Phys.org September 13, 2022 The direct electrolysis of seawater is greatly inhibited by the oxidation of Cl– to free chlorine, an undesirable, corrosive byproduct. To suppress the interference of Cl– and any other ion, researchers in Canada developed a freestanding, electrically conducting, 3D macroporous reduced graphene oxide (rGO) scaffold with cobalt oxide particles selectively deposited on the internal walls of its closed pores. The pore walls act as membranes composed of stacked rGO flakes; the nanochannels between rGO layers are permeable to water and gases while preventing the diffusion of dissolved ions such as Cl–. Due to this, the catalytic […]
Researchers generate fusion at 100 million Kelvin for 20 seconds
Phys.org September 8, 2022 An international team of researchers (South Korea, Princeton University, Columbia University) generated plasmas at a temperature of 100 million kelvin lasting up to 20 seconds without plasma edge instabilities or impurity accumulation. They used edge-transport barrier which shapes the plasma in a way that prevents it from escaping, and an internal transport barrier that works by creating an area of high pressure near the center of the plasma to keep it under control. According to the researchers use of the internal transport barrier resulted in much denser plasma than the other approach. A higher density made it easier […]
Researchers help reveal a ‘blueprint’ for photosynthesis
Science Daily September 9, 2022 The cyanobacterial antenna structures, which are called phycobilisomes, are complex collections of pigments and proteins, which assemble into relatively massive complexes. Researchers have been unable to get the high-resolution images of intact antennae needed to understand how they capture and conduct light energy. An international team of researchers (USA – Michigan State University, Lawrence Berkeley National Laboratory, UC Berkeley, Czech Republic) documented several notable results, including finding a new phycobilisome protein, observing two new ways that the phycobilisome orients its light-capturing rods that hadn’t been resolved before, and the structure of the antenna is available […]
Researchers suggest novel way to generate a light source made from entangled photons
Phys.org September 9, 2022 Researchers at Purdue University have proposed the generation of attosecond entangled biphotons in the extreme-ultraviolet regime by two-photon decay of a metastable atomic state as a source like spontaneous parametric down-conversion photons. The 1s2s1S0 metastable state in helium decays to the ground state by the emission of two energy-time entangled photons with a photon bandwidth equal to the total energy spacing of 20.62 eV. This results in a pair correlation time in the attosecond regime making these entangled photons a highly suitable source for attosecond pump-probe experiments. They calculated and used the biphoton generation rate from […]
Study: Four major climate tipping points close to triggering
Phys.org September 11, 2022 Climate tipping points (CTPs) occur when change in large parts of the climate system become self-perpetuating beyond a warming threshold. Triggering CTPs leads to significant, policy-relevant impacts, including substantial sea level rise from collapsing ice sheets, dieback of biodiverse biomes such as the Amazon rainforest or warm-water corals, and carbon release from thawing permafrost. An international team of researchers (Sweden, UK, Germany) provides a comprehensive reassessment of all the nine policy-relevant tipping elements and their CTPs that were originally identified by Lenton et al. (2008). The team updated assessment of the most important climate tipping elements […]
Through the quantum looking glass
Science Daily September 12, 2022 Quantum state engineering mainly relies on spontaneous parametric downconversion and four-wave mixing, where one or two pump photons spontaneously decay into a photon pair. Both nonlinear effects require momentum conservation for the participating photons, which strongly limits the versatility of the resulting quantum states. Nonlinear metasurfaces have subwavelength thickness and allow the relaxation of this constraint; when combined with resonances, they greatly expand the possibilities of quantum state engineering. An international team of researchers (Germany, USA -Sandia National Laboratory) generated entangled photons via spontaneous parametric downconversion in semiconductor metasurfaces with high–quality factor, quasi-bound state in […]
Top 10 Science and Technology Inventions for the Week of September 9, 2022
01. Antenna enables advanced satellite communications testing 02. Coupling of electron-hole pairs 03. DARPA Unveils New Program to Recruit Early Career Scientists, Engineers 04. Develop Therapeutics as Countermeasures Against Chemical Threats 05. Researchers devise tunable conducting edge 06. Magnetic skyrmions: Two methods for creating them and guiding their motion 07. A new catalyst to slow down global warming 08. Light accelerates conductivity in nature’s ‘electric grid’ 09. New Prototype Device Harvests Water From The Air to Make Hydrogen Fuel 10. New theory for detection of terahertz electromagnetic waves gives hope for advances in IT and medicine And others… New practical […]
Antenna enables advanced satellite communications testing
MIT News September 6, 2022 Researchers at MIT Lincoln Laboratory have installed a Multi-Band Test Terminal (MBTT) which can rotate 15 degrees per second, completing a single revolution in 24 seconds. At this speed, the MBTT can detect and track satellites in medium and low Earth orbit. The MBTT is designed to be easily reconfigured to support multiple radio frequency (RF) bands used for military and commercial satellite SATCOM systems. Since its installation, it has supported a wide range of tests and experiments involving protected tactical waveform (PTW). It is also supporting international outreach efforts led by Space Systems Command […]
Coupling of electron-hole pairs
Nanowerk September 5, 2022 In two-layered molybdenum disulfide, excitation with light produces two different types of electron-hole pairs: intralayer pairs, in which the electron and hole are localized in the same layer of the material, and interlayer pairs, whose hole and electron are in different layers and are therefore spatially separate from one another. The intralayer pairs interact strongly with light. The interlayer excitons are much dimmer but can be shifted to different energies and therefore allow researchers to adjust the absorbed wavelength. They exhibit very strong, nonlinear interactions with one another which play an essential role in many of […]
DARPA Unveils New Program to Recruit Early Career Scientists, Engineers
DARPA August 31, 2020 A new DARPA effort aims to recruit standout scientists and engineers beginning their careers for a two-year position at the agency. The DARPA Innovation Fellowship Program will select fellows to push the limits of existing technology through rapid exploration and analysis of a high volume of promising new ideas. The Projects will focus on answering high-risk/high-reward ‘what if?’ questions and assessing the impact of further investment on problems of importance to the Department of Defense. The fellowships are a great way for the nation’s future scientific thought leaders to have the opportunity to make extensive connections […]