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91.
作者以不同功率的氮澈光对大白鼠分组进行穴位照射。照射前后测痛,照射后动物痛阈都有提高,说明不同功率的氮激光均有镇痛作用。高、低功率氮澈光穴位照射后动物产生的痛阈变化经统计学处理,差异性不显著。提示使用低功率氮激光同样可达提高痛阈的目的。 相似文献
92.
根据Kretschmann型表面等离子共振传感系统的需要进行设计,实现基于C51单片机,包括上位机、4×4键盘和1602液晶功能等多种用户交互方式的硬件控制系统。使用C语言编写单片机控制程序,实现键盘和液晶显示操作控制功能,并操作步进电机进而控制传感器入射光角度,还通过串口转RS485控制泵和阀进而精确控制样品的注入。上位机上编写了与单片机通信的Labview串口通信程序,单片机接收处理指令,实现了上位机上的传感器入射光角度控制。提供了全面易用的表面等离子共振传感器系统功能。 相似文献
93.
94.
针对高功率微波(high-power microwave,HPM)及其相关技术研究的过程中会产生复杂强电磁环境的问题,构建一种对抗复杂电磁环境,排除强辐射源影响总能够正常可靠工作的电子信息综合测控系统.采用全光纤通信的架构,不仅提高了控制系统的电磁兼容能力,而且增加了信号的传输距离;利用集中管理、分散控制的远程分布式控制体系,使整个控制系统分化为多个控制模块,各控制模块控制功能相对独立,通过PXI现场总线实现数据共享.分析结果表明:该系统提高了控制系统的可靠性和灵活性,降低了控制系统的复杂性,为具有高可靠的HPM测控系统的设计提供了有效的技术途径. 相似文献
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96.
Microfluidic fuel cell (MFC) suffers from small single cell output power due to the inherent cell size limitation as microscale geometries are prerequisite to prevent reactant crossover between the anode and cathode. To meet the power demand of practical applications, previous works mainly focus on the creating of MFC stacks with multiple cells connected in series, parallel, or mixture of both series and parallel to increase the output power. Yet, low energy efficiency is observed because of the flow distribution nonuniformity and shunt current losses. In this work, a high performance radial vanadium redox MFC is presented to address the size limitation issue by adding a separate layer between the porous electrodes of the conventional plate‐frame MFC. Specific cell characteristics are detailed by mathematical modeling, and parametric studies are performed to evaluate the influences of the geometrical and operational parameters on the cell performance. The results show that this new radial MFC can provide a higher fuel utilization and meanwhile an improved cell performance under a fixed electrode size compared with the conventional plate‐frame MFC. Moreover, the electrode size limitation due to the reactant crossover between the anode and cathode is broken as the influences of the electrode size on the mixing region are greatly reduced. In the case with the electrode size equal to 18 mm × 18 mm , single cell output power of 0.35 mW with a fuel utilization of 53.33% is obtained under the reactant concentration of 2 mol L?1 and flow rate of 300 μL min?1 . 相似文献
97.
Nanofluids with high thermal conductivity coefficient are introduced to the thermal management system of power battery packs for electric vehicles and hybrid electric vehicles. Two typical cooling structures of cylindrical and square battery packs are described, and their flow models are established. By similarity transformations, the nonlinear system of partial differential equations is reduced and then solved numerically by the shooting method. The heat transfer properties of three types of nanofluids, that is, CuO‐EG, Al2O3‐EG, TiO2‐EG, are analyzed in detail. It is found that CuO‐EG nanofluid is the best coolant for the cylindrical battery pack, whereas Al2O3‐EG nanofluid is the best choice for square battery pack cooling. 相似文献
98.
Zwitterionic materials have moieties possessing cationic and anionic groups. This molecular structure leads to unique properties that can be the solutions of various application problems. A typical example is that zwitterionic carboxybetaine (CB) and sulfobetaine (SB) materials resist nonspecific protein adsorption in complex media. Considering the vast number of cationic and anionic groups in the current chemical inventory, there are many possible structural variations of zwitterionic materials. The diversified structures provide the possibility to achieve many desired properties and urge a better understanding of zwitterionic materials to provide design principles. Molecular simulations and modeling are a versatile tool to understand the structure–property relationships of materials at the molecular level. This progress report summarizes recent simulation and modeling studies addressing two fundamental questions regarding zwitterionic materials and their applications as biomaterials. First, what are the differences between zwitterionic and nonionic materials? Second, what are the differences among zwitterionic materials? This report also demonstrates a molecular design of new protein‐resistant zwitterionic moieties beyond conventional CB and SB based on design principles developed from these simulation studies. 相似文献
99.
本文针对数据需求分析中存在的问题,提出了一种数据需求分析方法、数据需求分析步骤,及在湖南省电力负荷管理系统中的应用。 相似文献
100.
Bowen Li Zhefan Yuan Peng Zhang Andrew Sinclair Priyesh Jain Kan Wu Caroline Tsao Jingyi Xie Hsiang‐Chieh Hung Xiaojie Lin Tao Bai Shaoyi Jiang 《Advanced materials (Deerfield Beach, Fla.)》2018,30(14)
For biotherapeutics that require multiple administrations to fully cure diseases, the induction of undesirable immune response is one common cause for the failure of their treatment. Covalent binding of hydrophilic polymers to proteins is commonly employed to mitigate potential immune responses. However, while this technique is proved to partially reduce the antibodies (Abs) reactive to proteins, it may induce Abs toward their associated polymers and thus result in the loss of efficacy. Zwitterionic poly(carboxybetaine) (PCB) is recently shown to improve the immunologic properties of proteins without inducing any antipolymer Abs against itself. However, it is unclear if the improved immunologic profiles can translate to better clinical outcomes since improved immunogenicity cannot directly reflect amelioration in efficacy. Here, a PCB nanocage (PCB NC) is developed, which can physically encase proteins while keeping their structure intact. PCB NC encapsulation of uricase, a highly immunogenic enzyme, is demonstrated to eradicate all the immune responses. To bridge the gap between immunogenicity and efficacy studies, the therapeutic performance of PCB NC uricase is evaluated and compared with its PEGylated counterpart in a clinical‐mimicking gouty rat model to determine any loss of efficacy evoked after five administrations. 相似文献