Imagine filling up your gas tank with 10 gallons of gas, driving just far enough to burn a half gallon and discarding the rest. Then, repeat. That is essentially the practice that the U.S. nuclear industry is following.
Spent nuclear fuel from power plants still has 95% of its potential to produce electricity. Current plans are to dispose of the spent nuclear fuel in a geologic repository. So, why is it not recycled? It turns out that separating usable versus unusable parts of spent nuclear fuel is complicated.
“Spent nuclear fuel contains roughly half of the periodic table. So, from a chemistry standpoint, there’s a lot going on,” said Gregg Lumetta, PNNL chemist and laboratory fellow. “And to reduce proliferation risk, it is best if pure plutonium is not produced at any point in the separation process.”
Scientists dramatically enhance the achievable resolution at free-electron lasers with a new technique.
Hard X-ray free-electron lasers (XFELs) have delivered intense, ultrashort X-ray pulses for over a decade. One of the most promising applications of XFELs is in biology, where researchers can capture images down to the atomic scale even before the radiation damage destroys the sample. In physics and chemistry, these X-rays can also shed light on the fastest processes occurring in nature with a shutter speed lasting only one femtosecond – equivalent to a millionth of a billionth of a second.
However, on these minuscule timescales, it is extremely difficult to synchronize the X-ray pulse that sparks a reaction in the sample on the one hand and the laser pulse which ‘observes’ it on the other. This problem is called timing jitter, and it is a major hurdle in ongoing efforts to perform time-resolved experiments at XFELs with ever-shorter resolution.
Large swaths of U.S. military land are covered with munitions components, including the explosive chemical RDX. This molecule is toxic to people and can cause cancer. It also doesn’t naturally break down and can contaminate groundwater. Now researchers have genetically engineered a grass commonly used to fight soil erosion so that it can remove RDX from the soil, according to a new paper published May 3 in Nature Biotechnology.
A team, which includes researchers from the University of Washington, demonstrated that over the course of three years, a genetically engineered switchgrass could break down an explosive chemical in…
Organic transistors that can simulate basic synaptic functions and act as biomimetic devices are advantageous for next generation bioelectronics. Here, the authors realize non-volatile organic electrochemical transistors with optimized performance required for associative learning circuits.
Scientists used to perform experiments by stirring biological and chemical agents into test tubes.
Nowadays, they automate research by using microfluidic chips the size of postage stamps. In these tiny devices, millions of microscopic particles are captured in droplets of water, each droplet serving as the “test tube” for a single experiment. The chip funnels these many droplets, one at a time, through a tiny channel where a laser probes each passing droplet to record thousands of experimental results each second.
These chips are used for such things as testing new antibiotics, screening drug compounds, sequencing the DNA and RNA of single cells, and otherwise speeding up the pace of scientific discovery.
To combat this, Li and his team at Harvard have designed their solid-state battery with a multilayer approach that stacks its materials of varying stabilities between the anode and cathode. Much like a sandwich. This multi-material battery sandwich helps alleviate the penetration of lithium dendrites by controlling and containing them rather than preventing them altogether.
As you can see from the image above, the Harvard team has simplified its battery design to a form that’s more our speed. In this case, a BLT sandwich. The top slice of bread represents the lithium-metal anode, followed by lettuce appropriately representing a coating of graphite. The two layers of tomatoes represent the first electrolyte, protecting the delicious middle layer of bacon as the second electrolyte. Everything sits upon the bottom slice of bread, or the cathode. Is anyone else suddenly hungry for batteries?
In this design, dendrites are able to grow through the graphite (lettuce) and first electrolyte (tomato) but are halted when they reach the second electrolyte (bacon), thus preventing the dendrites from shorting the entire battery. This multilayer approach provokes chemistry that makes the second electrolyte too tight for the dendrites to penetrate. Furthermore, the Harvard researchers say this same chemistry can backfill the holes made by dendrites, essentially making the solid-state battery self-healing. Is there anything better than a sandwich that can regenerate itself? Honestly.
Nuclear Nonproliferation, Cooperative Threat Reduction and WMD Terrorism — Dr. Natasha Bajema, Director, Converging Risks Lab, The Council on Strategic Risks.
Dr. Natasha Bajema, is a subject matter expert in nuclear nonproliferation, cooperative threat reduction and WMD terrorism, and currently serves as Director of the Converging Risks Lab, at The Council on Strategic Risks, a nonprofit, non-partisan security policy institute devoted to anticipating, analyzing and addressing core systemic risks to security in the 21st century, with special examination of the ways in which these risks intersect and exacerbate one another.
The Converging Risks Lab (CRL) is a research and policy development-oriented program designed to study converging, cross-sectoral risks in a rapidly-changing world, which brings together experts from multiple sectors of the security community, to ask forward-thinking questions about these converging risks, and to develop anticipatory solutions.
Dr. Bajema is also Founder and CEO of Nuclear Spin Cycle, a publishing and production company specializing in national security, entertainment, and publishing.
Prior to this, Dr. Bajema was at the Center for the Study of Weapons of Mass Destruction at the National Defense University, serving as Director of the Program for Emerging Leaders (PEL), as well as serving long-term detail assignments serving in various capacities in the Office of the Secretary of Defense, Acquisitions, Technology and Logistics, Nuclear, Chemical and Biological Defense Programs and in Defense Nuclear Nonproliferation at Department of Energy’s National Nuclear Security Administration.
Only one in three fertilizations leads to a successful pregnancy. Many embryos fail to progress beyond early development. Cell biologists at the Max Planck Institute (MPI) for Biophysical Chemistry in Göttingen (Germany), together with researchers at the Institute of Farm Animal Genetics in Mariensee and other international colleagues, have now developed a new model system for studying early embryonic development. With the help of this system, they discovered that errors often occur when the genetic material from each parent combines immediately after fertilization. This is due to a remarkably inefficient process.
Human somatic cells typically have 46 chromosomes, which together carry the genetic information. These chromosomes are first brought together at fertilization, 23 from the father’s sperm, and 23 from the mother’s egg. After fertilization, the parental chromosomes initially exist in two separate compartments, known as pronuclei. These pronuclei slowly move towards each other until they come into contact. The pronuclear envelopes then dissolve, and the parental chromosomes unite.
The majority of human embryos, however, end up with an incorrect number of chromosomes. These embryos are often not viable, making erroneous genome unification a leading cause of miscarriage and infertility.
Do you like unusual clocks? We’re sure you’ll love this one!😍
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