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81.
新的一代光刻设备朝着两个方向发展 ,一是趋向于大数值孔径、短波长 ;另一方面国际上正在寻求适应二十一世纪、小于 0 .1 5微米线宽的软 X射线投影光刻技术 ,预计成为下世纪制造千兆位以上超大规模集成电路的主要设备。软 X射线光刻及其应用研究是目前国际上非常活跃的高技术领域。把软 X射线光刻列为重要发展项目。本文摘要综述德国、美国、日本、俄罗斯等国近年来在软 X射线光刻关键单元技术及整机研究和发展方面的概况、预计下世纪初美国和日本将有软 X射线投影光刻机投入工艺生产线 相似文献
82.
The condition of the surfaces is of crucial importance for the deuterium permeation through materials. In this work a study of the surface constants for the adsorption (σk1) and release (σk2) of deuterium under different surface conditions on the martensitic steel DIN 1.4914 (MANET) has been carried out. The growth of an oxide surface layer (Cr2O3) of about 25–30 nm in a MANET sample, heat treated in an oxidizing environment, compared to the bare MANET that have a ‘natural' oxide of about 5 nm has provoked a reduction of both the permeation rate and the recombination coefficient (about 3 orders of magnitude). In addition, the permeation governing process has changed from diffusion-limited to surface-limited. The measurements of the permeation rate of deuterium were performed by a gas-phase permeation technique over the temperature range 574–746 K and for deuterium driving pressures in the range from 3 to 105 Pa. 相似文献
83.
Microwave irradiation processing (MIP) was considered as a potential method to synthesize perovskite-type oxides rapidly, cleanly and energy-efficiently. In this paper, La0.7Sr0.3MnO3+λ, a kind of promising catalyst for automobile exhaust purification, was successfully prepared by MIP in not more than 5 min. The sol–gel method was also used for comparison. All the samples were evaluated by catalytic activity tests in the simulated exhaust and characterized by XRD, BET, TEM and XRF analyses. The results showed that the integrated perovskite-type phase and uniform particle size were obtained in the microwave-treated samples. And those ones exhibited a better oxidation activity under slightly oxygen-rich condition than that by sol–gel method, which may be related to more A-site cation vacancies and larger bulk oxygen content generated in MIP. Possible formation mechanism of perovskites in MIP was also discussed. 相似文献
84.
85.
Teruya Tanaka Junichi. H. Kaneko Yoshimi Kasugai Masaki Katagiri Hiroshi Takeuchi Takeo Nishitani Toshiyuki Iida 《Diamond and Related Materials》2005,14(11-12):2031
Radiation tolerance of a type IIa synthetic diamond detector was examined from irradiation of mono-energetic 14 MeV neutrons. Measurements of I–V (current–voltage) characteristics and energy spectrum for 5.486 MeV alpha particles were performed after neutron irradiation. In the I–V characteristics measurement, enhancement of rectification was observed after neutron irradiation of up to 2.0 × 1012 n/cm2. Concurrently with the enhancement of rectification, significant decrease in signal amplitude was observed in energy spectrum measurement for alpha particles. It is considered that these changes were due to increase in the concentration of defects acting as shallow energy levels in the forbidden band. For neutron irradiation of higher than 1.6 × 1013 n/cm2, weakening of the rectification characteristics and recovery of the signal amplitude were observed. These changes imply that deep energy levels, which were also considered to be introduced by defects, were dominant and weakened the effects of the shallow energy levels. Increase in the concentration of the deep trapping levels resulted in gradual decrease of the signal amplitude and degradation in the energy resolution. The peak for the alpha particles was obtained up to 5.5 × 1013 n/cm2. 相似文献
86.
We have made a study of the chemical composition, the electrical, the optical and the structural properties of polycrystalline CuInS2 thin films prepared by spray pyrolysis to be used for thin film solar cells. These films were deposited starting from aqueous solutions with different chemical compositions ([Cu]/[In] and [S]/[Cu] ratios) and at different substrate temperatures. In all cases, the material is p-type with grains preferentially oriented in the (112) direction of the sphalerite structure. The electro-optical properties show a very strong dependence on the [Cu]/[In] ratio in the solution. Films with copper excess have smaller resistivity and better crystallinity than those which are stoichiometric or have indium excess. The results obtained in this work show the possibility of having CuInS2 thin films with a wide range of resistivity, a fact that could be important for making solar cells based on this material. 相似文献
87.
氯丁橡胶的溶液接枝反应研究 总被引:3,自引:1,他引:2
本文研究了引发剂过氧化苯甲酰的用量对CR接技MMA-AA反应的单体转化率、接枝率及接枝胶的粘度、剥离强度等的影响,并用红外光谱和元素和元素分析对反应产物进行了表征.结果表明,体系中存在接枝、降解、交联三种反应,在不同的配方和工艺条件下,三种反应的反应程度不同. 相似文献
88.
An FTIR experiment especially designed to study the growth of an organosilane layer at the interface between a solution and a flat silica surface is presented. High sensitivity is achieved by using the attenuated total reflection (ATR) technique in a liquid flow cell. The ATR crystal, either silicon or germanium, is covered with a very thin silica layer. Chemical reactions of a mono-and a di-hydrolyzable silane with the silica substrate have been investigated. The grafting of a submonolayer of the first reagent has been monitored by following the C-H and SiO-H vibrations. The density of grafted molecules has been estimated and information on the nature of the chemical bonding has been achieved. Evidence for the chain-polymerization of the dihydrolyzable silane at the substrate/solution interface has been inferred from the appearance of a Si-O-Si absorption band. 相似文献
89.
40Cr钢试样经不同热处理后在空气中用CO2连续激光束进行辐照,以穆斯堡尔谱学研究试样在辐照后的组织结构变化。试验结果表明,调质预处理后再进行激光辐照的试样,不仅残作产奥氏体含量较低,而且其中碳的含量最低。 相似文献
90.
高能粒子辐照对零膨胀微晶玻璃光学性质和面形光学稳定性的影响 总被引:2,自引:1,他引:1
研究了高能电子,高能质子对VO2微晶玻璃辐照前后光性质和面形光学稳定性的影响,研究结果表明,高能电子辐照能引起微晶玻璃面形明显变化,且使VO2微晶玻璃强烈着色。高能质子辐照没引起面形明显变化,高能质子辐照对反射光谱特性没有影响。 相似文献