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91.
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93.
Studies on toxicity of multi-walled carbon nanotubes on Arabidopsis T87 suspension cells 总被引:1,自引:0,他引:1
The possible toxicities of agglomerates of multi-walled carbon nanotubes (MWCNTs) toward plant cells were evaluated. Arabidopsis T87 suspension cells were used as the model cells and decreases in values of cell dry weights, cell viabilities, cell chlorophyll contents, and superoxide dismutase (SOD) activities were seen for the cells cultured in media containing the agglomerates of MWCNTs, indicating the agglomerates of MWCNTs are toxic to the Arabidopsis T87 suspension cells. Moreover, the toxicities increased sharply as the diameters of the agglomerates of the MWCNTs became smaller. A concept based on the hypersensitive response is suggested to explain the possible toxic mechanism induced by the MWCNTs. 相似文献
94.
A non-doped-type structure was proposed for obtaining organic light-emitting devices with high-efficiency and full-spectrum white light emission. The device structure included indium tin oxide glass substrate/450 Å 4,4′,4″-tris{N-(3-methylphenyl)-N-phenylamin}triphenylamine (m-MTDATA) hole injection layer/100 Å N,N′-bis-(1-naphthyl)-N,N′-diphenyl-1,1′-biph-enyl-4,4′-diamine (NPB) hole transport layer/150 Å 4,4′-bis(2,2′-diphenylvinyl)-1,1′-biphenyl (DPVBi) blue emitting layer/ultrathin [2-methyl-6-[2-(2,3,6,7-tetrahydro-1H, 5H-benzo[ij] quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene] propane-dinitrile (DCM2) yellow-emitting layer/ 80 Å 4,7-diphenyl-1,10-phenanthroline (BPhen) electron transporting layer and hole blocking layer/600 Å tris (8-hydroxyquinoline) aluminium (Alq3) electron-transporting layer /10 Å lithium fluoride (LiF)/aluminum (Al). A white emission (Commission Internationale de l’Eclairage 1931 chromaticity coordinate) (X = 0.3556, Y = 0.3117) at 5 V and (X = 0.282, Y = 0.2658) at 15 V was obtained. Its luminance was 11,497 cd/m2 at 15 V, and the maximum efficiency was 4.8 lm/W at 5 V. 相似文献
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96.
Extensive growth in functional brain imaging, perfusion-weighted imaging, diffusion-weighted imaging, brain mapping and brain
scanning techniques has led tremendously to the importance of cerebral cortical segmentation both in 2-D and 3-D from volumetric
brain magnetic resonance imaging data sets. Besides that, recent growth in deformable brain segmentation techniques in 2-D
and 3-D has brought the engineering community, such as the areas of computer vision, image processing, pattern recognition
and graphics, closer to the medical community, such as to neuro-surgeons, psychiatrists, oncologists, neuro-radiologists and
internists. In Part I of this research (see Suri et al [1]), an attempt was made to review the state-of-the-art in 2-D and
3-D cerebral cortical segmentation techniques from brain magnetic resonance imaging based on two main classes: region- and
boundary/surface-based. More than 18 different techniques for segmenting the cerebral cortex from brain slices acquired in
orthogonal directions were shown using region-based techniques. We also showed more than ten different techniques to segment
the cerebral cortex from magnetic resonance brain volumes using boundary/surface-based techniques. This paper (Part II) focuses
on presenting state-of-the-art systems based on the fusion of boundary/surface-based with region-based techniques, also called
regional-geometric deformation models, which takes the paradigm of partial differential equations in the level set framework.
We also discuss the pros and cons of these various techniques, besides giving the mathematical foundations for each sub-class
in the cortical taxonomy. Special emphasis is placed on discussing the advantages, validation, challenges and neuro-science/clinical
applications of cortical segmentation.
Received: 25 August 2000, Received in revised form: 28 March 2001, Accepted: 28 March 2001 相似文献
97.
本文通过对酒样中沉淀物的定性分析,确定了该沉淀物为CaSO_4·2H_2O,并定量测定了勾兑用水中Ca~(2 )、SO_4~(2-)及活性碳中的SO_4~(2-)含量,从而为避免沉淀的产生提供了科学依据. 相似文献
98.
Refined white sugar is a very pure food product, even though it contains very small amounts of soluble and insoluble impurities. The content of these impurities has nutritional significance and determines the usefulness of sugar for various industrial applications. The main quality criteria used to indicate the content of these impurities are ash and colour. The aim of this paper was to evaluate the quality according to the EU sugar market regime and the content of iron, copper and zinc in white sugar samples from Serbian sugar beet refineries during the 2003 campaign. A total of 166 samples representative of the production of four Serbian sugar refineries were investigated. After wet digestion the concentrations of iron, copper and zinc were determined by flame atomic absorption spectrometry. The mean content of iron, copper and zinc in sugar samples was 0.37 mg/kg, 0.06 mg/kg and 0.02 mg/kg and was significantly different from the average content 0.28 mg/kg, 0.09 mg/kg and 0.07 mg/kg respectively in the analysed European sugar factories. The data were also compared with literature values for commercial white sugar samples from European sugar beet refineries and European legislation set for copper and zinc. Furthermore, the quality of produced sugar was evaluated according to the standards of the European Union indicating that 76% of all investigated Serbian samples belonged to the second sugar quality category. 相似文献
99.
J. Liu X. Guo L. J. Bu Z. Y. Xie Y. X. Cheng Y. H. Geng L. X. Wang X. B. Jing F. S. Wang 《Advanced functional materials》2007,17(12):1917-1925
Four single polymers with two kinds of attachment of orange chromophore to blue polymer host for white electroluminescence (EL) were designed. The effect of the side‐chain attachment and main‐chain attachment on the EL efficiencies of the resulting polymers was compared. The side‐chain‐type single polymers are found to exhibit more efficient white EL than that of the main‐chain‐type single polymers. Based on the side‐chain‐type white single polymer with 4‐(4‐alkyloxy‐phenyl)‐7‐(4‐diphenylamino‐phenyl)‐2,1,3‐benzothiadiazoles as the orange‐dopant unit and polyfluorene as the blue polymer host, white EL with simultaneous orange (λmax = 545 nm) and blue emission (λmax = 432 nm/460 nm) is realised. A single‐layer device (indium tin oxide/poly(3,4‐ethylenedioxythiophene)/polymer/Ca/Al) made of these polymers emits white light with the Commission Internationale de l'Éclairage coordinates of (0.30,0.40), possesses a turn‐on voltage of 3.5 V, luminous efficiency of 10.66 cd A–1, power efficiency of 6.68 lm W–1, and a maximum brightness of 21 240 cd m–2. 相似文献
100.
C. Langlade A. Roman D. Schlegel E. Gete M. Folea 《Materials and Manufacturing Processes》2016,31(12):1565-1572
Superficial nanostructuration by friction stir processing (FSP) experiments has been carried out on samples of AISI 45 steel. Sixteen tests were carried out, with a traverse speed in the range of 10–70 mm/min and 900–1800 N for the normal force at a constant rotational speed of 2000 rpm, in order to determine the optimal conditions for the process applied to this material and to test its feasibility. The results obtained have shown that FSP in this range of parameters leads to the formation of a stirred layer of small grains (30 times smaller than the initial grains) with high hardness (approximately doubled). When the load is higher than 1500 N and the traverse speed is superior to 50 mm/min, a white layer (WL) with very high hardness can be produced. It has also been determined that the increase of the stirred layers’ thickness is almost linked to the increase of the normal force. 相似文献