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101.
This paper reports the DC steady-state current-voltage and conductance-voltage characteristics of a Bipolar Field-Effect Transistor(BiFET) under the unipolar(electron) current mode of operation,with bipolar(elec-tron and hole) charge distributions considered.The model BiFET example presented has two MOS-gates on the two surfaces of a thin pure silicon base layer with electron and hole contacts on both edges of the thin base.The hole contacts on both edges of the thin pure base layer are grounded to give zer... 相似文献
102.
This paper reports the physical realization of the Bipolar Field-Effect Transistor (BiFET) and its one-transistor basic building block circuits. Examples are given for the one and two MOS gates on thin and thick, pure and impure base, with electron and hole contacts, and the corresponding theoretical current-voltage characteristics previously computed by us, without generation-recombination-trapping-tunneling of electrons and holes. These ex-amples include the one-MOS-gate on semi-infinite thick impure base transistor (the bulk transistor) and the impure-thin-base Silicon-on-Insulator (SOI) transistor and the two-MOS-gates on thin base transistors (the FinFET and the Thin Film Transistor TFT). Figures are given with the cross-section views containing the electron and hole concen-tration and current density distributions and trajectories and the corresponding DC current-voltage characteristics. 相似文献
103.
对不同状态含氮奥氏体钢板和马氏体钢板进行了抗枪弹与抗杆式模拟弹试验,分析了它们的穿甲机理。含氮奥氏体钢具有优良的抗弹性能,并优于传统马氏体钢的抗弹性能。马氏体钢抗杆式模拟弹防护系数随着强度的提高而提高,呈线性关系,含氮奥氏体钢穿甲防护系数远远高于同一强度级别的马氏体钢。研究表明,含氮奥氏体钢的抗弹性能的提高主要通过冲击硬化,动态强度明显提高,以及通过塑性变形区域增加,使弹丸更多的能量转换成塑性变形能。 相似文献
104.
105.
介绍了石油钻机专用新型CZ28-1250Q/10直流电磁接触器的总体结构和特点,重点研究讨论了新型CZ28-1250Q/10直流电磁接触器电磁系统的设计和关键技术参数的计算. 相似文献
106.
Peter A. Hersh Calvin J. Curtis Maikel F.A.M. van Hest John J. Kreuder Robert Pasquarelli Alex Miedaner David S. Ginley 《Progress in Photovoltaics: Research and Applications》2011,19(8):973-976
This study reports the inkjet printing of Ag front contacts on Aluminum doped Zinc Oxide (AZO)/intrinsic Zinc Oxide (i‐ZnO)/CdS/Cu(In1−xGax)Se2 (CIGS)/Mo thin film photovoltaic cells. The printed Ag contacts are being developed to replace the currently employed evaporated Ni/Al bi‐layer contacts. Inkjet deposition conditions were optimized to reduce line resistivity and reduce contact resistance to the Al:ZnO layer. Ag lines printed at a substrate temperature of 200°C showed a line resistivity of 2.06 µΩ · cm and a contact resistance to Al:ZnO of 8.2 ± 0.2 mΩ · cm2 compared to 6.93 ± 0.3 mΩ · cm2 for thermally evaporated contacts. These deposition conditions were used to deposit front contacts onto high quality CIGS thin film photovoltaic cells. The heating required to print the Ag contacts caused the performance to degrade compared to similar devices with evaporated Ni/Al contacts that were not heated. Devices with inkjet printed contacts showed 11.4% conversion efficiency compared to 14.8% with evaporated contacts. Strategies to minimize heating, which is detrimental for efficiency, during inkjet printing are proposed. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
107.
Thin film transistors (TFT) with an indium based mixed oxide semiconductor are investigated for titanium–gold top-contacts. It is noticed that upon post annealing, in order to remove chemical residuals from top-contact lift-off steps, oxidation of titanium occurs depending on the annealing conditions. Mobility of the TFT is strongly affected by contact oxidation arising from this post lift-off annealing process. Oxidation of the top-contact is facilitated by adsorbed surface oxygen or out-diffusing oxygen from the semiconductor depending on the post lift-off annealing conditions. A passivation layer that binds effectively to surface vacancies and removes adsorbed oxygen species from the semiconductor surface is demonstrated. The combinations of this passivation layer with relatively low temperature and short post lift-off annealing in an oxygen deficient environment result in significantly reduced contact oxidation and subsequently better transistor performance. Contact resistance as low as 90 Ω cm and mobility as high as 5.3 cm2/V s are obtained for solution processed mixed metal oxide semiconductor in top-contact geometry. 相似文献
108.
自然海水中低合金铸铁点蚀的化学-电化学溶解机理 总被引:4,自引:0,他引:4
根据自然海水中低合金铸铁试验结果,在蚀坑内受扩散和迁移控制的质量传输、化学溶解和电化学溶解的基础上,建立自然海水中铸铁点蚀的化学-电化学溶解模型,并推导出蚀坑内电压分布的方程式。此式表明,蚀坑内的电压取决于蚀坑内各类活性腐蚀因子的化学势梯度和相应粒子的电压降。试验结果表明,自然海水中铸铁表面钝化膜的诱发期的局部破坏与海生物的局部附着和生物粘膜下R(R=wCl-wOH-)值密切相关,在其蔓延生长过程中,蚀坑内外的电压降、蚀坑内活性粒子的活度和pH值密切相关。但自然海水中的卤素离子的存在和摩尔分数对铸铁点蚀影响最大。 相似文献
109.
110.
Nan Wei Patrik Laiho Abu Taher Khan Aqeel Hussain Alina Lyuleeva Saeed Ahmed Qiang Zhang Yongping Liao Ying Tian Er‐Xiong Ding Yutaka Ohno Esko I. Kauppinen 《Advanced functional materials》2020,30(5)
In this work, a fast approach for the fabrication of hundreds of ultraclean field‐effect transistors (FETs) is introduced, using single‐walled carbon nanotubes (SWCNTs). The synthesis of the nanomaterial is performed by floating‐catalyst chemical vapor deposition, which is employed to fabricate high‐performance thin‐film transistors. Combined with palladium metal bottom contacts, the transport properties of individual SWCNTs are directly unveiled. The resulting SWCNT‐based FETs exhibit a mean field‐effect mobility, which is 3.3 times higher than that of high‐quality solution‐processed CNTs. This demonstrates that the hereby used SWCNTs are superior to comparable materials in terms of their transport properties. In particular, the on–off current ratios reach over 30 million. Thus, this method enables a fast, detailed, and reliable characterization of intrinsic properties of nanomaterials. The obtained ultraclean SWCNT‐based FETs shed light on further study of contamination‐free SWCNTs on various metal contacts and substrates. 相似文献