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排序方式: 共有1231条查询结果,搜索用时 15 毫秒
101.
Hitoshi Sai Hiroyuki Fujiwara Michio Kondo 《Solar Energy Materials & Solar Cells》2009,93(6-7):1087-1090
Back surface reflectors (BSRs) with grating structures have been developed to enhance light trapping in thin-film hydrogenated microcrystalline Si (μc-Si:H) solar cells. As a grating structure, a periodic honeycomb-like dimple pattern with a period of ~450 nm has been fabricated on Al substrates by a self-ordering process using anodic oxidation of Al. The clear diffraction effect has been confirmed on the patterned Al from the angle-dependent reflection. From quantum efficiency measurements, we found that the periodically patterned BSR can confine the incident light more effectively than the random textured BSR, especially at longer wavelengths. 相似文献
102.
ABSTRACT The interfacial adsorption of 2-hydroxy-5-nonylbenzo-phenone oxime (LIX65N) at a n-heptane/water interphase was examined under static and vigorously stirred conditions, varying the aqueous pH from 2 to 12. In static systems, the pH and the concentration dependences of the interfacial tension were analysed on the basis of the Gibbs equation. The acid dissociation equilibrium at the interface was evaluated. In vigorously stirred systems, the interfacial adsorption was observed as a reversible, reproducible decrease of the organic phase concentration in response to stirring. A Langmuir isotherm was applicable for the adsorption of neutral LIX65N in acidic condition. The greater adsorption of the anionic form of LIX65N occurring in alkaline condition required an alternative isotherm. 相似文献
103.
Yoshiyuki Sakamoto Hitoshi Kumagai Shinichi Matsunaga 《Journal of Applied Electrochemistry》2013,43(9):967-973
A novel electrochemical ionic liquid membrane reactor capable of separating NO from a mixture of NO and oxygen with high current efficiency at low temperatures was designed and tested. This reactor consists of a combination of an ionic liquid and a thin film of anodised alumina with two platinum electrodes. During operation of the reactor, NO is electrically transported from the cathode side to the anode side. 相似文献
104.
Tomohiro Isogai Kazuhiro Hirooka Tetsuro Tojo Hitoshi Takebayashi Morihiro Saito Minoru Inaba Akimasa Tasaka 《Electrochimica acta》2011,56(12):4425
Metal fluoride added carbon anodes treated by pre-electrolysis were investigated for electrolytic production of nitrogen trifluoride (NF3) in molten NH4F·KF·4HF at 100 °C. The conditions for pre-electrolysis were first optimized using a graphite sheet anode as a model anode. The formation of fluorine-graphite intercalation compounds (fluorine-GICs) with semi-covalent C–F bonds, (CxF)n, on the MgF2 and CaF2 added carbon anode surface was accelerated by pre-electrolysis at potentials less than 4.0 V. Critical current densities (CCD) on the MgF2 added carbon anodes pre-electrolyzed under various conditions were determined, and the highest CCD was 290 mA cm−2 obtained for that pre-electrolyzed at 3.5 V for 500 C cm−2. This anode was successfully used in the electrolysis at 100 mA cm−2 for 290 h and the maximum NF3 current efficiency was 55%. From these results, it was concluded that the metal fluoride added carbon anode treated by pre-electrolysis has a high potential for electrolytic production of NF3 at higher current density. 相似文献
105.
Hitoshi Matsuki Masaki Goto Kaori Tada Nobutake Tamai 《International journal of molecular sciences》2013,14(2):2282-2302
Bilayers formed by phospholipids are frequently used as model biological membranes in various life science studies. A characteristic feature of phospholipid bilayers is to undergo a structural change called a phase transition in response to environmental changes of their surroundings. In this review, we focus our attention on phase transitions of some major phospholipids contained in biological membranes, phosphatidylcholines (PCs), depending on temperature and pressure. Bilayers of dipalmitoylphosphatidylcholine (DPPC), which is the most representative lipid in model membrane studies, will first be explained. Then, the bilayer phase behavior of various kinds of PCs with different molecular structures is revealed from the temperature–pressure phase diagrams, and the difference in phase stability among these PC bilayers is discussed in connection with the molecular structure of the PC molecules. Furthermore, the solvent effect on the phase behavior is also described briefly. 相似文献
106.
A Comparison Between Machine Flexibility and Routing Flexibility 总被引:2,自引:0,他引:2
Hitoshi Tsubone Mitsuyoshi Horikawa 《International Journal of Flexible Manufacturing Systems》1999,11(1):83-101
In this paper, we evaluate two types of flexibility, machine flexibility and routing flexibility, in terms of manufacturing performance in various shop environments. A simulation-based investigation was conducted to analyze the impact of these types of flexibility on the average flow time of parts under various job flow pattern conditions, which characterize the shop nature from a random job shop to a flow shop, operation time variance, setup time, and shop load. The experimental results show how these types of flexibility affect the average flow time of parts and which type is superior under what conditions. Management can obtain better insight and guidelines for determining priorities or the scale, or scope, of various decision items relating to design standardization, process and operations improvement, investment in new equipment and tools, and the like. 相似文献
107.
Hiroaki Ohfuji Takuo Okuchi Shoko Odake Hiroyuki Kagi Hitoshi Sumiya Tetsuo Irifune 《Diamond and Related Materials》2010,19(7-9):1040-1051
Micrometer- to nanometer-scale structures of the cut surfaces of single- and polycrystalline diamonds by a pulsed ultraviolet laser have been thoroughly investigated by scanning and transmission electron microscopy. Within the laser-cut grooves, the processed diamond surfaces are extensively covered with laser-modified debris which consists of complex layered units of graphite with various crystallinities. The units consist of 1) highly oriented graphite, 2) corrugated graphite, and 3) nanocrystalline graphite, which are sequentially located from the surface of the underlying diamond substrate to the center of the grooves. Detailed textural examinations revealed that the highly oriented graphite unit is a product of the initial graphitization of diamond by a solid-state diffusion process, whereas the latter two units are deposition products from the liquid and/or vapor phases of carbon in the later stage. The present study demonstrates that the laser-cutting of diamonds proceeds in a two-step process: 1) extensive graphitization of laser-scanning path and 2) subsequent sublimation of the pre-formed graphite. These processes are basically identical among the three different types of diamonds (single crystal type Ib, single crystal type IIa and nano-polycrystalline aggregate) tested in this study. 相似文献
108.
Hitoshi Kanoh Miyuki Matsumoto Kazuyo Hasegawa Nobuko Kato Seiichi Nishihara 《Engineering Applications of Artificial Intelligence》1997,10(6):531-537
Several approximate algorithms have been reported to solve large constraint-satisfaction problems (CSPs) within a practical time. While those papers discuss techniques to escape from local optima, this paper describes a method that actively performs global searches. The present method improves the rate of search of genetic algorithms by using viral infection instead of mutation. Partial solutions of a CSP are considered to be viruses, and a population of viruses is created, as well as a population of candidate solutions. The search for a solution is conducted by crossover and infection. Infection substitutes the gene of a virus for the locus decided by the virus. Experimental results using randomly generated CSPs prove that the proposed method is faster that usual genetic algorithms at finding a solution when the constraint density of a CSP is low. 相似文献
109.
Bruce A. Julian Hitoshi Suzuki Goce Spasovski Yusuke Suzuki Yasuhiko Tomino Jan Novak 《Proteomics. Clinical applications》2009,3(9):1023-1028
Chronic kidney disease accounts for a significant portion of many national health-care budgets. In this viewpoint, we highlight recent advances in urinary proteomic analyses that potentially may soon enhance the care of afflicted patients. To achieve this goal, cooperation of interdisciplinary teams from around the world will be vital, so as to standardize methodology for preparation urine samples and technical aspects of the analyses, and for better application of results. These collaborative activities will facilitate translational research in kidney diseases. 相似文献
110.
Tiesheng Li Shuji Okada Hirohito Umezawa Hitoshi Kasai Hachiro Nakanishi Satya S. Talwar Tatsumi Kimura Hiro Matsuda 《Polymer Bulletin》2006,57(5):737-746
Summary 1,4-Bis(3-quinolyl)-1,3-butadiyne (DQ) is known to be polymerized in solid state to give the corresponding polydiacetylene.
However, the polymer yield of DQ bulk crystals is low. Thus, we prepared several types of DQ crystals by different procedures
to find the reason for the low polymer yield. We found three modifications of DQ crystals and they were evaluated by spectroscopic
measurements and X-ray diffraction. DQ bulk crystals (Crystal I) and thermally grown DQ crystals on Crystal I (Crystal II)
have the same structure classified to Type A, which gives regular polydiacetylene structure in low polymer yields. DQ crystals
grown on glass plates by sublimation (Crystal III) belong to the second modification of Type B. DQ nanocrystals prepared by
the reprecipitation method (Crystal IV) are Type B, and thermally grown DQ crystals on nanocrystals (Crystal V) are Type C.
Crystals of Types B and C could be polymerized in low yields without showing excitonic absorption of polydiacetylene indicating
irregular polymerization other than 1,4-addition. For crystals of Type A, we found that the 1,4-addition polymerization proceeded
only in near-surface portions of the crystals. It can be plausibly explained that mobile monomers in the near-surface portion
are only able to take part in their polymerization, resulting in low polymer conversion. 相似文献