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61.
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
62.
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
63.
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
64.
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
65.
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
66.
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
67.
A Kawauchi Y Hashimoto K Kamiya H Hattori M Kusano 《Canadian Metallurgical Quarterly》1998,56(4):1049-1054
The utility of ultrasound color Doppler flow mapping imaging for the differential diagnosis on the breast and thyroid tumors had already reported in 1991. Ultrasound contrast agent, SH/TA 508 (Levovist; Schering AG, Germany), had already finished clinical trials in Japan and reported the result phase II, III. On the breast and thyroid lesions, the utility of this contrast agent are safety and usefulness for the accurate diagnosis by the ultrasound color Doppler examination. Throughout of these clinical trials, a quit new ultrasound Doppler imaging methods had been developed, Harmonic Imaging and acoustic emission mode. As the result, ultrasound contrast agent is useful not only for the conventional color Doppler diagnosis but also for the developing of new diagnostic imaging methods. 相似文献
68.
69.
6 groups of Ss held discussions during which the individuals' opinions and estimates of the group consensus were privately taken on various issues. "The degree of estimation accuracy achieved was not noticeably different from the accuracy found by other investigators under conditions of no discussion." (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
A prediction of fatigue life and fracture stress of ceramics of a heterogeneous system was made by application of fracture
mechanics based on slow crack growth. It was shown that the prediction of fatigue life and fracture stress in ceramics of
heterogeneous system in general could be dealt with in a similar way to those of ceramics of a homogeneous system. Experimental
examination of the validity of the prediction was made with LAS glass ceramics (Li2O-Al2O3-SiO2) at various stages of devitrification as well as foamed glass. These results proved the validity of the formulae derived. 相似文献