БЛОГ

Archive for the ‘chemistry’ category: Page 337

Nov 10, 2015

Next Big Future: Superconducting at −70 degrees celsius seems to be accepted

Posted by in categories: chemistry, materials, physics

The world of superconductivity is in uproar. Last year, Mikhail Eremets and a couple of pals from the Max Planck Institute for Chemistry in Mainz, Germany, made the extraordinary claim that they had seen hydrogen sulphide superconducting at −70 °C. That’s some 20 degrees hotter than any other material—a huge increase over the current record.

Eremets and co have worked hard to conjure up the final pieces of conclusive evidence. A few weeks ago, their paper was finally published in the peer reviewed journal Nature, giving it the rubber stamp of respectability that mainstream physics requires. Suddenly, superconductivity is back in the headlines.

Today, Antonio Bianconi and Thomas Jarlborg at the Rome International Center for Materials Science Superstripes in Italy provide a review of this exciting field. These guys give an overview of Eremet and co’s discovery and a treatment of the theoretical work that attempts to explain it.

Read more

Nov 3, 2015

Researchers create lithium-air battery that could be 10x more powerful than lithium-ion

Posted by in categories: chemistry, electronics, mobile phones, solar power, sustainability, transportation

A new lithium-air battery created by researchers at the University of Cambridge points the way to the ultimate battery packs of the future, its makers say. With a very high energy density, more than 90 percent efficiency and the capability for more than 2,000 recharge cycles, the new test battery could prove an important stepping stone in the development of this essential technology.

If you’re getting tired of announcements about breakthroughs in battery technology, that’s understandable: as they’re so essential to modern life, many teams of scientists are busy working on the problem around the clock, but it’s an incredibly complex area of chemistry. Any new battery has to improve on what we already have, be safe to use in consumer gadgets, and be commercially viable enough to be affordable for manufacturers.

Those are difficult targets to hit, and that’s why many ‘miracle’ batteries have since fallen by the wayside – once the initial lab work is done, proving concepts and scaling up production is very difficult to get right. The potential rewards are huge though, not just for smartphones but for electric cars and solar power, where batteries are essential for storing energy to use when the sun isn’t shining.

Read more

Sep 30, 2015

Can Our DNA Electromagnetically ‘Teleport’ Itself? One Researcher Thinks So

Posted by in categories: biotech/medical, chemistry

A Nobel prize winning scientist who shared the 2008 prize for medicine for his role in establishing the link between HIV and AIDS has stirred up a good deal of both interest and skepticism with his latest experimental results, which more or less show that DNA can teleport itself to distant cells via electromagnetic signals. If his results prove correct, they would shake up the foundations upon which modern chemistry rests. But plenty of Montagnier’s peers are far from convinced.

The full details of Montagnier’s experiments are not yet known, as his paper has not yet been accepted for publication. But he and his research partners have made a summary of his findings available. Essentially, they took two test tubes – one containing a fragment of DNA about 100 bases long, another containing pure water – and isolated them in a chamber that muted the earth’s natural electromagnetic field to keep it from muddying the results. The test tubes were housed within a copper coil emanating a weak electromagnetic field.

Several hours later, the contents of both test tubes were put through polymerase chain reactions to identify any remnants of DNA – a process that subjected the contents to enzymes that would make copies of any DNA fragments they found. According to Montagnier, the DNA was recovered from both tubes even though the second should have only contained water.

Read more

Sep 28, 2015

NASA confirms that liquid water flows on Mars

Posted by in categories: chemistry, humor, space

Liquid water exists on the surface of Mars during the planet’s warmer seasons, according to new research published in Nature Geosciences . This revelation comes from new spectral data gathered by NASA’s Mars Reconnaissance Orbiter (MRO), a spacecraft that studies the planet from orbit. The orbiter analyzed the chemistry of weird dark streaks that have been known to appear and disappear seasonally on the Martian surface. The analysis confirms that these streaks are formed by briny — or salty — water flowing downhill on Mars.

NASA has advertised these findings as the solution to a major Mars mystery: does the Red Planet truly have liquid water on its surface? Researchers have known that water exists in ice form on Mars, but it’s never been confirmed if water can remain in a liquid state. The space agency is claiming that we now have that answer.

This isn’t the first study to suggest liquid water is present in some form on Mars. Scientists have theorized for years that Mars was once home to a large ocean more than 4 billion years ago. And recent findings from the Mars Curiosity rover suggest that liquid water exists just underneath the Martian surface. The discovery of water on Mars has almost become a joke among planetary scientists. Alfred McEwen, a planetary geologist at Planetary Image Research Laboratory who also worked on this research, wrote in Scientific American that the studies have become extremely commonplace: “Congratulations — you’ve discovered water on Mars for the 1,000th time!” he joked.

Read more

Sep 26, 2015

The Chemistry Behind The Battery That Could Outperform Tesla’s Powerwall

Posted by in categories: chemistry, sustainability

A new type of battery could provide better storage for renewable energy than Tesla’s Powerwall. Here’s how it works.

Read more

Sep 22, 2015

Calculations with nanoscale smart particles

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

Researchers from the Institute of General Physics of the Russian Academy of Sciences, the Institute of Bioorganic Chemistry of the Russian Academy of Sciences and MIPT have made an important step towards creating medical nanorobots. They discovered a way of enabling nano- and microparticles to produce logical calculations using a variety of biochemical reactions.

Details of their are given in the journal Nature Nanotechnology. It is the first experimental publication by an exclusively Russian team in one of the most cited scientific magazines in many years.

The paper draws on the idea of computing using biomolecules. In electronic circuits, for instance, logical connectives use current or voltage (if there is voltage, the result is 1, if there is none, it’s 0). In biochemical systems, the result can a given substance.

Read more

Sep 21, 2015

Crystallizing the DNA nanotechnology dream: Scientists have designed the first large DNA crystals

Posted by in categories: biotech/medical, chemistry, computing, engineering, materials, nanotechnology

DNA has garnered attention for its potential as a programmable material platform that could spawn entire new and revolutionary nanodevices in computer science, microscopy, biology, and more. Researchers have been working to master the ability to coax DNA molecules to self assemble into the precise shapes and sizes needed in order to fully realize these nanotechnology dreams.

For the last 20 years, scientists have tried to design large DNA crystals with precisely prescribed depth and complex features – a design quest just fulfilled by a team at Harvard’s Wyss Institute for Biologically Inspired Engineering. The team built 32 DNA crystals with precisely-defined depth and an assortment of sophisticated three-dimensional (3D) features, an advance reported in Nature Chemistry.

The team used their “DNA-brick self-assembly” method, which was first unveiled in a 2012 Science publication when they created more than 100 3D complex nanostructures about the size of viruses. The newly-achieved periodic crystal structures are more than 1000 times larger than those discrete DNA brick structures, sizing up closer to a speck of dust, which is actually quite large in the world of DNA nanotechnology.

Read more

Sep 12, 2015

Scientists discover cause of and potential treatment for muscle weakness and loss due to aging

Posted by in categories: chemistry, life extension

As we grow older, we lose strength and muscle mass. However, the cause of age-related muscle weakness and atrophy has remained a mystery.

Scientists at the University of Iowa have discovered the first example of a protein that causes and loss during aging. The protein, ATF4, is a transcription factor that alters gene expression in , causing reduction of , strength, and mass. The UI study also identifies two natural compounds, one found in apples and one found in green tomatoes, which reduce ATF4 activity in aged skeletal muscle. The findings, which were published online Sept. 3 in the Journal of Biological Chemistry, could lead to new therapies for age-related muscle weakness and atrophy.

Read more

Sep 1, 2015

DNA-guided 3-D printing of human tissue is unveiled

Posted by in categories: 3D printing, biotech/medical, chemistry

A UCSF-led team has developed a technique to build tiny models of human tissues, called organoids, more precisely than ever before using a process that turns human cells into a biological equivalent of LEGO bricks. These mini-tissues in a dish can be used to study how particular structural features of tissue affect normal growth or go awry in cancer. They could be used for therapeutic drug screening and to help teach researchers how to grow whole human organs.

The new technique — called DNA Programmed Assembly of Cells (DPAC) and reported in the journal Nature Methods on August 31, 2015 — allows researchers to create arrays of thousands of custom-designed organoids, such as models of human mammary glands containing several hundred cells each, which can be built in a matter of hours.

There are few limits to the tissues this technology can mimic, said Zev Gartner, PhD, the paper’s senior author and an associate professor of pharmaceutical chemistry at UCSF. “We can take any cell type we want and program just where it goes. We can precisely control who’s talking to whom and who’s touching whom at the earliest stages. The cells then follow these initially programmed spatial cues to interact, move around, and develop into tissues over time.”

Read more

Aug 20, 2015

Scientists successfully grow human brain equivalent to 5-week-old foetus in the lab

Posted by in categories: chemistry, neuroscience

Growing brain tissue in a dish has been done before, but bold new research announced this week shows that scientists’ ability to create human brains in laboratory settings has come a long way quickly.

Researchers at the Ohio State University in the US claim to have developed the most complete laboratory-grown human brain ever, creating a model with the brain maturity of a 5-week-old foetus. The brain, which is approximately the size of a pencil eraser, contains 99 percent of the genes that would be present in a natural human foetal brain.

“It not only looks like the developing brain, its diverse cell types express nearly all genes like a brain,” Rene Anand, professor of biological chemistry and pharmacology at Ohio State and lead researcher on the brain model, said in a statement.

Read more