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51.
印制电路板生产设备紫外线曝光机的光源系统,其能耗大、使用维护成本高、含汞等缺陷,在倡导节能环保的当今,业界一直致力于改进。UV-LED面光源作为新一代绿色环保紫外线光源,为印制电路板曝光领域带来革命性的变化。文章通过分析传统平行光紫外曝光机光学系统特点,设计了一种平行光紫外线曝光机适用的UV-LED面光源系统,UV-LED灯珠光功率利用率大幅提高,光照均匀性优良,并且不改变曝光机结构的情况下,可直接安装使用。实验表明,采用了复眼式阵列光学透镜结构设计的UV-LED面光源系统,完全可替代传统平行光紫外曝光机光源。 相似文献
52.
We report the structural and optical properties of ZnS thin films fabricated by ion-beam sputtering. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results revealed a polycrystalline ZnS film with zinc blende phase as manifested by diffraction from the (111), (220) and (311) planes. Annealing resulted in the appearance of a metastable wurtzite phase with a concentration up to 26.6%. An energy bandgap, estimated from absorption spectra, was found to vary between 3.32 and 3.40 eV. The lower energy of this bandgap, as compared to bulk ZnS, is associated with the structural point defects along with mixed zinc blende and wurtzite phases of the polycrystalline ZnS films. Ion beam sputtering deposition can be used to tune the optical bandgap for potential applications in optoelectronic materials. 相似文献
53.
We developed a simple and inexpensive synthesis of a large-scale close-packed monolayer of polystyrene sphere arrays, which have a variety of applications. The influence of three step spin speeds, spinning time, solution quantity and relative humidity is studied in order to achieve a large area close-packed monolayer.A relatively high surface coverage and uniform monolayer of PS spheres in the range of 85%–90% are achieved by appropriate control of the preparative parameters. Also the effect of the oxygen plasma etching process on the reduction of PS spheres has been studied. We conclude that it can be useful in industrial applications, because of the fabrication speed, surface coverage, control over PS spheres and cost of the process. 相似文献
54.
55.
Chao Xie Xing‐Tong Lu Xiao‐Wei Tong Zhi‐Xiang Zhang Feng‐Xia Liang Lin Liang Lin‐Bao Luo Yu‐Cheng Wu 《Advanced functional materials》2019,29(9)
Due to its significant applications in many relevant fields, light detection in the solar‐blind deep‐ultraviolet (DUV) wavelength region is a subject of great interest for both scientific and industrial communities. The rapid advances in preparing high‐quality ultrawide‐bandgap (UWBG) semiconductors have enabled the realization of various high‐performance DUV photodetectors (DUVPDs) with different geometries, which provide an avenue for circumventing numerous disadvantages in traditional DUV detectors. This article presents a comprehensive review of the applications of inorganic UWBG semiconductors for solar‐blind DUV light detection in the past several decades. Different kinds of DUVPDs, which are based on varied UWBG semiconductors including Ga2O3, MgxZn1?xO, III‐nitride compounds (AlxGa1?xN/AlN and BN), diamond, etc., and operate on different working principles, are introduced and discussed systematically. Some emerging techniques to optimize device performance are addressed as well. Finally, the existing techniques are summarized and future challenges are proposed in order to shed light on development in this critical research field. 相似文献
56.
介绍了多阳极微道板阵列(MAMA)紫外探测器系统的最新结构与性能,以及高增益MCP工作的基本特性,并给出了对各类高增益MCP测试的结果。 相似文献
57.
深亚微米光学光刻工艺技术 总被引:1,自引:0,他引:1
谢常青 《电子工业专用设备》2000,29(3):8-12
光学光刻的生命力仍然在不断延续 ,即使在 0 13 μm及 0 13 μm以下集成电路制造水平上 ,光学光刻仍然是一个非常重要的候选者。深亚微米光学光刻工艺技术目前面临着越来越严重的挑战。对深亚微米光学光刻中的一些关键工艺技术如移相光刻、光学邻近效应校正、远紫外光刻胶、套刻对准误差等进行了论述。 相似文献
58.
Ultraviolet detectors based on epitaxial ZnO films grown by MOCVD 总被引:30,自引:0,他引:30
Y. Liu C. R. Gorla S. Liang N. Emanetoglu Y. Lu H. Shen M. Wraback 《Journal of Electronic Materials》2000,29(1):69-74
High-quality zinc oxide (ZnO) films were epitaxially grown on R-plane sapphire substrates by metalorganic chemical vapor deposition
at temperatures in the range of 350°C to 600°C. In-situ nitrogen compensation doping was performed using NH3. Microstructural and optical properties of the films, as well as the N-doping effects, were studied. The metal-semiconductor-metal
ultraviolet sensitive photodetectors were fabricated on N-doped epitaxial ZnO films. The detector showed fast photoresponse,
with a rise time of 1 μs and a fall time of 1.5 μs. Low-frequency photoresponsivity, on the order of 400 A/W at 5 V bias,
was obtained. 相似文献
59.
刘雅樑 《光纤与电缆及其应用技术》2014,(2):13-18
随着10GBASE-T用水平对绞铜缆CAT6A(局域网用超六类电缆)标准的出台﹐带来了又一轮网络升级的高潮。深入分析了IEC 61156-5、ANSI/TIA 568C.2和YD/T 926.2—2009三个标准对CAT6A性能的不同要求,并提出对应的控制和解决方案。 相似文献
60.
韦正世 《光纤与电缆及其应用技术》2011,(2):18-21
由于固化前后紫外光(UV)固化涂层材料分子链中>C-C<键上的C-H键面外弯曲振动在810cm-1附近产生的红外特征吸收峰会发生变化,因而采用了傅里叶变换红外光谱法(FTIR)对特种微型光缆外护层固化度进行测定.借此对不同抗氧阻聚、辐照时间等工艺条件下以及长期储存过程中特种微型光缆外护层的固化度进行研究及原因分析,为控... 相似文献