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排序方式: 共有2188条查询结果,搜索用时 15 毫秒
971.
972.
Yuichiro Tameda Akimichi Taketa Jeremy D. Smith Manobu Tanaka Masaki Fukushima Charles C.H. Jui Kenichi Kadota Fumio Kakimoto Takeshi Matsuda John N. Matthews Shoichi Ogio Hiroyuki Sagawa Nobuyuki Sakurai Tatsunobu Shibata Masahiro Takeda Stanton B. Thomas Hisao Tokuno Yoshiki Tsunesada Shigeharu Udo 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2009,609(2-3):227-234
The Telescope Array Project is an experiment designed to observe Ultra High Energy Cosmic Rays via a “hybrid” detection technique utilizing both fluorescence light detectors (FDs) and scintillator surface particle detectors (SDs). We have installed three FD stations and 507 SDs in the Utah desert, and initiated observations from March 2008. The northern FD station reuses 14 telescopes from the High Resolution Fly's Eye, HiRes-I station. Each of the two southern FD stations contains 12 new telescopes utilizing new FADC electronics. Each telescope is instrumented with a camera composed of 256 PMTs. Since the detectors are composed of many PMTs and each PMT detects fluorescence photons together with the vast amount of night sky background, a sophisticated triggering system is required. In this paper, we describe the trigger electronics of these new FD stations. We also discuss performance of the FDs with this triggering system, in terms of efficiencies and apertures for various detector configurations. 相似文献
973.
We investigated improvement of workability (viscosity), storage stability, and curing ability of thiirane resin for adhesive applications. The viscosity of bisphenol‐F thiirane resin was lower than that of bisphenol‐A thiirane resin, especially at low temperatures, thus improving ease of handling. Addition of diphenyl decyl phosphite improved its storage stability to a level similar to that of bisphenol‐A epoxy resin. The curing of bisphenol‐F thiirane resin increased three times faster by adding 2,4,6‐tris(dimethylaminomethyl)phenol (DMP‐30) as a tertiary amine. In applications of this new thiirane resin as civil and architectural adhesives, a superior curing ability at low temperature was attained. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 2953–2957, 2001 相似文献
974.
Mitsuhiro Arisawa Masahiro Hamada Ikuko Takamiya Masahiko Shimoda Shiro Tsukamoto Yasuhiko Arakawa Atsushi Nishida 《Advanced Synthesis \u0026amp; Catalysis》2006,348(9):1063-1070
We have developed a method for preparing a recyclable and environmentally benign organopalladium catalyst for the Heck reaction supported on sulfur‐terminated gallium arsenide(001). This three‐component catalyst, {Pd}‐S‐GaAs(001), exhibited high stability and activity, furthermore, it tolerated reuse in 10 runs of the Heck reaction (average yield, 97 %) under aerobic conditions. The sulfur layer was very important to stabilize this catalyst. Only trace amounts of Pd were leached from this catalyst to the reaction mixture, as measured by ICP‐mass. The valence of immobilized Pd was zero by XPS spectrometry. 相似文献
975.
Kawahara M Ogo Y Ueda H Nagamune T 《Protein engineering, design & selection : PEDS》2004,17(10):715-719
Structure-based design of antibody/cytokine receptor chimeras has permitted a growth signal transduction in response to non-natural ligands such as fluorescein-conjugated BSA as mimicry of cytokine-cytokine receptor systems. However, while tight on/off regulation is observed in the natural cytokine receptor systems, many chimeras constructed to date showed residual growth-promoting activity in the absence of ligands. Here we tried to reduce the basal growth signal intensity from a chimera by engineering the transmembrane domain (TM) that is thought to be involved in the interchain interaction of natural cytokine receptors. When the retroviral vectors encoding the chimeras with either the wild-type erythropoietin receptor (EpoR) TM or the one bearing two mutations in the leucine zipper motif were transduced to non-strictly interleukin-6-dependent 7TD1 cells, a tight antigen-dependent on/off regulation was attained, also demonstrating the first antigen-mediated genetically modified cell amplification of non-strictly factor-dependent cells. The results clearly indicate that the TM mutation is an effective means to improve the growth response of the antibody/receptor chimera. 相似文献
976.
Sakae Takenaka Hiroshi Matsumori Takafumi Arike Hideki Matsune Masahiro Kishida 《Topics in Catalysis》2009,52(6-7):731-738
Carbon nanotube (CNT)-supported Pt metal nanoparticles were covered with silica layers by hydrolysis of 3-aminopropyl-triethoxysilane (APTES) and/or tetraethoxysilane (TEOS). The hydrolysis of only APTES resulted in a uniform coverage of silica layers on Pt/CNT, but the thickness of the silica layers was very thin (<1 nm). Pt/CNT could also be coated with silica layers of a few nanometers in thickness by hydrolysis of TEOS, but exposed surfaces of CNTs in the sample were frequently observed. In contrast, the successive hydrolysis of APTES and TEOS brought about a uniform coverage of silica layers of a few nanometers in thickness on Pt/CNT. The silica-coated Pt/CNT showed high catalytic activity for electrochemical reactions in aqueous H2SO4 electrolyte, in spite of a uniform coverage of Pt metal with silica layers. In addition, the coverage of Pt/CNT with silica layers improved its durability in electrochemical reactions. 相似文献
977.
Masashi Kotobuki Takafumi Shido Mizuki Tada Hiroyuki Uchida Hisao Yamashita Yasuhiro Iwasawa Masahiro Watanabe 《Catalysis Letters》2005,103(3-4):263-269
We have developed a new Pt–Fe/mordenite (Pt–Fe/M) catalyst which shows remarkably high activity and selectivity for the oxidation of CO in H2-rich gas compared with Pt/M. In the present work, to understand the role and structure of Pt and Fe in the Pt–Fe/M catalyst, the states of metallic components in ion-exchanged, H2 pre-treated and post-PROX (preferential oxidation of CO) samples have been studied by means of XAFS. It was confirmed that Pt forms the metallic clusters after H2 pretreatment or the PROX experiment, whereas a large part of Fe exists as oxides even after the H2 treatment. At post-analysis of the catalysts used for the PROX experiment, an increase in coordination number of Fe–O was observed. Pt clusters in the Pt–Fe(2:1 weight ratio)/M catalyst, which showed the highest PROX performance, were found to have a different electronic structure from the other catalysts. Additionally, preferential CO adsorption onto Pt sites at Pt–Fe/M was clearly demonstrated by infrared spectroscopy analysis in a stream of 1% CO containing H2. Based on these results, the superior PROX mechanism was discussed. 相似文献
978.
Choi Eun-Ju Iwasa Masahiro Han Kwon-Il Kim Wan-Jae Tang Yujiao Han Weon Cheol Kim Eun-Kyung Park Zee-Yong 《Food science and biotechnology》2016,25(4):1087-1093
Food Science and Biotechnology - Here, the effects of heat-killed Enterococcus faecalis EF-2001 (EF-2001) on atopic eczema (AE) were assessed. An AE model was established in vivo by repetitious... 相似文献
979.
980.
Yasuda M Tsugita N Ito K Yamauchi S Glomm WR Tsuji I Asano H 《Environmental science & technology》2011,45(5):1840-1846
NO(X) absorption in water is quite difficult by comparison with other exhausted gas, such as SO(2), CO(2), and NH(3) because of low solubility of NO(X) in water. We have been developed a NO(X) absorption equipment with a glass fiber filter having high porosity and surface area. When feed NO(X) gas concentration was high, high NO(X) removal efficiency was obtained. This was because the surface area per glass fiber filter volume was about 40 to 600 times higher than for common packing materials. For verification test and industrial application, a high concentration of NO(X) gas (206,000 ppm) produced by a metal dissolution process was treated with a series of two absorption experiments. We can attain 97.6% of NO(X) removal efficiency, and HNO(3) concentration in water was concentrated up to 56.3 wt %. Furthermore, ozone addition to gas and usage of ozone saturated water as an absorbent resulted in complete removal of NO(X) in the gas (up to 120 ppm). This result indicated the importance of aqueous phase oxidation of HNO(2), which produces NO in the gas phase. 相似文献