БЛОГ

Archive for the ‘chemistry’ category: Page 305

Nov 14, 2019

Scientists synthesize light with new intrinsic chirality to tell mirror molecules apart

Posted by in categories: biotech/medical, chemistry

Light is the fastest way to distinguish right- and left-handed chiral molecules, which has important applications in chemistry and biology. However, ordinary light only weakly senses molecular handedness. Researchers from the Max Born Institute for Nonlinear Optics and Short Pulse Spectroscopy (MBI), the Israel Institute of Technology (Technion) and Technische Universitaet Berlin (TU Berlin) now report a method to generate and characterize synthetic chiral light, which identifies molecules’ handedness exceptionally distinctly. The results of their joint work have just appeared in Nature Photonics.

Like left and right hands, some molecules in nature have mirror twins. However, while these twin molecules may look similar, some of their properties can be very different. For instance, the handedness—or chirality—of molecules plays an essential role in chemistry, biology, and drug development. While one type of a molecule can cure a disease, its mirror twin—or enantiomer—may be toxic or even lethal.

It is extremely hard to tell opposite apart because they look identical and behave identically unless they interact with another chiral object. Light has long been used to detect chirality—oscillations of the electromagnetic field draw a chiral helix in space along the light propagation direction. Depending on whether the helix twirls clockwise or counterclockwise, the light wave is either right- or left-handed. However, the helix pitch, set by the light wavelength, is about 1000 times bigger than the size of a molecule. So the light helix is a gigantic circle compared to the tiny molecules, which hardly react to its chirality.

Nov 14, 2019

Magnets sustainably separate mixtures of rare earth metals

Posted by in categories: chemistry, computing, economics, mobile phones

A new study describes a novel approach for purifying rare earth metals, crucial components of technology that require environmentally-damaging mining procedures. By relying on the metal’s magnetic fields during the crystallization process, researchers were able to efficiently and selectively separate mixtures of rare earth metals.

Seventy-five of the ’s 118 elements are carried in the pockets and purses of more than 100 million U.S. iPhone users every day. Some of these elements are abundant, like silicon in computer chips or aluminum for cases, but certain metals that are required for crisp displays and clear sounds are difficult to obtain. Seventeen elements known as are crucial components of many technologies but are not found in concentrated deposits, and, because they are more dispersed, require toxic and environmentally-damaging procedures to extract.

With the goal of developing better ways to recycle these metals, new research from the lab of Eric Schelter describes a new approach for separating mixtures of rare earth metals with the help of a . The approach, published in Angewandte Chemie International Edition, saw a doubling in separation performance and is a starting point towards a cleaner and more circular rare earth metals economy.

Nov 11, 2019

How Long Before Sodium Batteries Are Worth Their Salt?

Posted by in categories: chemistry, computing, mobile phones, transportation

Circa 2017


Today, lithium is the active ingredient in batteries that power smart phones, laptops, and cars. But because of the price of lithium, researchers have been looking for another, more abundant element that could replace it. Several start-ups and established companies have tackled the idea of developing rechargeable batteries in which the active ingredient is sodium, lithium’s neighbor on the periodic table.

Besides its availability, sodium has several other important properties—not the least of which is its resistance to catching on fire. What’s more, “It was a good candidate because it could store a similar amount of energy as compared to lithium,” remembers Minah Lee, who does research on sodium batteries at Stanford University.

Continue reading “How Long Before Sodium Batteries Are Worth Their Salt?” »

Nov 11, 2019

DNA is only one among millions of possible genetic molecules

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

Biology encodes information in DNA and RNA, which are complex molecules finely tuned to their functions. But are they the only way to store hereditary molecular information? Some scientists believe life as we know it could not have existed before there were nucleic acids, thus understanding how they came to exist on the primitive Earth is a fundamental goal of basic research. The central role of nucleic acids in biological information flow also makes them key targets for pharmaceutical research, and synthetic molecules mimicking nucleic acids form the basis of many treatments for viral diseases, including HIV. Other nucleic acid-like polymers are known, yet much remains unknown regarding possible alternatives for hereditary information storage. Using sophisticated computational methods, scientists from the Earth-Life Science Institute (ELSI) at the Tokyo Institute of Technology, the German Aerospace Center (DLR) and Emory University explored the “chemical neighbourhood” of nucleic acid analogues. Surprisingly, they found well over a million variants, suggesting a vast unexplored universe of chemistry relevant to pharmacology, biochemistry and efforts to understand the origins of life. The molecules revealed by this study could be further modified to gives hundreds of millions of potential pharmaceutical drug leads.

Nucleic acids were first identified in the 19th century, but their composition, biological role and function were not understood by scientists until the 20th century. The discovery of DNA’s double-helical structure by Watson and Crick in 1953 revealed a simple explanation for how biology and evolution function. All living things on Earth store information in DNA, which consists of two polymer strands wrapped around each other like a caduceus, with each strand being the complement of the other. When the strands are pulled apart, copying the complement on either template results in two copies of the original. The DNA polymer itself is composed of a sequence of “letters,” the bases adenine (A), guanine (G), cytosine © and thymine (T), and living organisms have evolved ways to make sure during DNA copying that the appropriate sequence of letters is almost always reproduced. The sequence of bases is copied into RNA by proteins, which then is read into a protein sequence.

Nov 7, 2019

Celebrating Two Women In Science — Marie Curie And Lise Meitner

Posted by in categories: chemistry, life extension, science

Both Marie Curie and Lise Meitner, the only two women to be immortalized on the Periodic Table, celebrate the same November 7 birthday. Here are more reasons why they’re remarkable.

Nov 6, 2019

Theoretical spin battery could see magnet powered cars

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

Circa 2009


March 19, 2009 Researchers at the University of Miami and at the Universities of Tokyo and Tohoku, Japan, have been able to prove the existence of a “spin battery,” that could have significant applications including much faster, less expensive and use less energy consuming computer hard drives with no moving parts, and could even be developed to power cars.

A “spin battery” is “charged” by applying a large magnetic field to nano-magnets in a device called a magnetic tunnel junction (MTJ). Like a toy car, the spin battery is “wound up” by applying a large magnetic field — no chemistry involved.

Continue reading “Theoretical spin battery could see magnet powered cars” »

Nov 4, 2019

Scientists develop industrial-strength adhesive which can be unstuck in magnetic field

Posted by in categories: chemistry, mobile phones, sustainability, transportation

Researchers at the University of Sussex have developed a glue which can unstick when placed in a magnetic field, meaning products otherwise destined for landfill, could now be dismantled and recycled at the end of their life.

Currently, items like mobile phones, microwaves and car dashboards are assembled using adhesives. It is a quick and relatively cheap way to make products but, due to problems dismantling the various materials for different recycling methods, most of these products will be destined for landfill.

However, Dr. Barnaby Greenland, Lecturer in Medicinal Chemistry, working in conjunction with Stanelco RF Technologies Ltd and Prof Wayne Hayes at the University of Reading, may have found a solution.

Oct 29, 2019

Advances in anti-ageing research: how chemistry could hold the key to better health

Posted by in categories: chemistry, life extension

Has the chemistry of ageing come of age?

Oct 27, 2019

Scientists say solar technology may detect, attack cancer cells

Posted by in categories: biotech/medical, chemistry, solar power, sustainability

A study claims a new way to detect and attack cancer cells using technology traditionally reserved for solar power as the results showcased dramatic improvements.

The results published in Scientific Reports said that dramatic improvements were seen in light-activated fluorescent dyes for disease diagnosis, image-guided surgery and site-specific tumor treatment.

“We’ve tested this concept in breast, lung cancer and skin cancer cell lines and mouse models, and so far it’s all looking remarkably promising,” said Sophia, Michigan State University’s (MSU) biochemistry and molecular biologist.

Oct 26, 2019

Lattice QCD Calculations Predict Exotic Nuclei Not on Periodic Table

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

Have you ever wondered how the Sun creates the energy that we get from it every day and how the other elements besides hydrogen have formed in our universe? Perhaps you know that this is due to fusion reactions where four nuclei of hydrogen join together to produce a helium nucleus. Such nucleosynthesis processes are possible solely due to the existence, in the first place, of stable deuterons, which are made up of a proton and a neutron.

Probing deeper, one finds that a deuteron consists of six light quarks. Interestingly, the strong interaction between quarks, which brings stability to deuterons, also allows for various other six-quark combinations, leading to the possible formation of many other deuteron-like nuclei. However, no such nuclei, though theoretically speculated about and searched for experimentally many times, have yet been observed.

All this may get changed with an exciting new finding, where, using a state-of-the-art first-principles calculation of lattice quantum chromodynamics (QCD), the basic theory of strong interactions, a definite prediction of the existence of other deuteron-like nuclei has been made by TIFR’s physicists. Using the computational facility of the Indian Lattice Gauge Theory Initiative (ILGTI), Prof. Nilmani Mathur and postdoctoral fellow Parikshit Junnarkar in the Department of Theoretical Physics have predicted a set of exotic nuclei, which are not to be found in the Periodic Table. The masses of these new exotic nuclei have also been calculated precisely.