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Archive for the ‘chemistry’ category

Jun 6, 2020

For The First Time Ever, Scientists Have Created Hexagonal Salt

Posted by in categories: chemistry, sustainability, transportation

While it probably won’t make it to your dining table, a new scientific achievement might be able to help in everything from radar equipment to electric cars: scientists have been able to form salt, aka sodium chloride (NaCl), in a hexagonal shape.

This is work done at the smallest of scales, with researchers able to get a thin film of hexagonal salt to form on top of a layer of diamond, due to the chemical interaction of both film and diamond substrate – something the team actually predicted would happen in advance through simulations.

It’s the latest in a series of discoveries where scientists have been able to synthesise 2D materials with unusual crystal structures, and it’s partly this self-imposed restriction to two dimensions that is enabling new and exotic structures to be formed.

Jun 4, 2020

Scientists aim gene-targeting breakthrough against COVID-19

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

A team of scientists from Stanford University is working with researchers at the Molecular Foundry, a nanoscience user facility located at the Department of Energy’s Lawrence Berkeley National Laboratory (Berkeley Lab), to develop a gene-targeting, antiviral agent against COVID-19.

Last year, Stanley Qi, an assistant professor in the departments of bioengineering, and chemical and at Stanford University and his team had begun working on a technique called PAC-MAN—or Prophylactic Antiviral CRISPR in —that uses the gene-editing tool CRISPR to fight influenza.

But that all changed in January, when news of the COVID-19 pandemic emerged. Qi and his team were suddenly confronted with a mysterious new virus for which no one had a clear solution. “So we thought, ‘Why don’t we try using our PAC-MAN technology to fight it?’” said Qi.

Jun 4, 2020

Study reveals continuous pathway to building blocks of life

Posted by in categories: biological, chemistry

Researchers have long sought to understand the origins of life on Earth. A new study conducted by scientists at the Institute for Advanced Study, the Earth-Life Science Institute (ELSI), and the University of New South Wales, among other participating institutions, marks an important step forward in the effort to understand the chemical origins of life. The findings of this study demonstrate how “continuous reaction networks” are capable of producing RNA precursors and possibly ultimately RNA itself — a critical bridge to life.

The paper is published in the Proceedings of the National Academy of Sciences.

While many of the mechanisms that propagate life are well understood, the transition from a prebiotic Earth to the era of biology remains shrouded in mystery. Previous experiments have demonstrated that simple organic compounds can be produced from the reactions of chemicals understood to exist in the primitive Earth environment. However, many of these experiments relied on coordinated experimenter interventions. This study goes further by employing a model that is minimally manipulated to most accurately simulate a natural environment.

Jun 4, 2020

Joined nano-triangles pave the way to magnetic carbon materials

Posted by in categories: chemistry, nanotechnology, particle physics

Graphene, a two-dimensional honeycomb structure made of carbon atoms with a thickness of only one atom, has numerous outstanding properties. These include enormous mechanical resistance and extraordinary electronic and optical properties. Last year a team led by the Empa researcher Roman Fasel was able to show that it can even be magnetic: they succeeded in synthesizing a molecule in the shape of a bowtie, which has special magnetic properties.

Now, researchers report another breakthrough. Theoretical work from 2007 predicted that graphene could exhibit if it were cut into tiny triangles. Over the last three years, several teams, including the Empa team, have succeeded in producing the so-called triangulenes, consisting of only a few dozen , by chemical synthesis under ultra-high vacuum.

Jun 3, 2020

Handheld UV Light Devices That Kill COVID-19, Other Viruses May Soon Be As Common As Phone, Keys

Posted by in categories: biotech/medical, chemistry, mobile phones

UNIVERSITY PARK, Pa. — Phone, keys, wallet…ultraviolet light device. Just in case you wanted yet another item to carry around all day, researchers say that portable, handheld COVID-19 killing ultraviolet light devices may be a reality in the future. These gadgets would emit high-intensity ultraviolet light and quickly disinfect targeted areas.

There are two main ways to clean and remove bacteria and viruses from a given surface: chemicals and ultraviolet (UV) radiation exposure. UV radiation between 200 and 300 nanometers can effectively kill a virus and stop it from replicating itself. Obviously, devices emitting UV rays would come in handy these days due to COVID-19, but as of now such devices require an expensive, bulky mercury-containing gas discharge lamp with a short battery life.

The study’s authors, however, believe that much more portable, longer lasting, energy efficient, and environmentally friendly UV light emitting diodes can be developed. The necessary LEDs already exist, but the process has been complicated by the fact that electrode materials must also be transparent.

Continue reading “Handheld UV Light Devices That Kill COVID-19, Other Viruses May Soon Be As Common As Phone, Keys” »

Jun 2, 2020

A plague of magnetic spots among the hot stars of globular clusters

Posted by in categories: chemistry, cosmology, evolution

For more than six decades, the quest to understand the formation of hot (about 20,000−30,000 K) extreme horizontal branch (EHB) stars in Galactic globular clusters has remained one of the most elusive in stellar evolutionary theory. Here we report on two discoveries that challenge the idea of the stable luminosity of EHB stars. The first mode of EHB variability is periodic and cannot be ascribed to either binary evolution or pulsation. Instead, we attribute it here to the presence of magnetic spots: superficial chemical inhomogeneities whose projected rotation induces the variability. The second mode of EHB variability is aperiodic and manifests itself on timescales of years. In two cases, six-year-long light curves display superflare events that are several million times more energetic than solar analogues. We advocate a scenario in which the two EHB variability phenomena are different manifestations of diffuse, dynamo-generated, weak magnetic fields. Magnetism is therefore a key player driving the formation and evolution of EHB clusters stars and, likewise, operating in the Galactic field counterparts. Our conclusions bridge similar variability/magnetism phenomena in all radiative-enveloped hot-stars: young main-sequence stars, old EHBs and defunct white dwarfs.

Jun 2, 2020

Killing coronavirus with handheld ultraviolet light device may be feasible

Posted by in categories: biotech/medical, chemistry

A personal, handheld device emitting high-intensity ultraviolet light to disinfect areas by killing the novel coronavirus is now feasible, according to researchers at Penn State, the University of Minnesota and two Japanese universities.

There are two commonly employed methods to sanitize and disinfect areas from bacteria and viruses—chemicals or ultraviolet radiation exposure. The UV radiation is in the 200 to 300 nanometer range and known to destroy the virus, making the virus incapable of reproducing and infecting. Widespread adoption of this efficient UV approach is much in demand during the current pandemic, but it requires UV radiation sources that emit sufficiently high doses of UV light. While devices with these high doses currently exist, the UV radiation source is typically an expensive mercury-containing gas discharge lamp, which requires high power, has a relatively short lifetime, and is bulky.

The solution is to develop high-performance, UV light emitting diodes, which would be far more portable, long-lasting, energy efficient and environmentally benign. While these LEDs exist, applying a current to them for light emission is complicated by the fact that the also has to be transparent to UV light.

Jun 1, 2020

Extra salty sodium battery performs on par with lithium

Posted by in categories: chemistry, energy

Batteries that use a sodium-ion chemistry rather than the commonplace lithium-ion could offer a number of advantages, owing to the cheap and abundant nature of the element. Scientists at Washington State University have come up with a design billed as a potential game changer in this area – a sodium-ion battery offering a comparable energy capacity and cycling ability to some lithium-ion batteries already on the market.

In a way, sodium-ion batteries function just like lithium-ion batteries, generating power by bouncing ions between a pair of electrodes in a liquid electrolyte. One of the problems with them in their current form, however, is that while this is going on inactive sodium crystals tend to build up on the surface of the negatively-charged electrode, the cathode, which winds up killing the battery. Additionally, sodium-ion batteries don’t hold as much energy as their lithium-ion counterparts.

“The key challenge is for the battery to have both high energy density and a good cycle life,” says Washington State University’s Junhua Song, lead author on the paper.

Jun 1, 2020

Researchers Propose New Diamond Nanostructure For Efficient Energy Storage

Posted by in categories: chemistry, computing, cyborgs, nanotechnology, sustainability

One of the biggest challenges for renewable energy research is energy storage. The goal is to find a material with high energy storage capacity and energy storage material with high storage capacity that can also quickly and efficiently discharge a large amount of energy. In an attempt to overcome this hurdle, researchers at the Queensland University of Technology (QUT) have proposed a brand-new carbon nanostructure designed to store energy in mechanical form.

Most portable energy storage devices currently rely on storing energy in chemical form such as batteries, however this proposed new structure, made from a bundle of diamond nanothread (DNT) does not suffer from the same limiting properties as batteries, such as temperature sensitivity, or the potential to leak or explode. I have previously written about carbon nanotubes, and their applications in everything from Batman-like artificial muscle, to an analogy of the fictional element Vibranium, but a lot of research around carbon nanotubes is already focused on energy harvesting and energy storage applications.

What makes this energy storage method different is the method by which energy is stored, and also the related increased robustness of the resultant material. Dr Haifei Zhan and his team at the QUT Centre for material science used computer modelling to propose the structure of these ultra-thin one-dimensional carbon threads. The theory is that these threads should be able to store energy when they are twisted or stretched, similar to the way we store energy in wind-up toys. By turning the key, we force the spring inside into a tight coil. Once the key is released, the coil wishes to release the extra tension held within it and begins to unfurl. In doing so it transfers that mechanical energy into the movement of the toy’s wheels.

Continue reading “Researchers Propose New Diamond Nanostructure For Efficient Energy Storage” »

Jun 1, 2020

‘Black nitrogen’: Researchers discover new high-pressure material and solve a puzzle of the periodic table

Posted by in categories: chemistry, materials

In the periodic table of elements there is one golden rule for carbon, oxygen and other light elements: Under high pressures, they have similar structures to heavier elements in the same group of elements. But nitrogen always seemed unwilling to toe the line. However, high-pressure chemistry researchers of the University of Bayreuth have disproved this special status. Out of nitrogen, they created a crystalline structure which, under normal conditions, occurs in black phosphorus and arsenic. The structure contains two-dimensional atomic layers, and is therefore of great interest for high-tech electronics. The scientists have presented this “black nitrogen” in Physical Review Letters.

Nitrogen—an exception in the periodic system?

When you arrange the chemical elements in ascending order according to their number of protons and look at their properties, it soon becomes obvious that certain properties recur at large intervals (periods). The brings these repetitions into focus. Elements with similar properties are placed one below the other in the same column, and thus form a group of elements. At the top of a column is the element that has the fewest protons and the lowest weight compared to the other group members. Nitrogen heads element group 15, but was previously considered the “black sheep” of the group. The reason: In earlier experiments, showed no structures similar to those exhibited under normal conditions by the of this group—specifically, phosphorus, arsenic and antimony. Instead, such similarities are observed at high pressures in the neighboring groups headed by carbon and oxygen.

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