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51.
俄罗斯有150多家酒精工厂,工厂平均年产量1万t左右,主要原料为大麦、小麦、玉米和黑麦等。俄罗斯食品生物技术科学研究所是俄罗斯研究酒精生产、酶制剂和酵母的权威机构,该所开发的酒精生产工艺在世界上处于领先地位。其主要技术成果包括:65~80℃低温蒸煮,双酶法糖化,28~38℃中高温快速浓醪发酵,蒸馏废水回用等项技术;其中机械涡流均质是一项有效的节能技术,可节约能耗20%左右。 相似文献
52.
Hryhorii P. Parkhomenko Mykhailo M. Solovan Sanjay Sahare Andriy I. Mostovyi Damir Aidarkhanov Nora Schopp Taras Kovaliuk Marat Kaikanov Annie Ng Viktor V. Brus 《Advanced functional materials》2024,34(10):2310404
This work investigates the radiation resistance of high-performance multi-component perovskite solar cells (PSCs) for the first time under extreme short-pulse proton irradiation conditions. The devices are subjected to high-intensity 170 keV pulsed (150 ns) proton irradiation, with a fluence of up to 1013 p cm−2, corresponding to ≈30 years of operation at low Earth orbit. A complex material characterization of the perovskite active layer and device physics analysis of the PSCs before and after short-pulse proton irradiation is conducted. The obtained results indicate that the photovoltaic performance of the solar cells experiences a slight deterioration up to 20 % and 50 % following the low 2 × 1012 p cm−2 and high 1 × 1013 p cm−2 proton fluences, respectively, due to increased non-radiative recombination losses. The findings reveal that multi-component PSCs are immune even to extreme high-intense short-pulse proton irradiation, which exceeds harsh space conditions, including intense coronal ejection events usually associated with solar flares. 相似文献
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Mikhail Yu. Sinev Yurii P. Tulenin Olga V. Kalashnikova Viktor Yu. Bychkov Vladimir N. Korchak 《Catalysis Today》1996,32(1-4):157-162
The analysis of methane oxidation in a wide range of pressures (0.05–10 atm) demonstrates that the efficiency of CH3 radicals recombination is of great importance for high selectivity of C2 hydrocarbons formation. The relative efficiency of different “colliders” assisting the stabilization of exited C2H*6 molecules increases in the series: solid surface> Ar> He. The increase of the overall reaction rate upon increasing pressure of the inert gases in the case of catalysts having a higher surface area and more developed pore structure is likely due to the contribution of the surface-induced chain reaction in the volume of pores. 相似文献
57.
Lars Håkanson Alexander Ostapenia Arkady Parparov K. David Hambright Viktor V. Boulion 《Lakes & Reservoirs: Research and Management》2003,8(2):141-155
The aim of this paper is twofold: to present and discuss practically useful management criteria from different perspectives of lake management (fishery, recreation, conservation, monitoring of water quality and use of water for irrigation and drinking), and to put these criteria into the context of a holistic lake ecosystem model, LakeWeb, which accounts for production, biomasses, predation and abiotic/biotic feedbacks related to nine key functional groups of organisms constituting the lake ecosystem. These are phytoplankton, benthic algae, macrophytes, bacterioplankton, herbivorous zooplankton, predatory zooplankton, zoobenthos, prey fish and predatory fish. The LakeWeb model also includes a mass‐balance model for phosphorus and calculates bio‐uptake and retention of phosphorus in these groups of organisms. It also includes submodels for the depth of the photic zone and lake temperature. The LakeWeb model is driven by few and readily accessible driving variables and it has been extensively tested and shown to capture fundamental lake foodweb interactions very well, which should lend credibility to the scenarios discussed in this paper regarding the conditions in Lake Batorino, Belarus. The LakeWeb model offers a tool to address important, often very complex, scientific problems in a realistic manner. The first scenario describes the changes after 1990 when there was a drastic reduction in the use of fertilizers in agriculture because of political changes and the corresponding changes in lake characteristics and foodweb structures utilizing the given management criteria. The second scenario describes, for comparative purposes, the probable alterations in the lake foodweb related to global climatic changes; in this case, warming and increased temperature variations. This study indicates that there are several similarities between eutrophication and increases in temperatures, which are discussed in this paper along with the mechanistic reasons related to such changes by using a set of general management criteria. 相似文献
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Oleg I. Belous Anatoliy I. Fisun Anatoliy A. Kirilenko Viktor K. Korneenkov Vladimir S. Miroshnichenko 《Journal of Infrared, Millimeter and Terahertz Waves》1997,18(2):445-461
Theoretical and experimental results of an investigation into a new resonant system have been obtained. This system is named the sphere-corner-echelette open resonator (SCEOR) due to the employment of a mirror that was formed by two echelettes at the angles of 45° to the resonator axis. It turns ont that this resonator is excited on the specific modes not unique to others oscillating systems. There are presented the results of the experimental research of the orotron oscillator with the SCEOR. The spectrum of this device contains only the fundamental modes such as theT E M 006,T E M 007,T E M 008. The efficiency of the orotron is improved, when all other factors are the same the orotron with a much used sphere-cylindrical open resonator. 相似文献
60.
Viktor Tsepelin Harry Alles Alexei Babkin Reyer Jochemsen Alexander Ya. Parshin Igor A. Todoshchenko 《Journal of Low Temperature Physics》2002,129(5-6):489-530
The shapes as well as the growth and melting properties of bcc-3He single crystals have been investigated with a low temperature Fabry-Pérot interferometer. Eleven types of facets were clearly identified during slow crystal growth at the temperature of 0.55 mK, where the solid is in the antiferromagnetically ordered u2d2 phase. The growth rates of the individual facets have been measured and the results indicate significant growth anisotropy. The observed linear dependence of the growth velocity on the driving force shows that facets grow due to the presence of screw dislocations, while the step velocity is limited by the spin wave velocity due to the strong interaction of the moving step with magnons in the solid. The measured growth rates of the facets and the assumed growth mechanism gave us the unique opportunity to obtain the step free energies for ten different types of facets observed during a single growth sequence. The dependence of the free energy of the step on the step height is compared with predictions of the weak- and strong-coupling models. Our results suggest that 3He crystals have rather strong coupling of the liquid/solid interface to the crystal lattice and that the step-step interactions are of elastic origin. 相似文献