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101.
阐述了IPv6下网络协议欺骗的一般原理,详细分析了ICMPv6协议及其存在的漏洞.对于ICMPv6重定向及NS/NA欺骗的原理进行了深入的讨论,并提出了ICMPv6重定向欺骗和NS/NA欺骗的具体实现方法. 相似文献
102.
利用C++Builder与Matlab实现实时数据的获取与处理 总被引:2,自引:1,他引:1
针对航空电气系统实时数据采集环境的复杂性,介绍了采用PC机模拟航空电子公管系统,利用C++Builder完成人机交互界面的设计以及数据的获取与处理;在Borland C++Builder 6环境下,利用其功能强大的图形化控制界面,及MSComm控件在串行口下编程,实现上位机与DSP的SCI通讯模块的通讯;结合Matlab实现供电系统设备状态数据的处理,并通过建立Access数据库,在BCB6中实时存储处理供电系统的各部分状态信息。 相似文献
103.
A cable-driven parallel manipulator is a manipulator whose end-effector is driven by a number of parallel cables instead of
rigid links. Since cables always have more flexibility than rigid links, a cable manipulator bears a concern of possible vibration.
Thus, investigation of vibration of cable manipulators caused by cable flexibility is important for applications requiring
high system stiffness or bandwidth. This paper provides a vibration analysis of general 6-DOF cable-driven parallel manipulators.
Based on the analysis of the natural frequencies of the multibody system, the study demonstrates that a cable manipulator
can be designed stiff enough for special applications like the cable-manipulator based hardware-in-the-loop simulation of
contact dynamics. Moreover, under an excitation, a cable may vibrate not only in its axial direction, but also in its transversal
direction. The paper also analyzes the vibration of cable manipulators caused by cable flexibilities in both axial and transversal
directions. It is shown that the vibration of a cable manipulator due to the transversal vibration of cables can be ignored
comparing to that due to the axial flexibility of cables. 相似文献
104.
基于多信息融合技术的智能汽车防盗报警系统研究与设计 总被引:2,自引:0,他引:2
为完善汽车的防盗系统,提出研制的智能汽车防盗报警器是在ARM嵌入式系统的基础上,利用Dempster--Sharer证据理论融合密码识别、加速度传感、GPS全球定位信息,判断车辆的安全状况,再将车况信息通过GPRS无线通信网络发送到车主手机。实验室测试表明,系统实现了监控基本功能并满足实时性,增强了汽车安全性和智能报警性。 相似文献
105.
通过改进GPU的渲染到纹理策略加速锥束反投影计算,提高了圆弧轨迹Katsevich锥束CT重建算法的执行效率.在CPU中完成投影数据的滤波处理,并将其重排为四通道浮点纹理载人GPU内存;绑定2个浮点输出纹理到帧缓冲对象的不同绑定点,用于将渲染结果输出到纹理,并同时完成反投影数据的累加计算;将矩形网格编码为四叉树结构用于加速物体切片的绘制.实验结果表明,文中算法在较大锥角时仍能重建出高质量图像,并获得接近于实时的重建速度. 相似文献
106.
107.
近日,中国移动正式放号,启动TD-SCDMA试商用及友好用户测试。同时,第一批TD终端的价格方案也终于浮出水面。为鼓励消费者支持TD的试商用,中国移动此次对各款终端产品都给予了优厚的补贴。尤其是之前业界普遍看好的联想TD800手机更是爆出了1800元的超低价格,可见中国移动此次拓展TD业务的力度之大。据悉,与终端价格方案同时公布的,还有针对用户及渠道的不同优惠政策也同期出台。 相似文献
108.
Yueteng Gao Wei Li Boning Ou Shuhua Zhang Huwei Wang Junyang Hu Feiyu Kang Dengyun Zhai 《Advanced functional materials》2023,33(47):2305829
Potassium ion batteries using graphite anode and high-voltage cathodes are considered to be optimizing candidates for large-scale energy storage. However, the lack of suitable electrolytes significantly hinders the development of high-voltage potassium ion batteries. Herein, a dilute (0.8 m ) fluorinated phosphate electrolyte is proposed, which exhibits extraordinary compatibility with both graphite anode and high-voltage cathodes. The phosphate solvent, tris(2,2,2-trifluoroethyl) phosphate (TFP), has weak solvating ability, which not only allows the formation of robust anion-derived solid electrolyte interphase on graphite anode but also effectively suppresses the corrosion of Al current collector at high voltage. Meanwhile, the high oxidative stability of fluorinated TFP solvent enables stable ultrahigh-voltage (4.95 V) cycling of a potassium vanadium fluorophosphate (KVPO4F) cathode. Using TFP-based electrolyte, the 4.9 V-class potassium ion full cell based on graphite anode and KVPO4F cathode shows rather remarkable cycling performance with a high capacity retention of 87.2% after 200 cycles. This study provides a route to develop dilute electrolytes for high-voltage potassium ion batteries, by utilizing solvents with both weak solvating ability and high oxidative stability. 相似文献
109.
Qunping Fan Ruijie Ma Zhaozhao Bi Xunfan Liao Baohua Wu Sen Zhang Wenyan Su Jin Fang Chao Zhao Cenqi Yan Kai Chen Yuxiang Li Chao Gao Gang Li Wei Ma 《Advanced functional materials》2023,33(8):2211385
Here, a near-infrared (NIR)-absorbing small-molecule acceptor (SMA) Y-SeNF with strong intermolecular interaction and crystallinity is developed by combining selenophene-fused core with naphthalene-containing end-group, and then as a custom-tailor guest acceptor is incorporated into the binary PM6:L8-BO host system. Y-SeNF shows a 65 nm red-shifted absorption compared to L8-BO. Thanks to the strong crystallinity and intermolecular interaction of Y-SeNF, the morphology of PM6:L8-BO:Y-SeNF can be precisely regulated by introducing Y-SeNF, achieving improved charge-transporting and suppressed non-radiative energy loss. Consequently, ternary polymer solar cells (PSCs) offer an impressive device efficiency of 19.28% with both high photovoltage (0.873 V) and photocurrent (27.88 mA cm−2), which is one of the highest efficiencies in reported single-junction PSCs. Notably, ternary PSC has excellent stability under maximum-power-point tracking for even over 200 h, which is better than its parental binary devices. The study provides a novel strategy to construct NIR-absorbing SMA for efficient and stable PSCs toward practical applications. 相似文献
110.
Yuxiang Zhang Yangziyu Chen Yan Jiang Jing Wang Xiangyi Zheng Bo Han Kaisheng Xia Qiang Gao Zhao Cai Chenggang Zhou Ruimin Sun 《Advanced functional materials》2023,33(12):2212785
Heterostructure engineering is one of the most promising modification strategies for reinforcing Na+ storage of transition metal sulfides. Herein, based on the spontaneous hydrolysis-oxidation coupling reaction of transition metal sulfides in aqueous media, a VOx layer is induced and formed on the surface of VS2, realizing tight combination of VS2 and VOx at the nanoscale and constructing homologous VS2/VOx heterostructure. Benefiting from the built-in electric field at the heterointerfaces, high chemical stability of VOx, and high electrical conductivity of VS2, the obtained VS2/VOx electrode exhibits superior cycling stability and rate properties. In particular, the VS2/VOx anode shows a high capacity of 878.2 mAh g−1 after 200 cycles at 0.2 A g−1. It also exhibits long cycling life (721.6 mAh g−1 capacity retained after 1000 cycles at 2 A g−1) and ultrahigh rate property (up to 654.8 mAh g−1 at 10 A g−1). Density functional theory calculations show that the formation of heterostructures reduces the activation energy for Na+ migration and increases the electrical conductivity of the material, which accelerates the ion/electron transfer and improves the reaction kinetics of the VS2/VOx electrode. 相似文献