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161.
Erich Eder 《国际钢铁研究》1968,39(2):113-117
Gleichungssystem. Zwei Stoffflußmodelle. Näherung für die spezifische Normalkraft in der Grenzschicht. Anwendung prismatischer Stauchkörper, Walzen auf flacher Bahn. 相似文献
162.
G
2 interpolation and blending on surfaces 总被引:3,自引:0,他引:3
Erich Hartmann 《The Visual computer》1996,12(4):181-192
We introduce a method for curvature-continuous (G
2) interpolation of an arbitrary sequence of points on a surface (implicit or parametric) with prescribed tangent and geodesic curvature at every point. The method can also be used forG
2 blending of curves on surfaces. The interpolation/blending curve is the intersection curve of the given surface with a functional spline (implicit) surface. For the construction of blending curves, we derive the necessary formulas for the curvature of the surfaces. The intermediate results areG
2 interpolation/blending methods in IR2. 相似文献
163.
Fabian Duddeck Stephan Hunkeler Pablo Lozano Erich Wehrle Duo Zeng 《Structural and Multidisciplinary Optimization》2016,54(3):415-428
Although topology optimization is well established in most engineering fields, it is still in its infancy concerning highly non-linear structural applications like vehicular crashworthiness. One of the approaches recently proposed and based on Hybrid Cellular Automata is modified here such that it can be applied for the first time to thin-walled structures. Classical methods based on voxel techniques, i.e., on solid three-dimensional volume elements, cannot derive structures made from thin metal sheets where the main energy absorption mode is related to plastic buckling, folding and failure. Because the main components of car structures are made from such thin-walled beams and panels, a special approach using SFE CONCEPT was developed, which is presented in this paper. 相似文献
164.
165.
Schneider E Keller M Brennauer A Hoefelschweiger BK Gross D Wolfbeis OS Bernhardt G Buschauer A 《Chembiochem : a European journal of chemical biology》2007,8(16):1981-1988
Cyanine-5-labelled neuropeptide Y (NPY) was demonstrated to be an ideal universal fluorescent ligand for the combined investigation of NPY Y(1), Y(2) and Y(5) receptors. With respect to improved stability, detection of receptor subtypes in cells and tissues, and prevention of receptor internalization, small nonpeptidic fluorescent antagonists should be superior. Here we present a set of four fluorescent nonpeptide NPY Y(1) receptor (Y(1)R) antagonists. The highest affinity was obtained by labelling an N(G)-(6-aminohexanoyl)argininamide derived from the Y(1)R antagonist BIBP 3226, with Py-1, a small pyrylium dye. The fluorescent pyridinium-type Y(1)R antagonist, compound 4 had K(i) values of 29 nM and 2.7 nM, which were determined by radioligand binding and flow cytometry under equilibrium conditions, respectively; 4 had a K(b) value of 0.6 nM (Ca(2+) assay). The large Stoke's shift (541 vs. 615 nm) in buffer (PBS, pH 7.4) in the presence of 1% BSA and the red emission (quantum yield 56%) are advantageous with respect to the signal-to-noise ratio. The new probe was successfully used in fluorescence-based binding experiments evaluated by flow cytometry and confocal microscopy; this demonstrates the potential of pyrylium dyes for the preparation of fluorescent ligands that are applicable for the study of G protein-coupled receptors on living cells. 相似文献
166.
The process parameters of atmospheric plasma spraying (APS) influence the coating formation and properties of partially yttria
stabilized zirconia (PYSZ) thermal barrier coatings (TBC). Simulations can be used to investigate this dependency and to design
the coating process for a targeted production of TBCs. A whole process simulation was realized by modeling the linked subprocesses:
plasma torch, plasma free jet, powder particles characteristics, and coating formation. The coating formation can be described
by model approaches with different physical assumptions and geometric scales. One approach is the simulation of single powder
particles hitting the substrate surface. An alternative macroscale finite element model (FEM) model approach is applied in
the coating formation simulation. A group of particles is pooled in a splash that is dependent on the precalculated particle
distribution in front of the substrate. A third modeling approach is applied to calculate effective mechanical and thermodynamical
properties of coatings dependent on the experimentally obtained or calculated microstructure of the PYSZ TBC, which is based
on different homogenization methods. The application of three simulation approaches in the whole process simulation of APS
is discussed; advantages and disadvantages are elucidated. Results based on simulation and experiments are presented for a
variation of process parameters. Missing links in the multiscale approach are detected to make suggestions for future modeling
and simulation work.
This article was originally published inBuilding on 100 Years of Success, Proceedings of the 2006 International Thermal Spray Conference (Seattle, WA), May 15–18, 2006, B.R. Marple, M.M. Hyland, Y.-Ch. Lau, R.S. Lima, and J. Voyer, Ed., ASM International, Materials
Park, OH, 2006. 相似文献
167.
A Combined Surface Science and Electrochemical Study of Tungsten Carbides as Anode Electrocatalysts 总被引:1,自引:0,他引:1
Erich C. Weigert Michael B. Zellner Alan L. Stottlemyer Jingguang G. Chen 《Topics in Catalysis》2007,46(3-4):349-357
An effective anode electrocatalyst in direct methanol fuel cell (DMFC) should have high activity for the oxidation of methanol
and the decomposition of water, while remaining stable under the relatively harsh anode environment. Although the Pt/Ru bimetallic
alloy is currently the most effective anode electrocatalyst, both Pt and Ru are expensive due to limited supplies and both
are susceptible to CO poisoning. Consequently, the discovery of less expensive and more CO tolerant alternatives to the Pt/Ru
catalysts would help facilitate the commercialization of DMFC. In this paper we will discuss the possibility of using tungsten
carbides (WC) and Pt-modified WC as potential anode electrocatalysts in DMFC. We will provide an overview of our recent work,
using a combined approach of fundamental surface science studies and in-situ electrochemical evaluation of the activity and
stability of tungsten carbides. We will demonstrate the feasibility to bridge fundamental surface science studies on single
crystals with the electrochemical evaluation on polycrystalline WC films. We will also discuss the synergistic effect by supporting
low coverages of Pt on the WC substrate to further enhance the electrochemical performance of WC. 相似文献
168.
169.
Byun H Sander MY Motamedi A Shen H Petrich GS Kolodziejski LA Ippen EP Kärtner FX 《Applied optics》2010,49(29):5577-5582
We demonstrate a high-repetition-rate soliton fiber laser that is based on highly doped anomalously dispersive erbium-doped fiber. By splicing an 11 mm single-mode fiber to the erbium-doped fiber, the thermal damage of the butt-coupled saturable Bragg reflector (SBR) is overcome. The laser generates 187 fs pulses at a repetition rate of 967 MHz with a measured long-term stability of more than 60 h. 相似文献
170.
Near equilibrium, the rate of relaxation to equilibrium and the transport properties of excitations (bogolons) in a dilute Bose-Einstein condensate (BEC) are determined by three collision integrals, , , and . All three collision integrals conserve momentum and energy during bogolon collisions, but only conserves bogolon number. Previous works have considered the contribution of only two collision integrals, and . In this work, we show that the third collision integral makes a significant contribution to the bogolon number relaxation rate and needs to be retained when computing relaxation properties of the BEC. We provide values of relaxation rates in a form that can be applied to a variety of dilute Bose-Einstein condensates. 相似文献