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排序方式: 共有438条查询结果,搜索用时 15 毫秒
371.
Naoyuki Takahashi Takato Nakumura Yoshinori Kubo Katsumi Tamanuki 《Journal of Physics and Chemistry of Solids》2005,66(7):1145-1149
Crystalline quartz films with an AT-cut plane have been grown by catalyst-enhanced vapor-phase epitaxy, at atmospheric pressure, using two quartz buffer layers on a sapphire (110) substrate. In this method, the first quartz buffer layer was deposited on the sapphire (110) substrate at 773 K. After annealing at 823 K, the second buffer layer was deposited at 723 K. The crystal quartz epitaxial layer was then grown at 843 K. The X-ray full-width-at-half-maximum (FWHM) value of the crystalline quartz film obtained was smaller than that of crystalline quartz prepared using a hydrothermal process. The crystalline quality of the quartz films was dependent on the thickness of the buffer layers. Furthermore, it was found that angle control of the cut plane depended on the film thickness of the second buffer layer. The quartz films grown by vapor phase epitaxy show good oscillation characteristics at room temperature. 相似文献
372.
Naoyuki Takahashi Yoriko Matsumoto Takato Nakamura 《Journal of Physics and Chemistry of Solids》2006,67(4):665-668
Aluminum nitride (AlN) prepared under atmospheric pressure using a halide chemical vapor deposition method has been examined by means of a variety of analytical techniques. Scanning electron microscopic observations showed that the crystals deposited onto a Si(100) substrate have hexagonal pillar structure. Based on the X-ray diffraction and X-ray pole-figure analyses, it was deduced that the each AlN pillar crystal grows with a different rotation angle around the 〈001〉 axis. Transmission electron diffraction showed that they are of single-like form. This was also confirmed by the selected area electron diffraction image as well. It was found that the diameter of pillar which constitutes an AlN film was significantly dependent upon the ratio of NH3/AlCl3 used as source materials and the growth temperature. 相似文献
373.
374.
Naoyuki Koike 《Results in Mathematics》2005,48(1-2):97-108
We give constructions of Blaschke Dupin hypersurfaces and a Blaschke isoparametric ones in terms of the notion of an equiaffine tube. In particular, the construction of Blaschke isoparametric hypersurfaces includes the Calabi-type composition of improper affine spheres (or an improper one and a proper one). 相似文献
375.
Naoyuki Koike 《Results in Mathematics》2005,47(1-2):69-92
The main purpose of this paper is to investigate the quadraticity of slices (i.e., leaves of curvature foliations) of a non-degenerate equiaffine Dupin hypersurface, where an equiaffine Dupin hypersurface is the notion defined as the equiaffine geometrical version of a (not necessarily complete) Dupin hypersurface. 相似文献
376.
Horiguchi Y Honda K Kato Y Nakashima N Niidome Y 《Langmuir : the ACS journal of surfaces and colloids》2008,24(20):12026-12031
Photothermal reshaping of gold nanorods was triggered by pulsed-laser irradiation. The efficiency of the reshaping was strongly dependent on the surface conditions of the gold nanorods. When the gold nanorods were dispersed in concentrated hexadecyltrimethylammonium bromide (CTAB), the gold nanorods were efficiently transformed into a phi-shape. By comparison when poly(styrene sulfonate), poly(vinylpyrrolidone), poly(ethylene glycol), or phosphatidylcholine layers were used, the CTAB layers were found to be a better thermal insulator that helped to enhance the photothermal reshaping of the gold nanorods. 相似文献
377.
Miwatashi S Arikawa Y Matsumoto T Uga K Kanzaki N Imai YN Ohkawa S 《Chemical & pharmaceutical bulletin》2008,56(8):1126-1137
To investigate the potency of an adenosine A3 receptor (A3AR) antagonist as an anti-asthmatic drug, a novel series of 4-phenyl-5-pyridyl-1,3-thiazole derivatives was synthesized and evaluated in human adenosine A1, A2A and A3 receptor and rat adenosine A3 receptor binding assays. From investigation of the SAR study, compound 7af was identified as a highly potent human and rat A3AR antagonist. This compound inhibited IB-MECA-induced plasma protein extravasation in the skin of rats and showed good oral absorption. Also, compound 7af significantly inhibited antigen-induced hyper-responsiveness to acetylcholine in actively sensitized Brown Norway rats. These results show that 4-phenyl-5-pyridyl-1,3-thiazole derivatives are potential candidates to enable the evaluation of A3AR antagonists. Further evaluation of this class of compounds may afford a novel anti-inflammatory agent such as an anti-asthmatic drug. 相似文献
378.
Arai T Horiguchi M Yanagida M Gunji T Sugihara H Sayama K 《Chemical communications (Cambridge, England)》2008,(43):5565-5567
Acetaldehyde was completely oxidized to CO(2) over a Pd/WO(3) photocatalyst under fluorescent-light irradiation in a flow-type reactor, and Pd/WO(3) was also used to completely oxidize toluene to CO(2) in a batch reactor under visible-light irradiation. 相似文献
379.
Masakatsu Matsumoto Nobuko Watanabe Naoyuki Hoshiya Hisako K. Ijuin 《Chemical record (New York, N.Y.)》2008,8(4):213-228
Dioxetanes bearing an aromatic electron donor decompose with an accompanying emission of light by an intramolecular charge‐transfer‐induced chemiluminescence (CTICL) mechanism. The color of the chemiluminescence from CTICL‐active aryl‐substituted dioxetanes is controlled by the design of the aromatic moiety and its substitution pattern, and the substituent on the carbon of the dioxetane ring. In addition to these color modulations, a change in the conformation of dioxetanes bearing a biaryl group was also found to cause a change in the color of CTICL in the coordination sphere of a crown ether complex. This new color modulation system was further developed for optically active dioxetanes bearing 2‐hydroxy‐1,1′‐binaphthyl, the CTICL of which took place under the chiral recognition of optically active crown ether complexes. The spectra of the chemiluminescence from biaryl‐type dioxetanes did not coincide with the fluorescence spectrum from the authentic emitter in the coordination sphere, but they did coincide with each other in a completely homogeneous system. This finding suggests that the emitter of CTICL possesses a transient structure, which retains the afterimage of the conformation of the dioxetane. © 2008 The Japan Chemical Journal Forum and Wiley Periodicals, Inc. Chem Rec 8: 213–228; 2008: Published online in Wiley InterScience ( www.interscience.wiley.com ) DOI 10.1002/tcr.20150 相似文献
380.