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1.
产品名称规格报价…’变硫日期黑钨精矿白钨精矿钨铁仲钨酸按仲钨酸钱(欧)含WO3芬65环(欧)含WO3妻70%(欧)含W>75%(欧)(美)43一53美元/吨度5.40~5.85美元/公斤(钨)64.0~68,0美元/吨度72.0~80.0美元/短吨度奸年l月10日97年1月24日%年6月20日铝精矿三氧化铝铝铁(欧)CIF(美)CIF(欧) 相似文献
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产品名称黑鸽精矿白钨精矿钨铁仲钨酸按仲钨酸按翎精矿锡精矿 规格(欧)含W03》‘5写(欧)含Wq)70%(欧)含W>75%(欧)(美)(欧)CIF(美)CIF(欧)桶装(美)CIF含M。‘5%~70写LME现货LME三个月现货吉隆坡商品交易所纽约现货(欧)现货(欧)三个月期货40%~60%Sn(加工费)‘0%~70%Sn(加工费)70~ 相似文献
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Forrer P Binz HK Stumpp MT Plückthun A 《Chembiochem : a European journal of chemical biology》2004,5(2):183-189
Consensus design is a valuable protein-engineering method that is based on statistical information derived from sequence alignments of homologous proteins. Recently, consensus design was adapted to repeat proteins. We discuss the potential of this novel repeat-based approach for the design of consensus repeat proteins and repeat protein libraries and summarize recent results from such experiments. 相似文献
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A procedure for combining and visualizing complementary structural and functional information from magnetic resonance imaging (MRI) and positron emission tomography (PET) is described. MR and PET images of the human brain were obtained and correlated to form three-dimensional volumes of image data. Volume rendering and solid-texturing concepts were combined to develop a new volume imaging technique for ;volume texture-mapping' brain glucose metabolism (from PET) onto brain anatomy (from MRI). The technique was used to produce sequences of three-dimensional views: these sequences were dynamically displayed in a ;cine-loop' to better visualize the three-dimensional relationship between brain structure and function. The techniques provide a means of presenting vast amounts of multidimensional data in a form that is easily understood, and the resulting images are essential to an understanding of the normal and pathologic states of the human brain. 相似文献
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Wang L Ding Y Patel U Yang W Xiao Z Cai Z Mao WL Mao HK 《The Review of scientific instruments》2011,82(4):043903
In this report, we demonstrate the feasibility of applying a 250-nm focused x-ray beam to study a single crystalline NbSe(3) nanobelt under high-pressure conditions in a diamond anvil cell. With such a small probe, we not only resolved the distribution and morphology of each individual nanobelt in the x-ray fluorescence maps but also obtained the diffraction patterns from individual crystalline nanobelts with thicknesses of less than 50 nm. Single crystalline diffraction measurements on NbSe(3) nanobelts were performed at pressures up to 20 GPa. 相似文献
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This study examined the surface nanostructures of three orbital implants: nonporous poly(methyl methacrylate) (PMMA), porous aluminum oxide and porous polyethylene. The morphological characteristics of the orbital implants surfaces were observed by atomic force microscopy (AFM). The AFM topography, phase shift and deflection images of the intact implant samples were obtained. The surface of the nonporous PMMA implant showed severe scratches and debris. The surface of the aluminum oxide implant showed a porous structure with varying densities and sizes. The PMMA implant showed nodule nanostructures, 215.56 ± 52.34 nm in size, and the aluminum oxide implant showed crystal structures, 730.22 ± 341.02 nm in size. The nonporous PMMA implant showed the lowest roughness compared with other implant biomaterials, followed by the porous aluminum oxide implant. The porous polyethylene implant showed the highest roughness and severe surface irregularities. Overall, the surface roughness of orbital implants might be associated with the rate of complications and cell adhesion. SCANNING 33: 211–221, 2011. © 2011 Wiley Periodicals, Inc. 相似文献
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Inverse sampling suggests one continues to sample subjects until a pre-specified number of rare events of interest is observed. It is generally considered to be more appropriate than the usual binomial sampling when the subjects come sequentially, when the response probability is rare, and when maximum likelihood estimators of some epidemiological measures are undefined under binomial sampling. Reliable but conservative exact conditional procedure for the ratio of the response probabilities of subject without the attribute of interest has been studied. However, such a procedure is inapplicable to the risk ratio (i.e., ratio of the response probabilities of subject with the attribute of interest). In this paper, we investigate various test statistics (namely Wald-type, score and likelihood ratio test statistics) for testing non-unity risk ratio under standard inverse sampling scheme, which suggests one continue to sample until the predetermined number of index subjects with the attributes of interest is observed. Both asymptotic and numerical approximate unconditional methods are considered for P-value calculation. Performance of these test procedures are evaluated under different settings by means of Monte Carlo simulation. In general, the Wald-type test statistic is preferable for its satisfactory and stable performance with approximate unconditional procedures. The methodologies are illustrated with a real example from a heart disease study. 相似文献
10.
To lower the operating temperatures in solid oxide fuel cell (SOFC) operations, anode-supported SOFC single cells with a single dip-coated interlayer were fabricated and the effect of the interlayer on the electrolyte structure and the electrical performance was investigated. For the preparation of SOFC single cells, yttria-stabilized zirconia (YSZ) electrolyte, NiO-YSZ anode, and 50% YSZ-50% strontium-doped lanthanum manganite (LSM) cathode were used. In order to characterize the cells, scanning electron microscopy (SEM) and atomic force microscopy (AFM) were utilized and the gas (air) permeability measurements were conducted for gas tightness estimation. When the interlayer was inserted onto NiO-YSZ anode, the surface roughness of anode was diminished by about 40% and dense crack-free electrolytes were obtained. The electrical performance was enhanced remarkably and the maximum power density was 0.57W/cm(2) at 800 degrees C and 0.44W/cm(2) at 700 degrees C. On the other hand, the effect of interlayer on the gas tightness was negligible. The characterization study revealed that the enhancement in the electrical performance was mainly attributed to the increase of ion transmission area of anode/electrolyte interface and the increase of ionic conductivity of dense crack-free electrolyte layer. 相似文献