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51.
Sputtering of Zn(O,S) from ZnO/ZnS compound targets has been proven to be a promising buffer layer process for Cd‐free CIGS modules due to easy in‐line integration, low cost and high efficiency on lab scale. In this publication, we report on successful upscaling of the lab process to pilot production. A record aperture efficiency of 13.2% has been reached on a 50 × 120 cm2 sized module. Neither a non‐doped ZnO layer nor additional annealing steps are required. Moreover, this very reproducible process yields a standard deviation comparable with that of the CdS base line. In contrast to lab experiments, strong performance gain after light soaking has been observed. The light‐soak‐induced power increase depends on the preparation of the window layer. Accelerated aging tests show high stability of module power. This is confirmed by outdoor testing for 20 months. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   
52.
Cd(S1-xSex) pigments (red to yellow) were synthesized by precipitate-hydrothermal method.The structure,morphology and hue of the powder were characterized by X-ray diffractometry (XRD),scanning electron microscopy (SEM),energy dispersive X-ray spectroscopy (EDAX) and CIE chromaticity.The optimum synthesis conditions were obtained and reaction mechanism was further analyzed as well.The results show that molar ratio of S to Se,pH value and hydrothermal reaction conditions have great effects on the hues of the pigments.Pigments with vivid hues are obtained under the conditions that pH value is about 13.0,hydrothermal reaction condition is at 140 ℃ for 4 h or at 160 ℃ for 6 h.The reaction mechanism is that Se2- of Cd(S1-xSex)substitutes S2- of CdS and then forms a continuous solid solution.  相似文献   
53.
用分析电子显微镜观察了碲镉汞晶体的显微结构。发现在大剂量电子辐射下,显微结构有较强的损伤。进一步用 X线能谱分析和高分辨电子显微术研究表明,大剂量电子辐射引起了碲镉汞晶体的超结构、叠栅、无序化和 Hg 含量减少。  相似文献   
54.
Changes in the composition and crystalline structure of gasochromic tungsten oxide films resulting from the incorporation of hydrogen were investigated; the oxide films were prepared by reactive RF magnetron sputtering on SiO2 and glassy carbon substrates simultaneously. X-ray diffraction analysis of the deposited films at 600 °C showed a uniaxial oriented structure in the (0 1 0) plane of monoclinic WO3 for both substrates. The elastic recoil detection analysis (ERDA) and Rutherford backscattering spectroscopy (RBS) for the films on glassy carbon revealed that the hydrogen impurity was uniformly distributed up to a concentration of 0.24 H/W. The Pd-coated films on SiO2 turned blue when they were exposed to a mixture of Ar and 5% H2 gases. When the sample became colored, the hydrogen concentration in the film increased to 0.47 H/W and the crystalline structure of the film changed from monoclinic to tetragonal. These results indicated that the gasochromic coloration of the tungsten oxide films coincided with incorporation of hydrogen atoms into the crystalline lattice, corresponding to the formation of hydrogen tungsten bronze (HxWO3).  相似文献   
55.
The present investigation reports the possibility of using Acacia saligna and Delbergia sisso pods to remove Cd(II) from aquatic systems in the form of calcium alginate modified immobilized composite beads (CAM-ASPCB and CAM-DSPCB). Batch and fixed bed column studies were carried out under various process affecting parameters. Maximum metal removal efficiency of 92% by CAM-ASPCB and 85% by CAM-DSPCB was observed under optimized conditions. Pseudo-second-order kinetic model, intra-particle diffusion, and Freundlich isotherm were found fitted well. The regeneration of the sorbents were found effectively high showing up to 10 cycles for simulated solution and up to 3 cycles for industrial effluent.  相似文献   
56.
通过对庐山区农村饮用水进行抽样测定了重金属Pb、Cd的含量,分析重金属Pb、Cd的污染情况。选取有代表性的水样28份,采用石墨炉原子吸收光谱法(GF-AAS)测定饮用其中Pb、Cd的含量。结果表明:28份水样中所含Pb量为(0.2386±0.4124)μg/L,Cd量为(0.0984±0.1456)μg/L。根据《生活饮用水卫生标准》(GB/T5750-2006),Pb限度为10μg/L,Cd限度为5μg/L,28份样本所测的重金属均在其限度范围内,表明庐山区农村饮用水没有重金属Pb、Cd的污染。  相似文献   
57.
The use of chemically modified silica gel N-(1-carboxy-6-hydroxy) benzylidenepropylamine (SiG-CHBPA), ion exchanger for removal and preconcentration of Cr, Mn, Fe, Co, Ni, Cu, Zn, Cd and Pb in natural water samples collected from River Nile, Mediterranean Sea and other locations followed by their consecutive AAS determination was described. The effects on the percentage of recovered metal ions including mass change of ion exchanger, stirring time, pH of sample solutions and eluent concentration were studied. The distribution coefficient Kd, ml g− 1 and the percentage concentration of the studied metal ions on the ion exchanger at equilibrium, CM,eqm ,% (Recovery, %) were studied as a function of experimental parameters. The logarithmic values of the distribution coefficients, log Kd are 3-6.3. The interfering effects of some foreign ions on the removal, preconcentration and determination of the investigated metal ions were described. The metal-chelates formed between the ion exchanger and the studied metal ions were characterized by IR (absorption and reflectance), UV spectrometry, potentiometric titration and thermal analysis (TG and DTG). The reliability of the present method was confirmed by the comparison with a standard solvent extraction method. The present method is simple and rapidly applicable for the determination of the studied metal ions, ng ml− 1 in different natural water samples.  相似文献   
58.
Field studies were conducted over 3 years at several locations in Alberta and Manitoba, Canada to evaluate the impact of phosphate fertiliser containing varying concentrations of Cd on grain yield and P, Zn and Cd concentration in durum wheat grain. The effect of a seed treatment with Penicillium bilaii, a phosphate‐solubilising fungus, was also examined. P bilaii had little effect on crop yield, nutrient concentration or the concentration of Cd in the grain under the conditions of this study. Fertilisation with monoammonium phosphate consistently increased Cd concentration and Cd/Zn ratio and decreased Zn concentration in durum wheat. Increases in Cd concentration in durum wheat were unrelated to Cd concentration in the fertiliser, although the concentration of Cd in the fertiliser sources varied from 0.2 to 186.0 µg g?1. Increased Cd concentration with phosphate application may be related to high ionic strength, reduced pH and enhanced root proliferation in the microregion around the fertiliser granules. Enhanced root development in response to phosphate fertilisation may increase the accumulation of Cd. Reduction in Zn accumulation associated with phosphate application may also contribute to the increase in Cd concentration in durum grain, possibly through enhancement of Cd translocation to the grain. While reduction in Cd concentration in phosphate fertilisers will reduce long‐term Cd accumulation in soils, use of low‐Cd fertiliser at commercially practical levels of fertilisation is unlikely to reduce Cd concentration in durum wheat in the year of application. © 2002 Society of Chemical Industry  相似文献   
59.
富含Zn、Cd和Cl的锡冶炼烟尘,直接返回熔炼对粗锡直收率与质量会有十分不利的影响,所以在返回熔炼前需要进行预先除杂。试验通过两段浸出的方式分别脱出烟尘中的Zn、Cd和Cl三种杂质。结果表明,在优化试验条件下,一段水溶段有90.82%的Cd、95.78%的Cl和39.68%的Zn被浸出;再经二段硫酸浸出,Zn综合浸出率达79.83%,Cd综合浸出率达99.31%,Cl综合浸出率达96.02%。  相似文献   
60.
《分离科学与技术》2012,47(9):1349-1355
A new silica gel material covalently bonded with 1-(pyridin-2-yl) imine (SiNPn) was synthesized and well characterized by elemental analysis, FT–IR, 13C NMR of the solid state, nitrogen adsorption-desorption isotherm, BET surface area, B.J.H. Pore sizes, thermogravimetry curves (TGA), and scanning electron microscope (SEM). The new chelating surface exhibits good chemical and thermal stability. The adsorption capabilities of this new system towards toxic metal ions (Hg2+, Cd2+, Pb2+, and Zn2+) were investigated using the batch method. The percentage limits of extraction were determined by atomic absorption measurements.  相似文献   
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