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Archive for the ‘chemistry’ category: Page 25

Sep 23, 2023

Brazilian researchers develop method of purifying water contaminated by glyphosate

Posted by in categories: chemistry, economics

Researchers at São Paulo State University (UNESP) in Brazil have developed a strategy for removing glyphosate, one of the world’s most frequently used herbicides, from water. Inspired by the concept of the circular economy, the technique is based on sugarcane bagasse, a waste material produced by sugar and ethanol plants.

“Isolated and chemically functionalized sugarcane bagasse fibers can be used as adsorbent material. Glyphosate adheres to its surface and is removed as a water contaminant by filtration, decantation or centrifugation,” Maria Vitória Guimarães Leal, told Agência FAPESP.

She is the first author of an article on the research published in the journal Pure and Applied Chemistry. Adsorption is a process whereby molecules dispersed in a liquid or gaseous medium adhere to a solid insoluble surface, which is typically porous.

Sep 22, 2023

SLAC fires up the world’s most powerful X-ray laser: LCLS-II ushers in a new era of science

Posted by in categories: biological, chemistry, computing, quantum physics, science, sustainability

The newly upgraded Linac Coherent Light Source (LCLS) X-ray free-electron laser (XFEL) at the Department of Energy’s SLAC National Accelerator Laboratory successfully produced its first X-rays, and researchers around the world are already lined up to kick off an ambitious science program.

The upgrade, called LCLS-II, creates unparalleled capabilities that will usher in a new era in research with X-rays.

Scientists will be able to examine the details of quantum materials with unprecedented resolution to drive new forms of computing and communications; reveal unpredictable and fleeting chemical events to teach us how to create more sustainable industries and ; study how carry out life’s functions to develop new types of pharmaceuticals; and study the world on the fastest timescales to open up entirely new fields of scientific investigation.

Sep 22, 2023

Violating the Universal Kasha’s Rule — Scientists Uncover Secrets of a Mysterious Blue Molecule

Posted by in categories: chemistry, energy

Scientists from IOCB Prague are the first to describe the causes of the behavior of one of the fundamental aromatic molecules, azulene. This molecule has captivated the scientific community not just with its distinct blue hue, but also with its unique properties.

Their current undertaking will influence the foundations of organic chemistry in the years to come and in practice will help harness the maximum potential of captured light energy. Their findings were recently published in the Journal of the American Chemical Society (JACS).

Azulene has piqued the curiosity of chemists for many years. The question of why it is blue, despite there being no obvious reason for this, was answered almost fifty years ago by a scientist of global importance, who, coincidentally, had close ties with IOCB Prague, Prof. Josef Michl.

Sep 22, 2023

World’s most powerful X-ray laser will ‘film’ chemical reactions in unprecedented detail

Posted by in category: chemistry

Upgraded laser in California will produce one million X-ray pulses per second to study ultrafast processes at the atomic level.

Sep 22, 2023

Israeli Researchers Develop Method for Safely Detecting Landmines — Using Bacteria

Posted by in categories: chemistry, innovation

By John Jeffay, ISRAEL21c

Researchers in Israel have announced a breakthrough in safely detecting landmines – using bacteria.

They’ve developed tiny pellet-sized biosensors based on E. coli. The biosensors are dispersed over the target area, where they sniff out the chemical signature of buried explosives and become luminescent.

Sep 21, 2023

Scientists Discover That the Genes for Learning and Memory Are 650 Million Years Old

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

A team of scientists led by researchers from the University of Leicester has determined that genes responsible for learning, memory, aggression, and other complex behaviors emerged approximately 650 million years ago.

The research spearheaded by Dr. Roberto Feuda, of the Neurogenetic group within the Department of Genetics and Genome Biology, in collaboration with colleagues from the University of Leicester and the University of Fribourg (Switzerland), has recently been published in the journal Nature Communications.

<em>Nature Communications</em> is a peer-reviewed, open-access, multidisciplinary, scientific journal published by Nature Portfolio. It covers the natural sciences, including physics, biology, chemistry, medicine, and earth sciences. It began publishing in 2010 and has editorial offices in London, Berlin, New York City, and Shanghai.

Sep 21, 2023

New self-cleaning membranes developed by researchers dramatically improve efficiency of desalination technologies

Posted by in categories: chemistry, engineering

A team of NYU Abu Dhabi (NYUAD) researchers has developed a new kind of self-cleaning, hybrid membrane that provides a solution that overcomes significant challenges that have, until now, limited desalination technologies.

The most energy-efficient desalination technologies are based on membrane desalination. However, the membranes used for desalination are prone to fouling, the accumulation of scale that results in decreased membrane performance, shorter lifespan, and the need for chemical cleaning, which has unknown environmental consequences.

Researchers at NYUAD’s Smart Materials Lab and the Center for Smart Engineering Materials, led by Professor Panče Naumov and Research Scientist Ejaz Ahmed, together with their collaborators from the Institute for Membrane Technology in Italy, created a unique hybrid membrane by utilizing stimuli-responsive materials, thermosalient organic crystals, embedded in polymers. The thermosalient crystals are a new class of dynamic materials that are capable of sudden expansion or motion upon heating or cooling.

Sep 20, 2023

More Informative Together Than Apart

Posted by in category: chemistry

The concurrent analysis of two measurements of a biochemical signaling network can provide more information than two separate probes of the datasets.

Sep 20, 2023

Self-Repelling Species Still Self-Organize

Posted by in categories: bioengineering, biological, chemistry, particle physics

Many biological processes depend on chemical reactions that are localized in space and time and therefore require catalytic components that self-organize. The collective behavior of these active particles depends on their chemotactic movement—how they sense and respond to chemical gradients in the environment. Mixtures of such active catalysts generate complex reaction networks, and the process by which self-organization emerges in these networks presents a puzzle. Jaime Agudo-Canalejo of the Max Planck Institute for Dynamics and Self-Organization, Germany, and his colleagues now show that the phenomenon of self-organization depends strongly on the network topology [1]. The finding provides new insights for understanding microbiological systems and for engineering synthetic catalytic colloids.

In a biological metabolic network, catalysts convert substrates into products. The product of one catalyst species acts as the substrate for another species—and so on. Agudo-Canalejo and his team modeled a three-species system. First, building on a well-established continuum theory for catalytically active species that diffuse along chemical gradients, they showed that systems where each species responds chemotactically only to its own substrate cannot self-organize unless one species is self-attracting. Next, they developed a model that allowed species to respond to both their substrates and their products. Pair interactions between different species in this more complex model drove an instability that spread throughout the three-species system, causing the catalysts to clump together. Surprisingly, this self-organization process occurred even among particles that were individually self-repelling.

The researchers say that their discovery of the importance of network topology—which catalyst species affect and are affected by which substrates and products—could open new directions in studies of active matter, informing both origin-of-life research and the design of shape-shifting functional structures.

Sep 20, 2023

First Light for a Next-Generation Light Source

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

X-ray free-electron lasers (XFELs) first came into existence two decades ago. They have since enabled pioneering experiments that “see” both the ultrafast and the ultrasmall. Existing devices typically generate short and intense x-ray pulses at a rate of around 100 x-ray pulses per second. But one of these facilities, the Linac Coherent Light Source (LCLS) at the SLAC National Accelerator Laboratory in California, is set to eclipse this pulse rate. The LCLS Collaboration has now announced “first light” for its upgraded machine, LCLS-II. When it is fully up and running, LCLS-II is expected to fire one million pulses per second, making it the world’s most powerful x-ray laser.

The LCLS-II upgrade signifies a quantum leap in the machine’s potential for discovery, says Robert Schoenlein, the LCLS’s deputy director for science. Now, rather than “demonstration” experiments on simple, model systems, scientists will be able to explore complex, real-world systems, he adds. For example, experimenters could peer into biological systems at ambient temperatures and physiological conditions, study photochemical systems and catalysts under the conditions in which they operate, and monitor nanoscale fluctuations of the electronic and magnetic correlations thought to govern the behavior of quantum materials.

The XFEL was first proposed in 1992 to tackle the challenge of building an x-ray laser. Conventional laser schemes excite large numbers of atoms into states from which they emit light. But excited states with energies corresponding to x-ray wavelengths are too short-lived to build up a sizeable excited-state population. XFELs instead rely on electrons traveling at relativistic speed through a periodic magnetic array called an undulator. Moving in a bunch, the electrons wiggle through the undulator, emitting x-ray radiation that interacts multiple times with the bunch and becomes amplified. The result is a bright x-ray beam with laser coherence.

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