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61.
CNG(压缩天然气)作为当今汽车能源的重要组成部分,凭借其污染小、经济性好、成本低等优势得到迅速推广,CNG汽车市场占有率越来越大,CNG加气站的需求量也日益增加。根据《汽车加油加气站设计与施工规范》,对某CNG加气站进行初步设计,并结合国内外CNG加气站安全风险评价技术,采取科学、系统、完善的方针,对该CNG加气站进行安全风险评价。 相似文献
62.
在未来的通信领域中,全光逻辑门是全光计算机和全光网络的基本单元。目前已经提出了很多实现全光逻辑门的结构和方法,但是全光逻辑的技术瓶颈也出现了,就是怎样能够将单个的全光逻辑门级联起来实现更复杂的逻辑关系。现存的全光逻辑门结构一般不具有很好的可以实现多级连接的级联性,而且现有的对于级联性的分析大都停留在理论层面,而没有与实际情况相结合,所以对于实际应用来说意义很小。提出了一种新型的基于高非线性Sagnac 干涉仪的超高速全光NOT 门,建立了它的数学模型,采用了与实际情况更加接近的高斯脉冲模拟输入光,并且在仿真结果的基础上分析了系统的级联性,对级联性的分析考虑了光纤损耗和走离效应的影响。得到的基本结论表明,所提出的全光逻辑门的结构能够在实际情况下保持良好的级联性。 相似文献
63.
水利水电工程网络进度计划是施工组织设计的重要组成部分。针对目前大多数网络进度计划软件在进度计划生成、分析等方面提供的功能有限,使得网络进度计划编制费时、费力,效率不高,且标准化程度不高等问题,本文在分析了水利水电工程网络进度计划标准化内涵的基础上,对网络进度计划标准化的基本内容进行了研究;在此基础上设计开发了水利水电工程网络进度计划标准化系统,详细介绍了网络进度计划辅助生成、分析、评价与审阅,以及成果输出等功能。该系统不仅界面友好、直观可视化,而且提供了强大的计算及优化功能,大大提高了工程人员网络进度计划编制的效率和质量,为网络进度计划快速分析和优化提供了一种新的思路和手段。 相似文献
64.
《Current Opinion in Solid State & Materials Science》2015,19(5):277-286
Surface modification of structural and functional materials under bombardment by energetic ions is observed under different conditions and can be either an unavoidable effect of the irradiation or an intentional modification to enhance materials properties. Understanding the basic mechanisms is necessary for predicting property changes. The mechanisms activated during ion irradiation are of atomic scale and atomic scale modeling is the most suitable tool to study these processes. In this paper, we present results of an extensive simulation program aimed at developing an understanding of primary surface damage in iron induced by energetic particles. We simulated 25 keV self-ion bombardment of Fe thin films with (1 0 0) and (1 1 0) surfaces at room temperature. A large number of simulations, ∼400, were carried out allow a statistically significant treatment of the results. The particular mechanism of surface damage depends on how the destructive supersonic shock wave generated by the displacement cascade interacts with the free surface. Three scenarios were primarily observed, with the limiting cases being damage created far below the surface with little or no impact on the surface itself, and extensive direct surface damage on the timescale of a few picoseconds. In some cases, formation of large 〈1 0 0〉 vacancy loops beneath the free surface was observed, which may explain some earlier experimental observations. 相似文献
65.
66.
Real‐Time License Plate Detection in High‐Resolution Videos Using Fastest Available Cascade Classifier and Core Patterns 下载免费PDF全文
We present a novel method for real‐time automatic license plate detection in high‐resolution videos. Although there have been extensive studies of license plate detection since the 1970s, the suggested approaches resulting from such studies have difficulties in processing high‐resolution imagery in real‐time. Herein, we propose a novel cascade structure, the fastest classifier available, by rejecting false positives most efficiently. Furthermore, we train the classifier using the core patterns of various types of license plates, improving both the computation load and the accuracy of license plate detection. To show its superiority, our approach is compared with other state‐of‐the‐art approaches. In addition, we collected 20,000 images including license plates from real traffic scenes for comprehensive experiments. The results show that our proposed approach significantly reduces the computational load in comparison to the other state‐of‐the‐art approaches, with comparable performance accuracy. 相似文献
67.
68.
Shari Sellers Walter Horodnik Aileen House Jennifer Wylie Peter Mauser Natalie Garber 《Drug development and industrial pharmacy》2015,41(12):1989-1996
AbstractContext: Aerosol delivery to animals in preclinical settings has historically been very challenging, requiring the use of techniques, such as intratracheal instillation and dry powder insufflation, that are somewhat invasive, inefficient and not representative of clinical inhalation.Objective: The objective of this work is to develop a system to deliver dry powder to dogs in an efficient and effective manner for the study of new anti-migraine compounds in development.Materials and methods: The new device uses a metered aliquot of a dry gas to force dry powder drug from a pre-filled HPMC capsule into an AeroChamber® spacer for subsequent inhalation by the animal.Results: The delivery of two invesigational migraine drugs via the new device was assessed in vitro using abbreviated Andersen cascade impaction and showed the device is capable of generating a reproducible delivered dose of up to ~68% with more than 50% of the dose in the respirable range. In vivo studies have also been performed showing that this device effectively delivered the migraine drugs to spontaneously breathing dogs using a proprietary validated dog inhalation model.Discussion: Results confirmed that the air pressurized capsule device (APCD) was effective in delivering the APIs to lungs of the animals. The in vivo data verified the advantages of inhaled delivery over oral delivery for this class of drugs and were used to establish the cardiopulmonary and respiratory side effect liability profile for these compounds.Conclusions: This work has demonstrated the utility of this device for quick and accurate screening of prospective drug candidates, representing a significant improvement in ease of use and reprodicibility over current delivery methods. 相似文献
69.
70.
水电站混凝土大坝局部裂缝是常见的混凝土缺陷之一。本文介绍了湖北利川某电站混凝土大坝裂缝的普查分类和针对不同类别裂缝的处理工艺,对于浅层裂缝采用水泥基渗透结晶型防水材料涂刷,对于不渗水或渗水量较小的裂缝采用环氧树脂灌浆+环氧胶泥涂刷,对于渗水量较大的裂缝采用聚氨酯灌浆+环氧胶泥涂刷。上述处理方法可为水工建筑物混凝土裂缝处理提供借鉴和参考。 相似文献