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71.
For the development of all-solid-state lithium metal batteries (LMBs), a high-porous silica aerogel (SA)-reinforced single-Li+ conducting nanocomposite polymer electrolyte (NPE) is prepared via two-step selective functionalization. The mesoporous SA is introduced as a mechanical framework for NPE as well as a channel for fast lithium cation migration. Two types of monomers containing weak-binding imide anions and Li+ cations are synthesized and used to prepare NPEs, where these monomers are grafted in SA to produce SA-based NPEs (SANPEs) as ionomer-in-framework. This hybrid SANPE exhibits high ionic conductivities (≈10−3 S cm−1), high modulus (≈105 Pa), high lithium transference number (0.84), and wide electrochemical window (>4.8 V). The resultant SANPE in the lithium symmetric cell possesses long-term cyclic stability without short-circuiting over 800 h under 0.2 mA cm−2. Furthermore, the LiFePO4|SANPE|Li solid-state batteries present a high discharge capacity of 167 mAh g−1 at 0.1 C, good rate capability up to 1 C, wide operating temperatures (from −10 to 40 °C), and a stable cycling performance with 97% capacity retention and 100% coulombic efficiency after 75 cycles at 1 C and 25 °C. The SANPE demonstrates a new design principle for solid-state electrolytes, allowing for a perfect complex between inorganic silica and organic polymer, for high-energy-density LMBs.  相似文献   
72.
We previously reported on an extremely small temperature coefficient of resistivity (TCR) of thin amorphous Ni-Si film resistors fabricated by new flash evaporating method, which have a wide range of resistivity.1 In the present paper, we describe the structural and chemical properties of these films for the purpose of clarifying the cause of resistive change of films resulting from heat treatment. X-ray diffraction patterns show that Ni-Si films with greater than 20 wt.% Si remains predominantly amorphous after heat treatment. Changes in composition and binding energy of the films resulting from heat treatment are measured by means of XPS. Electrical characteristics are also investigated as a function of Si concentration and temperature. The resistance variations resulting from heat treatment are found to originate from a structural change. The activation energy needed for this change is obtained by analyzing the extent of change during isothermal heating and found to vary from 1 eV to 2.5 eV with increasing Si content from 20 wt.% to 80 wt.%.  相似文献   
73.
ZL111铝合金表面Ni-Cr-Al激光熔覆层中的非晶组织   总被引:2,自引:0,他引:2  
利用5kWCO2激光器激光熔覆铝合金表面的Ni-Cr-Al涂层,SEM与TEM分析结果表明,在激光熔覆层中存在有非晶组织,非晶组织呈空间扭曲薄片或杉叶状,它们分别存在于熔覆层颗粒间白色网状组织与颗粒中  相似文献   
74.
By adding a gold core to silica nanoparticles (BrightSilica), silica‐like nanoparticles are generated that, unlike unmodified silica nanoparticles, provide three types of complementary information to investigate the silica nano‐biointeraction inside eukaryotic cells in situ. Firstly, organic molecules in proximity of and penetrating into the silica shell in live cells are monitored by surface‐enhanced Raman scattering (SERS). The SERS data show interaction of the hybrid silica particles with tyrosine, cysteine and phenylalanine side chains of adsorbed proteins. Composition of the biomolecular corona of BrightSilica nanoparticles differs in fibroblast and macrophage cells. Secondly, quantification of the BrightSilica nanoparticles using laser ablation inductively coupled plasma mass spectrometry (LA‐ICP‐MS) micromapping indicates a different interaction of silica nanoparticles compared to gold nanoparticles under the same experimental conditions. Thirdly, the metal cores allow the investigation of particle distribution and interaction in the cellular ultrastructure by cryo nanoscale X‐ray tomography (cryo‐XT). In 3D reconstructions the assumption is confirmed that BrightSilica nanoparticles enter cells by an endocytotic mechanism. The high SERS intensities are explained by the beneficial plasmonic properties due to agglomeration of BrightSilica. The results have implications for the development of multi‐modal qualitative and quantitative characterization in comparative nanotoxicology and bionanotechnology.  相似文献   
75.
76.
Noble metal nanostructures are grown inside hollow mesoporous silica microspheres using “ship‐in‐a‐bottle” growth. Small Au seeds are first introduced into the interior of the hollow microspheres. Au nanorods with synthetically tunable longitudinal plasmon wavelengths and Au nanospheres are obtained through seed‐mediated growth within the microspheres. The encapsulated Au nanocrystals are further coated with Pd or Pt shells. The microsphere‐encapsulated bimetallic core/shell nanostructures can function as catalysts. They exhibit high catalytic performance and their stability is superior to that of the corresponding unencapsulated core/shell nanostructures in the catalytic oxidation of o‐phenylenediamine with hydrogen peroxide. Therefore, these hollow microsphere‐encapsulated metal nanostructures are promising as recoverable and efficient catalysts for various liquid‐phase catalytic reactions.  相似文献   
77.
采用热丝化学汽相淀积 (CVD) ,未用别的辅助措施 ,合成了 (10 0 )晶面的金刚石膜。结合CVD金刚石成核的微观过程 ,探讨了定向金刚石膜的形成机理。发现和研究了表面扩散对CVD金刚石成核的重要影响。  相似文献   
78.
一种能有效抑制背光照影响的非晶硅薄膜晶体管   总被引:1,自引:0,他引:1  
提出了一种能有效抑制背光照影响的非晶硅薄膜晶体管结构。详细地分析了源、漏电极接触区和沟通区内载流子的输运特性。论述了在背光照射下,这种结构的TFT能有铲抑制关态电流上升的机理。研究了有源层a-Si:H膜层厚度对TFT关态电流和开态电流的影响。检测辽种结构TFT在暗态和背照射下的静态特性。  相似文献   
79.
Recent insight into the molecular mechanisms of biological mineral formation (biomineralization) has enabled biomimetic approaches for the synthesis of functional organic‐inorganic hybrid materials under mild reaction conditions. Here we describe a novel method for enzyme immobilization in thin (nanoscale) conformal mineral coatings using biomimetic layer‐by‐layer (LbL) mineralization. The method utilizes a multifunctional molecule comprised of a naturally‐occurring peptide, protamine (PA), covalently bound to the redox enzyme Glucose oxidase (GOx). PA mimics the mineralizing properties of biomolecules involved in silica biomineralization in diatoms, and its covalent attachment to GOx does not interfere with the catalytic activity. Highly efficient and stable incorporation of this modified enzyme (GOx‐PA) into nanoscale layers (~5–7 nm thickness) of Ti‐O and Si‐O is accomplished during protamine‐enabled LbL mineralization on silica spheres. Depending on the layer location of the enzyme and the type of mineral (silica or titania) within which the enzyme is incorporated, the resulting multilayer biocatalytic hybrid materials exhibit between 20–100% of the activity of the free enzyme in solution. Analyses of kinetic properties (Vmax, KM) of the immobilized enzyme, coupled with characterization of physical properties of the mineral‐bearing layers (thickness, porosity, pore size distribution), indicates that the catalytic activities of the synthesized hybrid nanoscale coatings are largely determined by substrate diffusion rather than enzyme functionality. The GOx‐PA immobilized in these nanoscale layers is substantially stabilized against heat‐induced denaturation and largely protected from proteolytic attack. The method for enzyme immobilization described here enables, for the first time, the high yield immobilization and stabilization of enzymes within continuous, conformal, and nanoscale coatings through biomimetic LbL mineralization. This approach will likely be applicable to a wide variety of surfaces and functional biomolecules. The ability to synthesize thin (nanoscale) conformal enzyme‐loaded layers is of interest for numerous applications, including enzyme‐based biofuel cells and biosensors.  相似文献   
80.
吴雪  杨富尧  马光  陈新  韩钰  赵蕊 《电测与仪表》2018,55(23):29-33
阐述了软磁材料磁性能测量使用的单片测试方法,包括电流法和H-coil法。采用单片H-coil法对不同工况下非晶合金带材的工频磁性能进行测试,对比正弦工况与谐波工况条件下的磁性能变化差异。  相似文献   
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