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131.
O. Hölck J. Bauer O. Wittler B. Michel B. Wunderle 《Microelectronics Reliability》2012,52(7):1285-1290
An investigation of interfacial interaction has been performed between three epoxy molding compound materials and a native silicon dioxide layer (SiO2) usually found at chip surfaces. The epoxy materials were an industry oriented epoxy molding compound Epoxy Phenol Novolac (EPN), its filled variety EPNF (with silica particles) and a model aromatic epoxy1 (2 1 2). All systems are described in full in [1] and [2]. The free surfaces of the solid materials were experimentally analyzed by contact angle measurements of three different liquids (water, methylene-iodide (MI) and glycerol). Results are compared to interfacial energies obtained by analysis of the interfaces in bimaterial molecular models, yielding reasonable agreement. A qualitative prediction regarding the influence of water on the interfacial strength between chip and molding compound is attempted. 相似文献
132.
133.
Leopold Weber Wolfgang Lenhardt Franz Möstl Gregor Götzl Julia Weilbold Heinz Reitner 《BHM Berg- und Hüttenm?nnische Monatshefte》2016,161(4):148-155
Touristic mines are by far not only of public interest. During guided tours the importance of mining and mineral resources for society can be explained in a proper way. Mineral deposits, for long time not accessible and only known from old literature can now be studied in detail by scientists. Old underground mines can be used for different purposes. With respect to Arzberg the different possibilities of utilization of old underground workings are described in detail: A touristic mine serves not only as an attraction, but also as a training centre for underground geological mapping, geochemistry and geophysics research laboratory of universities. For many years the ZAMG (Central Institute for Meteorology and Geodynamics) has been operating a seismic station, and parts of the old mine workings have been used for cheese refinery since 2006. Furthermore, the mine water is utilized for extracting geothermal energy and serves the cooling chambers. The combined use of the old mine workings by different parties permits sharing the substantial maintenance costs. 相似文献
134.
Riener Heinz Haedicke Finn Frehse Stefan Soeken Mathias Große Daniel Drechsler Rolf Fey Goerschwin 《International Journal on Software Tools for Technology Transfer (STTT)》2017,19(5):605-621
International Journal on Software Tools for Technology Transfer - Many applications from artificial intelligence and formal methods use decision procedures as their core solving engines. In this... 相似文献
135.
Colaianni Matteo Siegl Christian Süßmuth Jochen Bauer Frank Greiner Günther 《计算可视媒体(英文)》2017,3(4):305-313
Computational Visual Media - We present a novel approach to mesh deformation that enables simple context sensitive manipulation of 3D geometry. The method is based on locally anisotropic... 相似文献
136.
M. Bauer T. Schilling M. Weidling D. Hartung Ch. Biskup P. Wriggers F. Wacker Fr. -W. Bach A. Haverich T. Hassel 《Journal of materials science. Materials in medicine》2014,25(3):909-916
Synthetic patch materials currently in use have major limitations, such as high susceptibility to infections and lack of contractility. Biological grafts are a novel approach to overcome these limitations, but do not always offer sufficient mechanical durability in early stages after implantation. Therefore, a stabilising structure based on resorbable magnesium alloys could support the biological graft until its physiologic remodelling. To prevent early breakage in vivo due to stress of non-determined forming, these scaffolds should be preformed according to the geometry of the targeted myocardial region. Thus, the left ventricular geometry of 28 patients was assessed via standard cardiac magnetic resonance imaging (MRI). The resulting data served as a basis for a finite element simulation (FEM). Calculated stresses and strains of flat and preformed scaffolds were evaluated. Afterwards, the structures were manufactured by abrasive waterjet cutting and preformed according to the MRI data. Finally, the mechanical durability of the preformed and flat structures was compared in an in vitro test rig. The FEM predicted higher durability of the preformed scaffolds, which was proven in the in vitro test. In conclusion, preformed scaffolds provide extended durability and will facilitate more widespread use of regenerative biological grafts for surgical left ventricular reconstruction. 相似文献
137.
R. Bauer B. F. Rheingans E. J. Mittemeijer 《Metallurgical and Materials Transactions A》2011,42(7):1750-1759
The kinetics of the precipitation of Co from a supersaturated solid solution of Cu-0.95 at. pct Co was investigated by isochronal
annealing applying differential scanning calorimetry (DSC) with heating rates in the range 5 to 20 K min–1. The corresponding microstructural evolution was investigated by high-resolution transmission electron microscopy (HRTEM)
in combination with electron energy loss spectroscopy (EELS). Upon isochronal annealing, spherical Co precipitates of fcc
crystal structure form. Kinetic analysis by fitting of a modular phase transformation model to, simultaneously, all DSC curves of variable heating rate measured for Cu-0.95 at. pct Co showed that the precipitation-process mechanism
can be described within the framework of this general phase transformation model by continuous nucleation and diffusion-controlled
growth. By introducing additional microstructural information (here, the precipitate-particle density), for the first time,
values for the separate activation energies of nucleation and growth could be deduced from the transformation kinetics. 相似文献
138.
A mathematical model was used to study the effect of slip between the gas and liquid phases on the performance of an electrochemical fluorination reactor. The model incorporates two-phase flow with differential material, energy and pressure balances. The effect of slip on the temperature, pressure, gas fraction and current distribution in the reactor is presented under relatively severe operating conditions. In addition, the effect of slip on the cell voltage, current efficiency and energy usage is shown at different flow rates over a wide current range. It was found that slip of the gas past the liquid is insignificant under normal operating conditions, but it is significant at high cell currents and low flow rates. Under these more severe operating conditions, slip significantly reduces the cell voltage, and hence the energy usage, since less gas resides in the reactor. 相似文献
139.
Heinz E. May T. Born D. Zieger G. Anders S. Zakosarenko V. Meyer H.-G. Schäffel C. 《Journal of Infrared, Millimeter and Terahertz Waves》2015,36(10):879-895
Journal of Infrared, Millimeter, and Terahertz Waves - Passive submillimeter-wave imaging is a concept that has been in the focus of interest as a promising technology for personal security... 相似文献
140.