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111.
Hydrocracking of diphenylmethane and tetralin over bifunctional NiW sulfide catalysts supported on three kinds of zeolites 总被引:1,自引:0,他引:1
Koichi Sato Yoshiki Iwata Toshikazu Yoneda Akio Nishijima Yasuo Miki Hiromichi Shimada 《Catalysis Today》1998,45(1-4):367-374
Hydrocracking reactions of diphenylmethane and tetralin were carried out over three kinds of zeolites with or without NiW sulfide to discuss the roles of catalytic bifunctionality in two types of hydrocracking reactions. It was found that strong acid sites were not needed for the hydrocracking of diphenylmethane, while the conversion of tetralin required relatively strong acid sites. Ultra-stable Y zeolite with strong acidity exhibited high hydrocracking activity for both reactions. In contrast, mordenite catalysts did not show high activity for either hydrocracking, though isomerization of tetralin and excess hydrocracking to gaseous products proceeded. The superior performances of ultra-stable Y zeolite in the tetralin hydrocracking were suggested to be related to the hydrogen transfer ability. In most cases, the loading of NiW sulfide enhanced catalytic activity. In the diphenylmethane hydrocracking, the role of NiW sulfide was found to supply active hydrogen to the hydrocracking active sites on zeolite and to prevent polymerization of benzyl cations. In the tetralin hydrocracking, the dehydrogenated products from tetralin were re-hydrogenated over NiW sulfide. 相似文献
112.
The location of the egocenter in kinesthetic space was investigated in 4 experiments. Participants, with their eyes closed, adjusted a comparison stimulus after or while touching a standard in a transverse plane at the belly or shoulder level so that they perceived the line joining the comparison and the fixed standard as pointing directly at themselves. The mean location of the intersections of the obtained lines was taken as the location of the egocenter. The main results showed that the location of the kinesthetic egocenter depended on the hand or hands used for touching, the timing of touching, and the distance of the standard from the participant. Implications of these results were discussed in relation to models of the kinesthetic egocenter. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
113.
Chlorophyll-a (Chl-a) assembled in hydrophobic domain by fatty acid with long alkyl hydrocarbon chain such as myristic acid (Myr), stearic acid (Ste) and cholic acid (Cho) modified onto nanocrystalline TiO2 electrode is prepared and the photovoltaic properties of the nanocrystalline TiO2 film by Chl-a are studied. Incident photon to current efficiency (IPCE) value at 660 nm in photocurrent action spectrum of Chl-a/Ste-TiO2, Chl-a/Myr-TiO2 and Chl-a/Cho-TiO2 electrodes are 5.0%, 4.1% and 4.1%, respectively. Thus, the IPCE is maximum using Chl-a/Ste-TiO2 electrode. From the results of photocurrent responses with light intensity of 100 mW cm−2 irradiation or monochromatic light with 660 nm, generated photocurrent increases using Chl-a/Ste-TiO2 electrode compared with the other Chl-a assembled TiO2 electrodes. These results show that the hydrophobic domain formed by stearic acid with long alkyl hydrocarbon chain is suitable for fixation of Chl-a onto TiO2 film electrodes and photovoltaic performance is improved using Chl-a onto Ste-TiO2 film electrode. 相似文献
114.
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
115.
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
116.
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
117.
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
118.
119.
120.
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