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81.
Jia‐Wei Li Yu‐Jing Chiu Chia‐Jui Chang Hung‐Chieh He Yi‐Hsuan Tu Kuan‐Ting Lin Yu‐Liang Lin Tzu‐Hsun Kao Hsun‐Hao Hsu Hsiao‐Fan Tseng Tien‐Chang Lu Jiun‐Tai Chen 《大分子材料与工程》2020,305(1)
Polyimides (PIs) possess excellent mechanical properties, thermal stability, and chemical resistance and can be converted to carbon materials by thermal carbonization. The preparation of carbon nanomaterials by carbonizing PI‐based nanomaterials, however, has been less studied. In this work, the fabrication of PI nanofibers is investigated using electrospinning and their transformation to carbon nanofibers. Poly(amic acid) carboxylate salts (PAASs) solutions are first electrospun to form PAAS nanofibers. After the imidization and carbonization processes, PI and carbon nanofibers can then be obtained, respectively. The Raman spectra reveal that the carbon nanofibers are partially graphitized by the carbonization process. The diameters of the PI nanofibers are observed to be smaller than those of the PAAS nanofibers because of the formation of the more densely packed structures after the imidization processes; the diameters of the carbon nanofibers remain similar to those of the PI nanofibers after the carbonization process. The thermal dissipation behaviors of the PI and carbon nanofibers are also examined. The infrared images indicate that the transfer rates of thermal energy for the carbon nanofibers are higher than those for the PI nanofibers, due to the better thermal conductivity of carbon caused by the covalent sp2 bonding between carbon atoms. 相似文献
82.
The effects of a low-modulus high-strain interleaf layer, introduced at the midplane, on unidirectional carbon/epoxy laminates
under flexural loading were investigated. The apparent energy-to-fail of the laminates increased significantly whereas the
maximum load decreased slightly upon interleaving. Real-time microscopic observations during static flexure tests at the lowest
deflection rate indicated a dramatic change of failure mode from the dominantly compressive fracture of the baseline laminate
to the dominantly tensile fracture process upon interleaving. Failure modes of interleaved and baseline laminates showed no
significant changes with test rate in the deflection rate range of 10−6 to 100 m/sec. 相似文献
83.
84.
核事故后果评价研究进展 总被引:3,自引:0,他引:3
回顾了国内外在核事故后果评价领域开展的概率风险评价、实时后果评价、事故后的后果评价技术与方法研究的发展历程,对后果评价研究在大气弥散模型的要求与发展、利用环境监测数据估算源项、食物链模型与事故季节性、剂量估算与防护措施、核与辐射突发事件(小尺度)响应、决策支持技术以及放射性物质长距离迁移问题等方面进行了讨论与分析。近年来,随着我国核能事业的迅猛发展,需要加强和发展核事故与突发事件的后果评价和应急响应技术。 相似文献
85.
86.
Use of Soy Protein and Microbial Transglutaminase as a Binder in Low-sodium Restructured Meats 总被引:1,自引:0,他引:1
ABSTRACT: Pork sticks were prepared by mixing pork chucks with various amounts of bisulfite-treated soy protein and microbial transglutaminase (MTGase) to evaluate the potential of using soy protein as meat binders. According to tensile strength, the favorable conditions for binding the restructured pork chunks were 5% soy protein containing 0.2% NaHSO3 and 20 unit MTGase/g, and the setting condition was 60 min at 40°C. The tensile strength and cooking yield of restructured pork sticks made with bisulfite-treated soy protein and MTGase were much higher than those of using salt, suggesting the high potential of using soy protein and MTGase as binders in products where NaCl reduction is desired. 相似文献
87.
基于SEA的潜射反舰导弹作战效能分析 总被引:1,自引:0,他引:1
在考虑作战双方的对抗以及战场环境影响的情况下,运用系统有效性分析(System Effec- tiveness Analysis,SEA)方法,将潜射反舰导弹的系统属性、作战环境和任务使命三要素结合起来,建立了潜射反舰导弹的效能评估模型,给出了基于战场环境下的动态作战效能评估方法,避免了以往静态效能评估和动态评估的局限性,使作战效能评估结果更加接近真实情况,对潜射反舰导弹作战效能的提高有一定的指导意义。 相似文献
88.
Li-Chung Wu Dong-Jiing Doong Chia Chuen Kao 《International journal of remote sensing》2013,34(5):1303-1318
In this study, a two-dimensional continuous wavelet transform is applied to quantify the non-homogeneity from remote-sensing wave images. Our study shows that the non-homogeneity index, which is proposed here, is capable of identifying the degree of non-homogeneity from the wave-field images. However, the influence from the edges of the wave-field image should be considered in analysis. The calculated results from the simulated wave fields and from the natural wave-field images reveal that the non-homogeneity index is influenced by the bathymetry inside the area of the ocean-wave image. It conforms to the character of the natural wave non-homogeneity. After discussing the wave characteristics from the wave-field image with a high non-homogeneity index, an inhomogeneous algorithm is recommended for obtaining accurate and reasonable wave results from the wave image. 相似文献
89.
90.
Tse-Chang Li Ming Tsung Kao Jen Fin Lin 《Journal of Materials Science: Materials in Electronics》2014,25(10):4425-4433
Al/glass specimens are prepared following the orthogonal table of five-level six-factorial (L25(56)) design. The governing factors for the preparation of the specimens are deposition conditions, annealing temperature and annealing time. Defects, including hillocks and nanovoids, are found to be created during the annealing process. The threshold value of the annealing stress (σ an ) required for the incipience of hillocks is thus determined. The stress change parameter, σ f –σ an (σ f :internal stress after annealing), is a positive value that increases linearly with σ an . The density of hillocks increases linearly with (σ f –σ an ) when the value of the stress change parameter is beyond the critical value (130 MPa). Nanovoids are produced even in specimens without hillocks. The wedge angle that forms in a specimen after wet etching linearly decreases with decreasing (σ f –σ an ). A high wedge angle lowers the hillock density at the wedge slope. The electrical resistance of the gate layer linearly increases with increasing product value (R*) of the mean size (area) and the density of nanovoids. R* increases nonlinearly with increasing (σ f –σ an ). 相似文献