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51.
利用分子动力学模拟的方法探究了乙酸乙酯与二溴甲烷组成的二元溶剂在298.15 K,1 atm下对ε-CL-20晶体形貌的影响。通过修正附着能模型(MAE)模型探究了溶剂-晶体相互作用,用分子动力学模拟预测了不同组成的乙酸乙酯/二溴甲烷混合溶剂中ε-CL-20的晶体形貌并与实验获得ε-CL-20的晶体形貌进行了对比。结果表明,实验获得的晶体形貌与模拟结果一致,且晶面粗糙度越大,溶剂-晶体相互作用越强。此外,还通过均方位移(MSD)分析了溶剂分子在不同晶面的扩散系数,探究了溶剂扩散速率对不同晶面的影响,并利用径向分布函数(RDF)分析了溶剂分子与晶体分子间相互作用的组成。 相似文献
52.
A new air-gap membrane distillation (AGMD) module for desalination with internal latent-heat-recovery which consisted of parallel hollow fiber membranes and heat exchange hollow fibers was successfully developed. The influences of feed flow rate, feed temperature and feed initial concentration on AGMD process were investigated. The vapor pressure polarization coefficient (η) was introduced to measure the reduction in the effective driving force for mass transfer with regard to the driving force imposed. Among all AGMD experiments, the maximum water vapor permeate flux (JD) of 5.30 kg/m2 h and the gained output ratio (GOR) of 5.70 were obtained. A theoretical model based on the mass and energy balances of the hot feed side was established to calculate the temperature and the local water vapor permeate flux distributions along the hollow fiber membrane, which showed that the temperature drop and local water vapor permeate flux drop were much larger at the upper part than those at the lower part of the membrane module in the hot feed side. 相似文献
53.
Runnan Zhang Yanlei Su Jinming Peng Xiaochen Fan Zhongyi Jiang Xueting Zhao Jiazhen Liu Yafei Li Jiaojiao Zhao 《Polymer》2014
In the present study, an in situ approach to pH and temperature responsive membranes is developed. The membrane matrix is formed through bulk polymerization and crosslinking of liquid monomer 2-hydroxyethyl methacrylate (HEMA) while the membrane pores are formed by the templating of inorganic particles. The functional monomers methacrylic acid (MAA) and N-isopropylacrylamide (NIPAAm) are incorporated into membrane casting solution in order to confer membranes with pH and temperature responsive properties. The poly(HEMA/MAA) membranes exhibit a reversible pH-dependent water flux, while the poly(HEMA/NIPAAm) membranes exhibit a reversible temperature-dependent water flux. The flux of the poly(HEMA/MAA) membrane increased by 70% when pH was decreased from 10.0 to 2.0, while the flux poly(HEMA/NIPAAm) membrane increased by 150% when temperature was increased from 20 to 45 °C. The protein adsorption and antifouling performance of the poly(HEMA/MAA) and poly(HEMA/NIPAAm) membranes also exhibit pH and temperature responsive properties. 相似文献
54.
Jing Zhao Xueting Zhao Zhongyi Jiang Zhen Li Xiaochen Fan Junao Zhu Hong Wu Yanlei Su Dong Yang Fusheng Pan Jiafu Shi 《Progress in Polymer Science》2014
By imitating the exceptional compositions, structures, formations and functions of biological or natural materials, a myriad of biomimetic and bioinspired membranes have been designed and prepared using cell membrane, lotus, mussel as representative prototypes and biomineralization, bioadhesion, self-assembly as major tools. These membranes have displayed fascinating properties and outstanding performances such as multiple interactions, hierarchical organizations, multiple selective transport mechanisms, superior stability/resistance and distinct adaptability. Meanwhile, these membranes have made tremendous contributions in coping with energy and water stress, environment threats. Biomimetics focuses on the basic science by fundamentally exploring the principles of biological systems, while bioinspiration focuses on the applied engineering by technologically implementing the principles from biological systems. Biomimetics and bioinspiration, as the complementary and interchangeable strategies for sustainable innovation and development of membrane technology, have great implications in exploring membrane materials and intensifying membrane processes. This review will present a brief overview on the prototypes, preparation, application as well as perspective of biomimetic and bioinspired membranes. 相似文献
55.
Shouwen Shi Dan Liu Dazhi Liu Patrick Tae Carrie Y. Gao Lei Yan Ke An Xu Chen 《Polymer Engineering and Science》2014,54(10):2215-2221
In this study, mechanical tensile stress–strain response and microstructure changes of proton exchange membranes (PEM) in immersed conditions are studied. The effects of water pretreatment and immersion time on stress–strain responses of Nafion®?212 membranes are discussed. It is found that in the water immersion it took 24 h for the membrane to reach saturation equilibrium. Compared with dry membrane, immersed Nafion membrane shows a lower stress level at 30°C, but a higher stress level at 70°C. In situ small angle neutron scattering (SANS) experiments show that with the increase of temperature and water uptake, domains of the membrane become ordered and stay stable at around 60°C. Based on the observation, the relationship between the microstructure and mechanical properties is explained. POLYM. ENG. SCI. 54:2215–2221, 2014. © 2013 Society of Plastics Engineers 相似文献
56.
Steven Ferguson Gary Morris Hongxun Hao Mark Barrett Brian Glennon 《Chemical Engineering Research and Design》2014
In this study, seed slurry from a single addition anti-solvent plug flow crystallization of benzoic acid was used to seed the equivalent batch cooling crystallization. The experimental conditions were carried out to simulate automated self-seeding. This involves withdrawal of solution from a batch crystallizer, which is then mixed with anti-solvent within a plug flow crystallizer, in order to generate a seed slurry which is fed directly back to the batch crystallizer. This seeding strategy allowed the final CSD of the batch crystallization to be controlled by variation of the crystal size from the plug flow seeding device at a constant seed loading. The ability to use unequal feed/anti-solvent inlet flowrates (in the Roughton vortex mixer) proved effective in controlling the batch CSD at 2% seed loading and constant feed composition. 相似文献
57.
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59.
《Energy》1988,13(11):823-831
The thermal performance of a solar pond operating under steady-state conditions is analysed theoretically for use in space heating in four diverse Turkish locations having widely different climates. The average pond temperature for each month is obtained for maximum heat extraction, with the thickness of the pond-insulating layers as a fixed parameter. For a fixed pond-insulating layer, the useful heat withdrawn during the month is calculated for these four locations. Space-heating loads and the solar heating fractions are estimated as functions of pond area for four different types of buildings. The necessary pond area is calculated for supplying the heat requirements for these prototype buildings. Finally, the economic feasibility of constructing solar-pond systems in Turkey is discussed. 相似文献
60.
《Synthetic Metals》1988,26(4):391-402
Thin polymeric nickel phthalocyanine (NiPc) and lead phthalocyanine (PbPc) films were prepared by the plasma-polymerization method. The phthalocyanine ring structure was largely undisturbed by this process. Lead phthalocyanine deposited in the high RF flux density regime produced some lead particles incorporated in the film, which were confirmed by electron diffraction patterns. In general the crystallite size of plasma-polymerized phthalocyanine films was much smaller than that for the chemical vapor deposited (CVD) phthalocyanine films. Plasma-polymerized phthalocyanine films deposited on interdigitated electrodes were evaluated as sensors for oxidizing and reducing gases. They showed fast response and excellent sensitivity to ppm level concentrations of NO2 in air. 相似文献