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21.
Walter Michaeli Dirk Opfermann Thomas Kamps 《The International Journal of Advanced Manufacturing Technology》2007,33(1-2):206-211
In micro systems technology, the process of micro assembly injection moulding is used for the generation of hybrid micro systems.
With this process, more functions are integrated in less space. In the field of medical technology, miniaturisation also means
new methods of treatment with fewer side effects on the patient. New cures are developed by the miniaturisation of medical
instruments, such as keyhole surgery. For detailed investigations a specific demonstration was developed to display the potential
of micro assembly injection moulding in medical science. This part consists of a carbon-fibre reinforced PEEK puncture needle,
which incorporates three lumens. The selected materials allow use of the needle during magnetic resonance imaging. In order
to attach additional equipment a plastic connector needs to be overmoulded on the needle. The investigations focus on the
injection moulding process by characterising the influences of temperature, moulding parameters and material combinations
on the resulting bond strength between needle and connector. 相似文献
22.
S. von Molnár 《Journal of Superconductivity》2003,16(1):1-5
This presentation will review physical properties, relevant to spintronics, of concentrated magnetic semiconductors. Examples from the open literature and current research utilizing thin film EuS will be used as illustrations. New research on potential spin injection materials and spin detection will also be described. This latter work, carried out at MARTECH, the Center for Materials Research and Technology, demonstrates that carriers from the half-metal CrO2 may be injected across an insulator without loss of (100%) spin polarization. It also features the development of a Hall gradiometer capable of detecting as few as 105 spins. 相似文献
23.
通过运用Moldnow软件对数码相机面壳注射成型进行了流动模拟分析,预测在不同浇口位置和数目的情况下可能存在的气泡和熔接痕位置,确定了最佳的浇口数目和位置. 相似文献
24.
In the light of fractal geometry theory, the characteristics of coal's electric parameters (including dielectric constant, alternating conductivity, dielectric loss angle tangent and electric polarization constant) were studied by using literature data. The results are shown that the electrical properties of coal have fractal characteristic. The fractal dimensions of dielectric, alternating conductivity, dielectric loss angle tangent were obtained, and are relative to the content of pyrite sulfur, heat and ash content of coal. 相似文献
25.
The difficulty of selecting appropriate rheological model and parameters for the alternating distribution of soft and hard rock layers was often encountered due to the unhomogeneity, discontinuity and anisotropy of rock mass. The Burgers and generalized Kelvin models were applied to the soft and hard rock respectively and the rheological parameters were obtained based on the method of optimum separation. By using the simulated code FLAC^3D, the stability of surrounding rocks of a certain underground plant was analyzed. The effect of surface load and weakening the parameters intensity of argillaceous and bioclastic interlayers between soft and hard rock on rheological behavior of layer composite rock mass was investigated. The results indicate that the rheological characteristics of soft and hard rock layer in composite rock mass can be described well with above two rheological models. 相似文献
26.
在高冶强的生产状态下,高炉如何优化各项技术经济指标,降低其成本,从而提高产品竞争力,是现代高炉操作者积极探索的问题。梅钢2号高炉通过精料、优化操作、改进工艺措施等的实施,实现了高炉高冶强下的指标优化。 相似文献
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29.
研究了Windows操作系统下的一种木马检测技术,该木马结合了远程线程注入、动态链接库(DLL)等技术。针对目前最新的远程线程注入实现木马隐藏的关键技术,提出了一种进程被远程注入动态链接库的检测方法和相应动态链接库的卸载方法。实验表明,这种方法对已被远程线程注入DLL的进程检测和恢复效果明显。 相似文献
30.
Copper MOCVD (metalorganic chemical vapor deposition) using liquid injection for effective delivery of the (hfac)Cu(vtmos)
[1,1,1,5,5,5-hexafluoro-2,4-pentadionato(vinyltrimethoxysilane) copper(I)] precursor has been performed to clarify growth
behavior of copper films onto TiN, <100> Si, and Si3N4 substrates. Especially, we have studied the influences of process conditions and the substrate on growth rates, impurities,
microstructures, and electrical characteristics of copper films. As the reactor pressure was increased, the growth rate was
governed by a pick-up rate of (hfac)Cu(vtmos) in the vaporizer. The apparent activation energy for copper growth over the
surface-reaction controlled regime from 155°C to 225°C was in the range 12.7–32.5 kcal/mol depending upon the substrate type.
It revealed that H2 addition at 225°C substrate temperature brought about a maximum increase of about 25% in the growth rate compared to pure
Ar as the carrier gas. At moderate deposition temperatures, the degree of a <111> preferred orientation for the deposit was
higher on the sequence of <Cu/Si<Cu/TiN<Cu/Si3N4. The relative impurity content within the deposit was in the range 1.1 to 1.8 at.%. The electrical resistivity for the Cu
films on TiN illustrated three regions of the variation according to the substrate temperature, so the deposit at 165°C had
the optimum resistivity value. However, the coarsened microstructures of Cu on TiN prepared above 275°C gave rise to higher
electrical resistivities compared to those on Si and Si3N4 substrates. 相似文献