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51.
52.
Carl J. McHargue Joseph P. Hammond 《JOM Journal of the Minerals, Metals and Materials Society》1953,5(1):57-61
The wire textures for cold rolled and recrystallized iodide titanium and the sheet textures for this material produced by cold and hot rolling, and recrystallization at a series of temperatures were determined. The effect of the α → β transformation on the sheet texture was noted. 相似文献
53.
Carl Walding 《今日电子》2007,(3):73-74
节能设计正在席卷整个电子行业.电子设备的广泛使用对电网的压力越来越大,因此节能就显得非常有必要了. 政府机构和公用事业公司提出了一系列的法规和措施,来鼓励工程师开发效率更高的产品,尤其是在使用外置电源的时候.要满足这些法规,半导体公司将发挥关键作用,它们不断推出可降低待机功耗、提高效率的产品来达到法规的要求. 相似文献
54.
Iskander Magdy F. Maini Rajnish Durney Carl H. Bragg David G. 《IEEE transactions on bio-medical engineering》1981,(12):797-804
A numerical procedure to simulate several physiological and geometrical changes occurring during development of edema and to study their effects on the sensitivity of the microwave detection method is presented. The method of solution utilizes a model which consists of a two-dimensional cross section of a thorax. The model is based on an X-ray CAT scan taken with the microwave applicators in place. The electromagnetic boundary value problem is then solved numerically using the method of moments. Numerical results are presented to show the effects of several parameters, such as the uneven water distribution in the lung, the field distribution in the aperture of the microwave transmitter, and the location of the receiver on the sensitivity of the microwave detection method. Based on these results, several suggestions are made to help optimize the sensitivity of the microwave method of measuring changes in lung water content. 相似文献
55.
Richard Hartley Fredrik Kahl Carl Olsson Yongduek Seo 《International Journal of Computer Vision》2013,101(2):288-304
We consider the least-squares (L2) minimization problems in multiple view geometry for triangulation, homography, camera resectioning and structure-and-motion with known rotation, or known plane. Although optimal algorithms have been given for these problems under an L-infinity cost function, finding optimal least-squares solutions to these problems is difficult, since the cost functions are not convex, and in the worst case may have multiple minima. Iterative methods can be used to find a good solution, but this may be a local minimum. This paper provides a method for verifying whether a local-minimum solution is globally optimal, by providing a simple and rapid test involving the Hessian of the cost function. The basic idea is that by showing that the cost function is convex in a restricted but large enough neighbourhood, a sufficient condition for global optimality is obtained. The method is tested on numerous problem instances of real data sets. In the vast majority of cases we are able to verify that the solutions are optimal, in particular, for small to medium-scale problems. 相似文献
56.
Currently, quality estimation (QE) is mostly addressed using supervised learning approaches. In this paper we show that unsupervised and weakly supervised approaches (using a small training set) perform almost as well as supervised ones, for a significantly lower cost. More generally, we study the various possible definitions, parameters, evaluation methods and approaches for QE, in order to show that there are multiple possible configurations for this task. 相似文献
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59.
Hongqi Li Amit Misra Yuntian Zhu Zenji Horita Carl C. Koch Terry G. Holesinger 《Materials Science and Engineering: A》2009,523(1-2):60-64
Carbon nanotube (CNT) reinforced nanostructured Cu matrix composite with a grain size less than 25 nm has been successfully fabricated via a combination of ball milling and high-pressure torsion. CNTs were found to be homogeneously dispersed into the metal matrix, leading to grain refinement with a narrow grain size distribution and significant increase in hardness. 相似文献
60.
Prof. Dr. Andreas Leson Gregor Englberger Daniel Hammer Stefan Makowski Carl‐Friedrich Meyer Michael Leonhard Hans‐Joachim Scheibe Volker Weihnacht 《真空研究与实践》2015,27(4):24-28
Diamond‐like carbon thin films enhance efficiency — laser arc deposition of ta‐C Rising prices for fossil fuels as well as the increasing effects of the climate change due to the emission of greenhouse gases reveal the necessity of saving energy. Low friction coatings have an enormous potential in saving energy. Carbon based coatings — named as DLC coatings — are especially well suited for low friction coatings. In particular hydrogen‐free tetrahedral amorphous carbon (ta‐C) coatings are of great interest due to their extraordinary low wear properties. In addition they show excellent low friction properties and especially in combination with specific lubricants the so‐called super low friction effect. For the deposition of ta‐C coatings PVD methods have to be applied instead of CVD methods as it is the case for conventional DLC coatings. We have developed a deposition method which is based on a pulsed arc steered by a laser (Laser‐Arc). This allows us to use large cathodes resulting in a high long‐term stability. Furthermore, the carbon plasma source can be combined with a filtering unit removing almost all droplets and particles, which usually are characteristic for an arc process. The resulting Laser‐Arc source allows for the deposition of smooth and virtually defect‐free ta‐C coatings with a competitive deposition rate. 相似文献