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排序方式: 共有993条查询结果,搜索用时 265 毫秒
971.
Akihisa Kubota Yohsuke Shinbayashi Hidekazu Mimura Yasuhisa Sano Kouji Inagaki Yuzo Mori Kazuto Yamauchi 《Journal of Electronic Materials》2007,36(1):92-97
Elastic emission machining (EEM) is a precise surface preparation technique, which uses chemical reactions between the surfaces
of the workpiece and fine powder particles. The purpose of this study is to clarify the surface removal process of silicon
carbide (SiC) in EEM. A SiC sample with a periodic step-bunched structure was prepared as the initial surface and was flattened
by EEM. Optical interferometer and atomic force microscopy (AFM) observations show that the topmost areas on the periodic
step-bunched structure in contact with the powder particles are preferentially removed and surface protrusion is gradually
reduced as removal depth increases. Moreover, power spectral density analyses reveal that the surface is smoothed in the spatial
wavelength range from 0.07 μm to 10 μm. 相似文献
972.
Hideyuki Hara Yasuhisa Sano Keita Yagi Akihisa Kubota Kazuto Yamauchi 《Science and Technology of Advanced Materials》2007,8(3):162-165
A Si wafer and polysilicon deposited on a Si wafer were planarized using catalyst-referred etching (CARE). Two apparatuses were produced for local etching and for planarization. The local etching apparatus was used to planarize polysilicon and the planarization apparatus was used to planarize Si wafers. Platinum and hydrofluoric acid were used as the catalytic plate and the source of reactive species, respectively. The processed surfaces were observed by optical interferometry, atomic force microscopy (AFM) and scanning electron microscopy (SEM). The results indicate that the CARE-processed surface is flat and undamaged. 相似文献
973.
Using backscattered electron (BSE) imaging and scanning electron microscopy, subsequent to a combined treatment of sodium hypochlorite (NaOCl) and ethylenediamine tetra-acetic acid (EDTA) or only with EDTA etching, we observed some structures of non-collagenous calcified matrixes with the aim of revealing the correlation of deposition between calcification degree and organic amount. In human tooth enamel, the NaOCl-EDTA method eroded more intensively the hypocalcified prisms of enamel tufts containing a relatively large amount of EDTA-insoluble organic matter than the hypercalcified normal prismatic enamel containing a small amount of the organic matter. Afibrillar cementum, one of the non-collagenous calcified tissues similar to the enamel, has been reported to consist of organic-rich and poor incremental lamellae. The BSE imaging showed an alternation pattern of hypocalcification and hypercalcification. The hypocalcified lamellae were retained by EDTA etching, while the hypercalcified lamellae showed a resistance against the NaOCl-EDTA method. In the non-collagenous calcareous concretions of human pineal body, organic-rich and poor, and hyper- and hypocalcified incremental lamellae have been reported. The deposition pattern of calcification degree and organic amount was similar to that in afibrillar cementum, and the hypercalcified lamellae showed a resistance against the NaOCl-EDTA method. In conclusion, the high and the lower calcified regions of non-collagenous calcified matrixes contained smaller and larger amounts of EDTA-insoluble organic matter respectively. Moreover, scanning electron microscopy subsequent to the NaOCl-EDTA method corresponding to the BSE imaging clearly showed fine calcified structures compared with the BSE imaging. 相似文献
974.
Katsuhiko Ariga Taizo Mori Takashi Kitao Takashi Uemura 《Advanced materials (Deerfield Beach, Fla.)》2020,32(41):1905657
Exploration of molecular functions and material properties based on the control of chirality would be a scientifically elegant approach. Here, the fabrication and function of chiral-featured materials from both chiral and achiral components using a supramolecular nanoarchitectonics concept are discussed. The contents are classified in to three topics: i) chiral nanoarchitectonics of rather general molecular assemblies; ii) chiral nanoarchitectonics of metal–organic frameworks (MOFs); iii) chiral nanoarchitectonics in liquid crystals. MOF structures are based on nanoscopically well-defined coordinations, while mesoscopic orientations of liquid-crystalline phases are often flexibly altered. Discussion on the effects and features in these representative materials systems with totally different natures reveals the universal importance of supramolecular chiral nanoarchitectonics. Amplification of chiral molecular information from molecules to materials-level structures and the creation of chirality from achiral components upon temporal statistic fluctuations are universal, regardless of the nature of the assemblies. These features are thus surely advantageous characteristics for a wide range of applications. 相似文献
975.
Nanorods: Discotic Liquid Crystal‐Functionalized Gold Nanorods: 2‐ and 3D Self‐Assembly and Macroscopic Alignment as well as Increased Charge Carrier Mobility in Hexagonal Columnar Liquid Crystal Hosts Affected by Molecular Packing and π–π Interactions (Adv. Funct. Mater. 8/2015)
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Xiang Feng Lydia Sosa‐Vargas S. Umadevi Taizo Mori Yo Shimizu Torsten Hegmann 《Advanced functional materials》2015,25(8):1161-1161
976.
Taizo Kobayashi Hiroshi Yamaguchi Zacharie Jehl Li Kao Hiroki Sugimoto Takuya Kato Hideki Hakuma Tokio Nakada 《Progress in Photovoltaics: Research and Applications》2015,23(10):1367-1374
In this work, the impacts of surface sulfurization of high‐quality Cu(In1−x,Gax)Se2 (CIGS) thin films deposited by three‐stage process on the film properties and the cell performance were investigated. The CIGS thin films were sulfurized at 550 °C for 30 min using H2S gas. The X‐ray photoelectron spectroscopy analysis revealed that sulfur atoms diffused into the CIGS surface layer and that the valence band minimum was lowered by the film sulfurization. The open circuit voltage (Voc) drastically increased from 0.590 to 0.674 V as a result of the sulfurization process. Temperature‐dependent current–voltage and capacitance–frequency measurements also revealed that interface recombination was drastically decreased by the lowering of the defect's activation energy level at the vicinity of the buffer/CIGS interface after the sulfurization. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
977.
Suzuki A Ivandini TA Yoshimi K Fujishima A Oyama G Nakazato T Hattori N Kitazawa S Einaga Y 《Analytical chemistry》2007,79(22):8608-8615
Highly boron-doped diamond (BDD) was deposited on chemically etched micrometer-sized tungsten wires using microwave plasma assisted chemical vapor deposition (MPCVD), and these were used to fabricate BDD microelectrodes. BDD microelectrodes with very small diameter (about 5 microm) and 250 microm in length could be made successfully. In addition to the unique properties of BDD electrodes, such as a very low background current, high stability, and selective oxidation of dopamine (DA) in the presence of ascorbic acid (AA), other superior properties of the microelectrodes, including a constant current response, an increase in the mass transport, and the ability for use in high resistance media were also shown. An application study was conducted for in vivo detection of DA in mouse brain, where the BDD microelectrode was inserted into the corpus striatum of the mouse brain. A clear signal current response following medial forebrain bundle (MFB) stimulation could be obtained with high sensitivity. Excellent stability was achieved, indicating that the BDD microelectrodes are very promising for future in vivo electroanalysis. 相似文献
978.
Hiroshi Sano 《Water research》1976,10(2):139-142
The toxicity of sulfite to fish decreases with increasing pH value, because the HSO−3 ion is more toxic than the SO2−3 ion. An effective sulfite concentration Seff which is proportional to the toxicity on fish, is expressed by the following equation: Seff=[HSO−3]+ƒ[SO2−3]where ƒ is a coefficient which expresses the change of toxicity of sulfite depending on the pH of the water, and varies for each species of fish. For goldfish, owing to the very small toxic contribution of SO2−3 ion (ƒ = 0·07), the pH dependence of the toxicity of sulfite on pH was so strong that sulfite seemed almost non-toxic in basic solution. However, ƒ for guppy is somewhat larger (ƒ = 0·20) so that the toxicity of sulfite weakly depends on the pH value of water. 相似文献
979.
Taizo Kobayashi Hiroshi Yamaguchi Tokio Nakada 《Progress in Photovoltaics: Research and Applications》2014,22(1):115-121
The impacts of air annealing, light soaking (LS), and heat–light soaking (HLS) on cell performances were investigated for ZnS(O,OH)/Cu(In,Ga)Se2 (CIGS) thin‐film solar cells. It was found that the HLS post‐treatment, a combination of LS and air annealing at 130 °C, is the most effective process for improving the cell performances of ZnS(O,OH)/CIGS devices. The best solar cell yielded a total area efficiency of 18.4% after the HLS post‐treatment. X‐ray photoelectron spectroscopy showed that the improved cell performance was attributable to the decreased S/(S + O) atomic ratio, not only in the surface region but also the interface region between the ZnS(O,OH) and CIGS layers, implying the shift to an adequate conduction‐band offset at the ZnS(O,OH)/CIGS interface. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
980.
A carbon nanotube–enhanced SiC (CNT–SiC) coating was deposited on C/C composites to improve the oxidation resistance of C/C. The CNT–SiC coating was prepared by direct growth of CNTs on C/C surface at 700 °C followed by deposition of SiC using chemical vapor deposition at 1150 °C for 1 h. SiC was deposited on the CNTs as well as the interface between CNTs and C/C, making CNTs strongly rooted on C/C surface. The final CNT–SiC coating consisted of two layers: the CNT–SiC layer and SiC layer. In comparison to the SiC coating, the CNT–SiC coating showed fewer cracks and a better oxidation resistance because the CNTs reduce the stress in the coating caused by the mismatch of the coefficient of thermal expansion between C/C and SiC. 相似文献