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排序方式: 共有276条查询结果,搜索用时 15 毫秒
1.
K. Nomoto H. Saitoh A. Chida H. Sannomiya M. Itoh Y. Yamamoto 《Solar Energy Materials & Solar Cells》1994,34(1-4)
a-Si alloy three-stacked solar cells have been studied to improve the stabilized efficiency of a-Si: H based solar cells. Based on the analysis by the individual characterization method of the component cells in stacked type cells, the a-Si :H middle cell was replaced with an a-SiGe :H cell. Furthermore, the optical confinement technology was improved to obtain a high-output current with thin i-layer thickness in the a-SiGe :H bottom cell. By this device design, the initial conversion efficiency was improved up to 12.4% and more than a 10% stabilized efficiency was obtained in a-SiC :H/a-SiGe :H/a-SiGe :H three-stacked cells. These cell characteristics were confirmed by measurements at the JQA Organization (the former JMI Institute). 相似文献
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Photocatalytic activities for water decomposition were examined for photocatalysts using hexa- and octa-titanates and TiO2(B) with different tunnel space in the structure. Using RuO2 as promoter, M2Ti6O13 (M = Li, Na, K, Rb) showed the stoichiometric production of Hz and O2 except for Li, whereas H2Ti8O17 and TiO2(B) had very low activity producing only hydrogen as a product. The effects of promoters on Na2Ti6O13 showed that the activity increased in the order of RuO2 > RuO2 + IrO2 > IrO2 > RuO2 + Pt > MnO2. These effects along with other related ones are discussed: it emerges that the presence of the tunnels is important for the achievement of high photocatalytic activity. 相似文献
4.
Keiji Mimura Susumu Yukawa Yoshio Mori Kazuya Okada Masatoshi Mune Osamu Nishikawa Akira Hibino Miyahiko Sonobe Tetuya Goto Hiroshi Nomoto 《Lipids》1991,26(12):1102-1107
We investigated the effect of platelet-activating factor (PAF) and of the PAF specific antagonist CV-6209 on plasma lipid
metabolism, and particularly on post-heparin plasma lipolytic activity in male Wistar rats. Lipoprotein lipase (LPL) activity
was enhanced by intravenous injection of PAF before intravenous injection of heparin when the PAF dose was low (0.2 μg/kg).
PAF activated hepatic triacylglycerol lipase (HTGL) activity dose-dependently. Plasma triacylglycerols (TG) significantly
decreased with the activation of LPL and/or HTGL. Plasma total cholesterol (TC) and phospholipid (PL) levels decreased at
a low dose of PAF (0.2 μg/kg), but increased when higher doses were used. The PAF antagonist CV-6209 partially reversed the
PAF induced effects on HTGL, TC and PL.
Based on a paper presented at the Third International Conference on Platelet-Activating Factor and Structurally Related Alkyl
Ether Lipids, Tokyo, Japan, May 1989. 相似文献
5.
Yasunobu Hitaka Yoshito Tanaka Yutaka Tanaka Ken Ichiryu 《Artificial Life and Robotics》2009,14(4):494-497
A tripod parallel mechanism consists of three links of fixed length and a rigid platform, and these are connected by revolute
joints. The platform can achieve sixdegrees-of-freedom (6-DOF) motion by the coordinated movement of the bottom ends of the
three links on a horizontal plane. This mechanism has advantages over the more common six extendible parallel manipulators.
It has a much larger work space and a simple structure. In this article, we show that the vector analysis for this tripod
parallel mechanism and the derivation of the positions of the three bottom ends of the links in an arbitrary attitude of platform
can be found by inverse kinematics and the conditions of geometrical constraint. Then, by a numerical simulation, the trajectories
of the bottom ends of the three links are shown. 相似文献
6.
Tsusaka Y Suzuki H Yamashita K Kunieda H Tawara Y Ogasaka Y Uchibori Y Honda H Itoh M Awaki H Tsunemi H Hayashida K Nomoto S Wada M Miyata E Serlemitsos PJ Jalota L Soong Y 《Applied optics》1995,34(22):4848-4856
The x-ray properties of multinested thin-foil mirror x-ray telescopes (XRT's) on board ASCA, the Advanced Satellite for Cosmology and Astrophysics, were fully evaluated with an x-ray pencil beam.Scanning over the telescope aperture of 35 cm in diameter with an x-ray pencil beam, we found the effective area of a set of XRT's to be 325, 200, and 113 cm(2) at energies of 1.5, 4.5, and 8.0 keV, respectively. We derive the point-spread functions (PSF's) of the XRT's by measuring the image profile at the focal plane with an x-ray CCD. The PSF is found to exhibit a sharp core concentrated within 30 arcsec and a broad wing extended to 3 arcmin in half-power diameter. We also evaluate the contribution of stray light, which is caused by the single reflection of x rays by primary or secondary mirrors and by the backside reflection of the mirrors. To obtain the characteristics of the XRT in the energy region of 0.5-10.0 keV, incorporated with the measurements at discrete energies, we develop a ray-tracing method with the telescope design parameter, the PSF, and optical constants. In particular, we obtain the optical constants around the gold-atom M shell (Au-M) absorption-edge energies by measuring the reflectivity of our mirror sample, with monochromatized x-rays in the energy range of 2.0-3.5 keV from synchrotron radiation. Taking into account the PSF's and optical constants, we find that our ray-tracing program can reproduce all these XRT performances. 相似文献
7.
Particle-free silicon and nickel thin films were successfully fabricated by laser-ablating a melted section of their target surface, which gives a high evaporation pressure at the melting point. The influence of direct evaporation from a melted target was reduced negligibly by melting the target only locally with a focused electron beam (e-beam) and increasing the laser frequency. The silicon films fabricated by the present method, pulse laser deposition of a partially molten target, were able to firmly adhere to the substrates and withstood steel needle scratching, unlike e-beam-evaporated films. 相似文献
8.
Kurokawa M Masuda Y Noda M Usuda M Takeda S Hasegawa M Homma Y Sugano M 《Journal of oleo science》2008,57(1):35-45
In a placebo-controlled double-blind study, we examined the effects of dressing containing plant sterol (PS) on blood lipids and the safety in Japanese borderline or mildly hypercholesterolemic subjects. Fifty-nine subjects [total cholesterol (TC) concentration > or = 200 mg/dL] were randomly divided into two groups and were given daily 15 g of dressing containing 800 mg of PS [PS(+)-group] or without PS [PS(-)-group] for 12 weeks. Every 4 weeks, fasting blood was examined and subjective symptoms were analyzed. Serum TC, low-density lipoprotein cholesterol (LDL-C) and apolipoprotein B (ApoB) concentrations did not change in the PS(-)-group, while TC and ApoB significantly decreased in the PS(+)-group at 8 and 12 weeks and LDL-C at 4, 8 and 12 weeks. Moreover, serum TC, LDL-C and ApoB concentrations were significantly lower than those of PS(-)-group at 8 and 12 weeks. Other laboratory tests were all in normal ranges and no adverse events were observed. The results indicated that PS-containing dressing decreased serum TC, LDL-C and ApoB concentrations in borderline or mildly hypercholesterolemic subjects. It is therefore proved that the dressing containing PS is helpful in maintaining blood cholesterol level normal and hence, the health of Japanese. 相似文献
9.
N. Koizumi T. Hemmi K. Matsui H. Nakajima K. Okuno K. Kuno K. Nomoto 《Fusion Engineering and Design》2009,84(2-6):210-214
Research and trials by the Japan Atomic Energy Agency (JAEA) focus on the remaining technical issues in the ITER TF coil winding pack (WP) manufacturing process. Specific issues include the feasibility of automatically measuring conductor length during automatic winding with a high degree of accuracy (±0.02%) and a fabrication process to comply with the demanding tolerances (up to 1 mm distortion in flatness and 1.5 mm in-plane shrinkage) of the radial plate (RP) due to cover plate (CP) welding. The authors developed a new technique to measure conductor length very accurately by combining an ordinary encoder and a newly developed optical system. A simulation based on test results of CP welding using a RP mock-up indicates that a flatness of 1 mm is achievable, but the in-plane shrinkage of the RP is approximately 5 mm. One possible solution is to fabricate the RP larger than required to allow for in-plane shrinkage. Another solution is to reduce the thickness or length of the welding. The feasibility of these solutions to most of the major technical issues suggests that it is time for full qualification testing of the fabrication process in a dummy double-pancake trial. 相似文献
10.