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排序方式: 共有1368条查询结果,搜索用时 156 毫秒
91.
Noriko Saruta Toshiro Fukami Takayuki Furuishi Toyofumi Suzuki Kazuo Tomono 《Advanced Powder Technology》2010,21(3):326-330
Teprenone (Tp) is a widely used pharmaceutically active ingredient in terpene anti-ulcer agents. We investigated Tp and cyclodextrin (CD) complexes for the objective of forming stable Tp powders. Tp was combined with each CD at a molar ratio of 1:2, kneaded together while adding an appropriate amount of water, then dried under reduced pressure and lightly milled into a powder to produce a kneaded mixture (KM). Powder X-ray diffraction of KM containing Tp and β- and γ-CD revealed new diffraction peaks. On infrared spectroscopy, the peak near 1718 cm?1 corresponding to the carbonyl group of Tp had shifted to around 1701 cm?1. Solid-state NMR spectroscopy showed signs of inhibited molecular mobility of Tp, which is liquid at room temperature, confirming that Tp had formed complexes with β- and γ-CD. Photostability analysis of Tp showed improved stability in the order of γ-CD > β-CD ? α-CD. 相似文献
92.
Kimihiro Yamanaka Takafumi Ooyoshi Takayuki Nejime 《Journal of Materials Science: Materials in Electronics》2010,21(1):53-57
Measuring the real temperature of a flip chip solder joint during an electromigration test has been a problem because of its
small size and the local Joule heating due to a large applied current. A unique method that employs the electrical resistance
change in the junction line between two solder joints was introduced to determine the temperature of the solder joint. The
change in resistance was converted into temperature using a thermal coefficient of resistance of the junction line. The method
accurately measured temperatures of the solder joint within 2 K until the solder joint resistance change ratio reached 100%
due to growth of an electromigration void. 相似文献
93.
In this paper, we describe a new model of immune network based on biological immune response network. We propose an immunity like multiple‐valued network with apoptosis mechanism. The model is based on the interaction between B cells and T cells and the biological apoptosis mechanism in the human body. With the mechanism, a naturally immune system can be reproduced. The model is also applied to pattern recognition. It becomes possible with a conventional model to restrict the category increase of memory patterns. © 2007 Wiley Periodicals, Inc. Electr Eng Jpn, 162(3): 51– 57, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20320 相似文献
94.
95.
The elastic shear modulus of natural sedimentary clay ground, Gmax, is estimated based on laboratory tests for fifteen different reconstituted clays. Two types of tests were performed, i.e., Bender Element and Cyclic Triaxial tests. The proposed formulation is not based on void ratio, e, but consists of only three parameters: wL (liquid limit), p′ (the current mean effective stress) and p′max (the maximum mean consolidation pressure). To apply it to the field, this equation is modified for using σ′v0 (the in situ effective overburden pressure) and OCR, instead of p′ and p′max. Since existing formulae for Gmax are mostly based on e, they are not able to apply to both reconstituted soil and field, without considering the correction factor for structure. This is because e in the field is much larger than that for reconstituted soil even though their consolidation pressures and OCR are the same for these clays. The applicability of the proposed formula was examined by using investigated results from the in-situ seismic surveys performed at eleven worldwide sites. It is well demonstrated that the proposed equation in this paper is capable of predicting Gmax of natural sedimentary clay deposits with higher accuracy than the existing empirical formulae using a function of e. 相似文献
96.
Makoto Wakabayashi Takayuki Kohno Tokutaro Kimura Satoshi Tamura Masahiko Endoh Satoru Ohnishi Toshikatsu Nishioka Yoshikatsu Tanaka Toshitaka Kanai 《应用聚合物科学杂志》2007,106(2):1398-1404
Many additives are commercially used to add more favorable qualities to films. The bleeding process by which the additive in a film comes to the surface is considered. A new bleeding model of additives in a polypropylene film under atmospheric pressure was investigated. Solubility and diffusion are found to be important for explaining this bleeding process. It was found that the experimental results were explained more precisely by assuming a two‐step transport process between the crystalline regions and the amorphous ones. The solubilities and diffusion coefficients of UV‐stabilizers such as 2‐(2H‐benzotriazol‐2‐yl)‐4‐(1,1,3,3‐tetramethylbutyl)phenol and 2‐(2H‐benzotriazol‐2‐yl)‐4‐methylphenol were determined at 40°C. The difference between the saturation solubilities and the diffusion coefficients of UV‐stabilizers was discussed by comparing with the results of molecular dynamics (MD) simulation. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007 相似文献
97.
Pradyumna Gupta Himanshu Jain David B. Williams Tsuyoshi Honma Yasuhiko Benino Takayuki Komatsu 《Journal of the American Ceramic Society》2008,91(1):110-114
Using a novel, selective heating by Nd:YAG laser, a single-crystal architecture is created in a model glass system, Sm0.5 La0.5 BGeO5 , which devitrifies congruently into a ferroelectric phase of the same composition as the parent glass. The Sm3+ ions in glass absorb the light and heat the matrix locally resulting in devitrification. Initially, a polycrystalline spot is formed. However, with optimum laser power, scanning speed, and the depth of focus, one of the grains acts as the seed for further growth as a single crystal. By programming the relative displacement of the glass with respect to laser spot, desired single ferroelectric crystal architecture is created. The optical functionalities (guiding of light and second harmonic generation) of the architectures are shown, which demonstrate the viability of this method for constructing active elements in optical integrated circuits. The single-crystal nature of the architecture is confirmed from the electron backscattered diffraction results. 相似文献
98.
Akira Tachibana Kazuo Tohiguchi Takayuki Ueno Yuichi Setogawa Ayako Harada Toshizumi Tanabe 《Journal of Bioscience and Bioengineering》2009,107(6):668-669
Ligation-independent cloning (LIC) is a useful method for efficient directional cloning of a PCR product. LIC requires a specially designed vector containing a long stretch of sequence that is missing any one of the four nucleotides. When the linearized vector is treated with T4 DNA polymerase, in the presence of the absent base, long single-stranded overhangs are generated that are suitable for cloning. In this study, long and efficient sticky ends for LIC were produced by sequential T4 DNA polymerase treatments at non-specific sequences on a commercially available vector. All restriction enzyme sites become available in the current LIC. 相似文献
99.
Takayuki Tsukada Sridhar Venigalla James H. Adair 《Journal of the American Ceramic Society》1997,80(12):3187-3192
The feasibility of synthesizing crystalline ZrO2 films at low temperatures was evaluated using an electrochemical method. Anodization of zirconium-metal substrates in tetraethyl ammonium hydroxide (TEAOH) solutions under constant applied voltage conditions at ∼25° and ∼100°C was investigated. The chemistry and microstructure of the anodic oxide films deposited on the zirconium-metal substrates under the above conditions were characterized using X-ray diffractometry and scanning electron microscopy. The results indicated that, with sufficiently high applied voltages (in the range of 300 V) at pH ∼9.5, the initial dissolution of the zirconium anode resulted in the local saturation of the electrolyte solution with Zr4+ , forming Zr(OH)− 5 , which deposited electrophoretically on the anode as a thick, gelatinous film at 25°C. Similar treatments at 100°C resulted in an in situ crystallization of Zr(OH)4 gel to monoclinic ZrO2 . 相似文献
100.