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排序方式: 共有394条查询结果,搜索用时 31 毫秒
111.
We investigated the lasing modes of quasi-stadium laser diodes that have confocal cavity geometries, with stripe electrode contacts formed either along the cavity axis or a diamond-shaped trajectory. It was clearly demonstrated that by using narrow electrode contact patterns of 2 μm width, the lowest-order axial and ring modes were excited selectively. On the other hand, the second-lowest-order axial and ring modes were excited by using broad electrode patterns of 14 μm width. Experimentally obtained far-field patterns for lasers with broad and narrow electrode contact patterns agree very well with the simulation results obtained using an extended Fox-Li mode calculation method. 相似文献
112.
Effect of hydrogen introduction into some metal oxide and nitride thin films was examined. Modification of electrical and optical properties by hydrogen introduction was examined on SnO2, Sn–GeO2, Ge–CdO2, ZnO. Electrical resistance could be reduced in some films without loosing their transparence to the visible light. Hydrogen introduction to Cu3N changed the film an electrical conductor. Films of AlN and TiN were rather insensitive to the hydrogen introduction; the hydrogen effect was only observed when the nitrides contain some imperfection in the compounds. 相似文献
113.
Ken Furusawa Hideharu Sugihara Kiichiro Tsuji Yasunori Mitani 《Electrical Engineering in Japan》2007,158(1):22-35
In Japan the electricity market will open on April 1, 2004. Electric utility, Power Producer and Supplier (PPS), and Load Service Entity (LSE) will join the electricity market. LSEs purchase electricity based on the Market Clearing Price (:MCP) from the electricity market. LSEs supply electricity to the customers that contracted with the LSEs on a certain electricity price, and one to the customers that introduced Energy Storage System (:ES) on a time‐of‐use pricing. It is difficult for LSEs to estimate whether they have any incentive to promote customers to introduce ES or not. This paper evaluates the reduction of LSEs' purchasing cost from the electricity market and other LSEs' purchasing cost by introducing ES to customers. It is clarified which kind of customers has the effect of decreasing LSEs' purchasing cost and how much MCP of the whole power system the demand‐side energy storage systems change. Through numerical examples, this paper evaluates the possibility of giving the cost merit to both customers with energy storage systems and LSE by using real data for a year's worth of MCP. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(1): 22–35, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20447 相似文献
114.
Shoji Nagaoka Haruko Tobata Yasunori Takiguchi Takao Satoh Toshihiko Sakurai Makoto Takafuji Hirotaka Ihara 《应用聚合物科学杂志》2005,97(1):149-157
Chemically modified cellulose microbeads are useful as cosmetic materials. Cellulose microbeads as supports, prepared by a viscose‐phase‐separation method, are monodisperse and spherical. However, cellulose shows only slight hydrophilicity, even though it has three hydroxyl groups per pyranose ring, because cellulose possesses high crystallinity on account of the cellulose II structure derived from hydrogen bonds among the hydroxyl groups. To increase the hygroscopicity of cellulose microbeads, we have carboxylated them with succinic and glutaric anhydrides. Their hygroscopicity increases with the addition of succinoyl and glutaroyl groups. Moreover, we have confirmed the increased hygroscopicity of microbeads with sodium salinization. We have investigated the decomposition of these hydrophilic cellulose microbeads in aqueous buffer solutions and have confirmed that succinoylated cellulose is more readily decomposed than glutaroylated cellulose microbeads in aqueous solutions. On the other hand, to increase the lipophilicity of cellulose microbeads, we have acylated them with acetic and hexanoic anhydrides. Hydrophobizing microbeads with hexanoyl groups provides an affinity to benzene but not to H2O. In contrast, hydrophobizing with acetyl groups provides affinity not only to benzene but also to H2O. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 149–157, 2005 相似文献
115.
116.
The objective of this study was to evaluate the utility of mixtures among oppositely charged dextran derivatives as constituents of a controlled release microsphere. Carboxymethyldextran (CMD) and dextran sulfate (DS) were used as polyanions, and [2-(diethylamino) ethyl] dextran (EA) and [2-hydroxypropyltrimethylammonium] dextran (CDC) as polycations. The microspheres consisting of hydrophilic and hydrophobic polymers were prepared by emulsion-solvent evaporation method. The mixtures, CMD/EA, CMD/CDC, DS/EA, and DS/CDC, were used as hydrophilic polymers, because they can interact with each other to form polyion complexes for the improvement of sustained-release performances. Cellulose acetate butyrate and theophylline were used as a model hydrophobic polymer and a model drug, respectively. The yield of microspheres was excellent (more than 95%). According to observation, by scanning election microscopy (SEM) microspheres were spherical with a rough surface. The in vitro drug release from microspheres was examined in the JP XIV first fluid, pH 1.2, and second fluid, pH 6.8, at 37°C, and 100 rpm. In the DS/CDC system, drug release was depressed by formation of a polyion complex and not affected by pH of dissolution medium. The release rate was modulated by the ratio of hydrophilic and hydrophobic matrix. This particulate system, in which the polyion complex matrix is strengthened by a hydrophobic polymer, is a promising formulation for drug delivery. 相似文献
117.
Eiji Kanda Tsukasa Eguchi Yasunori Hiyoshi Taketo Chino Yasushi Tsuchiya Takahiro Iwashita Tokuro Ozawa Takao Miyazawa Tomotaka Matsumoto 《Journal of the Society for Information Display》2009,17(2):79-85
Abstract— An active‐matrix capacitive sensor for use in AMLCDs as an in‐cell touch screen has been developed. Pixel sensor circuits are embedded in each pixel by using low‐temperature polycrystalline‐silicon (LTPS) TFT technology. It detects a change in the liquid‐crystal capacitance when it is touched. It is thin, light weight, highly sensitive, and detects three or more touch events simultaneously. 相似文献
118.
The synchronous firing of neurons in a pulse-coupled neural network composed of excitatory and inhibitory neurons is analyzed. The neurons are connected by both chemical synapses and electrical synapses among the inhibitory neurons. When electrical synapses are introduced, periodically synchronized firing as well as chaotically synchronized firing is widely observed. Moreover, we find stochastic synchrony where the ensemble-averaged dynamics shows synchronization in the network but each neuron has a low firing rate and the firing of the neurons seems to be stochastic. Stochastic synchrony of chaos corresponding to a chaotic attractor is also found. 相似文献
119.
Etsuo Marui Satoshi Ema Masatoshi Hashimoto Yasunori Wakasawa 《International Journal of Machine Tools and Manufacture》1998,38(10-11)
Effective chatter prevention during cutting operations is achieved by increasing the damping capacity of a cutting tool system. It is well known that damping capacity is generated through (i) micro-slip at the interface between the tool shank and tool post, (ii) slip at the grain boundary within a vibrating body (that is, internal friction), and (iii) friction between the surface of the vibrating body and the surrounding air. Among these three causes of damping capacity, micro-slip at the interface between the tool shank and tool post is the greatest factor affecting the damping capacity of the cutting tool system. In the research investigation, it is shown that the damping capacity of a cutting tool system is improved by friction acting between the inner wall of a rectangular hole made at the overhanging shank of the cutting tool system and the surface of a plate inserted into this rectangular hole. The damping capacity improvement proposed in this paper is realized by a mechanism similar to the inner friction mechanism. 相似文献
120.
Shuichiro Miwa Yasunori Yamamoto Go Chiba 《Journal of Nuclear Science and Technology》2018,55(6):575-598
Research and development in nuclear reactor physics and thermal-hydraulics continue to be vital parts of nuclear science and technology in Japan. The Fukushima accident not only brought tremendous change in public attitudes towards nuclear engineering and technology, but also had huge influence towards the research and development culture of scientific communities in Japan. After the Fukushima accident, thorough accident reviews were completed by independent committees, namely, Tokyo Electric Power Company (TEPCO), the Japanese government, the Diet of Japan, the Rebuild Japan Initiative Foundation, and the Nuclear and Industrial Safety Agency. Reactor physics and thermal-hydraulics divisions of Atomic Energy Society of Japan (AESJ) also issued the roadmaps after the accident. As a result, lessons learned from the accident were made clear, and a number of new research activities were initiated. The present paper reviews ongoing nuclear engineering research activities in Japanese institutes, universities, and corporations, focusing on the areas in reactor physics and thermal-hydraulics since the Fukushima accident to the present date. 相似文献