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101.
102.
Hirose M. Matsushige S. Buma S. Kamiya K. 《Industrial Electronics, IEEE Transactions on》1988,35(2):193-200
An electronically controlled air-suspension system is described that uses sensors to detect vehicle speed, throttle position, steering angle, height, and other factors related to vehicle attitude. Its electronic control unit (ECU) drives the actuators to control spring rate, damping force, and height. As a result, the system reduces changes in vehicle attitude such as rolls, dives, squats, etc., and also provides stable maneuverability in high-speed cruising and improved drive characteristics on rough roads. A newly developed single-chip microcomputer is used in the ECU. The actuators for the sporting rate and damping force use DC motors. The system also allows drivers to select preferred suspension characteristics from four modes, and displays on a CRT the suspension status 相似文献
103.
K Uesaka Y Nimura J Kamiya M Nagino M Kanai N Yuasa 《Canadian Metallurgical Quarterly》1998,25(8):1131-1136
This study defines normative flow velocity (FV) ranges for the common carotid (CCA), internal carotid (ICA) and middle cerebral arteries (MCA), compares them to subjects with nonfocal vascular disease (mild to moderate hypertension, diabetes, hyperlipidemia or coronary artery disease), and clarifies the association between carotid and MCA FVs. FVs were measured by carotid and transcranial Doppler ultrasonography in 278 healthy and 190 vascular-disease subjects. Normative FV ranges for CCA, ICA and MCA were large in healthy subjects, with modest gender and age differences. Vascular-disease subjects had similar FVs to healthy controls. MCA FVs were significantly correlated with carotid FVs (r ranged 0.26-0.50), but were only weakly or not significantly associated with them (beta ranged 0.08-0.18) when controlling for age and gender. These findings suggest that normative FVs are not affected by the presence of nonfocal vascular disease, but carotid FVs do not aid in assessing MCA FVs. 相似文献
104.
Mori S. Araki Y.Y. Sato M. Meguro H. Tsunoda H. Kamiya E. Yoshikawa K. Arai N. Sakagami E. 《Electron Devices, IEEE Transactions on》1996,43(1):47-53
This paper describes the scaling limitation factors of ONO interpoly dielectric thickness, mainly considering the charge retention capability and threshold voltage stability for nonvolatile memory cell transistors with a stacked-gate structure, based on experimental results. For good intrinsic charge retention capability, either the top- or bottom-oxide thickness should be greater than around 6 nm. On the other hand, a thicker top oxide structure is preferable to minimize degradation due to defects. It has been confirmed that a 3.2 nm bottom-oxide shows detectable threshold voltage instability, but 4 nm does not. Effective oxide thickness scaling down to around 13 nm should be possible for flash memory devices with a quarter-micron design rule 相似文献
105.
Patricia Amouzegh Annie Finiels Patrick Geneste Erick Ginestar Patrice Moreau 《Catalysis Letters》1995,34(3-4):389-394
The acylation reaction of 2-butylbenzofuran withp-anisoyl chloride andp-anisic acid in the presence of faujasite type zeolites, in the liquid phase, is reported. A good initial selectivity to the 3-acylated derivative is obtained, but the selectivity decreases with time. This result is explained by the involvement of a deacylation-reacylation process. 相似文献
106.
T Kouyama M Yamamoto N Kamiya H Iwasaki T Ueki I Sakurai 《Canadian Metallurgical Quarterly》1994,236(4):990-994
A novel ordered assemblage of bacteriorhodopsin, a transmembrane protein functioning as a light-driven proton pump, is found in its three-dimensional crystal. Atomic force microscope images of the crystal surface reveal that spherical protein clusters with a diameter of approximately 50 nm are hexagonally close-packed. Electron micrographs of mechanically disintegrated crystals show that the inside of the protein cluster is filled with the mother liquor. The crystal is made up of hollow protein clusters. When disintegrated crystals are illuminated in the presence of a lipophilic anion, a significant alkalization of the external medium occurs. This result indicates that the protein cluster contains native lipids and that the cytoplasmic side of the protein faces the external medium. X-ray diffraction patterns and the observed diameter of the spherical shell suggest that approximately 200 bacteriorhodopsin trimers are aligned on a polyhedral surface lattice. Another remarkable feature of the spherical assemblies of bacteriorhodopsin is that they fuse with each other at low ionic strength and occasionally form a tubular or doughnut-like structure. The concept of membrane protein polymorphism is introduced on the basis of these observations, and it is used to describe the dynamic structure of some other biological membranes. 相似文献
107.
Kanichi Kamiya Tokiti Noda Michio Inagaki Hajime Saito 《Journal of Materials Science》1972,7(11):1244-1248
A soft carbon and a hard carbon which were prepared from Polyvinylchloride and phenolformaldehyde resin, respectively, both by carbonizing to about 700°C, were obtained as sintered cakes by heat-treatment up to about 1800°C under the quasihydrostatic pressure of 5 kbar. Preferred orientation of crystallites relative to the compressing direction in these cakes was determined by X-ray difraction technique by using the (004) or (002) diffraction line. The soft carbon showed remarkable preferred orientation of crystallites, but the degree of orientation was dependent only a little on heat-treatment temperature (HTT). At 1200°C under 5 kbar, the hard carbon gave a sintered cake which had no appreciably preferred orientation. The degree of preferred orientation of crystallites in the cake of the hard carbon greatly increased with the increase in HTT. The difference in the dependence of preferred orientation of crystallites in the soft and hard carbons on HTT was interpreted by referring to the texture of the original carbons. 相似文献
108.
T. Ohta N. Kamiya M. Yamaguchi N. Gotoh T. Otagawa S. Asakura 《International Journal of Hydrogen Energy》1978,3(2):203-208
Valuable hybrid systems for hydrogen production by solar energy have been developed and the system efficiency has been estimated and discussed from various points of view. In order to decompose water into hydrogen and oxygen without the consumption of additional reactants, a steady stream of the reacting materials must be maintained in consecutive reaction processes and if the system has a rate determining step extra energy should be supplied to promote the reaction. In the Yokohama Mark 5 Process, the efficiency of the thermoelectric device is as low as 5 %; however, the overall efficiency of hydrogen production can be raised to 20 % by addition of extra electric power.The energetics of a hybrid system combining photochemical, thermochemical and electrochemical reactions have also been discussed. 相似文献
109.
The laminate method for studying the permeability and diffusivity of moistened cellophane to gases is described and the humidity dependence of the transport parameters for H2, He, and Ne is presented. In the relative humidity region of about 0% to 60%, a small increase in the permeability was observed, which is caused by a comparatively small increase in the diffusivity owing to the plasticizing effect of sorbed water and a decrease in the solubility. On the other hand, an extremely large increase in the permeability observed in the relative humidity region above 60% is mainly based on the diffusion coefficient of gas enhanced by the swelling effect of sorbed water. The presence of a minimum in the solubility–relative humidity curves has been confirmed and is discussed. 相似文献
110.
In order to decompose endocrine disruption chemicals (EDCs) in sewage effluent, ozone based oxidation of nonylphenol (NP), bisphenol A (BPA) and 17β-estradiol (E2) was investigated. Experimental results showed that these EDCs were decomposed easily even in the presence of other organic substances of TOC 5 mg/L. The simulation using kinetic constants obtained from the experiments indicated that these EDCs in sewage effluent were removed to below the detection limit with an amount of ozone consumed less than 0.5 mg/L. Ozonation also reduced the estrogenic activity and the aquatic acute toxicity of these EDCs solution. From these results it was concluded that ozonation was very effective in decomposing these EDCs in sewage effluent. 相似文献