Predicting how proteins bind to other molecules could revolutionize biochemistry, drug discovery.
Researchers have engineered nanosized cubes that spontaneously form a two-dimensional checkerboard pattern when dropped on the surface of water. The work, published in Nature Communications (“Self-assembly of nanocrystal checkerboard patterns via non-specific interactions”), presents a simple approach to create complex nanostructures through a technique called self-assembly.
“It’s a cool way to get materials to build themselves,” said study co-senior author Andrea Tao, a professor in the Aiiso Yufeng Li Family Department of Chemical and Nano Engineering at the University of California San Diego. “You don’t have to go into a nanofabrication lab and do all these complex and precise manipulations.”
Each nanocube is composed of a silver crystal with a mixture of hydrophobic (oily) and hydrophilic (water-loving) molecules attached to the surface. When a suspension of these nanocubes is introduced to a water surface, they arrange themselves such that they touch at their corner edges. This arrangement creates an alternating pattern of solid cubes and empty spaces, resulting in a checkerboard pattern.
National University of Singapore (NUS) chemists have developed hexavalent photocatalytic covalent organic frameworks (COFs) which mimic natural photosynthesis for the production of hydrogen peroxide (H 2 O2), an important industrial chemical.
The conventional method of H 2 O2 production involves using anthraquinone as a catalyst to convert air and hydrogen into H 2 O2. However, this process requires substantial energy, costly noble metal catalysts, high-pressure hydrogen gas and hazardous solvents. Artificial photosynthesis of H 2 O2, resembling the natural photosynthesis process with the use of sunlight as an energy source and abundant water and air as feedstocks, presents a sustainable and promising alternative to the conventional anthraquinone process.
However, such an artificial system faces three key challenges: insufficient charge carrier generation and fast charge recombination, which lowers the efficiency; limited number of available catalytic sites, which results in low productivity; and lack of efficient delivery of charges and reactants to the catalytic sites, which causes sluggish reaction kinetics.
For the first time in history, scientists have measured radium’s bonding interactions with oxygen atoms in an organic molecule. Scientists have not measured this bonding before because radium-226 is available only in small amounts and it is highly radioactive (radium is one million times more radioactive than the same mass of uranium), making it challenging to work with.
Scientists refer to this phenomenon as the Great Oxidation Event, or GOE for short. But the initial accumulation of O2 on Earth was not nearly as straightforward as that moniker suggests, according to new research led by a University of Utah geochemist.
This “event” lasted at least 200 million years. And tracking the accumulation of O2 in the oceans has been very difficult until now, said Chadlin Ostrander, an assistant professor in the Department of Geology and Geophysics.
“Emerging data suggest that the initial rise of O2 in Earth’s atmosphere was dynamic, unfolding in fits-and-starts until perhaps 2.2. billion years ago,” said Ostrander, lead author on the study published June 12 in the journal Nature. “Our data validate this hypothesis, even going one step further by extending these dynamics to the ocean.”
Most of the universe is invisible to the human eye. The building blocks of stars are only revealed in wavelengths that are outside of the visible spectrum. Astronomers recently used two very different, and very powerful, telescopes to discover twin disks—and twin parallel jets—erupting from young stars in a multiple star system.
This discovery was unexpected, and unprecedented, given the age, size, and chemical makeup of the stars, disks, and jets. Their location in a known, well-studied part of the universe adds to the thrill.
Observations from the U.S. National Science Foundation’s (NSF) National Radio Astronomy Observatory’s (NRAO) Atacama Large Millimeter/submillimeter Array (ALMA) and NASA’s James Webb Space Telescope’s (JWST) Mid-Infrared Instrument (MIRI) were combined for this research.
Promethium, one of the rarest and most mysterious elements in the periodic table, has finally given up some crucial chemical secrets.
By Mark Peplow & Nature magazine
One of the rarest and most mysterious elements in the periodic table has finally given up some crucial chemical secrets, eight decades after its discovery. Researchers at Oak Ridge National Laboratory in Tennessee have become the first to use radioactive promethium to make a chemical ‘complex’ — a compound in which it is bound to a few surrounding molecules. This feat of synthesis enabled the team to study how the element bonds with other atoms in a solution with water. Published May 22 in Nature the findings fill a long-standing gap in chemistry textbooks, and could eventually lead to better methods for separating promethium from similar elements in nuclear waste, for example.
In relationships, sharing closer spaces naturally deepens the connection as bonds form and strengthen through increasing shared memories. This principle applies not only to human interactions but also to engineering. Recently, an intriguing study was published demonstrating the use of quantum dots to create metasurfaces, enabling two objects to exist in the same space.
Professor Junsuk Rho from the Department of Mechanical Engineering, the Department of Chemical Engineering, and the Department of Electrical Engineering, PhD candidates Minsu Jeong, Byoungsu Ko, and Jaekyung Kim from the Department of Mechanical Engineering, and Chunghwan Jung, a PhD candidate, from the Department of Chemical Engineering at Pohang University of Science and Technology (POSTECH) employed Nanoimprint Lithography (NIL) to fabricate metasurfaces embedded with quantum dots, enhancing their luminescence efficiency. Their research was recently published in Nano Letters (“Printable Light-Emitting Metasurfaces with Enhanced Directional Photoluminescence”).
(Left) Schematic diagram of the fabrication of a luminescence-controlled metasurface using the nanoimprint lithography process. (Right) Experiment evaluating the performance of the metasurface’s luminescence control. (Image: POSTECH)
Scientists think that helium hydride is the universe’s first chemical bond, yet the ion has proven surprisingly difficult to locate.
