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排序方式: 共有389条查询结果,搜索用时 15 毫秒
381.
Satoshi Watanabe Hiroshi Hyodo Hirohisa Taguchi Kohei Soga Yoshifumi Takanashi Mutsuyoshi Matsumoto 《Advanced functional materials》2011,21(22):4264-4269
It is demonstrated that patterned inorganic phosphor films consisting of rare earth ion doped nanoparticles (RE‐NPs) can be fabricated on plastic sheets using calcination‐ and etching‐free photolithography. Green up‐conversion luminescence and near‐infrared (NIR) fluorescence appears from the RE‐NPs that are prepared from Y2O3 doped with 1 mol% Er3+ and 0.85 mol% Yb3+. The diameter of the RE‐NPs is estimated to be about 300 nm using dynamic light scattering. Visible transmittance of the RE‐NP film fabricated by dip‐coating is more than 90%. Patterned RE‐NP films are obtained by dip‐coating the RE‐NPs on patterned photoresist films fabricated by UV exposure through a photomask, followed by selective removal of the photoresist. Optical, fluorescence, scanning electron, atomic force, and Kelvin probe force microscopies are used for the characterization of the patterned RE‐NP films. The present methodology enables fabrication of patterned RE‐NP films, not only on inorganic substrates but also on plastic sheets, with low cost and material consumption. 相似文献
382.
Kazuaki Uehara Tatsuaki Tagami Itaru Miyazaki Norikazu Murata Yoshifumi Takahashi Hiroshi Ohkubo 《Drug development and industrial pharmacy》2015,41(6):953-958
Context: X-ray inspection equipment is widely used to detect missing materials and defective goods in opaque containers. Its application has been expanded to the pharmaceutical industry to detect the presence of drug tablets in aluminum foil press-through packaging. However, the effect of X-rays on the pharmaceutical quality of drug tablets is not well known.Objective: In this study, the effect of X-rays on the pharmaceutical quality of drug tablets was investigated.Methods: Exposure of acetaminophen, loxoprofen and mefenamic acid tablets to X-ray doses of 0.34?mGy (thrice the dose by X-ray scanning) to 300?Gy (maximum dose from our X-ray equipment) was demonstrated, and the samples were evaluated by formulation tests.Results: Exposure to X-rays did not affect the pharmaceutical quality of the drug content. The samples exposed to X-rays exhibited almost the same profile in formulation tests (dissolution test, disintegrating test and hardness test) as control samples (0?Gy). The combination of X-ray exposure with accelerated temperature and humidity tests (six months) also did not affect the pharmaceutical quality. The color change of light-sensitive drugs (nifedipine and furosemide tablets) after X-ray exposure was negligible (1.0). In contrast, tablet color was remarkably changed by light from a D65 lamp.Conclusion: The X-ray scanning and X-ray exposure under our experimental conditions did not affect the pharmaceutical quality of drug tablets. 相似文献
383.
Syou Maki Chikako Udagawa Shotaro Morimoto Yoshifumi Tanimoto 《Microgravity science and technology》2014,26(2):125-130
We examined periodical oscillation phenomena that were observed during salt-water oscillator experiments under a small gravity condition. This condition was realized by situating a lower-density gadolinium chloride (GdCl 3) aqueous solution on a higher-density sodium chloride (NaCl) aqueous solution and applying a downward magnetic force. The GdCl 3 solution concentration was 0.15 mol/kg (density ρ=1.03×103 kg/m 3), and the NaCl concentration was varied to (A) 4.35 mol/kg (ρ=1.15×103 kg/m 3), (B) 3.79 mol/kg (ρ=1.12×103 kg/m 3), and (C) 2.49 mol/kg (ρ= 1.09×10 3 kg/m 3). The magnitude of magnetic flux density was varied from 0 to 4.00 T. As the magnetic flux density grew larger, the GdCl 3 solution was pulled downward by the magnetic force, and upward and downward flows were generated simultaneously at the orifice. These flows were accompanied by a periodical, locally thickened part. The thickened part was only observed when the magnetic force magnitude was small in cases (A) and (B). This flow pattern was not observed in case (C), in which a conventional salt-water oscillation was induced instead (C). In this paper we discuss new experimental results in which the oscillation cycles in cases (A) and (B) are strongly associated with the magnitude of the magnetic force and the density difference in the biphase solutions. 相似文献
384.
Akiyama H Nakamura K Harikai N Watanabe H Iijima K Yamakawa H Mizuguchi Y Yoshikawa R Yamamoto M Sato H Watai M Arakawa F Ogasawara T Nishihara R Kato H Yamauchi A Takahata Y Morimatsu F Mamegoshi S Muraoka S Honjoh T Watanabe T Sakata K Imamura T Toyoda M Matsuda R Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(6):325-331
Inter-laboratory evaluation studies were conducted for ELISA methods for allergic substances (peanuts). Extracts of biscuit, sauce, chocolate and butter spiked with peanut standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Peanut Protein ELISA Kit (Peanut kit) and a FASTKIT Peanut ELISA kit (Peanut ELISA kit) were mostly below 10%. Mean recoveries of the peanut standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of peanut standard protein in four food extracts were in the ranges of 15.2-49.7% and 3.0-28.3% for the Peanut kit and the Peanut ELISA kit, respectively. Reproducibility relative standard deviations of peanut standard protein in four food extracts were 23.5-44.4%, 9.6-28.4% for the Peanut kit and the Peanut ELISA kit, respectively. The detection limits of both ELISA methods were 2-2.5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of peanut protein levels in extracts of biscuit, sauce, chocolate and butter. 相似文献
385.
Deependra Kumar Jha Naoto Yorino Yoshifumi Zoka Yutaka Sasaki Yuki Hayashi Kajunoni Iwata Ryuji Oe 《IEEJ Transactions on Electrical and Electronic Engineering》2010,5(5):531-538
This paper proposes a framework that includes a penalty function incorporated stochastic dynamic programming (SDP) model in order to derive the operation policy of the reservoir of a hydropower plant, with an aim to reduce the amount of spill during operation of the reservoir. SDP models with various inflow process assumptions (independent and Markov‐I) are developed and executed in order to derive the reservoir operation policies for the case study of a storage type hydropower plant located in Japan. The policy thus determined consists of target storage levels (end‐of‐period storage levels) for each combination of the beginning‐of‐period storage levels and the inflow states of the current period. A penalty function is incorporated in the classical SDP model with objective function that maximizes annual energy generation through operation of the reservoir. Due to the inclusion of the penalty function, operation policy of the reservoir changes in a way that ensures reduced spill. Simulations are carried out to identify reservoir storage guide curves based on the derived operation policies. Reservoir storage guide curves for different values of the coefficient of penalty function α are plotted for a study horizon of 64 years, and the corresponding average annual spill values are compared. It is observed that, with increasing values of α, the average annual spill decreases; however, the simulated average annual energy value is marginally reduced. The average annual energy generation can be checked vis‐à‐vis the average annual spill reduction, and the optimal value of α can be identified based on the cost functions associated with energy and spill. © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
386.
Fujita T Guan P McKenna K Lang X Hirata A Zhang L Tokunaga T Arai S Yamamoto Y Tanaka N Ishikawa Y Asao N Yamamoto Y Erlebacher J Chen M 《Nature materials》2012,11(9):775-780
Distinct from inert bulk gold, nanoparticulate gold has been found to possess remarkable catalytic activity towards oxidation reactions. The catalytic performance of nanoparticulate gold strongly depends on size and support, and catalytic activity usually cannot be observed at characteristic sizes larger than 5 nm. Interestingly, significant catalytic activity can be retained in dealloyed nanoporous gold (NPG) even when its feature lengths are larger than 30 nm. Here we report atomic insights of the NPG catalysis, characterized by spherical-aberration-corrected transmission electron microscopy (TEM) and environmental TEM. A high density of atomic steps and kinks is observed on the curved surfaces of NPG, comparable to 3-5 nm nanoparticles, which are stabilized by hyperboloid-like gold ligaments. In situ TEM observations provide compelling evidence that the surface defects are active sites for the catalytic oxidation of CO and residual Ag stabilizes the atomic steps by suppressing {111} faceting kinetics. 相似文献
387.
Three crude glucoamylase preparations from Rhizopus sp., Chalara paradoxa and Aspergillus sp. K-27 were used to determine the digestibility of raw starches from eight sweet potato varieties. Granule sizes and amylose contents were also measured. The average granule sizes ranged between 10.5 and 14.2 μm. The amylose contents varied between 18.2 and 21.8%. The hydrolysis rates for the raw starches by any of the three glucoamylases were similar. However, starch of the variety Hi-starch had a slightly lower hydrolysis rate than other starches when Rhizopus sp, enzyme was used. 相似文献
388.
Habibuddin M. Hafiz Naoto Yorino Yutaka Sasaki Yoshifumi Zoka 《IEEJ Transactions on Electrical and Electronic Engineering》2013,8(2):116-122
High penetration of renewable energy in the future power system will pose a big problem to the load dispatch operation. The large disturbance and high forecast error must be considered when scheduling a limited number of controllable generators to follow rapid change in load. This paper proposes a dynamic economic load dispatch (DELD) problem approach based on the concept of a feasible operation region (FOR). FOR is defined as the region that committed generators may operate in to match the load profile without violating the ramp‐rate constraints. The DELD problem is solved in two stages. In the first stage, FOR of each generator is computed using recent real‐time forecasted load as well as renewable energy generation. In the second stage, a generation schedule is determined by solving the DELD problem interval by interval while considering ramp‐rate constraints and FOR constraints. The method can gives feasible solution for feasible load and specify the amount of compensation required for feasible solution for infeasible load. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
389.
Cell wall material was isolated from the residue obtained after the extraction of sweet potato starch by treatment with the α-amylase. The wall material was fractionated by successive extraction with various reagents. The pectic substance was mainly composed of uronic acid (47.1%) residues and contained galactose as the predominant neutral sugar residues. The hemicellulosic fraction was further fractionated by precipitation with iodine in the presence of calcium chloride to give two fractions, a iodine precipitatable-iodine complex (HC-IP) and a supernatant solution (HC-IS). The HC-IS fraction had a higher glucose content (53.4%), whereas the HC-IP fraction had a high content of xylose residues (35.1%). The HC-IP fraction consisted mainly of xylan, as judged by the degradation with purified xylanase. 相似文献