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91.
Periodical shedding of cloud cavitation from a single hydrofoil in high-speed cryogenic channel flow
In order to explain criteria for periodical shedding of the cloud cavitation, flow patterns of cavitation around a plano-convex
hydrofoil were observed using a cryogenic cavitation tunnel of a blowdown type. Two hydrofoils of similarity of 20 and 60
mm in chord length with two test sections of 20 and 60 mm in width were prepared. Working fluids were water at ambient temperature,
hot water and liquid nitrogen. The parameter range was varied between 0.3 and 1.4 for cavitation number, 9 and 17 m/sec for
inlet flow velocity, and −8° and 8° for the flow incidence angle, respectively. At incidence angle 8°, that is, the convex
surface being suction surface, periodical shedding of the whole cloud cavitation was observed on the convex surface under
the specific condition with cavitation number and inlet flow velocity, respectively, 0.5, 9 m/sec for liquid nitrogen at 192°C
and 1.4, 11 m/sec for water at 88°C, whereas under the supercavitation condition, it was not observable. Periodical shedding
of cloud cavitation occurs only in the case that there are both the adverse pressure gradient and the slow flow region on
the hydrofoil. 相似文献
92.
Monolayers of an amphiphilic nitrophenylazide (ANPA) derivative were prepared and their ability to immobilize a protein molecule by a photochemical binding reaction was demonstrated as a novel means to constitute a biofunctional membrane. Molecular orientations and photoreactions in the ANPA monolayers were investigated by Fourier transform IR spectroscopy. Rapid photolysis of ANPA was observed which reflects decomposition of the azide group to a reactive nitrene radical intermediate. As an enzyme, glucose oxidase (GOD) was immobilized on a monomolecular film of ANPA, coated on a substrate, by means of enzyme adsorption at the solid-solution interface and subsequent photolysis of ANPA. Radioisotope labelling experiments revealed that the enzyme was immobilized at a high surface concentration which corresponds to a closely packed monolayer of GOD. The specific activity of the immobilized enzyme was estimated to be high compared with those of other systems involving the adsorption of this enzyme. The usefulness of the present technique for fabricating biofunctional monolayer assemblies is discussed. 相似文献
93.
Hongo Takero Arakawa Hideo Sugimoto Gunji Tange Koichi Yamamoto Yuzo 《Industrial Electronics, IEEE Transactions on》1987,(1):5-10
An automatically guided vehicle, traveling without fixed guide ways, has been developed. In this paper, the construction of the vehicle, the control algorithm, and its general performance are described. 相似文献
94.
Ryuji Suyama Toshifumi Ashida Shoichi Kume 《Journal of the American Ceramic Society》1985,68(12):314-C
Single-phase orthorhombic ZrO2 was prepared by quenching from high temperature and high pressure. The lattice parameters are a0 =0.5042, b0 =0.5092, and c0 =0.5257 nm; the calculated density is 6.09 Mg·m−3 . This phase is metastable under atmospheric pressure and reverts to the monoclinic phase either on heating above 300°C or when it is ground in a mortar. 相似文献
95.
Koichi Awazu Xiamin Wang Junji Tominaga Hirohiko Aiba Tetsuro Komatsubara 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2009,267(6):941-943
It has been reported that elongated Au nanoparticles oriented parallel to one another can be synthesized in SiO2 by ion irradiation. Our aim was to elucidate the mechanism of this elongation. We prepared Au and Ag nanoparticles with a diameter of 20 nm in an SiO2 matrix. It was found that Au nanoparticles showed greater elongated with a higher flux of ion beam and with thicker SiO2 films. In contrast, Ag nanoparticles split into two or more shorter nanorods aligned end to end in the direction parallel to the ion beam. These experimental results are discussed in the framework of a thermal spike model of Au and Ag nanorods embedded in SiO2. The lattice temperature exceeds the melting temperatures of SiO2, Au and Ag for 100 ns after one 110 MeV Br10+ ion has passed through the middle of an Au or Ag nanorod. 相似文献
96.
Daisuke HirookaAuthor Vitae Koichi SuzumoriAuthor VitaeTakefumi KandaAuthor Vitae 《Sensors and actuators. A, Physical》2011,171(2):283-291
In this article, we report a new particle-excitation flow control valve. The purpose of this study is the development of a particle-excitation flow control valve that can precisely control pneumatic cylinders. We have reported this flow control valve principle. The valve, driven by a PZT vibrator, has a simple lightweight structure with large flow rate. We report the relationship between the orifice arrangement and flow rate characteristics of the valve. We have designed a new prototype for the purpose of high controllability. We have measured flow-rate characteristics and confirmed the conditions necessary for continuous adjustment of flow quantity. The control valve works successfully to realize a change in flow rate. 相似文献
97.
98.
99.
To develop a quantitative method for predicting shrinkage porosity in squeeze casting 总被引:1,自引:0,他引:1
In order to secure high strength and high elongation of suspension parts, it is critical to predict shrinkage porosity quantitatively. A new simulation method for quantitative predic'don of shrinkage porosity when replenishing molten metal has been proposed for squeeze casting process. To examine the accuracy of the calculation model, the proposed method was applied to a plate model. 相似文献
100.
Masayuki Machida Yoshinobu Terabayashi Motoaki Sano Noriko Yamane Koichi Tamano Gary A Payne Jiujiang Yu Thomas E Cleveland William C Nierman 《Food Additives & Contaminants》2008,25(9):1147-1151
Aspergillus oryzae has been used in Japanese fermentation industries for more than a thousand years. The species produces large amounts of various hydrolytic enzymes and has been successfully applied to modern biotechnology. The size of the A. oryzae genome (37.5 Mb) is very close to that of A. flavus and A. niger, and 20-30% larger than that of either A. nidulans or A. fumigatus. A. oryzae and A. flavus have exactly the same number of aspartic proteinase genes, of which each orthologous pair shares highly conserved amino acid sequences. Synteny analysis with A. fumigatus and A. nidulans showed that the A. oryzae genome has a mosaic structure consisting of syntenic and non-syntenic blocks. In the microorganisms to be compared, the density of the genes having homologs was obviously higher on the syntenic than on the non-syntenic blocks. Expression analysis by the DNA microarray supported the significantly lower expression of genes on the non-syntenic than on the syntenic blocks. 相似文献