Science Daily May 13, 2022 Researchers in Japan developed an easy silica–resin coating technique to compensate for paper’s weaknesses, including its lack of water resistance and strength, and proposed its use as an environmentally friendly alternative to plastic. When they dispersed 2 nm anatase TiO2 nanoparticles on the paper’s cellulose fibers it exhibited moderate photocatalytic effects such as methylene blue degradation and antibacterial activity. The porous silica–resin film which has high adsorptive capacity efficiently captured organic pollutants until they decomposed via photocatalytic reactions. As a result, the stable silica–resin–TiO2 composite coating protected paper from the environment for an extended period, […]
Tag Archives: S&T Japan
It takes three to tangle: Long-range quantum entanglement needs three-way interaction
Science Daily 6, 2022 Researchers in Japan provide simple theorems that show what kinds of long-range entanglement can survive at nonzero temperatures. At temperatures above absolute zero, quantum entanglement must contend with thermal jostling of particles, which is detrimental to long-range entanglement persisting at sufficiently high temperatures. Unlike high-temperature phases, however, there are relatively low temperatures in which not all long-range quantum effects are strictly prohibited, and long-range entanglement can survive even at room temperatures. They proved that entanglement between two subsystems has a finite characteristic length scale at arbitrary temperatures regardless of the system details and the spatial dimension. […]
Light-powered microbes are super-producing chemical factories
Phys.org April 11, 2022 Microorganisms that produce useful substances are usually developed by modifying metabolism to convert energy that would normally be used for growth into a resource for synthesizing these target substances. Researchers in Japan used light, an external energy source, to improve production of useful substances without disrupting the microorganisms’ natural metabolism. As a test they introduced a heterologous membrane protein called rhodopsin into Escherichia coli. Rhodopsin is a pump that is activated by light, and the action of the pump leads to the generation of ATP without using the cell’s natural machinery to produce it. This approach […]
Team achieves 30-fold enhancement of thermoelectric performance in polycrystalline tin selenide
Phys.org March 28, 2022 Tin selenide (SnSe) is known to exhibit a record high energy conversion (ZT) in its single crystal form. However, the performance deteriorates in practical polycrystals because of a low electronic conductivity (σ) and a high thermal conductivity (κ). Researchers in Japan enhanced the ZT of polycrystalline SnSe by demonstrating a high σ and a low κ simultaneously by introducing tellurium (Te) ion into the structure of SnSe. The large-size Te ion in Sn(Se1−xTex) forms weak Sn-Te bonds, leading to the high-density formation of hole-donating Sn vacancies and the reduced phonon frequency and enhanced phonon scattering. This […]
Novel quantum sensing possibilities with nonlinear optics of diamonds
Phys.org March 22, 2022 Taking advantage of the properties, especially the harmonic generation of nitrogen vacancy in diamond researchers Japan have presented an efficient and viable way for creating diamond-based nonlinear optical temperature sensing. Using infrared ultrashort pulse laser stimulation, the team found that the harmonic generation decreased with temperature over the range of 20–300°C. The temperature-dependent change was explained by mismatch due to the speed of different colors of light in the diamond. As the atomic lattice heats up, the difference in the index of refraction between the original light and the higher energy light created by harmonic generation […]
High-Energy Interactions Between Light and Matter Described by Advanced New Mathematical Model
SciTech Daily March 15, 2022 High-harmonic generation has several applications, way to create table-top sources of extreme ultraviolet or x-ray light using lasers, and produce ultrashort light pulses, which are useful for imaging extremely rapid processes such as those that occur in atoms. But high-harmonic generation is inherently difficult to model mathematically, and understand fully. An international team of researchers (Japan, USA – University of Chicago) has developed an analytical approach to high-harmonic generation in the non-perturbative regime using mathematical techniques that had not previously been applied to high-harmonic generation. Their approach revealed the microscopic mechanism that converts incoming intense […]
Spinning electricity under the sky
Nanowerk March 8, 2022 In thermoelectric materials the hot side can be easily obtained by excess heat. Since thermoelectric voltage is proportional to the temperature difference between the hot and cold sides, efficient passive cooling to increase the temperature gradient is of critical importance. Researchers in Japan have designed a magnetic hybrid system where radiative cooling occurs at the top, as heat is lost from a material in the form of infrared radiation, while solar radiation is absorbed at the bottom. They demonstrated this concept by using the spin Seebeck effect. The device shows the highest thermoelectric voltage when both […]
Strong, stretchy, self-healing polymers rapidly recover from damage
Phys.org February 28, 2022 Previously researchers in Japan synthesized multiblock copolymers that exhibited excellent elasticity and self-healing by using the two-component copolymerization of non-polar ethylene and polar methoxyaryl-substituted propylenes. Now they have developed a three-component ‘terpolymer’ of ethylene and two different methoxyaryl-functionalized propylenes using a scandium catalyst. The long, soft sections form a highly flexible matrix, within which are hard and crystalline sections that rapidly re-aggregate after the material is cut, thereby self-healing any damage within five minutes to recover 99% of its toughness and 97% of its tensile strength. The material could be stretched to almost 14 times its […]
Towards self-sensing soft robots with electrochemically driven pumps
Science Daily February 8, 2022 Researchers in Japan based the electrochemical dual transducer (ECDT) design on the electrohydrodynamic (EHD) pump they had previously designed. The pump consisted of a symmetrical arrangement of planar electrodes, which allowed easy control of the flow direction by simply changing the voltage. The arrangement enabled an obstruction-free even flow in each direction due to the same strength of the electric field on either side. They evaluated sensing performance in terms of range of detectable flow, rate, sensitivity, response, and relaxation times, and used mathematical modeling to understand the sensing mechanism. The ECDT does not require […]
Scientists weave atomically thin wires into ribbons
Phys.org January 31, 2022 Using tungsten telluride nanowires researchers in Japan created bundles of wires deposited on a flat substrate and exposed to vapors of chalcogens like sulfur, selenium, and tellurium. With a combination of heat and vapor, the initially separate threads in the bundles were successfully woven together into narrow, atomically thin nanoribbons with a characteristic zigzag structure. By tuning the thickness of the original bundles, they could even choose whether these ribbons were oriented parallel to the substrate or perpendicular to it. By tuning the substrate on which the bundles are placed, they could control whether the ribbons […]