewritable CDS and DVDS-a phase-change alloy of germanium-antimony-tellurium known as GST."
Conventional semiconductor detectors such as germanium and silicon require low temperatures to operate which limits their applications outside of laboratories.
For example, germanium detectors must be cooled to liquid nitrogen temperature (about 77 Kelvin or-196 degrees Celsius) to produce spectroscopic data.
#Skimming uranium from the sea Researchers developed a protein-based, genetically encodable system that can bind water-soluble uranium with exceedingly high affinity and selectivity.
This is the first known demonstration of a bacterial system used to mine ocean-based uranium that reduces the expense
The overall method developed could find broad applications in sequestration and bioremediation of water-soluble uranium and similar transuranic elements.
Uranium plays an important role in the search for alternative energies to fossil fuels; however, uranium resources on land are limited.
The oceans are estimated to contain 1, 000 times as much uranium as is buried in deposits on land,
but unfortunately, the uranium in the ocean is in the form of water-soluble uranyl (UO22)
+which is present at a very low concentration (13.7 nm). The uranyl is bound by carbonate and other anions,
making separating the uranium extremely complex. After years of trying to find an efficient and affordable way to extract uranyl, researchers at the University of Chicago, Peking University,
However, they grow in random spots on germanium wafer in two different directions, which scientists have to control
properties directly on a conventional germanium semiconductor wafer. This discovery is aimed at allowing manufacturers of electronics to develop the next-generation of electronic devices that will have much greater performance.
Professor Michael Arnold, one of the authors of the study, said raphene nanoribbons that can be grown directly on the surface of a semiconductor like germanium are more compatible with planar processing that used in the semiconductor industry,
straight edges directly on germanium wafers. As scientists describe it, they are growing graphene in this shape via process called chemical vapour deposition.
which adsorbs to the germanium surface and decomposes to form various hydrocarbons. Then these hydrocarbons react with each other
and form graphene on surface of the germanium wafer. Team of researchers made this discovery
Scientists found that at a very slow growth rate graphene naturally grows into long nanoribbons on a specific crystal facet of germanium
graphene grows at completely random spots on the germanium wafer. Furthermore, strips are oriented in two different directions on the surface.
including molten salt reactors, thorium, fast neutron reactors, pebble bed reactors and fusion. Some of these could be potentially safer and more effective than conventional designs e
IBM researchers are trying to prop up Moore law using silicon-germanium transistor channels in effort to create a 7-nanometer chip within the next four years.
including silicon germanium. Embedding motion sensors in clothing, mcube long-term goal, would require better ways of powering the devices
But some devices are starting to use fast silicon-germanium radio chips operating at millimeter (mm) wavelengths above 10 GHZ.
In order to achieve this, the team used a number of nonconventional semiconductor manufacturing methods including the development of transistor channels made of silicon-germanium, or Sige
When some germanium is added to the mix, electron mobility is increased. These transistors are each only 7 nanometers wide that's about 1/10, 000th the width of a human hair and three times the width of a single strand of DNA.
and was able to develop silicon-germanium transistors to boost processing power. 2015 AF o
and Pakistan has started reportedly operating a third plutonium reactor, Squassoni said. She said the United states has good rhetoric on nuclear nonproliferation,
material, germanium telluride (Gete), when it is hit by a femtosecond laser pulse. In UEC, a sample of crystalline Gete is bombarded with a femtosecond laser pulse,
and gather data about reactions that can be observed only as they are happening inside a battery("Probing Lithium Germanide Phase Evolution and Structural Change in a Germanium-in-Carbon nanotube Energy storage system").
Germanium can take on more lithium during the reaction than other materials-making it a promising component for delivering higher battery capacity and superior discharge speeds,
Germanium is less abundant and more costly than other materials, such as silicon or carbon, but high battery performance resulting from its favorable uptake of lithium may be a factor in making lithium-germanide batteries attractive in the marketplace.
When the companion element-in this case germanium-takes up lithium, the volume of the electrode expands dramatically.
the scientists found a way to protect the germanium from expanding and becoming ineffective after it takes on lithium.
The secret proved to be forming the germanium into tiny"wires "and encasing them in small,
Without embedding germanium in carbon tubes, a battery performs well for a few charging-discharging cycles,
with silicon germanium technology to create CMOS chips. It is fully compatible with current high volume chip fabrication technology,
germanium telluride (Gete), when it is hit by a femtosecond laser pulse. In UEC, a sample of crystalline Gete is bombarded with a femtosecond laser pulse,
including silicon and germanium. In addition to being able to tune the distance between the lobes on nanowires,
The material comprised of germanium, antimony and tellurium in which data media store information may also be suitable as an extremely fast light switch for optical communication or data processing.
Electrons are diffracted differently in the crystalline structure of a compound of germanium, antimony and tellurium (GST) than in the amorphous one.
have formed successfully a heterojunction solar cell using germanium QDS on an ordinary n-type silicon wafer. Individual germanium quantum dots were coated with silicon dioxide (silica),
doped to make them p-type, and then deposited, using Natcore's liquid phase deposition (LPD) process,
or germanium quantum dots into layers using a process such as Natcore, which appears to be ideal for mass production,
which allowed them to observe directly the transitioning atomic configuration of a prototypical phase-change material, germanium telluride (Gete), under femtosecond laser pulses.
created using a special silicon-germanium mixture instead of pure silicon. Today's smallest transistors are 14nm in size
As well as replacing silicon with a silicon-germanium alloy, the technique also uses Extreme Ultraviolet (EUV) lithography to etch the microscopic patterns required into each chip.
International team of scientists constructs first germanium-tin semiconductor laser for silicon chips The transfer of data between multiple cores as well as between logic elements and memory cells is regarded as a bottleneck in the fast-developing computer technology.
In contrast semiconductors of main group IV--to which both silicon and germanium belong--can be integrated into the manufacturing process without any major difficulties.
That is why research groups all over the globe are intensively pursuing the objective of manipulating the material properties of germanium
The scientists at Julich's Peter Grunberg Institute have succeeded now for the first time in creating a real direct main group IV semiconductor laser by combining germanium and tin
That way we were able to demonstrate that the germanium-tin compound can amplify optical signals as well as generate laser light reports Dr. Hans Sigg from the Laboratory for Micro and Nanotechnology.
if microorganisms can lock up uranium that leached into the soil years ago and now makes well water in the area unsafe to drink.
the uranium becomes immobile, "said Lee Kerkhof, a professor of marine and coastal sciences in the School of Environmental and Biological sciences."
Breathing uranium is rather rare in the microbial world. Most examples of bacteria which can respire uranium cannot breathe oxygen
but often breathe compounds based on metals--typically forms of solid iron. Scientists had witnessed previously decreasing concentrations of uranium in groundwater
when iron-breathing bacteria were active, but they have yet to show that those iron-breathing bacteria were directly respiring the uranium.
While the chemical reaction that the bacteria perform on uranium is a common process known as"reduction,
"or the act of accepting electrons, Kerkhof said it's still a mystery how the reduced uranium produced by this microorganism ultimately behaves in the subsurface environment."
"It appears that they form uranium nanoparticles, "he said, but the mineralogy is still not well known
and will be the subject of ongoing research. The Rutgers team was able to isolate the uranium-breathing bacterium in the lab by recognizing that uranium in samples from the Rifle site could be toxic to microorganisms as well as humans.
The researchers looked for signs of bacterial activity when they gradually added small amounts of dissolved uranium at the right concentration back to the samples where uranium had become immobilized.
Once they found the optimal uranium concentrations, they were able to isolate the novel strain.
Exactly how the strain evolved Kerkhof said, "we are not sure.""But, he explained, bacteria have the ability to pass genes to each other.
this bacterium"picked up a genetic element that's now allowing it to detoxify uranium,
to actually grow on uranium.""His research team has completed sequencing its genome to support future research into the genetic elements that allow the bacterium to grow on uranium.
What Kerkhof is optimistic about is the potential for these bacteria to mitigate the specific groundwater pollution problem in Rifle.
Scientists at first expected the groundwater to flush into the Colorado river and carry the dissolved uranium with it,
it could be considered for other sites where uranium was processed for nuclear arsenals or power plant fuel. While the problem isn't widespread,
"There is depleted uranium in a lot of armor-piercing munitions, "he said, "so places like the Middle east that are experiencing war could be exposed to high levels of uranium in the groundwater
#Scientists find genetic variants key to understanding origins of ovarian cancer New research by an international team including Keck Medicine of USC scientists is bringing the origins of ovarian cancer into sharper focus.
material, germanium telluride (Gete), when it is hit by a femtosecond laser pulse. In UEC, a sample of crystalline Gete is bombarded with a femtosecond laser pulse,
The alliance sought to develop industry-first innovations, such as Silicon Germanium (Sige) channel transistors, and Extreme Ultraviolet (EUV) lithography integration at multiple levels.
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