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Archive for the ‘chemistry’ category: Page 289

Apr 9, 2020

Collisional cooling of ultracold molecules

Posted by in categories: chemistry, particle physics, quantum physics

Since the original work on Bose–Einstein condensation1,2, the use of quantum degenerate gases of atoms has enabled the quantum emulation of important systems in condensed matter and nuclear physics, as well as the study of many-body states that have no analogue in other fields of physics3. Ultracold molecules in the micro- and nanokelvin regimes are expected to bring powerful capabilities to quantum emulation4 and quantum computing5, owing to their rich internal degrees of freedom compared to atoms, and to facilitate precision measurement and the study of quantum chemistry6. Quantum gases of ultracold atoms can be created using collision-based cooling schemes such as evaporative cooling, but thermalization and collisional cooling have not yet been realized for ultracold molecules. Other techniques, such as the use of supersonic jets and cryogenic buffer gases, have reached temperatures limited to above 10 millikelvin7,8. Here we show cooling of NaLi molecules to micro- and nanokelvin temperatures through collisions with ultracold Na atoms, with both molecules and atoms prepared in their stretched hyperfine spin states. We find a lower bound on the ratio of elastic to inelastic molecule–atom collisions that is greater than 50—large enough to support sustained collisional cooling. By employing two stages of evaporation, we increase the phase-space density of the molecules by a factor of 20, achieving temperatures as low as 220 nanokelvin. The favourable collisional properties of the Na–NaLi system could enable the creation of deeply quantum degenerate dipolar molecules and raises the possibility of using stretched spin states in the cooling of other molecules.

Apr 9, 2020

Engineer uses metal-oxide nanomaterials deposited on cloth to wipe out microbes

Posted by in categories: biological, chemistry, engineering, health, nanotechnology, sustainability

In an effort to make highly sensitive sensors to measure sugar and other vital signs of human health, Iowa State University’s Sonal Padalkar figured out how to deposit nanomaterials on cloth and paper.

Feedback from a peer-reviewed paper published by ACS Sustainable Chemistry and Engineering describing her new fabrication technology mentioned the metal-oxide nanomaterials the assistant professor of mechanical engineering was working with—including , cerium oxide and copper oxide, all at scales down to billionths of a meter—also have .

“I might as well see if I can do something else with this technology,” Padalkar said. “And that’s how I started studying antimicrobial uses.”

Apr 3, 2020

D-Wave Systems

Posted by in categories: chemistry, quantum physics

200+ user-developed early quantum applications on D-Wave systems, including airline scheduling, election modeling, quantum chemistry simulation, automotive design, preventative healthcare, logistics, and much more.

Mar 25, 2020

Coronavirus: Nobel Prize winner predicts US will get through crisis sooner than expected

Posted by in categories: biotech/medical, chemistry

A Nobel Prize winning biology professor has provided a bit of good news amidst the coronavirus gloom; the US may see a downturn in new cases sooner than some models have predicted.

Michael Levitt, a Stanford University biology professor and a 2013 Nobel Prize winner in chemistry, said his models predict the virus is not likely to dwindle on for months or years and – most importantly – is not likely to cause millions of deaths.

Mr Levitt previously predicted – correctly – when China would experience and endure the worst of its coronavirus crisis.

Mar 17, 2020

Researchers set benchmark to determine achievement of quantum computing

Posted by in categories: chemistry, quantum physics, supercomputing

The race toward the first practical quantum computer is in full stride. Companies, countries, collaborators, and competitors worldwide are vying for quantum supremacy. Google says it’s already there. But what does that mean? How will the world know when it’s been achieved?

Using , at PNNL have set a mark that a quantum system would need to surpass to establish quantum supremacy in the realm of chemistry.

That’s because the fastest classical computers available today are getting better and better at simulating what a quantum computer will eventually be expected to do. To prove itself in the real world, a quantum computer will need to be able to outdo what a fast supercomputer can do. And that’s where the PNNL-led team have set a benchmark for quantum computers to beat.

Mar 7, 2020

Could quantum computing help beat the next coronavirus?

Posted by in categories: biotech/medical, chemistry, computing, quantum physics

Quantum computing isn’t yet far enough along that it could have helped curb the spread of this coronavirus outbreak. But this emerging field of computing will almost certainly help scientists and researchers confront future crises.

“Can we compress the rate at which we discover, for example, a treatment or an approach to this?” asks Dario Gil, the director of IBM Research. “The goal is to do everything that we are doing today in terms of discovery of materials, chemistry, things like that, (in) factors of 10 times better, 100 times better,”

And that, he says, “could be game-changing.”

Feb 27, 2020

How resident microbes restructure body chemistry

Posted by in categories: biotech/medical, chemistry, genetics, neuroscience

The team compared germ-free (sterile) mice and mice with normal microbes. They used a laboratory technique called mass spectrometry to characterize the non-living molecules in every mouse organ. They identified as many molecules as possible by comparing them to reference structures in the GNPS database, a crowdsourced mass spectrometry repository developed by Dorrestein and collaborators. They also determined which living microbes co-locate with these molecules by sequencing a specific genetic region that acts as a barcode for bacterial types.

In total, they analyzed 768 samples from 96 sites of 29 different organs from four germ-free mice and four mice with normal microbes. The result was a map of all of the molecules found throughout the body of a normal mouse with microbes, and a map of molecules throughout a mouse without microbes.

A comparison of the maps revealed that as much as 70 percent of a mouse’s gut chemistry is determined by its gut microbiome. Even in distant organs, such as the uterus or the brain, approximately 20 percent of molecules were different in the mice with gut microbes.

Feb 27, 2020

Scientists discover new clue behind age-related diseases and food spoilage

Posted by in categories: biotech/medical, chemistry, food, life extension

Scientists at the U.S. Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab) have made a surprising discovery that could help explain our risk for developing chronic diseases or cancers as we get older, and how our food decomposes over time.

What’s more, their findings, which were reported recently in the Proceedings of the National Academy of Sciences (PNAS), point to an unexpected link between the ozone chemistry in our atmosphere and our cells’ hardwired ability to ward off disease.

“The beauty of nature is that it often decides to use similar chemistries throughout a system, but we never thought that we would find a common link between atmospheric chemistry, and the chemistry of our bodies and food,” said Kevin Wilson, the deputy director of Berkeley Lab’s Chemical Sciences Division who led the study. “Our study is the first to explore another chemical pathway that might affect how well the cells in our bodies — and even our food — can respond to oxidative stress, such as pollution, over time.”

Feb 25, 2020

Five Scientific Discoveries Made in Dreams

Posted by in category: chemistry

“[Einstein] dreamt that he was riding a sled down a steep, snowy slope and, as he approached the speed of light in his dream, the colors all blended into one. He spent much of his career, inspired by that dream, thinking about what happens at the speed of light.”


By Tara MacIsaac, Epoch Times

In Beyond Science, Epoch Times explores research and accounts related to phenomena and theories that challenge our current knowledge. We delve into ideas that stimulate the imagination and open up new possibilities.

Continue reading “Five Scientific Discoveries Made in Dreams” »

Feb 24, 2020

Scientists Sculpt Nanoparticle Shells with Light

Posted by in categories: chemistry, nanotechnology, particle physics

For the first time, researchers have used light to control the shape of nanoparticles and create micron-size hollow shells from crystals of cuprous oxide (copper and oxygen). Such particles could have future applications as a low-cost catalyst to help pull excess carbon dioxide from the air, a way to improve microscopic imaging and more, says Bryce Sadtler, a chemist at Washington University in St. Louis and senior author of a study on the new method, published last October in Chemistry of Materials.


Hollowed-out microcrystals could lock away carbon.