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21.
The law of mixtures applied to the plastic deformation of two- phase alloys of coarse microstructures 总被引:3,自引:0,他引:3
The theory of the mechanical law of mixtures is reviewed and applied to the partition of stress and of strain in two-phase
alloys. It is shown that the modified law of mixtures, based on averagein situ stress and strain, is valid for small deformations and is compatible with strengthening theories based on continuum and dislocation
mechanics. The plastic deformation behavior of two representative two-phase alloys,i.e., a spheroidized high carbon steel and a duplex stainless steel, was studied by taking into account the mutual interactions
between phases. The law of mixtures and dispersion strengthening theory were used to evaluate the strength contribution of
each phase. 相似文献
22.
23.
Sludge disintegration treatment by using simultaneously ultrasonic irradiation and electrolysis was investigated experimentally. A lab-scale diaphragm cell irradiated with ultrasound at a constant oscillating frequency of 20 kHz was used as a reactor. The batch experiments were carried out under different conditions of electric outputs of the ultrasonic generator, electric current for the electrolysis and different initial SS concentrations. A simultaneous treatment in the cathodic compartment without any chemical doses considerably facilitated the sludge solubilization, compared to the sonication alone. An increase in the electric current up to 400 mA under a constant ultrasonic density decreased the specific energy by 55% within the experimental range. The specific energy consumption was also reduced when the initial SS concentration increased. In addition, before carrying out the simultaneous treatment, a brief electrolysis was effective for further reduction of the specific energy and the acceleration of soluble COD generation. 相似文献
24.
This study described a development and an experimental evaluation of an efficient aerodynamic lens inlet of the single particle mass spectrometry. Several key designing parameters and systematic factors were investigated for the whole lens system through a full numerical simulation. From many tests for various designs of the system, we showed that Mach number was not an independent parameter but interrelated well with flow Reynolds numbers and pressures upstream of the orifices. By manipulating the parameters, we showed for the first time a possibility that there exist a universal correlation between optimal Stokes number and a new factor incorporating the other dimensionless variables and a design parameter. The universality was confirmed by the full simulation results. We demonstrated that the new design of the system was capable of focusing ultrafine aerosols in the size range of 30–700 nm. At two different operating conditions, the formations of sub-millimeter beams of 30–300 nm NaCl aerosols are verified by light scattering imaging as well as microprobe observation of deposited aerosol beams. Finally, the measured sizes of aerosol beams agree reasonably well with those from the simulations as a function of particle size. 相似文献
25.
Y Tamura S Takashima JM Cho W Qi K Kamiguchi T Torigoe S Takahashi I Hirai N Sato K Kikuchi 《Canadian Metallurgical Quarterly》1996,87(6):623-630
Certain MHC class I molecules on target cells are known to inhibit the cytotoxic action of NK cells. By using monoclonal antibody (mAb) Cho-1, we have found inhibitory non-MHC class I cell surface molecules that are noncovalently-associated with 200 kDa and 40 kDa antigens. Poly I-C-induced rat NK cells were not cytotoxic to rat fetus-derived fibroblast WFB cell line. In contrast, NK cells were cytotoxic to H-ras oncogene-induced transformants of WFB, W14 and W31. FACS analysis indicated that mAb Cho-1 reacts with WFB, but not with W14 and W31 cells. Thus, this antigen may disappear concomitantly with cell growth and transformation. Cho-1 antigens were also expressed on other NK-resistant lines, such as mouse BALB3T3 fibroblast, EL-4 lymphoma and human fibroblast HEPM. However, they were not expressed on NK-sensitive mouse YAC-1 and H-ras transformant (Brash) of BALB3T3 cells. Furthermore, treatment of target cells with IFN-gamma clearly induced the cell surface expression of Cho-1 antigens, and conferred a resistance to NK cytolysis on target cells. These data strongly suggest that Cho-1 antigen expression may correlate with target cell susceptibility to NK cells. Indeed, treatment of NK-resistant WFB as well as HEPM cells with F(ab')2 fragments of mAb Cho-1 resulted in the acquisition of susceptibility to NK cytolysis. Cho-1 antigens may be novel molecules that regulate the NK resistance of cells. 相似文献
26.
In arc welding processes, because of the complexity and nonlinearity of heat transfer phenomena, it is often difficult to design an effective control system based upon an exact mathematical model. In this paper, a self-organizing fuzzy control method is proposed to obtain a uniform weld quality by regulation of the surface temperature at a desired level. The proposed control system is designed to comprise a combined structure of the fuzzy SOC with conventional PD control for improving the system's stability. The control experiments show that the proposed controller guarantees a uniform weld quality for various welding conditions. 相似文献
27.
28.
In this work, we designed, fabricated and tested a disposable, flow-through amperometric sensor for free chlorine determination in water. The sensor is based on the principle of an electrochemical cell. The substrate, as well as the top microfluidic layer, is made up of a polymer material. The advantages include; (a) disposability from low cost; (b) stable operation range from three-electrode design; (c) fluidic interconnections that provide on line testing capabilities; and (d) transparent substrate which provides for future integration of on-chip optics. The sensor showed a good response and linearity in the chlorine concentration ranging from 0.3 to 1.6 ppm, which applies to common chlorination process for drinking water purification. 相似文献
29.
Jung‐Hyun Cho Michael Bass Hans P. Jenssen 《Journal of the Society for Information Display》2007,15(12):1029-1036
Abstract— Several rare‐earth‐doped fluoride crystals that are excited to emit visible light by sequential two‐photon absorption have been investigated as display‐medium candidates for static volumetric three‐dimensional displays. Dispersion of powders of these materials in a refractive‐index‐matched polymer is reported because such a medium may result in a scalable display. The scattering problem in such a medium is greatly reduced by index‐matching the polymer to the crystalline particles. An index‐matching condition that optimizes the performance is identified. 相似文献
30.
N Cho Y Nara M Harada T Sugo Y Masuda A Abe K Kusumoto Y Itoh T Ohtaki T Watanabe S Furuya 《Canadian Metallurgical Quarterly》1998,46(11):1724-1737
On the basis of structural information for the cyclic hexapeptide endothelin (ET) receptor antagonist, TAK-044, a series of thieno[2,3-d]pyrimidine-2,4-dione derivatives bearing a carboxyl group and aromatic rings that were important for receptor binding were designed, synthesized, and evaluated for ET receptor binding affinities and inhibitory activities against ET-induced vasoconstriction. Optimization of each substituent in the thieno[2,3-d]pyrimidine ring led to the discovery of a novel and potent nonpeptide ET receptor antagonist, 6-(4-methoxymethoxyphenyl)-5-methylsulfonylaminomethyl-1-(2- methylthiobenzyl)-2,4-dioxo-1,2,3,4-tetrahydrothieno[2,3-d]p yrimidine-3- acetic acid (32 g), which binded to human ETA and ETB receptor subtypes with affinities (IC50) of 7.6 and 100 nM, respectively. Compound 32 g effectively antagonized ET-induced vasoconstriction and the inhibitory effect mediated by the ETB receptor was more potent than that of bosentan, while the inhibitory effect mediated by the ETA receptor was slightly less potent than that of bosentan. 相似文献