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81.
中酸性小岩体的内部及附近的围岩中常形成与岩浆岩体有关的大型、超大型矿床,已成为找矿工作的一个重点方向。由于地质工作程度的限制,中酸性小岩体易被遗漏,严重制约了该类型矿化的发现。在新疆西准噶尔达尔布特断裂带下盘加甫沙尔苏地区找矿工作中,通过综合分析,提出了以遥感手段为主导的中酸性小岩体型矿化找矿模型:利用ASTER数据,通过图像增强处理、图像解译识别中酸性小岩体并提取蚀变遥感异常,结合地质、化探信息综合分析后确定重点检查区域。野外检查发现了加甫沙尔苏斑岩型钼矿化点,证实了该方法的有效性。该方法可以为西部地区中酸性小岩体型矿产资源勘查提供借鉴。 相似文献
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钮丽 《网络安全技术与应用》2014,(10):132-132
随着时代的发展,科技信息的进步对人才的所具备的信息处理的能力提出了很高的要求,计算机基础课程在各类院校都是一门非常重要的公共基础课程,为了更好的让学生掌握好这门课程,计算机教学方法是非常有必要创新的,本文主要介绍案例教学法在计算机基础教学中的优势及其存在的问题等进行研究. 相似文献
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The effects of homopolymer and copolymer compositions and structures in styrene/n-butyl acrylate (Sty/BA) latices on sodium dioctyl sulfosuccinate (SDOSS) surfactant mobility and its preferential concentration at the film–air (F–A) and film–substrate (F–S) interfaces were examined using attenuated total reflectance Fourier transform infrared (ATR FTIR) spectroscopy. It appears that the SDOSS concentration at the F–S interface is highest when the Sty/BA feed ratio is 50/50, and the excess of Sty results in migration of SDOSS surfactant to the F–A interface. This behavior is attributed to the increased glass transition temperature and diminished compatibility between surfactant molecules and copolymer latex. This study also shows that the primary factors that influence exudation to either F–A or F–S interfaces are surface tension of the substrate, glass transition temperature, water flux during coalescence, and compatibility between latex components. © 1995 John Wiley & Sons, Inc. 相似文献
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We have found that not only block copolymers but also ionomers can self-assemble in a selective solvent to form surfactant-free nanoparticles. The self-assembly can be induced by chemical reaction, polymer-polymer complexation, and microphase inversion in addition to the temperature. A recently developed microwave method for the preparation of uniform surfactant-free polymeric nanoparticles is also reviewed. Our results have revealed that for a given dispersion, the particle surface area occupied per stabilizer (surfactant, polymer chains, and ionic groups) is close to a constant. 相似文献
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Blends of statistical copolymers containing ethylene/hexene (PEH) and ethylene/butene (PEB) exhibited the behavior of upper critical solution temperature (UCST). The interplay between the early and intermediate stage liquid-liquid phase separation (LLPS) and crystallization of the PEH/PEB 50/50 blend was studied by time-resolved simultaneous small-angle X-ray scattering (SAXS) and wide-angle X-ray diffraction (WAXD) techniques. Samples were treated by two different quench procedures: in single quench, the sample was directly quenched from 160 °C to isothermal crystallization temperature of 114 °C; while in double quench, the sample was firstly quenched to 130 °C for 20 min annealing, where LLPS occurred, and then to 114 °C. It was found that in the early stage of crystallization, the integrated values of Iq2 and crystallinity, Xc, in the double quench procedure were consistently higher than those in the single quench procedure, which could be attributed to accelerated nucleation induced by enhanced concentration fluctuations and interfacial tension. In the late stage of crystallization, some morphological parameters were found to crossover and then reverse, which could be explained by retardation of lamellar growth due to phase separation formed during the double quench procedure. This phenomenon was also confirmed by DSC measurements in blends of different compositions at varying isothermal crystallization temperatures. The crystal lamellar thickness determined by SAXS showed a good agreement with TEM observation. Results indicated that the early stage LLPS in the PEH/PEB blend prior to crystallization indeed dictated the resulting lamellar structures, including the average size of lamellar stack and the stack distribution. There seemed to be little variation of lamellar thickness and long period between the two quenching procedures (i.e., single quench versus double quench). 相似文献
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A series of new polyamides 3a–d containing aryl-azo, ether and sulfone groups in the main chain were synthesized from bis[4-(4-aminophenoxy)phenyl sulfone]
1 and several azo aromatic diacyl chlorides 2a–d by the low temperature solution polycondensation technique. FTIR spectroscopy, nuclear magnetic resonance (NMR) and elemental
analyses confirmed the structure of these polymers. Owing to the aryl and amide groups in the main chain, these polymers exhibit
photochromic properties as well as excellent thermal stabilities. The transition temperatures (T
g) are between 242 and 265 °C, and the char yields at 800 °C in nitrogen atmosphere were above 39%. Based on incorporation
of flexible ether linkages and polar sulfone groups, the polyamides show desirable solubility in organic solvents such as
DMAc, N,N-dimethylformamide (DMF), N-methyl-2-pyrroidinone (NMP) and dimethylsulfoxide (DMSO). And it is exemplified that
polyamide containing 2 and 2′ substitutes performed better solubility.
Funded by the National Natural Science Foundation of China (No. 50572081) 相似文献
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