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11.
S J Chung S Balaji M Matheswaran T Ramesh I S Moon 《Water science and technology》2007,55(1-2):261-266
This study investigates the hybrid mediated electrochemical oxidation (HMEO) technology, which is a newly developed non thermal electrochemical oxidation process for organic destruction. A combination of ozone and ultrasonication processes to the mediated electrochemical oxidation (MEO) process is termed as hybrid mediated electrochemical oxidation. The electrochemical cell was developed in this laboratory. In the present study, several organic compounds, such as phenol, benzoquinone and ethylenediaminetetraacetic acid (EDTA), were chosen as the model organic pollutants to be destructed by the hybrid process. The organic destruction was monitored based on the CO2 generation and total organic carbon (TOC) reduction. The HMEO process was found to be extremely effective in the destruction of all the target organics chosen in this study. The information obtained from this study will provide an insight in adopting this technique for dealing with more recalcitrant organics (POPs). 相似文献
12.
Public participation is essential in each step of the nuclear-related decision-making process. Recently, the electronic systems using the Internet have become quite popular, and have emerged as a good medium for communicating with the public. In this study, a comprehensive utilization of electronic public participation was used to analyze public opinion on a given nuclear-related decision-making process. The degree of deliberation and meditation of the public participating in an electronic poll survey was evaluated, and the decision-making factors representing the personal characteristics of the poll respondents such as age, income, education, residence, degree of knowledge and concern were carefully incorporated when preparing the poll-survey questionnaire for its evaluation. Fuzzy analysis was used to assess and aggregate the responses to each decision-making factor. As a case study, this procedure was used to analyzing public opinion on the location of a low-level radioactive waste disposal facility on the campus of Seoul National University. The results show that there is a tendency of respondents who are on the negative side of the argument to be more deliberate and meditative in their decision-making process than those on the positive side. Knowledge and residence were found to be important decision-making factors. 相似文献
13.
Zhihui Zhang Bing Q. Han Kyung H. Chung Enrique J. Lavernia 《Metallurgical and Materials Transactions A》2006,37(7):2265-2273
The current study aims to provide fundamental insight into the behavior of microstructures containing grain sizes that span
multiple length scales. A commercial 5083 Al alloy was selected as the material of interest to facilitate comparison with
recently published data. The materials studied here were prepared via the thermal consolidation of powders that were cryomilled
for different times (i.e., 0, 2, 4, and 8 hours). Following consolidation, the resultant microstructure was characterized by an equiaxed grain morphology
with a size distribution centered around 200∼300 nm. Dispersed among the 200- to 300-nm grains were coarse-grained regions
or ligaments with a grain size ranging from 600 nm to 2 μm. The occurrence of coarse-grained regions is rationalized on the
basis of recrystallization or subgrain coarsening, whereas the occurrence of equiaxed fine regions is proposed to be a result
of continuous grain growth. Two types of microstructures were selected for study, containing coarse-grained volumes of approximately
28 pct and 43 pct that corresponded to an ultimate tensile strength (UTS) of 566 MPa and 535 MPa, and a fracture strain of
3.2 pct and 3.5 pct, respectively. The observed ductility and the relevant toughening mechanisms were discussed in light of
the presence of multiple length scales. 相似文献
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15.
A two-dimensional finite element model was constructed to analyze the simulated mechanical behavior of a cantilevered fixed partial denture. The variations of the models were made by altering the degree of bone support, the number of splinted abutments, and the length of the pontics. High stress concentrations were observed around the connectors of the fixed prosthesis and the tooth closest to the cantilever. Reduced bone support increased the deflection and stress concentrations. There was reduction in displacement and stress concentration when the teeth were splinted together. To improve the prognosis of the fixed partial denture cantilever, the number of abutments should be increased and the number of pontics decreased. 相似文献
16.
A quartz microbalance technique has been used to study the growth of4He and H2 adsorbed on sodium. In contrast to cesium, adsorption of4He and H2 do occur on a sodium surface. 相似文献
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A systematic study of wall effects on the shear viscosity of short glass fiber-filled polypropylene and polystyrene is presented. The dependence of these effects on capillary radius, shear rate, temperature, and polymer matrix is examined. The “true” viscosity curves of these materials (free from wall effects) can be obtained by an extrapolation procedure. Breakage of glass fibers in the high shear-rate processes of extrusion and injection molding lead to an appreciable reduction of the viscosity of these materials and is probably the more important effect to take into account in these processes. 相似文献
20.
Shye Lin Wu Chung Len Lee Tan Fu Lei Chen C.F. Chen L.J. Ho K.Z. Ling Y.C. 《Electron Device Letters, IEEE》1994,15(4):120-122
In this study, it is demonstrated that the incorporation of fluorine can enhance poly-Si/Si interfacial oxide break-up in the poly-Si emitter contacted p+-n shallow junction formation. The annealing temperature for breaking up the poly-Si/Si interfacial oxide has been found to be as low as 900°C. As a result, the junction depth of the BF2-implanted device is much larger than that of the boron-implanted device 相似文献