Phys.org August 30, 2019 Conventional defrosting melts all the ice or frost from the top layer. Researchers at the University of Illinois proposed delivering a pulse of very high current where the ice and the surface meet to create a layer of water. To ensure the pulse reaches the intended space rather than melting the exposed ice, they applied a thin coating of indium tin oxide to the surface of the material. They validated the concept in an experimental model which showed that <1% of the energy and <0.01% of the defrosting time was needed compared to conventional thermal-based defrosting […]
Category Archives: Materials science
In a Totally Unexpected Finding, Water Has Spontaneously Produced Hydrogen Peroxide
Science Alert September 1, 2019 According to the researchers at Stanford University the spontaneous production of hydrogen peroxide can occur when water is atomised into microdroplets without any chemical reagent, catalyst, applied electric potential, or radiation. Hydrogen peroxide production yield was inversely proportional to microdroplet size. The discovery could lead to new and more environmentally sustainable ways of manufacturing this common chemical and innovative opportunities including green and inexpensive production of hydrogen peroxide, green chemical synthesis, safe cleaning, and food processing…read more. TECHNICAL ARTICLE
Revolutionary way to bend metals could lead to stronger military vehicles
Eurekalert August 12, 2019 Dislocation activity is critical to ductility and the mechanical strength of metals. In general, suppressing dislocation activity leads to brittleness of polycrystalline materials. An international team of researchers (USA – University of Wisconsin, George Mason University, UT Arlington, China) found that bending samarium cobalt caused narrow bands to form inside the crystal lattice, where molecules assumed a freeform “amorphous” configuration instead of the regular, grid-like structure in the rest of the metal. Those amorphous bands allowed the metal to bend. Next, the researchers plan to search for other materials that might also bend in this peculiar […]
Artificial intelligence (AI) designs metamaterials used in the invisibility cloak
EurelAlert July 14, 2019 Researchers in South Korea developed an AI system and taught it to design arbitrary photonic structures and gave additional level of freedom of the design by categorizing types of materials and adding them as a design factor, which made it possible to design appropriate materials for relevant optical properties. Previous studies required inputs of materials and structural parameters beforehand and adjusting photonic structures afterwards. The current process significantly reduced the time needed to design photonic structures…read more. Open Access TECHNICAL ARTICLE
Perfect quantum portal emerges at exotic interface
Nanowerk June 26, 2019 A team of researchers in the US (University of Maryland, UC Irvine) has observed perfect Andreev reflection in point-contact spectroscopy—a clear signature of Klein tunneling and a manifestation of the underlying ‘relativistic’ physics of a proximity-induced superconducting state in a topological Kondo insulator. The findings shed light on a previously overlooked aspect of topological superconductivity and can serve as the basis for a unique family of spintronic and superconducting devices, the interface transport phenomena of which are completely governed by their helical topological states…read more. TECHNICAL ARTICLE
Scientists Have Found a Way to Prevent Water From Ever Becoming Ice
Science Alert April 12, 2019 There are around 20 different molecular varieties of water– some so esoteric and rare, they may only exist inside computer simulations, or buried within distant planets. The physical confinement of water at the nanoscale can play a major role in controlling its properties. Confinement in the nanometre range can inhibit the arrangement of water molecules into an ice structure, and thereby prevent crystallisation at subzero temperature and create a state of amorphous water. Researchers in Switzerland synthesised a new class of fat molecules that form into a soft biological material called a lipidic mesophase, an […]
Observing a molecule stretch and bend in real-time
Phys.org April 9, 2019 In 2016 an international team of researchers (Spain, Poland, USA – Kansas State University, Germany) achieved the required spatial and temporal resolution to take snapshots of molecular dynamics without missing any events. Now the group has observed the structural bending and stretching of the triatomic molecular compound carbon disulphide, CS2. They reported that the ultrafast modifications in the molecular structure are driven by changes in the electronic structure of the molecule. This effect is key for important triatomic molecules such as CS2, since it can determine specific chemical reactions in the Earth’s atmosphere that could, for […]
A New ‘State’ of Matter Can Be Solid And Liquid at The Same Time
Science Alert April 9, 2019 Applying high pressures and temperatures to potassium creates a state in which most of the element’s atoms form a solid lattice structure. Researches in the UK used powerful computer simulations to observe this behaviour of around 20,000 potassium atoms under extreme conditions. When the pressure and temperature are high enough – around 2 to 4 Gigapascals – the potassium atoms arranged themselves in interlinked chains and lattices. The chemical interactions between the lattice atoms are strong, so they remain an ordered solid when a temperature between 400 and 800 Kelvin is applied. But meanwhile, the […]
The taming of the light screw
Phys.org March 22, 2019 Researchers in Germany performed high-harmonic generation measurements from silicon and quartz to demonstrate that the polarization states of the harmonics are not only determined by crystal symmetries, but can be dynamically controlled, as a consequence of the intertwined interband and intraband electronic dynamics. Using symmetry-dynamics duality they generated coherent circularly polarized harmonics from elliptically polarized pulses. The method is versatile and expected to find important applications in future studies of novel quantum materials such as strongly correlated materials, topological insulators, and magnetic materials… read more. Open Access TECHNICAL ARTICLE
Magnetic graphene switches between insulator and conductor
Phys.org February 1, 2019 By squashig layers of FePS3 together under high pressure (about 10 Gigapascals) an international team of researchers (UK, South Korea, France, Russia) found that it switched between an insulator and conductor. The conductivity could also be tuned by changing the pressure. These materials are characterised by weak mechanical forces between the planes of their crystal structure. Under pressure, the planes are pressed together, gradually and controllable pushing the system from three to two dimensions, and from insulator to metal. Even in two dimensions, the material retained its magnetism. The research opens possibility for producing two-dimensional materials with […]