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81.
Cho Younghee; Luce R. Duncan; von Winterfeldt Detlof 《Canadian Metallurgical Quarterly》1994,20(5):931
A rank- and sign-dependent utility theory is based on an operation of joint receipt of 2 independent gambles and 3 assumptions regarding the operation (R. D. Luce, 1992). The authors tested these 3 assumptions (i.e., segregation, duplex decomposition, and the additivity of certainty equivalents over joint receipt) using both judged and choice certainty equivalents (CEs). Median choice CEs provided support for both segregation and duplex decomposition but little support for additivity in gains or in losses, whereas median judged CEs also failed to support segregation. The latter failure appears to result from some Ss misunderstanding the instructions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
82.
B Rau C Below W Haensch W Liebrich C von Schilling PM Schlag 《Canadian Metallurgical Quarterly》1995,380(6):359-364
We performed BAEP study to evaluate acoustic nerve involvement in 102 patients affected by peripheral neuropathies of different etiology, predominantly hereditary and inflammatory acquired neuropathies. Prolonged latency of early waves, indicative of slowing in VIII nerve conduction, was found in a high percentage of cases. Abnormalities were far more frequent (44% vs 14%) and severe in patients with demyelinating rather than axonal neuropathy. Among demyelinating neuropathy, the most severe latency delay was found in Hereditary Motor and Sensory Neuropathy type III. The pattern of acoustic nerve involvement differed slightly between Hereditary Motor and Sensory Neuropathy type I and acquired inflammatory demyelinating polyradiculoneuropathy, perhaps reflecting different pathogenetic mechanisms and different sites of VIII nerve demyelination. 相似文献
83.
Formation mechanism of bainitic ferrite and carbide 总被引:6,自引:0,他引:6
Hong-Sheng Fang Jia-Jun Wang Yan-Kang Zheng Ph.D. 《Metallurgical and Materials Transactions A》1994,25(9):2001-2007
Superledges on the broad faces of bainitic ferrite plates have been observed with transmission electron microscope (TEM).
The observed superledges, ranging from less than 1 to 24 nm in height, are imaged in three dimension by way of tilt operation
under TEM. Also, an array of smaller superledges are observed to pile up in front of a secondary phase. Pileup of superledges
in front of a barrier is indicative of the mobility of an individual superledge. The precipitation of carbide associated with
bainitic ferrite is also studied. It is observed that a carbide of a wedgelike shape may exist in front of a superledge with
its tip(i.e., thinner end) penetrating the austenite and its root (the other end) originating at α:γ boundary. This condition indicates
that the observed carbides may nucleate at the austenite side of α:γ phase boundary and grow toward austenite matrix.
This article is based on a presentation made at the Pacific Rim Conference on the “Roles of Shear and Diffusion in the Formation
of Plate-Shaped Transformation Products,” held December 18-22, 1992, in Kona, Hawaii, under the auspices of ASM INTERNATIONAL’S
Phase Transformations Committee. 相似文献
84.
85.
LIU Guangzhen MA Zhanfang SHEN Jianquan 《武汉理工大学学报(材料科学英文版)》2006,21(4):16-18
1 IntroductionGold nanoparticles have attracted considerable atten-tionin manyfields duetotheir some special properties al-though goldis very popularfor beingchemicallyinert[1-3].For example ,gold nanoparticles as amplificationtags havebeenthe subject of research directed at gene analysis[4]and antibody or antigen detection[5-7]due to the large di-electric constant ,ease of preparation,andits biocompati-bility[8].Nanoparticles in the range of 1-10 nmin diameterwould display electronic structur… 相似文献
86.
I. Sevostianov N. K. Sookay C. J. von Klemperer V. E. Verijenko 《Composite Structures》2003,62(3-4):417-421
Attempts to model the degradation of polymer composites have been restricted to modelling the effects of selected degradation mechanisms. No comprehensive model has yet been accepted to predict the effect of the natural environment on the strength of polymer composites. From a review of available literature, it appears that the matrix of a polymer composite is most affected by exposure to the natural environment. Further, the damage appears to progress from the surface into the interior of the laminate. An approach has been developed to determine the properties of the damaged layer and combine the properties of the damaged and undamaged layer to obtain bulk material properties of the laminate. 相似文献
87.
Joseph D. Rigney M.S. Preet M. Singh Ph.D. John J. Lewandowski Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1992,44(8):36-41
A variety of materials have been toughened via the addition of a ductile phase. Brittle silicide intermetallics such as Nb5Si3 have been significantly toughened by niobium particles incorporated during in-situ processing techniques. In the work described here, toughness tests conducted on Nb5Si3 were monitored in a scanning electron microscope to view the process of toughening provided by the niobium particles. In particular, the behavior of the ductile phase was monitored and related to the toughness obtained. In an attempt to vary the behavior of the ductile phase, the composite materials were exposed to a variety of gaseous environments and subsequently tested in air. The resulting toughness, resistance-curve behavior, and in-situ results highlight the importance of the behavior of the ductile phase on subsequent properties. 相似文献
88.
Shiun Ling Ph.D. Michael P. Anderson D.Eng.Sc. 《JOM Journal of the Minerals, Metals and Materials Society》1992,44(9):30-36
The prediction and control of metal grain structures during processing have been major objectives of materials science. However, methodologies that are accurate and can be easily generalized to a variety of processing conditions have been difficult to formulate due to the complexity of the grain interactions. A novel Monte Carlo-based approach that explicitly incorporates these interactions has been developed to simulate the microstructural evolution driven by the minimization of grain boundary energy and lattice defect density. The applicability of this procedure has been demonstrated by the good correspondence between simulation results and experimental observations. This article reviews recent advances in the application of this technique to the investigation of a variety of phenomena, including normal and abnormal grain growth as well as static and dynamic recrystallization. 相似文献
89.
Alton T. Tabereaux Ph.D 《JOM Journal of the Minerals, Metals and Materials Society》1992,44(11):20-26
Refractories for aluminum reduction cell cathodes are changing to meet the needs of new, energy-efficient long-life cathode designs. New refractories and modified versions of old refractories have been introduced, and information on their performance is becoming available. This article reviews some of the advantages and disadvantages of new and old cathode refractory materials. 相似文献
90.
D. M. Kroeger Ph.D. A. Goyal Ph.D. 《JOM Journal of the Minerals, Metals and Materials Society》1992,44(10):42-47
Critical current density (Jc) in the presence of a magnetic field is the property that currently limits many applications of the high-critical-temperature oxide superconductors. Poor current transmission at grain boundaries and weak flux pinning are responsible for the low critical current densities observed in bulk materials. Since 1986, substantial progress has been made both in understanding the microstructural factors affecting Jc and in developing practical fabrication methods. Much of the fundamental understanding has been obtained from studies of YBa2Cu3O7?x while the bismuth and thallium-based compounds appear to offer greater potential as the basis for the first practical conductors. 相似文献