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51.
For the first time a novel, simple and facile approach is described to construct highly stable glucose oxidase (GOx) multilayer onto glassy carbon (GC) electrode using thiourea (TU) as a covalent attachment cross-linker. The layer by layer (LBL) attachment process was confirmed by cyclic voltammetry, electrochemical impedance spectroscopy and Fourier transform infrared reflection spectroscopy (FT-IR-RS) techniques. Immobilized GOx shows excellent electrocatalytic activity toward glucose oxidation using ferrocenemethanol as artificial electron transfer mediator and biosensor response was directly correlated to the number of bilayers. The surface coverage of active GOx per bilayer, heterogeneous electron transfer rate constant (ks) and Michaelis–Menten constant (KM), of immobilized GOx were 1.50 × 10−12 mol cm−2, 9.2 ± 0.5 s−1 and 3.42(±0.2) mM, respectively. The biosensor constructed with four-bilayers of TU/GOx showed good stability, high reproducibility, long life-time, fast amperometric response (5 s) with the high sensitivity of 5.73 μA mM−1 cm−2 and low detection limit of 6 μM at concentration range up to 5.5 mM. 相似文献
52.
为科学决策和评价驾驶人情绪感知装置的最优化多模态组合方案, 本文基于可拓设计多功能产品创造法, 利用基元理论中的发散分析法分析了情绪感知装置的检测功能, 建立了类物元,并生成具体产品物元模型。分析了单一检测装置包含的3种安装位置间的重组关系, 拓展出一系列重组方案, 再利用优度评价法对其进行筛选。 最终确定了一种有效的多模态驾驶人情绪感知装置的组合方案。 相似文献
53.
郑曦阳 《南京建筑工程学院学报》1997,(3):78-82
概述了室内装饰品的分类,特性和地位。论述了装饰品在室内空间的空间感调节,空间划分,实用功能以及情感语言等效应,强调了装饰品在室内空间的重要性和必要性,提出:恰当地选择,放置和使用装饰品是室内设计成败的重要环节。 相似文献
54.
55.
Horseshoe vortex topological structure has been studied extensively in the past, traditional “saddle of separation” and new “attachment saddle point” topologies found in literature both have theoretical basis and experimental and computational evidences for support. The laminar incompressible juncture flows at low Reynolds numbers especially are observed to have new topology. Studies concerning the existence of the new topology though found in literature, the topological evolution and its dependency on various critical flow parameters require further investigation. A Particle Image Velocimetry based analysis is carried out to observe the effect of aspect ratio, δ*/D and shape of the obstacle on laminar horseshoe vortex topology for small obstacles. Rise in aspect ratio evolves the topology from the traditional to new for all the cases observed. The circular cross section obstacles are found more apt to having the new topology compared to square cross sections. It is noted that the sweeping effect of the fluid above the vortex system in which horseshoe vortex is immersed plays a critical role in this evolution. Topological evolution is observed not only in the most upstream singular point region of horseshoe vortex system but also in the corner region. The corner vortex topology evolves from the traditional type to new one before the topological evolution of the most upstream singular point, resulting in a new topological pattern of the laminar juncture flows “separation-attachment combination”. The study may help extend the understanding of the three-dimensional boundary layer separation phenomenon. 相似文献
56.
Mengxing Dong Zhuofu Wu Ming Lu Zhi Wang Zhengqiang Li 《International journal of molecular sciences》2012,13(9):11443-11454
Aminopropyl-functionalized SBA-15 mesoporous silica was used as a support to adsorb myoglobin. Then, in order to avoid the leakage of adsorbed myoglobin, lysozyme was covalently tethered to the internal and external surface of the mesoporous silica with glutaraldehyde as the coupling agent. The property of amino-functionalized mesoporous silica was characterized by N2 adsorption-desorption and thermogravimetric (TG) analysis. The feature of the silica-based matrix before and after myoglobin adsorption was identified by fourier transform infrared (FTIR) and UV/VIS measurement. With o-dianisidine and H2O2 as the substrate, the peroxidase activity of adsorbed myoglobin was determined. With Micrococus lysodeilicus as the substrate, the antibacterial activity of covalently tethered lysozyme was measured. Results demonstrated that the final product not only presented peroxidase activity of the myoglobin but yielded antibacterial activity of the lysozyme. 相似文献
57.
Li‐Chen Ou 《Color research and application》2012,37(3):205-205
The Technical Committee 1‐86 of the International Commission on Illumination on “Models of colour emotion and harmony” is requesting the submission of datasets for use in developing new models of colour emotion and colour harmony. The data should be submitted to the TC Chair, Dr. Li‐Chen Ou at the National Taiwan University of Science and Technology. © 2012 Wiley Periodicals, Inc. Col Res Appl, 2012 相似文献
58.
Li‐Chen Ou M. Ronnier Luo Pei‐Li Sun Neng‐Chung Hu Hung‐Shing Chen Shing‐Sheng Guan Andrée Woodcock José Luis Caivano Rafael Huertas Alain Treméau Monica Billger Hossein Izadan Klaus Richter 《Color research and application》2012,37(1):23-43
Psychophysical experiments were conducted in the UK, Taiwan, France, Germany, Spain, Sweden, Argentina, and Iran to assess colour emotion for two‐colour combinations using semantic scales warm/cool, heavy/light, active/passive, and like/dislike. A total of 223 observers participated, each presented with 190 colour pairs as the stimuli, shown individually on a cathode ray tube display. The results show consistent responses across cultures only for warm/cool, heavy/light, and active/passive. The like/dislike scale, however, showed some differences between the observer groups, in particular between the Argentinian responses and those obtained from the other observers. Factor analysis reveals that the Argentinian observers preferred passive colour pairs to active ones more than the other observers. In addition to the cultural difference in like/dislike, the experimental results show some effects of gender, professional background (design vs. nondesign), and age. Female observers were found to prefer colour pairs with high‐lightness or low‐chroma values more than their male counterparts. Observers with a design background liked low‐chroma colour pairs or those containing colours of similar hue more than nondesign observers. Older observers liked colour pairs with high‐lightness or high‐chroma values more than young observers did. Based on the findings, a two‐level theory of colour emotion is proposed, in which warm/cool, heavy/light, and active/passive are identified as the reactive‐level responses and like/dislike the reflective‐level response. © 2010 Wiley Periodicals, Inc. Col Res Appl, 2012 相似文献
59.
《分离科学与技术》2012,47(15):2243-2251
This study conducted a series of tests and simulations to estimate collision-attachment efficiency using a trajectory analysis method, to evaluate model sensitivity due to major impact factors in designing and operating dissolved air flotation (DAF) for the various types of wastewaters, and to find the possibility of model application in determining the flotation efficiency of DAF. Collision-attachment efficiency between a bubble and a particle in the model is described by hydrodynamics related to stream function in Stokes’ flow and surface forces based on a classic DLVO theory, encoded using Matlab language software, and performed numerical analysis using the 5th Runge-Kutta method. Model simulation examined the effects of two major factors, size and zeta potential, on collision-attachment efficiency during flotation and field experiment evaluated to model results. Both results from the simulation and field experiment indicated that the larger particles presented the better collision and removal efficiency and the effect of particle zeta potential on collision-attachment efficiencies was increased as the particle zeta potential increased from the negative domain to the positive domain. Therefore, the collision-attachment efficiency model using the trajectory analysis method may be used in estimating the flotation efficiency and in explaining its characteristics. 相似文献
60.
Aminoalkanethiol surface modifiers were investigated on gold electrodes. It was established, that quinone molecules could be attached to these surface layers in three different forms with well-distinguished redox potentials. Chemical reaction with the amino groups of the modifiers could produce monosubstituted and disubstituted quinones attached covalently to the layers. However, a third form could be detected, as well that seems to be quinone attached non-covalently to the monosubstituted quinone molecules. 相似文献