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1.
2.
K. P. Seleznev Yu. B. Galerkin V. P. Mitrofanov M. R. Poles É. I. Sergacheva 《Chemical and Petroleum Engineering》1992,28(2):76-80
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 2, pp. 4–7, February, 1992. 相似文献
3.
B. P. Aduev É. D. Aluker A. G. Krechetov A. Yu. Mitrofanov 《Combustion, Explosion, and Shock Waves》2003,39(6):701-703
The velocity of the chain explosivedecomposition reaction in silver azide whiskes has been measured (1500 m/sec). The measured velocity is identified as the propagation velocity of the diffusion front of holes generated in the course of explosive decomposition. 相似文献
4.
Kabanov Alexander V.; Klyachko Natalya L.; Nametkin Sergei N.; Merker Steffen; Zaroza Anna V.; Bunik Vita I.; Ivanov Mikhail V.; Levashov Andrey V. 《Protein engineering, design & selection : PEDS》1991,4(8):1009-1017
The size of the inner water cavity of reversed micelles formedin a triple system water-surfactant-organic solventcan be widely varied by changing the degree of surfactant hydration.This gives grounds to use reversed micelles as matrix microreactorsfor the design of supramolecular complexes of proteins. Usingultracentrifugation analysis, it has been demonstrated thatthe oligomeric composition of various enzymes (ketoglutaratedehydrogenase, alkaline phosphatase, lactic dehydrogenase, glyceraldehyde-3-phosphatedehydrogenase) solubilized in reversed micelles of Aerosol OT[sodium bis(2-ethylehexyl)sulfosuccinate] in octane changesupon variation of the degree of hydration. An oligomeric complexforms under conditions when the radius of the micelle innercavity is big enough to incorporate this complex as a whole.At lower degrees of hydration the micelles uncouplesuch complexes to their components. The catalytic propertiesof various oligomeric complexes have been studied. Possibilitiesof using reversed micelles for the separation of subunits ofoligomeric enzymes under non-denaturating conditions have beendemonstrated. In particular, the isolated subunits of alkalinephosphatase, lactic dehydrogenase and glyceralde-hyde-3-phosphatedehydrogenase have been found to be active in Aerosol OT reversedmicelles. The dependences of the catalytic activity of oligomericenzymes represent saw-like curves. The maxima of the catalyticactivity observed at these curves relate to the functioningof various oligomeric forms of an enzyme. The radii of the micelleinner cavity under conditions when these maxima are observedcorrelate with the linear dimensions of the enzyme oligomericforms. Correlation of the position of a maximum with the shapeof an oligomeric complex is discussed. 相似文献
5.
Mitrofanov A. N. 《Power Technology and Engineering (formerly Hydrotechnical Construction)》1994,28(4):239-242
1. | The design scheme of the 500-kV OEE of the Sayano-Shushenskoe hydrostation has a number of substantial shortcomings reducing the reliability of power output. Reconstruction of the middle network of the existing 4/3 scheme to three networks with two switches per connection is the most optimal variant of reconstruction. Sectioning of the collecting bus systems is necessary for a further increase of the reliability of the scheme. |
2. | In the case of repair works on equipment of small nonstandard switchgear, such as the 500-kV OEE of the Sayano-Shushenskoe hydrostation, it is necessary to use special equipment and mechanisms, the development of which must be recommended to domestic industry. |
6.
Composite Materials Based on Shape‐Memory Ti2NiCu Alloy for Frontier Micro‐ and Nanomechanical Applications 下载免费PDF全文
7.
Fan Yang Mikel Abadia Chaoqiu Chen Weike Wang Le Li Lianbing Zhang Celia Rogero Andrey Chuvilin Mato Knez 《Nano Research》2017,10(1):97-107
The oxygen reduction reaction (ORR) is essential in research pertaining to life science and energy. In applications, platinum-based catalysts give ideal reactivity, but, in practice, are often subject to high costs and poor stability. Some cost-efficient transition metal oxides have exhibited excellent ORR reactivity, but the stability and durability of such alternative catalyst materials pose serious challenges. Here, we present a facile method to fabricate uniform Co x O y nanoparticles and embed them into N-doped carbon, which results in a composite of extraordinary stability and durability, while maintaining its high reactivity. The half-wave potential shows a negative shift of only 21 mV after 10,000 cycles, only one third of that observed for Pt/C (63 mV). Furthermore, after 100,000 s testing at a constant potential, the current decreases by only 17%, significantly less than for Pt/C (35%). The exceptional stability and durability results from the system architecture, which comprises a thin carbon shell that prevents agglomeration of the Co x O y nanoparticles and their detaching from the substrate. 相似文献
8.
Summary Using a bead spring model of flexible polymer chains, the density profiles and chain configurational properties of polymer solutions confined between parallel plates were studied. A wide range of density , chain length N, and strength of a short-range attractive wall potential was investigated. Both a temperature T in the good solvent regime (T > , being the Theta temperature where a chain in unconfined bulk three-dimensional solution would behave ideally) and a temperature in the bad solvent regime (T < ) were considered. It is shown that phase separation in a polymer-rich and polymer-poor solution in the slit competes with polymer adsorption at the walls. A qualitative connection to the wetting behavior of semi-infinite polymer solutions is drawn. The acceptance rate for monomer motions was studied for various conditions, and profiles of monomer mobility across the slit were recorded. Also, average chain relaxation times were extracted from the time dependence of mean-square displacements. Although with increasing density the chain radii (at T > ) show a crossover from two-dimensional excluded volume behavior (Rg N2 with = 3/4) to ideal random walk behavior ( = 1/2), the relaxation times show effective exponents Zeff ( NZ
eff) that clearly deviate from the Rouse prediction in concentrated confined solutions. 相似文献
9.
Kaushik Deb Andrey Vavilin Jung-Won Kim Kang-Hyun Jo 《International Journal of Control, Automation and Systems》2010,8(5):975-984
Tilt correction is a very crucial and inevitable task in the automatic recognition of the vehicle license plate (VLP). In
this paper, according to the least square fitting with perpendicular offsets (LSFPO), the VLP region is fitted to a straight
line. After the line slope is obtained, rotation angle of the VLP is estimated. Then the whole image is rotated for tilt correction
in horizontal direction by this angle. Tilt correction in vertical direction by minimizing the variance of coordinates of
the projection points is proposed. Character segmentation is performed after horizontal correction and character points are
projected along the vertical direction after shear transform. Despite the success of VLP detection approaches in the past
decades, a few of them can effectively locate license plate (LP), even when vehicle bodies and LPs have similar color. A common
drawback of color-based VLP detection is the failure to detect the boundaries or border of LPs. In this paper, we propose
a modified recursive labeling algorithm for solving this problem and detecting candidate regions. According to different colored
LP, these candidate regions may include LP regions. Geometrical properties of the LP such as area, bounding box and aspect-ratio
are then used for classification. Various LP images were used with a variety of conditions to test the proposed method and
results are presented to prove its effectiveness. 相似文献
10.
This paper describes a cluster-based method for combining differently exposed images in order to increase their dynamic range. Initially an image is decomposed into a set of arbitrary shaped regions. For each region we compute a utility function which is based on the amount of presented information and an entropy. This function is used to select the most appropriate exposure for each region. After the exposures are selected, a bilateral filtering is applied in order to make the interregional transitions smooth. As a result we obtain weighting coefficients for each exposure and pixel. An output image is combined from clusters of input images using weights. Each pixel of the output image is calculated as a weighted sum of exposures. The proposed method allows recovering details from overexposed and underexposed parts of image without producing additional noise. Our experiments show effectiveness of the algorithm for the high dynamic range scenes. It requires no information about shutter speed or camera parameters. This method shows robust results even if the exposure difference between input images is 2-stops or higher. 相似文献