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$ P_{ZZ} = kT\rho \left( {Z_{1} } \right) + \pi kT\rho \left( {Z_{1} } \right)\int\limits_{ - d}^{0} {\rho \left( {Z_{2} } \right)} Z_{2}^{2} g_{Z,H} (d){\text{d}}Z_{2} - \frac{1}{2}\iint {\int\limits_{0}^{2\pi } {\phi^{\prime } \left( {\vec{r}_{2} } \right)\rho \left( {Z_{1} } \right)\rho \left( {Z_{2} } \right)g_{Z,H} (r_{2} )} }{\frac{{Z_{2}^{2} }}{{(R_{2}^{2} + Z_{2}^{2} )^{{\frac{1}{2}}} }}}R_{2} {\text{d}}R_{2} {\text{d}}Z_{2} {\text{d}}\Uptheta ;\quad \left| {\overset{\lower0.5em\hbox{$ P_{ZZ} = kT\rho \left( {Z_{1} } \right) + \pi kT\rho \left( {Z_{1} } \right)\int\limits_{ - d}^{0} {\rho \left( {Z_{2} } \right)} Z_{2}^{2} g_{Z,H} (d){\text{d}}Z_{2} - \frac{1}{2}\iint {\int\limits_{0}^{2\pi } {\phi^{\prime } \left( {\vec{r}_{2} } \right)\rho \left( {Z_{1} } \right)\rho \left( {Z_{2} } \right)g_{Z,H} (r_{2} )} }{\frac{{Z_{2}^{2} }}{{(R_{2}^{2} + Z_{2}^{2} )^{{\frac{1}{2}}} }}}R_{2} {\text{d}}R_{2} {\text{d}}Z_{2} {\text{d}}\Uptheta ;\quad \left| {\overset{\lower0.5em\hbox{ 相似文献
216.
Marzieh Amanabadi Hossein Bahmanyar Zohreh Zarkeshan Mohamad Ali Mousavian 《中国化学工程学报》2009,17(3):366-372
A rotating disc column (RDC) with inner diameter 68 mm and 28 compartments is used in this study. Parameters including Sauter mean diameter, hold-up and mass transfer coefficient are measured experimentally under different operating conditions. The correlations in literature for molecular diffusion and enhancement factor equation including eddy diffusion, circulation and oscillation of drops are evaluated. A new equation for the effective diffusion coefficient as a function of Reynolds number is proposed. The calculated values of mass transfer co-efficient and column height from the previous equations and present equation are compared with the experimental data. The results from the present equation are in very good agreement with the experimental results, which may be used in designing RDC columns. 相似文献
217.
Zohreh Pourhassan N. Haiyang Cui Sakshi Khosa Mehdi D. Davari Karl-Erich Jaeger Sander H. J. Smits Ulrich Schwaneberg Lutz Schmitt 《Chembiochem : a European journal of chemical biology》2022,23(6):e202100702
Type 1 secretion systems (T1SS) have a relatively simple architecture compared to other classes of secretion systems and therefore, are attractive to be optimized by protein engineering. Here, we report a KnowVolution campaign for the hemolysin (Hly) enhancer fragment, an untranslated region upstream of the hlyA gene, of the hemolysin T1SS of Escherichia coli to enhance its secretion efficiency. The best performing variant of the Hly enhancer fragment contained five nucleotide mutations at five positions (A30U, A36U, A54G, A81U, and A116U) resulted in a 2-fold increase in the secretion level of a model lipase fused to the secretion carrier HlyA1. Computational analysis suggested that altered affinity to the generated enhancer fragment towards the S1 ribosomal protein contributes to the enhanced secretion levels. Furthermore, we demonstrate that involving a native terminator region along with the generated Hly enhancer fragment increased the secretion levels of the Hly system up to 5-fold. 相似文献
218.
Rahimi-Ahar Zohreh Khiadani Mehdi Rahimi Ahar Leile Shafieian Abdellah 《Clean Technologies and Environmental Policy》2023,25(7):2157-2184
In this review, flat plate and concentrate-type solar collectors, integrated collector–storage systems, and solar water heaters combined with photovoltaic–thermal modules, solar-assisted heat pump solar water heaters, and solar water heaters using phase change materials are studied based on their thermal performance, cost, energy, and exergy efficiencies. The maximum water temperature and thermal efficiencies are enlisted to evaluate the thermal performance of the different solar water heaters. It is found that the solar water heaters’ performance is considerably improved by boosting water flow rate and tilt angle, modification of the shape and number of collectors, using wavy diffuse and electrodepositioned reflector coating, application of the corrugated absorber surface and coated absorber, use of turbulent enhancers, using thermal conductive working fluid and nanofluid, the inclusion of the water storage tank, and tank insulation. These items increase the heat transfer area and coefficient, thermal conductivity, the Reynolds and Nusselt numbers, heat transfer rate, and energy and exergy efficiencies. The evacuated tube heaters have a higher temperature compared to the collectors with a plane surface. Their thermal performance increases by using all-glass active circulation and heat pipe integration. The concentrative type of solar water heaters is superior to other solar heaters, particularly in achieving higher water temperatures. Their performance improves by using a rotating mirror concentrator. The integration of the system with energy storage components, phase change materials, or a heat pump provides a satisfactory performance over conventional solar water heaters. Graphical abstractModification of solar water heaters 相似文献219.
Two azole-based Schiff bases, namely, 2-(((1H-1,2,4-triazol-3-yl)imino)methyl)-4-bromophenol, TIB , and 4-Bromo-2-((thiazol-2-ylimino)methyl)phenol, BTP , are synthesized and used as corrosion inhibitors for mild steel, MS, in acidic medium. The inhibitive effect of TIB and BTP , in 0.5 m hydrochloric acid, is investigated using weight loss, potentiodynamic polarization, and electrochemical impedance measurements. The optimum concentrations of TIB and BTP for coverage of metal surface are 600 and 400 μM, respectively. An electrochemical impedance study shows that the corrosion of MS is reduced through a charge transfer mechanism. The maximum inhibition efficiencies at optimum concentration of TIB and BTP are ≈83% and ≈81%, respectively. Tafel polarization reveals that the TIB and BTP behave as mixed-type inhibitors, predominantly of cathodic type. The results indicate that the MS surface has been blocked by TIB and BTP molecules following the Langmuir adsorption isotherm. The formed protective layer on MS surface is verified using SEM and EDX techniques. Furthermore, atomic force microscopic study reveals that the current inhibitors increase the surface smoothness of MS by adsorbing on the metallic surface. 相似文献
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