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72.
A regularized optimality system for state-constrained optimal control problems is introduced and semi-smooth Newton methods for its solution are analyzed. Convergence of the regularized problems is proved. Numerical tests confirm the theoretical results and demonstrate the efficiency of the proposed methodology. 相似文献
73.
74.
E Kojima K Naito M Iwai Y Hirose K Isobe K Takano 《Canadian Metallurgical Quarterly》1997,36(7):528-531
A 37-year-old woman underwent an emergency operation at our hospital because of severe abdominal pain and ileus. Most of her small intestine and ascending colon were observed to have become necrotic due to occlusion of her superior mesenteric artery (SMA). Pathological findings of the resected intestine revealed that her SMA was completely thrombosed 2 cm distal from its origin with smooth muscle proliferation. Post-surgical blood analysis of her pre-operative serum was positive for lupus anticoagulant and antinuclear antibodies. She noticed vaginal bleeding due to missed abortion on the 31st day after the operation. We diagnosed her acute abdominal pain to be that of antiphospholipid syndrome associated with her pregnancy. 相似文献
75.
Zhengxin Liu Atsushi Masuda Takehiko Nagai Takashi Miyazaki Miwako Takano Masahiro Takano Haruyuki Yoshigahara Kazutoshi Sakai Koichi Asai Michio Kondo 《Solar Energy Materials & Solar Cells》2007,91(19):1805-1810
Spherical Si solar cell, which is made up of Si spheres with a diameter of approximately 1.0 mm, is expected to be a promising candidate for low consumption of Si feedstock and simple process technology. This paper describes the formation process and the structure of a concentrator module in detail. The concentrator lens was formed by casting with ultraviolet light hardening resin. The concentration ratio was 4.4 times and the pitch between the spheres was 2.0 mm. By this module design, it was possible to realize a consumption of the Si feedstock of about 3.0 g/W. Conversion efficiencies of 11.3% from single-sphere cell, 8.5% from a 23-spheres module and 5.2% from a 105-spheres module under AM1.5, 100 mW/cm2 illumination were achieved. 相似文献
76.
Masaaki Hirayama Noriyuki Sonoyama Takeshi Abe Machiko Minoura Masumi Ito Daisuke Mori Atsuo Yamada Ryoji Kanno Takahito Terashima Mikio Takano Kazuhisa Tamura Jun’ichiro Mizuki 《Journal of power sources》2007
A new experimental technique was developed for detecting structure changes at electrode/electrolyte interface of lithium cell using X-ray reflectometry and two-dimensional model electrodes with a restricted lattice-plane. The electrodes were constructed with an epitaxial film of LiCoO2 synthesized by pulsed laser deposition method. The orientation of the epitaxial film depends on the substrate plane; the 2D layer of LiCoO2 is parallel to the SrTiO3 (1 1 1) substrate ((0 0 3)LiCoO2//(1 1 1)SrTiO3), while the 2D layer is perpendicular to the SrTiO3 (1 1 0) substrate ((1 1 0)LiCoO2//(1 1 0)SrTiO3). The anisotropic properties were confirmed by electrochemical measurements. Ex situ X-ray reflectivity measurements indicated that the impurity layer existed on the as-grown LiCoO2 was dissolved and a new SEI layer with lower density was formed after soaking into the electrolyte. In situ X-ray reflectivity measurements indicated that the surface roughness of the intercalation (1 1 0) plane increased with applying voltages, while no significant changes in surface morphology were observed for the intercalation non-active (0 0 3) plane during the pristine stage of the charge–discharge process. 相似文献
77.
Kobayashi M Ohtsuka K Tamura Y Tomizawa S Kamijo K Iwakoshi K Kageyama Y Nagayama T Takano I 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(2):121-129
A survey of pesticide residues in 595 imported frozen products on the Tokyo market from April 1989 to March 2008 was carried out. Forty three kinds of pesticides, including organophosphorus, organochlorine, carbamate, pyrethroid and others, were detected between levels of trace (below 0.01 ppm) and 4.6 ppm from 162 samples. Chlorpyrifos, cypermethrin and omethoate were frequently detected in green vegetables (komatsuna leaf and spinach), cypermethrin and methamidophos were detected in pods and seeds (green soybean and string pea), chlorpropham (CIPC) was detected in potato, and captan and carbaryl were detected in berries (blueberry, raspberry and strawberry). The hydrophilic pesticide methamidophos was detected in flesh of lychee. Residue levels of these pesticides were calculated as between less than 0.5% and 30% of their ADI values according to the daily intake of frozen products. Therefore, these frozen products should be safe when they were eaten in customary amounts. 相似文献
78.
Y Qiu P Ping XL Tang S Manchikalapudi A Rizvi J Zhang H Takano WJ Wu S Teschner R Bolli 《Canadian Metallurgical Quarterly》1998,101(10):2182-2198
Brief ischemic episodes confer marked protection against myocardial stunning 1-3 d later (late preconditioning [PC] against stunning). The mechanism of this powerful protective effect is poorly understood. Although protein kinase C (PKC) has been implicated in PC against infarction, it is unknown whether it triggers late PC against stunning. In addition, the entire PKC hypothesis of ischemic PC remains controversial, possibly because the effects of PKC inhibitors on PC protection have not been correlated with their effects on PKC activity and/or translocation in vivo. Thus, conscious rabbits underwent a sequence of six 4-min coronary occlusion (O)/4-min reperfusion (R) cycles for three consecutive days (days 1, 2, and 3). In the control group (group I, n = 7), the recovery of systolic wall thickening after the six O/R cycles was markedly improved on days 2 and 3 compared with day 1, indicating the development of late PC against stunning. Administration of the PKC inhibitor chelerythrine at a dose of 5 mg/kg before the first O on day 1 (group II, n = 10) abrogated the late PC effect against stunning, whereas a 10-fold lower dose (0.5 mg/kg; group III, n = 7) did not. Administration of 5 mg/kg of chelerythrine 10 min after the sixth reperfusion on day 1 (group IV, n = 6) failed to block late PC against stunning. When rabbits were given 5 mg/kg of chelerythrine in the absence of O/R (group V, n = 5), the severity of myocardial stunning 24 h later was not modified. Pretreatment with phorbol 12-myristate 13-acetate (4 microg/kg) on day 1 without ischemia (group VI, n = 11) induced late PC against stunning on day 2 and the magnitude of this effect was equivalent to that observed after ischemic PC. In vehicle-treated rabbits (group VIII, n = 5), the six O/R cycles caused translocation of PKC isoforms epsilon and eta from the cytosolic to the particulate fraction without significant changes in total PKC activity, in the subcellular distribution of total PKC activity, or in the subcellular distribution of the alpha, beta1, beta2, gamma, delta, zeta, iota, lambda, and mu isoforms. The higher dose of chelerythrine (5 mg/kg; group X, n = 5) prevented the translocation of both PKC epsilon and eta induced by ischemic PC, whereas the lower dose (0.5 mg/kg; group XI, n = 5) prevented the translocation of PKC eta but not that of epsilon, indicating that the activation of epsilon is necessary for late PC to occur whereas that of eta is not. To our knowledge, this is the first demonstration that a PKC inhibitor actually prevents the translocation of PKC induced by ischemic PC in vivo, and that this inhibition of PKC translocation results in loss of PC protection. Taken together, the results demonstrate that the mechanism of late PC against myocardial stunning in conscious rabbits involves a PKC-mediated signaling pathway, and implicate epsilon as the specific PKC isoform responsible for the development of this cardioprotective phenomenon. 相似文献
79.
Yoshinori Dobashi Kazufumi Kaneda Hideki Nakatani Hideo Yamashita Tomoyuki Nishita 《Computer Graphics Forum》1995,14(3):229-240
When designing interior lighting effects, it is desirable to compare a variety of lighting designs involving different lighting devices and directions of light. It is, however, time-consuming to generate images with many different lighting parameters, taking interreflection into account, because all luminances must be calculated and recalculated. This makes it difficult to design lighting effects interactively. To address this problem, this paper proposes a method of quickly generating images of a given scene illustrating an interreflective environment illuminated by sources with arbitrary luminous intensity distributions. In the proposed method, the luminous intensity ditribution is expressed with basis functions. The proposed method uses a series of spherical harmonic functions as basis functions, and calculates in advance each intensity on surfaces lit by the light sources whose luminous intensity distribution are the same as the spherical harmonic functions. The proposed method makes it possible to generate images so quickly that we can change the luminous intensity distribution interactively. Combining the proposed method with an interactive walk-through that employs intensity mapping, an interactive system for lighting design is implemented. The usefulness of the proposed method is demonstrated by its application to interactive lighting design, where many images are generated by altering lighting devices and/or direction of light. 相似文献
80.
H Aida K Takakuwa H Nagata I Tsuneki M Takano S Tsuji T Takahashi T Sonoda M Hatae K Takahashi K Hasegawa H Mizunuma N Toyoda H Kamata Y Torii N Saito K Tanaka M Yakushiji T Araki K Tanaka 《Canadian Metallurgical Quarterly》1998,4(1):235-240
BACKGROUND: Stentless aortic xenografts are an important addition to the range of prosthetic valves. So far their use has been restricted to a limited number of study centers. This report summarizes the principal findings from the Second International Symposium on Stentless Bioprostheses. Attention is focused on the Toronto SPV and Freestyle valves recently approved by the United States Food and Drug Administration. METHODS: Stentless xenografts are used predominantly in elderly patients with aortic stenosis. Implant techniques are more complex than for stented valves, as reflected by longer ischemic and cardiopulmonary bypass times. The valves have been subjected to detailed serial echocardiographic assessment and clinical follow-up. RESULTS: The hemodynamic characteristics resemble those of the aortic homograft. There is a progressive increase in effective orifice area and decrease in transvalvular pressure gradients with time. Left ventricular mass index and wall thickness normalize between 6 and 12 months postoperatively. Left ventricular remodeling is accompanied by improved symptomatic status and a low incidence of valve-related complications. Limited comparative studies suggest important benefits over stented xenografts. Improved hemodynamics may translate into better bioprosthetic durability. CONCLUSIONS: Reproducible and reliable implant methods should be taught carefully, but the hemodynamic advantages are substantial. Stentless xenografts are ideal for the elderly patient with aortic stenosis. 相似文献