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41.
The objectives of this study are the correlation between the oil samples recovered from the Lower Cretaceous reservoirs and Lower and Upper Cretaceous source rocks. The investigated biomarkers of five oils indicated the oils were derived from mixed marine and terrigenous (lacustrine) organic matter and deposited under suboxic to anoxic conditions. These oils were also generated from source rocks of high thermal maturity at the peak oil window. So, based on the molecular indicators of organic source input,depositional environment and maturity parameters of oils and extracts, we can conclude that the oil recovered from Al Baraka oil field were derived from Lower Cretaceous source rocks especially KomOmbo (B) source rocks where it reached the oil window. Furthermore, we can indicate that the other lower Cretaceous formations as Abu Ballas Formation will have the opportunity to generate and expel oil at the deeper part of the basin as shown in the eastern part of the basin.  相似文献   
42.
Dry compacts of pure Fe2O3 and Fe2O3 doped with either (2–6 mass%) MnO2, (2.5–7.5 mass%) SiO2 or with both (2–6% MnO2 + 7.5% SiO2) were indurated at 1373 K for 6 hours and physically and chemically characterized. The fired compacts were isothermally reduced with pure CO gas at 1073–1373 K. The O2‐weight loss was continuously recorded as a function of time using TGA technique. The external volume of pure and doped compacts was measured at different reduction conditions and the volume change was calculated. The structural changes accompanying the reduction process were visually and microscopically examined and the different phases were identified by X‐ray diffraction analysis. After firing, manganese ferrite (MnFe2O4) phase was identified in MnO2‐doped compacts. In pure Fe2O3 compacts, the external volume of compacts was increased with reduction temperature, showing a maximum swelling value at 1198 K. Catastrophic swelling was observed in MnO2‐doped Fe2O3 compacts, the volume change increased with MnO2 content showing catastrophic swelling in compacts containing 6%MnO2 at 1248 K. The catastrophic swelling was attributed to the formation of dense metallic iron whiskers and plates in a highly porous structure. Unlike in MnO2‐doped samples, no considerable volume changes were detected in SiO2‐doped Fe2O3 and (MnO2 + SiO2)‐doped Fe2O3 compacts where the presence of silica greatly hindered the swelling phenomenon at all reduction temperatures.  相似文献   
43.
A fast and simple method for the determination of the efficiency coefficient (η) of bare CR-39 detector is presented and discussed. The efficiency coefficient of bare CR-39 detector is then calculated by different ways and the obtained values are found to be comparable to each other. The average value of η of bare CR-39 is found to be 0.20 ± 0.01 tracks cm−2 day−1 per Bq m−3.  相似文献   
44.
In this study Lattice Boltzmann Method (LBM) as an alternative of conventional computational fluid dynamics method is used to simulate Direct Methanol Fuel Cell (DMFC). A two dimensional lattice Boltzmann model with 9 velocities, D2Q9, is used to solve the problem. The computational domain includes all seven parts of DMFC: anode channel, catalyst and diffusion layers, membrane and cathode channel, catalyst and diffusion layers. The model has been used to predict the flow pattern and concentration fields of different species in both clear and porous channels to investigate cell performance. The results have been compared well with results in literature for flow in porous and clear channels and cell polarization curves of the DMFC at different flow speeds and feed methanol concentrations.  相似文献   
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In this paper, a novel multiobjective genetic algorithm approach for economic emission load dispatch (EELD) optimization problem is presented. The EELD problem is formulated as a non-linear constrained multiobjective optimization problem with both equality and inequality constraints. A new optimization algorithm which is based on concept of co-evolution and repair algorithm for handling non-linear constraints is presented. The algorithm maintains a finite-sized archive of non-dominated solutions which gets iteratively updated in the presence of new solutions based on the concept of -dominance. The use of -dominance also makes the algorithms practical by allowing a decision maker to control the resolution of the Pareto-set approximation by choosing an appropriate value.The proposed approach is carried out on the standard IEEE 30-bus 6-genrator test system. The results demonstrate the capabilities of the proposed approach to generate true and well-distributed Pareto-optimal non-dominated solutions of the multiobjective EELD problem in one single run. Simulation results with the proposed approach have been compared to those reported in the literature. The comparison demonstrates the superiority of the proposed approach and confirms its potential to solve the multiobjective EELD problem.  相似文献   
49.
This work studies the tensile strength, coherence, elastic, and plastic energy of single and bi-component compacted tablets consisting of (i) microcrystalline cellulose (MCC) PH 102 as a plastic material, (ii) (SSG) as an elastic material, and (iii) alpha lactose monohydrate as a brittle material by direct compression. Compacted tablets were studied with various mass ratios formed at an ultimate compaction stress of 150 MPa. The loading and unloading stages of the compaction process for the single and binary tablets were evaluated based on the energies derived from the force-displacement data obtained. The resulting tablet quality was measured in terms of the tensile strength. Material that exhibit predominantly plastic deformation (MCC) shows a dominant property over elastically deforming sodium starch glycolate (SSG) and brittle (lactose) materials during the loading and unloading stages of the compaction process. In conclusion, the tensile strength of the formed tablets depends directly on the plastic energy and indirectly on the elastic energy and is negatively affected by the presence of a brittle material.  相似文献   
50.
A new copper‐containing Schiff‐base diamine, benzil bis(thiosemicarbazonato)copper(II) (CuLH4), was synthesized in two steps from benzil bisthiosemicarbazone (LH6). The ligand LH6 and the complex CuLH4 were characterized with Fourier transform infrared spectroscopy, 1H‐NMR, and elemental analysis. CuLH4 was used to prepare novel polyamides. The low‐temperature solution polycondensation of the complex CuLH4 with various aromatic and aliphatic diacid chlorides afforded copper‐containing Schiff‐base polyamides with inherent viscosities of 0.25–0.36 dL/g in N,N‐dimethylformamide (DMF) and 0.75 dL/g in H2SO4 at 25°C. The polyamides were generally soluble in a wide range of solvents, such as DMF, N,N‐dimethylacetamide, tetrahydrofuran, dimethyl sulfoxide, ethyl acetate, tetrachloroethane, hexamethylene phosphoramide, N‐methylpyrrolidone, and pyridine. Thermal analysis showed that these polyamides were practically amorphous, decomposed above 270°C, and exhibited 50% weight loss at and above 400°C. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008  相似文献   
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