We have deposited AlN thin films, which are highly thermally conductive insulating films, at room temperature independent of substrate and ambient temperature. We also evaluated the practicality of the obtained AlN thin film by measuring its thermal conductivity in the thermoelectric material Bi2Te3 using the 3ω method. AlN thin films were deposited on Bi2Te3 thin films, Ni thin plates and Cu thin plates using pressure gradient sputtering. As a result, an optimum insulating film with a thickness of about 800 nm was obtained after 2 h of deposition at a distance of 10 cm between the target and the sample. The thermal conductivity of Bi2Te3 was obtained to be 0.56±0.05 W/(m･K) by using the AlN thin film in the thermal conductivity measurement by the 3ω method. The thermal conductivity of Bi2Te3 measured using polyimide, which was conventionally used in the 3ω method, was 0.52±0.25 W/(m･K), which means that the measurement error was successfully reduced significantly. The above results indicate that this film is useful as a highly thermally conductive insulating thin film.
This paper focuses on the improvement methods of leaf physiological impediments caused by caffeine. According to previous research, water extract from coffee grounds can promote the growth of Japanese mustard. Nevertheless, some other physiological impediments occurred in the leaves, which are caused by caffeine. The objective of this study concentrated on ameliorating the physiological impediments of leaves. The effects of caffeinated yeast fermentation broth on the growth and leaf status of Japanese mustard were systematically investigated. The results demonstrated that yeast fermentation could reduce the content of caffeine. Yeast fermented caffeine solution promoted the growth of Japanese mustard. In addition, caffeine fermented by yeast could significantly improve physiological disorders such as leaf etiolation and chlorosis. The reason of this phenomenon is the breakdown of caffeine by yeast, as well as the fertilizer effects of yeast itself. Therefore, the method may help ameliorate the caffeine-induced physiological impediments of Japanese mustard.
As the hydrogen society progresses, Fuel Cell Vehicles (FCVs) are rapidly becoming more widespread. Metal hydrogen permeable membranes, which are the essential parts of the hydrogen fuels for polymer electrolyte fuel cells (PEFCs), require an alternative material to palladium from a cost point of view. Austenitic stainless steel, which is low cost, corrosion resistant, and easy to prepare for manufacture, has been considered unsuitable as a hydrogen permeable membrane because its passive film inhibits hydrogen permeation. However, destabilization of the surface oxide film and thin processing can be expected to improve its permeability. In this work, 18mass%Cr-8mass%Ni-2mass%Mo-Low Carbon (0.02mass%) stainless steel alloy (SUS316L) foils were irradiated with electron beam (EB) in a nitrogen atmosphere to investigate the effect of EB treatment on hydrogen permeability. The diffusion coefficient of hydrogen in the passive layer on the surface of stainless steel irradiated at 250 kV and 600 kGy was calculated to be promoted about 8 times compared to the untreated one, by applying Schmitz's multilayer hydrogen diffusion permeation model. Based on the results obtained, partial destabilization of the surface oxide film by irradiation treatment is suggested.
Measurement of volatile organic compounds (VOCs) contained in exhaled air and skin gas would be effective for the noninvasive assessment of metabolism and disease screening. Furthermore, simultaneous measurement of multiple VOCs that were generated at the same metabolic pathway is important for understanding metabolic functions, e.g., evaluation of alcohol metabolism possible by measuring ethanol (EtOH) and acetaldehyde (AcH). Here we report a parallel gas-imaging system of breath EtOH and AcH using the oxidation and reduction reactions of nicotinamide adenine dinucleotide (NADH)-dependent alcohol dehydrogenase (ADH). This system allowed gas-imaging of two VOCs by using a high-sensitivity camera to capture a fluorescence of NADH (excitation:340 nm, fluorescence: 490 nm), which increased by the oxidation of EtOH and decreased by the reduction of AcH catalyzed by the ADH in the enzyme immobilized meshes placed parallel in front of the camera. In addition, the system was possible to quantify the EtOH and AcH in exhaled air after alcohol consumption based on the image analysis technique.