| 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.
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
Thorium is an alternative to uranium as a way of doing nuclear fission he told Metro.
Thorium also produces less radioactive waste than uranium, waste which needs to be secured for hundreds rather than tens of thousands of years.
but when exposed to neutrons it will react to produce a particular isotope of uranium (U-233) that becomes the nuclear fuel.
and produces less waste than the usual uranium power plant reaction that generates plutonium, which can be used to make weapons.
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,
During it#3-month exploration it will search for natural resources and rare elements such as titanium and uranium.
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
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
#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,
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.
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