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1.
K. Hamaguchi Y. Maeda H. Matsumoto M. Nishiuchi H. Tomida K. Koyama H. Awaki T. G. Tsuru 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2000,450(2-3):360-364
We have developed a CCD calibration system using fluorescent X-ray lines with energies ranging from 1.49 keV (Al K) to 11.2 keV (Se K). The absolute X-ray flux is calibrated by a gas proportional counter, while the emerging spectra are monitored by solid-state silicon detectors. In order to suppress contaminating X-rays in the fluorescence spectra, mechanical collimators were set in the X-ray beam line, high-purity targets for fluorescent lines were used, and band-pass filters were put on the X-ray beam line. As for the purity of the fluorescent X-rays, the typical purity achieved was 98%. 相似文献
2.
Non-invasive surgery techniques and drug delivery system with acoustic characteristics of ultrasound contrast agent have been studied intensively in recent years. Many ultrasound contrast agents are commercially available, and they are usually composed of a microbubble coated by a surfactant or lipid bilayer, i.e., a hollow microsphere. We show that the hollow microsphere with polymer shell can be fabricated just blowing vapor of commonly-used instant adhesive into water as microbubbles. The hollow microspheres are composed of cyanoacrylate, a biocompatible material used for adhesion to human tissue such as skin, blood vessels, and organs. Moreover these are less than 10 μm in diameter, which is smaller than a blood capillary (approximately 10 μm). Therefore, with their stable polymer shells, the hollow microspheres are possible ultrasound contrast agents, and are expected to be generated at low cost on the medical frontline, and not in a pharmaceutical factory. 相似文献
3.
Toshinori Taishi Hideaki IseYu Murao Takayuki OhsawaYuki Tokumoto Yutaka OhnoIchiro Yonenaga 《Microelectronic Engineering》2011,88(4):496-498
Local vibrations of oxygen in Ge crystals grown from a melt fully covered by B2O3 were evaluated by Fourier-transform infrared spectroscopy. Ge single crystals containing oxygen were grown by the Czochralski method under various growth conditions. Oxygen concentrations in the crystals were determined to be in the range between 8.5 × 1015 and 5.5 × 1017 cm−3 from the infrared absorption at 855 cm−1 originating in local vibration of Ge-Oi-Ge quasi-molecules. Absorption peaks relating to GeOx, SiOx and Si-Oi-Si were not detected in the as-grown crystals. The calibration coefficient for determining oxygen concentration in Ge crystals from the absorption peak intensity at 1264 cm−1 was estimated to be 1.15 × 1019 cm−2. 相似文献
4.
Tai Cheng Chuanjiang Qin Satoru Watanabe Toshinori Matsushima Chihaya Adachi 《Advanced functional materials》2020,30(24)
Quasi‐2D metal halide perovskite films are promising for efficient light‐emitting diodes (LEDs), because of their efficient radiative recombination and suppressed trap‐assisted quenching compared with pure 3D perovskites. However, because of the multidomain polycrystalline nature of solution‐processed quasi‐2D perovskite films, the composition engineering always impacts the emitting properties with complicated mechanisms. Here, defect passivation and domain distribution of quasi‐2D perovskite films prepared with various precursor compositions are systematically studied. As a result, in perovskite films prepared from stoichiometric quasi‐2D precursor compositions, large organic ammonium cations function well as passivators. In comparison, precursor compositions of simply adding large organic halide salt into a 3D perovskite precursor ensure not only the defect passivation but also the effective formation of quasi‐2D perovskite domains, avoiding unfavorable appearance of low‐order domains. Quasi‐2D perovskite films fabricated with a well‐designed precursor composition achieve a high photoluminescence quantum yield of 95.3% and an external quantum efficiency of 14.7% in LEDs. 相似文献
5.
Rong Xu Jinhui Wang Masakoto Kanezashi Tomohisa Yoshioka Toshinori Tsuru 《American Institute of Chemical Engineers》2013,59(4):1298-1307
Hybrid organosilica membranes were successfully prepared using bis(triethoxysilyl)ethane (BTESE) and applied to reverse osmosis (RO) desalination. The organosilica membrane calcined at 300°C almost completely rejected salts and neutral solutes with low‐molecular‐weight. Increasing the operating pressure led to an increase in water flux and salt rejection, while the flux and rejection decreased as salt concentration increased. The water permeation mechanism differed from the viscous flow mechanism. Observed activation energies for permeation were larger for membranes with a smaller pore size, and were considerably larger than the activation energy for water viscosity. The organosilica membranes exhibited exceptional hydrothermal stability in temperature cycles up to 90°C. The applicability of the generalized solution‐diffusion (SD) model to RO and pervaporation (PV) desalination processes were examined, and the quantitative differences in water permeance were accurately predicted by the application of generalized transport equations. © 2012 American Institute of Chemical Engineers AIChE J, 59: 1298–1307, 2013 相似文献
6.
Poly(L-lactic acid) (PLLA) microfibers were obtained by a carbon dioxide (CO2) laser-thinning method. A laser-thinning apparatus used to continuously prepare microfibers was developed in our laboratory; it consisted of spools supplying and winding the fibers, a continuous-wave CO2-laser emitter, a system supplying the fibers, and a traverse. The laser-thinning apparatus produced PLLA microfibers in the range of 100-800 m min−1. The diameter of the microfibers decreased as the winding speed increased, and the birefringence increased as the winding speed increased. When microfibers, obtained through the laser irradiation (at a laser power of 8.0 W cm−2) of the original fiber supplied at 0.4 m min−1, were wound at 800 m min−1, they had a diameter of 1.37 μm and a birefringence of 24.1×10−3. The draw ratio calculated from the supplying and winding speeds was 2000×. The degree of crystal orientation increased with increasing the winding speed. Scanning electron microscopy showed that the microfibers obtained with the laser-thinning apparatus had smooth surfaces not roughened by laser ablation that were uniform in diameter. The PLLA microfiber, which was obtained under an optimum condition, had a Young's modulus of 5.8 GPa and tensile strength of 0.75 GPa. 相似文献
7.
Toshinori Nakagawa Qinchang Zhu Hiroya Ishikawa Koichiro Ohnuki Kenichi Kakino Naoya Horiuchi 《木材化学与工艺学杂志》2016,36(1):42-55
This article presents multiple potential uses of the Yakushima native cedar (Cryptomeria japonica), known in Japan as the Yaku-sugi tree. The Yaku-sugi was divided into four parts: leaves, branches with leaves, branches, and stems. We obtained the essential oil, hydrosol, distillation residue, and distillation wastewater from the trees. Essential oil and hydrosol were determined to be volatile organic compounds. All samples were screened for the following bioactivities: antioxidative, antibacterial, and anti-melanogenesis activities. Freeze-dried distillation residue was tested to assess whether it had a deodorizing effect. The main component of the leaf essential oil was found to be monoterpenes. In contrast, the stem essential oil mainly contained sesquiterpenes. In terms of bioactivities, the leaf essential oil showed antibacterial activity and the stem essential oil showed anti-melanogenesis activity. Distillation residue and wastewater showed many activities, including antioxidant, antibacterial, and anti-melanogenesis activities. Moreover, the residue had a deodorizing effect against ammonia. 相似文献
8.
Seiichi Deguchi Toshinori Takeichi Shoji Shimasaki Muneaki Ogawa Norifumi Isu 《American Institute of Chemical Engineers》2011,57(8):2237-2243
To enhance photocatalytic water splitting, various oxidizing sacrifice agents (OSA) have been added to the system in order to scavenge the coproduced O2, and, thus, to hinder the reverse reactions. In the aim of achieving carbon‐neutral photocatalytic water splitting, nonfood hydrocarbons of castor‐ and jojoba‐oils were evaluated as OSA. Moreover, various surfactants were tested as emulsifiers for W/O binary solution for promoting photocatalytic water splitting rate. Among the OSA used, the castor‐oil was found to be more suitable candidate compared to jojoba‐oil, which was attributed to its smaller carbon chain numbers of mainly 18. Without surfactants, around 20 vol %‐castor‐oil aqueous binary solution with TiO2/Pt(0.10 wt %) provided the highest water splitting rate of about 30 mL‐H2/(m2·h). Among tested surfactants, liquid‐detergent was the best due to its optical transparency. 40 vol %‐ or 60 vol %‐castor‐oil emulsion with a drop of liquid‐detergent resulted in a water splitting rate of 125 mL‐H2/(m2·h), which was four times greater that the aforementioned highest value. © 2010 American Institute of Chemical Engineers AIChE J, 2011 相似文献
9.
Hye Ryeon Lee Masakoto Kanezashi Yoshihiro Shimomura Tomohisa Yoshioka Toshinori Tsuru 《American Institute of Chemical Engineers》2011,57(10):2755-2765
Organic/inorganic hybrid silica membranes were prepared from 1,1,3,3‐tetraethoxy‐1,3‐dimethyl disiloxane (TEDMDS) by the sol‐gel technique with firing at 300–550°C in N2. TEDMDS‐derived silica membranes showed high H2 permeance (0.3–1.1 × 10?6 mol m?2 s?1 Pa?1) with low H2/N2 (~10) and high H2/SF6 (~1200) perm‐selectivity, confirming successful tuning of micropore sizes larger than TEOS‐derived silica membranes. TEDMDS‐derived silica membranes prepared at 550°C in N2 increased gas permeances as well as pore sizes after air exposure at 450°C. TEDMDS had an advantage in tuning pore size by the “template” and “spacer” techniques, due to the pyrolysis of methyl groups in air and Si? O? Si bonding, respectively. For pore size evaluation of microporous membranes, normalized Knudsen‐based permeance, which was proposed based on the gas translation model and verified with permeance of zeolite membranes, reveals that pore sizes of TEDMDS membranes were successfully tuned in the range of 0.6–1.0 nm. © 2011 American Institute of Chemical Engineers AIChE J, 2011 相似文献
10.
Meng Guo Masakoto Kanezashi Hiroki Nagasawa Liang Yu Kazuki Yamamoto Takahiro Gunji Toshinori Tsuru 《American Institute of Chemical Engineers》2020,66(4):e16850
Fine-tuned, molecular-composite, organosilica membranes were fabricated via the co-condensation of organosilica precursors bis(triethoxysilyl)acetylene (BTESA) and bis(triethoxysilyl)benzene (BTESB). Fourier transform infrared and UV–vis spectra confirmed the co-condensation behaviors of BTESA and BTESB. The evolution of the network structure indicated that the incorporated BTESB decreased the membrane pore size, which was determined by a modified gas translation model according to the steric effect of the phenyl groups. The incorporation of BTESB to BTESA finely tuned the membrane structure and endowed the resultant composite membrane with improved separation properties. The BTESAB 9:1 membrane (molar ratio of BTESA/BTESB was 9:1) exhibited high C3H6 permeance at 4.5 × 10−8 mol m−2 s−1 Pa−1 and a C3H6/C3H8 permeance ratio of 33 at 50°C. One of the most important developments of this study involved clearly defining the relationship between membrane pore size and C3H6/C3H8 separation performance for organosilica membranes in single and binary separation systems. 相似文献