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21.
A simple, less time consuming, cost ineffective sol–gel method was used to synthesis TiO2 nanoparticles (TiO2) and TiO2–SiO2 nanocomposites (TiO2–SiO2) using titanium tetra isopropoxide as TiO2 and silicic acid as SiO2 precursors respectively. The synthesized nanocomposites were characterized by XRD, SEM, TEM, UV–visible, FTIR and BET analysis. The quantum confinement effect of TiO2 and TiO2–SiO2 was confirmed by a blueshift observed in UV–visible spectra. The band observed at 950 cm−1 in FTIR analysis confirmed the presence of Ti–O–Si bonds, the TEM analysis shows both the TiO2 and TiO2–SiO2 were in nanometer size. The BET (Brunauer– Emmett–Teller) specific surface areas of the samples were 65 and 75 m2/g for TiO2 and TiO2–SiO2 respectively. The power conversion efficiency (PCE) of the nanocomposites were studied by using Keithely electrometer and multimeter and it was found to be 2% and 2.5% for eosin-Y sensitized TiO2 and TiO2–SiO2 nanocomposites respectively. 相似文献
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Murial L. Ross Jeffrey Kunkel Steven Long Prashanth Asuri 《International journal of molecular sciences》2020,21(22)
Confinement and crowding have been shown to affect protein fates, including folding, functional stability, and their interactions with self and other proteins. Using both theoretical and experimental studies, researchers have established the independent effects of confinement or crowding, but only a few studies have explored their effects in combination; therefore, their combined impact on protein fates is still relatively unknown. Here, we investigated the combined effects of confinement and crowding on protein stability using the pores of agarose hydrogels as a confining agent and the biopolymer, dextran, as a crowding agent. The addition of dextran further stabilized the enzymes encapsulated in agarose; moreover, the observed increases in enhancements (due to the addition of dextran) exceeded the sum of the individual enhancements due to confinement and crowding. These results suggest that even though confinement and crowding may behave differently in how they influence protein fates, these conditions may be combined to provide synergistic benefits for protein stabilization. In summary, our study demonstrated the successful use of polymer-based platforms to advance our understanding of how in vivo like environments impact protein function and structure. 相似文献
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《Thin》2014
Concrete-filled double-skin tubular (CFDST) column is one of the most efficient forms of column construction in which the steel tubes provides both axial strength and confining pressure to enhance the strength and ductility of the in-filled concrete. Compared with confined reinforced concrete columns, CFDST columns had stronger and more uniform confining pressure provided to the in-filled concrete by the steel tubes, which reduces the steel congestion problem for better concrete placing quality. However, a major shortcoming of the CFDST columns is the imperfect interface bonding that occurred at the elastic stage that reduces the elastic strength and stiffness of columns. To improve the situation, it is proposed in this study to use external steel rings to restrict the dilation of outer steel tube of CFDST columns. For verification, a series of uni-axial compression test was performed on some CFDST columns with external steel rings. From the results, it was found that the elastic strength, elastic stiffness and ductility were enhanced by installing the steel rings as external confinement. Lastly, a theoretical model for predicting the axial strength of confined CFDST columns has been developed. 相似文献
24.
K. Erik J. Olofsson Anton Soppelsa Tommaso Bolzonella Giuseppe Marchiori 《Control Engineering Practice》2013,21(7):917-929
Input–output datasets from two magnetic confinement fusion (MCF) experiments of the reversed-field pinch (RFP) type are examined. The RFP datasets, which are samples of the distributed magnetic field dynamics, are naturally divided into many smaller batches due to the pulsed-plasma operation of the experiments. The two RFP experiments considered are (i) EXTRAP T2R (T2R) with 64 inputs and 64 outputs and (ii) RFX-mod (RFX) with 192 inputs and 192 outputs. Both T2R and RFX are magnetohydrodynamically unstable and operates under magnetic feedback with optional dither injection. Using subspace system identification techniques and randomised cross-validation (CV) methods to minimise the generalisation error, state-space orders of the empirical systems are suggested. These system orders are compared to “stabilisation diagrams” commonly used in experimental modal analysis practice. The relation of the CV system order to the decay of the singular values from the subspace method is observed. Both (i) stable vacuum diffusion and (ii) unstable plasma response datasets are analysed. Apparent simulation and prediction errors are quantified for both cases using a deviation-accounted-for index. These results are purely data-driven. A simple approach towards exploitation of the subspace techniques for finite-element model refinement and data confrontation is presented. 相似文献
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FRP约束钢管混凝土长柱承载力研究 总被引:1,自引:0,他引:1
已有研究表明,钢管混凝土柱和FRP约束混凝土柱承载力的计算方法不适用于FRP约束钢管混凝土柱承载力的计算。为研究FRP约束钢管混凝土长柱的承载力,本文以钢管约束效应系数ξs和FRP约束效应系数ξf为主要参数,考虑混凝土强度等级对FRP约束钢管混凝土柱承载力提高效果的调整系数,建立了FRP约束钢管混凝土短柱承载力的计算模型。在此基础上,分别引入钢管混凝土稳定系数φs和FRP约束混凝土柱稳定系数φf,建立FRP约束钢管混凝土长柱的承载力计算模型。并将模型的计算结果与试验数据进行比较。 相似文献
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Andreas K. Michler 《International journal for numerical methods in engineering》2011,88(10):986-1007
In this paper, mesh deformation based on radial basis function (RBF) interpolation is applied to the deflection of aircraft control surfaces. A confinement technique is presented, which locally restricts mesh deformation to the vicinity of the moving component and leaves the surfaces of other components unaffected. This technique is shown to have the potential to significantly reduce the CPU time necessary for evaluating the RBF interpolants. Motivated by the directionality of control surface deflection, the idea of treating each direction of the displacements separately is introduced. It is employed for the adaptive selection of centers, and the approach termed sequential uni‐variate center adaptation. It is shown to be more efficient for both solution and evaluation processes than the standard approach, in which the same set of centers is used for every direction. Furthermore, different data sites may be imposed for different directions. It is demonstrated that this enables sliding motion of the elements on the face of a mesh block. Thereby, large control surface deflections are possible, despite the presence of a small spanwise gap between control surface and parent component. These techniques are successfully applied to the deflection of aileron and horizontal tail of a generic fighter aircraft configuration. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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