Archive for the ‘chemistry’ category: Page 5

Aug 5, 2022

Graphene oxide membranes reveal unusual behaviour of water at the nanoscale

Posted by in categories: chemistry, energy, nanotechnology

Do more pores in a sieve allow more liquid to flow through it? As material scientists have uncovered, this seemingly simple question may have an unexpected answer at the nanoscale—and it could have important implications in the development of water filtration, energy storage and hydrogen production.

Researchers from UNSW Sydney, University of Duisburg-Essen (Germany), GANIL (France) and Toyota Technological Institute (Japan) experimenting with Graphene Oxide (GO) membranes have discovered the opposite can occur at the nanoscopic level. The research, published in Nano Letters, shows the chemical environment of the sieve and the of the liquid play a surprisingly important role in permeability.

The researchers observed that a density of pores doesn’t necessarily lead to higher permeability—in other words, having more tiny holes doesn’t always allow water to flow through at the nanoscale. The study, supported by the European Union and Humboldt Research Foundation funding, shines new light on the mechanisms that govern water flow through GO membranes.

Aug 4, 2022

New method mass-produces antitumor cells to treat blood diseases and cancer

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

A Purdue University chemical engineer has improved upon traditional methods to produce off-the-shelf human immune cells that show strong antitumor activity, according to a paper published in the peer-reviewed journal Cell Reports.

Xiaoping Bao, a Purdue University assistant professor from the Davidson School of Chemical Engineering, said CAR-neutrophils, or chimeric antigen receptor neutrophils, and engraftable HSCs, or , are effective types of therapies for blood diseases and cancer. Neutrophils are the most abundant white cell blood type and effectively cross physiological barriers to infiltrate solid tumors. HSCs are specific progenitor that will replenish all blood lineages, including neutrophils, throughout life.

“These cells are not readily available for broad clinical or research use because of the difficulty to expand ex vivo to a sufficient number required for infusion after isolation from donors,” Bao said. “Primary neutrophils especially are resistant to genetic modification and have a short half-life.”

Aug 4, 2022

Yale-developed technology restores cell, organ function in pigs after death

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

Within minutes of the final heartbeat, a cascade of biochemical events triggered by a lack of blood flow, oxygen, and nutrients begins to destroy a body’s cells and organs. But a team of Yale scientists has found that massive and permanent cellular failure doesn’t have to happen so quickly.

The researchers stressed that additional studies are necessary to understand the apparently restored motor functions in the animals, and that rigorous ethical review from other scientists and bioethicists is required.

The experimental protocols for the latest study were approved by Yale’s Institutional Animal Care and Use Committee and guided by an external advisory and ethics committee.

Continue reading “Yale-developed technology restores cell, organ function in pigs after death” »

Aug 3, 2022

Researchers propose affordable and sustainable alternative to lithium-ion batteries

Posted by in categories: chemistry, energy, sustainability

Concerns regarding scarcity, high prices, and safety regarding the long-term use of lithium-ion batteries has prompted a team of researchers from Rensselaer Polytechnic Institute to propose a greener, more efficient, and less expensive energy storage alternative.

In research published recently in Proceedings of the National Academy of Science (PNAS), corresponding author Nikhil Koratkar, the John A. Clark and Edward T. Crossan Professor of Engineering at Rensselaer, and his team, assert that could be used as an alternative to lithium-ions in batteries because of its abundance and low cost.

“The vast majority of rechargeable battery products are based on lithium-ion technology, which is the gold standard in terms of performance,” said Dr. Koratkar. “However, the Achilles’ heel for lithium-ion technology is cost. Lithium is a limited resource on the planet, and its price has increased drastically in recent years. We are working on an inexpensive, abundant, safe, and sustainable battery chemistry that uses ions in an aqueous, water-based electrolyte.”

Aug 3, 2022

An engineering breakthrough using DNA could unlock the quantum computing revolution

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

Scientists from the University of Virginia School of Medicine and collaborators used the building blocks of life to potentially revolutionize electronics.

The scientists utilized DNA to guide a chemical reaction that would overcome the barrier to Little’s superconductor, which was once thought to be “insurmountable”, a press statement reveals.

Aug 3, 2022

Red mud is piling up. Can scientists figure out what to do with it?

Posted by in categories: chemistry, economics, food, sustainability

Practical and glamorous, aluminium is prized for making products from kitchen foil and beverage cans to Tesla Roadsters and aircraft. But the silvery metal—abundant, cheap, lightweight, and corrosion resistant—has a dark side: red mud. This brownish red slurry, a caustic mishmash of metal-and silicon-rich oxides, often with a dash of radioactive and rare earth elements, is what’s left after aluminum is extracted from ore. And it is piling up. Globally, some 3 billion tons of red mud are now stored in massive waste ponds or dried mounds, making it one of the most abundant industrial wastes on the planet. Aluminum plants generate an additional 150 million tons each year.

Red mud has become trouble looking for a place to happen. In 2010, an earthen dam at one waste pond in Hungary gave way, unleashing a 2-meter-high wall of red mud that buried the town of Ajka, killing 10 people and giving 150 severe chemical burns. (See more on the dangers posed by waste dams.) Even when red mud remains contained, its extreme alkalinity can leach out, poison groundwater, and contaminate nearby rivers and ecosystems. Such liabilities, as well as growing regulatory pressure on industry to develop sustainable practices, have catalyzed global efforts to find ways to recycle and reuse red mud. Some researchers are developing ways to extract the valuable rare earth metals, whereas others turn the mud into cement or bricks.

“There is hope here,” says Yiannis Pontikes, a mechanical engineer at KU Leuven. But economic and marketing hurdles remain, and “the clock is ticking” as regulators consider new controls, says Efthymios Balomenos, a metallurgical engineer at the National Technical University of Athens. “At some point we will not be able to produce waste. So, there is an urgent need to make changes.”

Continue reading “Red mud is piling up. Can scientists figure out what to do with it?” »

Aug 3, 2022

Visualising sigma orbitals opens path to new understanding of surface chemistry

Posted by in categories: chemistry, mapping

Photoemisssion orbital tomography extended beyond pi orbitals.


Experimentally-generated map of copper surface using photoemission orbital tomography (top left) and the projected densities of states of σ and π orbitals (top right). The bianthracene investigated in the study (bottom left) and maps of its σ orbitals (bottom middle, right)

Continue reading “Visualising sigma orbitals opens path to new understanding of surface chemistry” »

Aug 3, 2022

Cosmic Buckyballs Could Be The Source of Mysterious Infrared Light

Posted by in categories: chemistry, quantum physics

Scientists may have just tracked down the source of some mysterious infrared glows detected emanating from stars and clouds of interstellar dust and gas.

These Unidentified Infrared Emission (UIE) bands have baffled scientists for decades; according to a theoretical new work, at least some of these bands can be produced by highly ionized buckminsterfullerene, more commonly known as buckyballs.

“I am extremely honored to have played a part in the astonishingly complex quantum chemistry investigations undertaken by Dr Sadjadi that have led to these very exciting results,” said astrophysicist Quentin Parker of Hong Kong University’s Laboratory for Space Research.

Continue reading “Cosmic Buckyballs Could Be The Source of Mysterious Infrared Light” »

Aug 2, 2022

Newly-discovered chemical reactions could explain how life began on Earth

Posted by in category: chemistry

Read more about Newly-discovered chemical reactions could explain how life began on Earth on Devdiscourse.

Aug 1, 2022

Research finds mechanically driven chemistry accelerates reactions in explosives

Posted by in categories: chemistry, engineering, physics, supercomputing

Scientists at the Lawrence Livermore National Laboratory (LLNL) Energetic Materials Center and Purdue University Materials Engineering Department have used simulations performed on the LLNL supercomputer Quartz to uncover a general mechanism that accelerates chemistry in detonating explosives critical to managing the nation’s nuclear stockpile. Their research is featured in the July 15 issue of the Journal of Physical Chemistry Letters.

Insensitive high explosives based on TATB (1,3,5-triamino-2,4,6-trinitrobenzene) offer enhanced safety properties over more conventional explosives, but physical explanations for these safety characteristics are not clear. Explosive initiation is understood to arise from hotspots that are formed when a shockwave interacts with microstructural defects such as pores. Ultrafast compression of pores leads to an intense localized spike in temperature, which accelerates chemical reactions needed to initiate burning and ultimately . Engineering models for insensitive high explosives—used to assess safety and performance—are based on the hotspot concept but have difficulty in describing a wide range of conditions, indicating missing physics in those models.

Using large-scale atomically resolved reactive molecular dynamics supercomputer simulations, the team aimed to directly compute how hotspots form and grow to better understand what causes them to react.

Page 5 of 161First23456789Last