Lifeboat Foundation: Safeguarding Humanity
Toggle light / dark theme

Blog

Category: chemistry – Page 252

Substances trapped in nanobubbles exhibit unusual properties

Skoltech scientists modeled the behavior of nanobubbles appearing in van der Waals heterostructures and the behavior of substances trapped inside the bubbles. In the future, the new model will help obtain equations of state for substances in nano-volumes, opening up new opportunities for the extraction of hydrocarbons from rock with large amounts of micro-and nanopores. The results of the study were published in the Journal of Chemical Physics.

The van der Waals nanostructures hold much promise for the study of tiniest samples with volumes from 1 cubic micron down to several cubic nanometers. These atomically thin layers of two-dimensional materials, such as graphene, (hBN) and dichalcogenides of transition metals, are held together by weak van der Waals interaction only. Inserting a sample between the layers separates the upper and bottom layers, making the upper layer lift to form a nanobubble. The resulting will then become available for transmission electron and , providing an insight into the structure of the substance inside the bubble.

The properties exhibited by inside the van der Waals nanobubbles are quite unusual. For example, water trapped inside a nanobubble displays a tenfold decrease in its dielectric constant and etches the diamond surface, something it would never do under normal conditions. Argon which typically exists in when in large quantities can become solid at the same pressure if trapped inside very small nanobubbles with a radius of less than 50 nanometers.

Physicists make molecular vibrations more detectable

In molecules, the atoms vibrate with characteristic patterns and frequencies. Vibrations are therefore an important tool for studying molecules and molecular processes such as chemical reactions. Although scanning tunneling microscopes can be used to image individual molecules, their vibrations have so far been difficult to detect.

Physicists at Kiel University (Christian-Albrechts-Universität zu Kiel, CAU) have now invented a method with which the vibration signals can be amplified by up to a factor of 50. Furthermore, they increased the frequency resolution considerably. The new method will improve the understanding of interactions in molecular systems and further simulation methods. The research team has now published the results in the journal Physical Review Letters.

The discovery by Dr. Jan Homberg, Dr. Alexander Weismann and Prof. Dr. Richard Berndt from the Institute of Experimental and Applied Physics, relies on a special quantum mechanical effect, so-called “inelastic tunneling”. Electrons that pass through a molecule on their way from a metal tip to the substrate surface in the scanning tunneling microscope can release energy to the molecule or take energy up from it. This occurs in portions determined by the properties of the respective molecule.

Energy storage materials built from nano-sized molecular blocks

Molecules of the rare metallic element niobium can be used as molecular building blocks to design electrochemical energy storage materials. Mark Rambaran, Department of Chemistry at Umeå University, presents in his thesis a method for producing solid materials from aqueous solutions containing nano-sized niobium molecules, called polyoxoniobates.

“These polyoxoniobates are water-soluble and can be synthesized in large volumes. They act as , in the same way as when a child stacks Lego bricks,” Mark Rambaran says. “They can be used to make a wide range of materials, including supercapacitors that facilitate lithium-ion storage.”

Synthesis of polyoxoniobates can be done with microwave irradiation, because it is a rapid and efficient alternative to conventional hydrothermal methods, Mark Rambaran shows in his thesis.

Traditional computers can solve some quantum problems

There has been a lot of buzz about quantum computers and for good reason. The futuristic computers are designed to mimic what happens in nature at microscopic scales, which means they have the power to better understand the quantum realm and speed up the discovery of new materials, including pharmaceuticals, environmentally friendly chemicals, and more. However, experts say viable quantum computers are still a decade away or more. What are researchers to do in the meantime?

A new Caltech-led study in the journal Science describes how tools, run on , can be used to make predictions about and thus help researchers solve some of the trickiest physics and chemistry problems. While this notion has been shown experimentally before, the new report is the first to mathematically prove that the method works.

“Quantum computers are ideal for many types of physics and materials science problems,” says lead author Hsin-Yuan (Robert) Huang, a graduate student working with John Preskill, the Richard P. Feynman Professor of Theoretical Physics and the Allen V. C. Davis and Lenabelle Davis Leadership Chair of the Institute for Quantum Science and Technology (IQIM). “But we aren’t quite there yet and have been surprised to learn that classical machine learning methods can be used in the meantime. Ultimately, this paper is about showing what humans can learn about the physical world.”

Neuroimaging study suggests mental fatigue helps preserve the chemical integrity of the brain

Strenuous cognitive work leads to an accumulation of glutamate in the prefrontal cortex, according to new research published in the journal Current Biology. The new findings suggest that mental fatigue is a neuropsychological mechanism that helps to avert the build up of potentially toxic byproducts of prolonged cognitive activity.

“Nobody knows what mental fatigue is, how it is generated and why we feel it,” said study author Antonius Wiehler, a member of the Motivation, Brain and Behavior Lab at Pitié Salpêtrière Hospital in Paris. “It has remained a mystery despite more than a century of scientific research. Machines can do cognitive tasks continuously without fatigue, the brain is different and we wanted to understand how and why. Mental fatigue has important consequences: for economic decisions, for management at work, for education at school, for clinical cure, etc.”

The researchers were particularly interested in the role of glutamate, an excitatory neurotransmitter that is involved in a variety of cognitive functions, including learning and memory. In addition, glutamate plays a role in controlling the strength of synaptic connections. Too much or too little glutamate can lead to neuronal dysfunction, so it is critical that this neurotransmitter is tightly regulated.

JWST observes Earendel — the most distant star known — 12.8 billion ly away | Night Sky News Sep ‘22

For Physics & Chemistry experiments for kids delivered to your door head to https://melscience.com/sBIs/ and use promo code DRBECKY50 for 50% off the first month of any subscription (valid until 22nd October 2022).

To find out whether you can see the partial solar eclipse on 25th October 2022 put in your location here: https://www.timeanddate.com/eclipse/map/2022-october-25

To watch the next launch attempt for Artemis live at 6pm EST on Tuesday 27th September head to @NASA ‘s YouTube channel here: https://www.youtube.com/watch?v=CMLD0Lp0JBg.
To watch the DART mission impact live on Monday 26th September 2022 head to @NASA ‘s YouTube channel here: https://www.youtube.com/watch?v=4RA8Tfa6Sck.
My previous video on the DART mission: https://youtu.be/ZBhTtaTGhao.
My previous video on whether aliens exist (inc. Drake equation): https://www.youtube.com/watch?v=fihVzPl7Dys.
My previous Night Sky News debunking these JWST Big Bang Theory claims: https://www.youtube.com/watch?v=Fqfap3v0xxw.
My previous video chatting with Dr. Libby Jones about being in control of JWST: https://www.youtube.com/watch?v=UPO8pw8r7ak.
My previous video on the discovery of the star Earendel: https://www.youtube.com/watch?v=VChgsXbIgdw.
Welch et al. (2022; Earendel imaged with JWST — not peer reviewed) — https://arxiv.org/pdf/2208.09007.pdf.
Welch et al. (2022; Earendel discovered with HST — behind pay wall) — https://www.nature.com/articles/s41586-022-04449-y.
Carter et al. (2022; JWST direct image exoplanet HIP 65426b — not peer reviewed) — https://arxiv.org/pdf/2208.14990.pdf.
El Baldry et al. (2022; a black hole orbiting a Sun-like star — not peer reviewed) — https://arxiv.org/pdf/2209.06833.pdf.

PDRs4ALL project (that imaged the Orion nebula with JWST) — https://pdrs4all.org/

00:00 — Introduction.
00:40 — Fireball meteor across Ireland & Scotland.
01:35 — Draconids & Orionids Meteor Shower.
03:05 — Mars, Jupiter & Saturn visible right now.
03:39 — Jupiter at Opposition 26th September.
04:27 — Partial Solar Eclipse 25th October 2022
06:13 — Artemis launch rescheduled.
07:08 — DART mission asteroid impact imminent.
07:48 — RIP Frank Drake 1930–2022
08:25 — JWST misinformation AGAIN
09:39 — JWST confirms Earendel is a star (or binary star system)
13:31 — JWST’s first direct image of an exoplanet HIP 65426b explained.
17:07 — JWST observes Orion nebula.
19:39 — New candidate for closest black hole (its orbiting a Sun-like star too!)
23:59 — Outro.
24:26 — MEL science.
26:17 — Bloopers.

📚 My new book, “A Brief History of Black Holes”, out NOW in hardback, e-book and audiobook (which I narrated myself!) Note, USA & Canada hardback out 1st November 2022: http://hyperurl.co/DrBecky.

Continue reading “JWST observes Earendel — the most distant star known — 12.8 billion ly away | Night Sky News Sep ‘22” | >

New method allows scientists to determine all the molecules present in the lysosomes of mice

Small but mighty, lysosomes play a surprisingly important role in cells despite their diminutive size. Making up only 1–3% of the cell by volume, these small sacs are the cell’s recycling centers, home to enzymes that break down unneeded molecules into small pieces that can then be reassembled to form new ones. Lysosomal dysfunction can lead to a variety of neurodegenerative or other diseases, but without ways to better study the inner contents of lysosomes, the exact molecules involved in diseases—and therefore new drugs to target them—remain elusive.

A new method, reported in Nature on Sept. 21, allows scientists to determine all the molecules present in the lysosomes of any cell in mice. Studying the contents of these molecular recycling centers could help researchers learn how the improper degradation of cellular materials leads to certain diseases. Led by Stanford University’s Monther Abu-Remaileh, institute scholar at Sarafan ChEM-H, the study’s team also learned more about the cause for a currently untreatable neurodegenerative known as Batten disease, information that could lead to new therapies.

“Lysosomes are fascinating both fundamentally and clinically: they supply the rest of the cell with nutrients, but we don’t always know how and when they supply them, and they are the places where many diseases, especially those that affect the brain, start,” said Abu-Remaileh, who is an assistant professor of chemical engineering and of genetics.

Dr. Andrew Hebbeler, Ph.D. — Office of Science and Technology Policy (OSTP) — The White House

Maximizing Benefits Of The Life Sciences & Health Tech For All Americans — Dr. Andrew Hebbeler, Ph.D., Principal Assistant Director for Health and Life Sciences, Office of Science and Technology Policy, The White House.

Dr. Andrew Hebbeler, Ph.D., is Principal Assistant Director for Health and Life Sciences, Office of Science and Technology Policy at The White House (https://www.whitehouse.gov/ostp/ostps-teams/health-and-life-sciences/), and has extensive foreign affairs, national security, global health, and science and technology (S&T) policy experience.

Most recently, Dr. Hebbeler was Senior Director and Lead Scientist for Global Biological Policy and Programs at the non-profit Nuclear Threat Initiative and previous to that served in leadership positions at the State Department’s offices of Science and Technology Cooperation (OES/STC), the Science and Technology Adviser to the Secretary of State (E/STAS), and Cooperative Threat Reduction (ISN/CTR).

From 2013–2015, Dr. Hebbeler was Assistant Director for Biological and Chemical Threats at the Obama White House Office of Science and Technology Policy where he oversaw American S&T efforts to combat infectious disease and chemical weapon threats.

Prior to his White House position, Dr. Hebbeler led the State Department’s Biosecurity Engagement Program, a $40M program that prevents terrorist access to potentially dangerous biological materials and dual-use infrastructure and expertise, while supporting efforts to combat infectious disease and enhance public and animal health worldwide.

Continue reading “Dr. Andrew Hebbeler, Ph.D. — Office of Science and Technology Policy (OSTP) — The White House” | >

We did it! Harmful chemicals in the ozone layer drop by 50%, NOAA says

Recovery of the Antarctic ozone layer is anticipated to take place sometime around 2070.

The depletion of the ozone layer had a huge impact on humanity for a while. Moreover, the United Nations accepted The International Day for the Preservation of the Ozone Layer in 1994.

Every living thing on Earth is shielded from UV radiation by the stratospheric ozone layer. Thus, the Ozone Layer is vital for all forms of life, and we need to protect it without a doubt.

Engineered Cells Become Drug Factories with Avian Assistance

The genetic encoding of ncAAs with distinct chemical, biological, and physical properties requires the engineering of bioorthogonal translational machinery, consisting of an evolved aminoacyl-tRNA synthetase/tRNA pair and a “blank” codon. To achieve this, the researchers mimicked the ibis’ ability to synthesize sTyr and incorporate it into proteins.

The Xiao lab employed a mutant amber stop codon to encode the desired sulfotransferase, resulting in a completely autonomous mammalian cell line capable of biosynthesizing sTyr and incorporating it with great precision into proteins.

These engineered cells, the authors wrote, can produce “site-specifically sulfated proteins at a higher yield than cells fed exogenously with the highest level of sTyr reported in the literature.” They used the cells to prepare highly potent thrombin inhibitors with site-specific sulfation.