Phys.org August 14, 2018 Researchers in the UK have developed a way to synthesize large libraries of polymers to make screening for antimicrobial activity faster, and without the need to use sealed vials. By using multiple ‘building blocks’ in their polymers, new antimicrobials were identified – some of which appear to inhibit bacteria growth, contrary to predictions. They found that the best materials do not seem to break apart the bacteria as we predicted, but rather inhibit their growth. The benefit of the method is that it allows screening of hundreds of different structures, enabling the researchers to ‘go fishing’ […]
Tag Archives: Materials science
New materials undergo solid-liquid phase transitions at room temperature
Phys.org July 26, 2018 A team of researchers in the US (University of Colorado, Boulder, NIST) designed two new polymers, one which starts as a solid and can be converted into liquid, and the other which starts as a liquid and can be converted into a solid. The solid and liquid polymers both switch phase when irradiated by UV light with a 365-nm wavelength for about five minutes. However, the light affects the two materials differently. Using light instead of temperature or pressure to control the phase changes makes it possible to exert exquisite spatial control over these phase changes, […]
Researchers charge quest to end ‘voltage fade’
Nanowerk July 23, 2018 An international team of researchers (USA – Cornell University, UC San Diego, Argonne National Laboratory, industry, China, Germany) identified nanoscale defects or “dislocations” in Lithium-rich NMC cathode materials as they charged batteries at a range of voltages going up to 4.4 volts. They demonstrated that heat treating the cathode materials eliminated most of the defects and restored the original voltage showing that voltage fade had been reversed. According to the researchers while heat treating is not scalable, the physics and materials science-based approach to characterizing and then addressing the nanoscale defects offers promise for finding new […]
Heat-conducting crystals could help computer chips keep their cool
Science Daily July 5, 2018 A team of researchers in the US (UT Dallas, University of Illinois, University of Houston) has found high thermal conductivity of 1000 ± 90 W/m/K at room temperature in cubic boron arsenide grown through modified chemical vapor transport technique. The thermal conductivity is a factor of 3 higher than that of silicon carbide and surpassed only by diamond and the basal plane value of graphite. Boron arsenide could be a potential revolutionary thermal management material… read more. TECHNICAL ARTICLE
Manipulating single atoms with an electron beam
Eurekalert July 9, 2018 An international team of researchers (Austria, Norway, Belgium) used the advanced electron microscope to move single silicon atoms in graphene with atomic precision. They have taken the first steps towards automation by detecting the jumps in real time. The new results also improve theoretical models of the process by including simulations. In total, the researchers recorded nearly 300 controlled jumps. Silicon impurity could be moved back and forth between two neighboring lattice sites separated by one tenth-billionth of a meter, like flipping an atomic-sized switch. In principle, this could be used to store one bit of […]
A step closer to single-atom data storage
Phys.org July 10, 2018 Researchers in France found that the holmium atoms could retain record-breaking coercivity in a magnetic field exceeding 8 Tesla. Only at around 45K, the magnets began to spontaneously align themselves to the applied magnetic field. This showed that they can withstand relatively high temperature perturbations and might point to the way forward for running single-atom magnets at more commercially viable temperatures. Each atom can store a single bit of data that can be written and read using quantum mechanics. Such devices promise enormous data capacities… read more. Open Access TECHNICAL ARTICLE
New coatings make natural fabrics waterproof
Science Daily June 29, 2018 Conventional water-repellent coatings have been shown to persist in the environment and accumulate in our bodies. Researchers at MIT have developed a process that allows for iCVD deposition of durable, conformal short fluorinated polymers stabilized with a crosslinking agent resulting in high hydrophobicity, low liquid adhesion while maintaining initial substrate breathability. To further enhance the dynamic water repellency performance, the chemical treatment is combined with physical texturing making this combined approach a suitable candidate to meet the industrial needs. The process works on different kinds of materials including cotton, nylon, linen and paper, opening a […]
Electrospun sodium titanate speeds up the purification of nuclear waste water
Eurekalert June 27, 2018 Electrospun ion exchange fibres provide highly efficient and sustainable material for separation of trace pollutants, such as radionuclides and heavy metals. Researchers in Finland developed a process for electrospinning sodium titanate fibres and tested its ion exchange kinetics measurements. They found that by exploiting electrospun inorganic sub-micron fibres the ion exchanger mass required for a given capacity can be decreased significantly. With the help of this new method, waste water can be treated faster than before, and the environmentally positive aspect is that the process leaves less solid radio-active waste… read more. TECHNICAL ARTICLE
New carbon could signal step-change for the world’s most popular batteries
Phys.org June 25, 2018 An international team of researchers (China, India, UK, France) used ‘Eglinton homocoupling’ involving removing silicon from carbon-silicon groups to produce carbon to carbon links resulting in OSPC-1, an amorphous, very stable and highly conductive anode material for lithium-ion batteries. It does not form dendrites, able to store lithium ions at more than double the rate as graphite with high charging speeds and longer-lasting than graphite. They found no signs of deterioration after over 100 charging and discharging cycles. The method used by the team has the potential to be extended to other 3-D carbon materials… read […]
Scientists predict a new superhard material with unique properties
Phys.org June 14, 2018 An international team of researchers (Russia, Armenia, China) predicted new tungsten borides, some of which are promising hard materials that are expected to be stable in a wide range of conditions, according to the computed composition–temperature phase diagram. The new boron-rich compound WB5 is predicted to be superhard, with a Vickers hardness of 45 GPa, possess high fracture toughness of ∼4 MPa·m0.5, and thermodynamically stable in a wide range of temperatures at ambient pressure, and remains a high-performance material even at very high temperatures. Superhard substances have a broad scope of application in well drilling, machine […]