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161.
162.
O. Dubreuil M. Cordeau Th. Mourier P. Chausse D. Bellet 《Microelectronic Engineering》2008,85(10):1988-1991
With the downscaling of feature dimensions, copper interconnects exhibit properties differing from bulk or film material. Resistivity increases and limits electrical performances, and reliability of interconnects becomes a more important challenge for each new technological node. In this study, we present an approach of copper grain growth control inside narrow wires by adding a step between the copper electro-chemical deposition (ECD) and the chemical-mechanical polishing (CMP). This step corresponds to a partial CMP step (pre-CMP) and is applied after ECD and before anneal in order to modify the copper overburden thickness. Depending on the targeted thickness, copper grain growth occurs during anneal with different efficiencies. Crystallization and grain growth behaviour inside wires is investigated with focused ions beam (FIB). We present here our methodology for sample preparation and characterization. Results are focused on electrical variations and on morphological aspects of copper crystallization and grain growth inside lines observed with various overburden thicknesses. 相似文献
163.
Ji Qian Fujie Wang Yu Li Shuo Wang Yuanyuan Zhao Wanlong Li Yi Xing Lei Deng Qiang Sun Li Li Feng Wu Renjie Chen 《Advanced functional materials》2020,30(27)
Lithium–sulfur batteries are promising energy‐storage devices because of their high theoretical energy densities. For practical Li–S batteries, reducing the amount of electrolyte used is essential for achieving the high energy densities. However, reducing the electrolyte amount leads to severe performance degradation, mainly because of sluggish deposition of discharge products (Li2S) and the accompanying passivation issue that arise from the insulating nature of Li2S. In this study, a lightweight, robust interlayer, with a 3D open structure and a low surface area is designed and fabricated. The structure facilitates electrolyte infiltration without trapping too much electrolyte. Moreover, the electrocatalytic Co nanoparticles embedded in the skeleton surface within the interlayer effectively promote Li ion diffusion, polysulfides conversion, and Li2S deposition, and therefore enhance the electrochemical kinetics under lean electrolyte conditions. The mechanisms involved in the interlayer effects are investigated by microstructural characterizations, electrochemical performance tests, density functional theory calculations, and in situ X‐ray diffraction characterization. These results show the feasibility of using an interlayer strategy to improve the electrochemical performances of Li–S batteries under lean electrolyte conditions to potentially increase the practical energy densities of Li–S batteries. 相似文献
164.
165.
Device-quality GaAs thin films have been grown on miscut Ge-on-Si substrates by metal-organic chemical vapor deposition. A method of two-step epitaxy of GaAs is performed to achieve a high-quality top-layer. The initial thin buffer layer at 360 ℃ is critical for the suppression of anti-phase boundaries and threading dislocations. The etch pit density ofGaAs epilayers by KOH etching could reach 2.25 × 10^5 cm^-2 and high-quality GaAs top epilayers are observed by transmission electron microscopy. The band-to-band photoluminescence property of GaAs epilayers on different substrates is also investigated and negative band shifts of several to tens of meVs are found because of tensile strains in the GaAs epilayers. To achieve a smooth surface, a polishing process is performed, followed by a second epitaxy of GaAs. The root-mean-square roughness of the GaAs surface could be less than 1 nm, which is comparable with that of homo-epitaxial GaAs. These low-defect and smooth GaAs epilayers on Si are desirable for GaAs-based devices on silicon substrates. 相似文献
166.
首先运用Stober溶胶凝胶法制备单分散Si02球形颗粒,通过扫描电镜研究各种反应条件如氨水浓度、无水乙醇的量、TEOS的浓度、温度等对二氧化硅的颗粒大小和形貌的影响,并通过SEM对样品的表面形貌进行了表征。通过研究改变垂直沉积法的各种条件对组装成的Si02光子晶体的带隙特性的影响。分析微球粒径、悬浮液中微球的体积分数、基片与液面之间所成的角度对光子晶体带隙性能的影响,并总结了较佳的垂直沉积法条件。 相似文献
167.
提出了一种制备多壁碳纳米管的简单方法。以乙醇为碳源,利用催化化学气相沉积工艺制备了碳纳米管。用较为简单的设备在较低的反应温度下,在基底上生长了取向多壁碳纳米管阵列。利用扫描电子显微镜内部的纳米操纵仪对单根碳纳米管进行操纵,并测试了单根多壁碳纳米管的电学特性。 相似文献
168.
Xianchun Peng Jie Sun Huan Liu Liang Li Qikun Wang Liang Wu Wei Guo Fanping Meng Li Chen Feng Huang Jichun Ye 《半导体学报》2022,43(2):79-85
AIN thin films were deposited on c-,a-and r-plane sapphire substrates by the magnetron sputtering technique.The in-fluence of high-temperature thermal annealing (HTTA) on the structural,optical properties as well as surface stoichiometry were comprehensively investigated.The significant narrowing of the (0002) diffraction peak to as low as 68 arcsec of AIN after HTTA implies a reduction of tilt component inside the AIN thin films,and consequently much-reduced dislocation densities.This is also supported by the appearance of E2(high) Raman peak and better Al-N stoichiometry after HTTA.Furthermore,the in-creased absorption edge after HTTA suggests a reduction of point defects acting as the absorption centers.It is concluded that HTTA is a universal post-treatment technique in improving the crystalline quality of sputtered AIN regardless of sapphire orienta-tion. 相似文献
169.
Jaeheung Ha Subeom Park Donghyun Kim Jaechul Ryu Changhee Lee Byung Hee Hong Yongtaek Hong 《Organic Electronics》2013,14(9):2324-2330
Recently, graphene-based organic light emitting diodes (OLEDs) were successfully demonstrated using graphene as anodes. However, the graphene electrodes have not been utilized for polymer light emitting diodes (PLEDs) yet, although the simpler device structure and the solution-based fabrication process of PLEDs are expected to be more advantageous in terms of time and cost. Here we demonstrate high-performance polymer light emitting diodes (PLEDs) with simple two-layer structures using interface-engineered single-layer graphene films as anodes. The single-layer graphene synthesized by chemical vapor deposition methods was transferred onto a glass substrate utilizing an elastic stamp, and its work function was engineered by varying the duration and the power of ultraviolet ozone (UVO) treatment. Thus, we were able to optimize the contact between silver electrodes and the graphene anodes, leading to the considerable enhancement of light-emitting performance. 相似文献
170.
Helen Hejin Park Rachel Heasley Leizhi Sun Vera Steinmann Rafael Jaramillo Katy Hartman Rupak Chakraborty Prasert Sinsermsuksakul Danny Chua Tonio Buonassisi Roy G. Gordon 《Progress in Photovoltaics: Research and Applications》2015,23(7):901-908
Thin‐film solar cells consisting of earth‐abundant and non‐toxic materials were made from pulsed chemical vapor deposition (pulsed‐CVD) of SnS as the p‐type absorber layer and atomic layer deposition (ALD) of Zn(O,S) as the n‐type buffer layer. The effects of deposition temperature and annealing conditions of the SnS absorber layer were studied for solar cells with a structure of Mo/SnS/Zn(O,S)/ZnO/ITO. Solar cells were further optimized by varying the stoichiometry of Zn(O,S) and the annealing conditions of SnS. Post‐deposition annealing in pure hydrogen sulfide improved crystallinity and increased the carrier mobility by one order of magnitude, and a power conversion efficiency up to 2.9% was achieved. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献