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Yoko Takeyama Shingo Maruyama Yuji Matsumoto 《Science and Technology of Advanced Materials》2011,12(5)
We developed a compact continuous-wave infrared (CW-IR) laser deposition system for the high-throughput growth of organic single crystals. In this system, two CW-IR lasers are used for the sample heating and thermal evaporation of materials. The CW-IR laser heating is simple and allows good control of the deposition rate and growth temperature, in response to the on/off laser switching. Six samples can be loaded simultaneously in a chamber, which allows one-by-one sequential deposition for high-throughput experiments, without breaking the vacuum. Using this setup, we studied the effect of ionic liquids on the growth of C60 crystals in vacuum. 相似文献
194.
The survey of the relevant literatures shows that there have been many studies for portfolio optimization problems and that the number of studies which have investigated the optimum portfolio using evolutionary computation is quite large. But, almost none of these studies deals with genetic relation algorithm (GRA), where GRA is one of the evolutionary methods with graph structure. This study presents an approach to large-scale portfolio optimization problems using GRA with a new operator, called guided mutation. In order to pick up the most efficient portfolio, GRA considers the correlation coefficient between stock brands as strength, which indicates the relation between nodes in each individual of GRA. Guided mutation generates offspring according to the average value of correlation coefficients in each individual, which means to enhance the exploitation ability of evolution of GRA. A genetic relation algorithm with guided mutation (GRA/G) for the portfolio optimization is proposed in this paper. Genetic network programming (GNP), which was proposed in our previous research, is used to validate the performance of the portfolio generated with GRA/G. The results show that GRA/G approach is successful in portfolio optimization. 相似文献
195.
Takuya Kitaoka Shingo Yokota Martina Opietnik Thomas Rosenau 《Materials science & engineering. C, Materials for biological applications》2011,31(6):1221-1229
Carbohydrate-conjugated gold nanoparticles (GNPs) and gold nanolayers (GNLs), which have recently attracted increasing attention as innovative nano-biomaterials, were successfully synthesized using carbohydrate thiosemicarbazones in an aqueous N-methylmorpholine N-oxide (NMMO) system. This system can dissolve various types of carbohydrates including structural polysaccharides, e.g., cellulose. We observed that oxidative NMMO solvent unexpectedly promoted the immediate reduction of [AuIIICl4]– species to nanosized metallic Au0, that is GNP. One possible mechanism is that the chloride ligand was oxidized to chlorate via the formation of a hypochlorite intermediate. Site-selective S-labeling of sugar reducing ends with thiosemicarbazide may have enabled regulated self-assembly immobilization to the surfaces of GNPs and GNLs. The carbohydrate–gold nanoconjugates possess unique nanoarchitectures and biofunctions for carbohydrate–cell interactions. Novel and simple approaches for the structural design of carbohydrate-decorated GNPs and GNLs in the NMMO system have potential to inspire a new phase in glyco-biomaterials engineering. 相似文献
196.
Phase and Formation/Dissolution of Precipitates in Biomedical Co-Cr-Mo Alloys with Nitrogen Addition
Shingo Mineta Alfirano Shigenobu Namba Takashi Yoneda Kyosuke Ueda Takayuki Narushima 《Metallurgical and Materials Transactions A》2013,44(1):494-503
The precipitates in as-cast and heat-treated biomedical Co-28Cr-6Mo-(0 to 0.35)C-(0.15 to 0.25)N alloys (mass pct) were investigated. Heat treatment was carried out at temperatures of 1473?K to 1573?K (1200???C to 1300???C) for holding periods of 0 to 43.2?ks. In the as-cast and heat-treated Co-Cr-Mo-N alloys, no precipitates were detected; nitrogen effectively inhibited the formation of the ??-phase and stabilized the face-centered cubic (fcc) metallic ??-phase. The precipitates observed in the as-cast and heat-treated Co-Cr-Mo-C-N alloys were of the M23X6 type, M2X type, ??-phase (M2T3X type with a ??-Mn structure), and ??-phase (M6X-M12X type). Complete precipitate dissolution was detected in the alloys with carbon contents of less than 0.3 mass pct regardless of the nitrogen content. The main precipitates were of the M2X and M23X6 types after heat treatment for 1.8 to 43.2?ks. The ??-phase precipitate was detected in the early stage of heat treatment at high temperatures. The formation of the M2X-type precipitate was enhanced by the addition of nitrogen, although the constitution of the precipitates depended on the balance between the nitrogen and carbon contents and the heat-treatment conditions. 相似文献
197.
This study deals with an economic analysis of structural systems using a reliability-based design method. In this paper, a new expected total cost concept, which includes initial cost, cost of reliability test, annual maintenance cost, penalty cost for designer's faults and losses by structural failure is proposed. In the proposed formulation, the minimum expected total cost during the life duration with the capital rate of interest and rate of price fluctuations could be evaluated by calculating the present currency and annual prediction procedure. 相似文献
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Kaichi Fujiyoshi Hisanori Yokoyama Feng Ren Shingo Ishida 《Journal of the American Ceramic Society》1993,76(4):981-986
Physicochemical states of vanadium in V-doped SnO2 were studied to clarify the origin of the color of vanadium-tin yellow pigment and its color instability when fired with glaze material. Precision measurements of lattice parameters of V-doped SnO2 revealed that vanadium was dissolved as V4+ and its solubility limit was 0.9 wt% as V2 O5 . It was found that the color of vanadium–tin yellow was produced by two types of undissolved vanadium on SnO2 grains. One is poorly crystallized vandium oxide (v), (V2 O5 )', having a yellow color, and the other is orange-colored crystalline V2 O5 . The structure of (V2 O5 )' was discussed in connection with its color. 相似文献