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41.
Shinya Kato Yasuyoshi Kurokawa Shinsuke Miyajima Yuya Watanabe Akira Yamada Yoshimi Ohta Yusuke Niwa Masaki Hirota 《Nanoscale research letters》2013,8(1):361
To achieve a high-efficiency silicon nanowire (SiNW) solar cell, surface passivation technique is very important because a SiNW array has a large surface area. We successfully prepared by atomic layer deposition (ALD) high-quality aluminum oxide (Al2O3) film for passivation on the whole surface of the SiNW arrays. The minority carrier lifetime of the Al2O3-depositedSiNW arrays with bulk silicon substrate was improved to 27 μs at the optimum annealing condition. To remove the effect of bulk silicon, the effective diffusion length of minority carriers in the SiNW array was estimated by simple equations and a device simulator. As a result, it was revealed that the effective diffusion length in the SiNW arrays increased from 3.25 to 13.5 μm by depositing Al2O3 and post-annealing at 400°C. This improvement of the diffusion length is very important for application to solar cells, and Al2O3 deposited by ALD is a promising passivation material for a structure with high aspect ratio such as SiNW arrays. 相似文献
42.
Glycolipids from edible plant sources were accurately quantified by silica-based, normal-phase high-performance liquid chromatography
using an evaporative light-scattering detector. Five major glycolipid classes (acylated steryl glucoside, steryl glucoside,
ceramide monohexoside, monogalactosyldiacylglycerol, and digalactosyldiacylglycerol) were separated and determined with a
binary gradient system consisting of chloroform and methanol/water (95∶5, vol/vol) without any interference from other lipid
classes and pigments. The described method was applied to 48 edible plants available in Japan including cereals, legumes,
vegetables, and fruits. Examined plant species contained glycolipids in wide concentration ranges, such as 5–645 mg/100 g
tissue. 相似文献
43.
Nobuyuki Gokon Yusuke Osawa Daisuke Nakazawa Tatsuya Kodama 《International Journal of Hydrogen Energy》2009
Ni–Cr–Al metallic foam absorber with high porosity was catalytically activated using a Ru/γ-Al2O3 catalyst, and was subsequently tested with respect to CO2 reforming of methane in a small-scale volumetric receiver-reactor by using a sun-simulator. A chemical storage efficiency of 37% was obtained for a mean light flux of 325 kW m−2. Furthermore, the activity and the stability of the metallic foam absorber were compared with those of a SiC foam absorber activated with the same Ru/γ-Al2O3 catalyst for 50 h of light irradiation, and it was found that the metallic foam absorber has superior catalytic stability in comparison to the SiC form absorber. In addition, unlike ceramic foams such as SiC, metallic foams feature superior plasticity, which prevents the emergence of cracks caused by mechanical or thermal shock. 相似文献
44.
45.
Mihashi Mutsuko; Otsubo Yasunao; Yinjuan Xin; Nagatomi Kaori; Hoshiko Michiko; Ishitake Tatsuya 《Canadian Metallurgical Quarterly》2009,28(1):91
Objective: To investigate strategies for broad mass isolation during outbreaks of infectious diseases. Design: A survey using a self-administered questionnaire was conducted on 300 printing company workers in Beijing, China, which was under mass isolation following the 2003 SARS outbreak, in the 7-8 months after the isolation was lifted. Main Outcome Measures: Individuals with psychological disorders were classified on the basis of scores on the 30-item General Health Questionnaire during the recovery period. Psychological disorders were observed in 49 of 187 respondents (26.2%; 95% CI = 20.2, 32.7). Results: The predicting factor with the highest correlation was income reduction, with an odds ratio of 25.0. Other items obtained were gender, range of activities, eating restrictions, restrictions in going out, disinfection of clothing, and infection control, with odds ratios of 3.2, 5.5, 3.9, 3.2, 0.2, and 0.1, respectively, and the contribution ratio was 87.7%. Conclusion: Securing income is suggested to be important in future strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Mitsutoshi Miyasaka Hiroyuki Hara Hiroki Takao Simon Tam Rob Payne Prem Rajalingham Satoshi Inoue Tatsuya Shimoda 《Journal of the Society for Information Display》2005,13(3):187-191
Abstract— Thin‐film transistors (TFTs) are field‐effect transistors that can be used to create large‐scale‐integrated (LSI) circuits. The combination of high‐performance TFTs and transfer technology of the TFTs has the potential to foster the rise of a new flexible microelectronics industry. This paper discusses the current status of flexible microelectronics, using a TFT fingerprint sensor (FPS) as an example. Technology used in active‐matrix displays can easily be applied to the TFT FPS. TFT technology should not be confined to the display industry; its use should be expanded into the semiconductor industry. With the result presented in this paper, we declare a new era of flexible microelectronics open. 相似文献
47.
Tatsuya Akutsu 《Information Processing Letters》2006,100(3):105-109
We consider a relationship between the unit cost edit distance for two rooted ordered trees and the unit cost edit distance for the corresponding Euler strings. We show that the edit distance between trees is at least half of the edit distance between the Euler strings and is at most 2h+1 times the edit distance between the Euler strings, where h is the minimum height of two trees. The result can be extended for more general cost functions. 相似文献
48.
Miyagawa Y Sato H Okabe T Nishiyama T Miyajima M Sunada H 《Drug development and industrial pharmacy》1999,25(4):429-435
The in vivo performance of wax matrix granules (WMGs) prepared by a twin-screw compounding extruder was evaluated in fasted beagle dogs. In vitro dissolution behavior of the model drug, diclofenac sodium (DS), from WMGs was strongly influenced by pH in a dissolution medium due to its solubility (DS is soluble in pH 6.8 and insoluble in pH 1.2 and 4.0) and was independent of paddle rotation rate (50, 100, and 200 rpm) of the dissolution apparatus. Pharmacokinetics parameters such as mean residence time (MRT) showed a sustained action of WMGs in beagle dogs; however, the transit time of WMGs in the small intestine is found to control total drug absorption. Furthermore, the values of the area under the curve (AUC) of the plasma concentration-time curve and the maximum concentration Cmax significantly decreased with decreases in hydroxypropylcellulose (HPC) content in WMGs. Good correlation between one in vitro dissolution parameter (mean dissolution time, MDT) and two in vivo parameters (AUC12 and MRT) suggested that it would be possible to design WMGs with a desired in vivo performance by controlling HPC content. 相似文献
49.
K Shiokawa H Kasuya M Miyajima M Izawa K Takakura 《Canadian Metallurgical Quarterly》1998,42(1):109-15; discussion 115-6
OBJECTIVE: A drug delivery system using copoly(lactic/glycolic acid) was developed for the intracranial administration of papaverine. A rod-shaped implant prepared by a heat compression method was tested to determine its efficacy in preventing cerebral vasospasm in dogs. METHODS: Sixteen dogs were randomly assigned to one of two groups, i.e., placebo or papaverine. Control angiography was performed, followed by right craniectomy and the induction of subarachnoid hemorrhage by the placement of a clot in the Sylvian fissure. Two pellets, containing either 25 mg of papaverine or no papaverine, were placed in the cistern. In in vitro studies, 56% of the actual papaverine loading was released in the first 4 days and 78% within 8 days. On Day 7, angiography was repeated and the animals were killed. A similar experiment using low-dose pellets containing 5 mg of papaverine, half of which was released within 7 days, was performed with 16 mongrel dogs. RESULTS: There were significant differences between the papaverine- and placebo-treated groups in the reductions of vessel diameters of the internal carotid, middle cerebral, and anterior cerebral arteries on the clot side. The mean concentration of papaverine in the clot was 4.5 x 10(-4) mol/L. The low-dose pellet failed to prevent cerebral vasospasm, although the mean concentration of papaverine in the clot was 2.3 x 10(-5) mol/L. CONCLUSION: A prolonged-release preparation of papaverine that could be implanted intracranially at the time of surgery prevented vasospasm significantly while maintaining an appropriate concentration of papaverine in the cistern. 相似文献
50.
Komukai T. Yamamoto T. Sugawa T. Miyajima Y. 《Quantum Electronics, IEEE Journal of》1995,31(11):1880-1889
A 1.064-μm band upconversion pumped Tm3+-doped fluoride fiber amplifier and a laser both operating at 1.47 μm are investigated in detail. The two devices are based on the 3F 4→3H4 transition in a trivalent thulium ion, which is a self-terminating system. When pumped at 1.064 μm, the amplifier has a gain of over 10 dB from 1.44 to 1.51 μm and a low-noise characteristic. Also, the fiber laser generates a high-output power of over 100 mW with a slope efficiency of 59% at around 1.47 μm. These levels of performance will be important for optical communication systems 相似文献