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71.
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Monodisperse FePt nanoparticles with size of 4.5 and 6.0 nm were prepared by simultaneous reduction of platinum acetylacetonate
and thermal decomposition of iron pentacarbonyl in benzylether. The crystallography structure, size, and composition of the
FePt nanoparticles were examined by X-ray diffraction and transmission electron microscopy. Energy dispersive X-ray spectrometry
measurements of individual particles indicate a broad compositional distribution in both the 4.5 and 6 nm FePt nanoparticles.
The effects of compositional distribution on the phase-transition and magnetic properties of the FePt nanoparticles were investigated. 相似文献
73.
John Brewer 《集成电路应用》2010,(3):34-35,37
2010年802.11n家庭无线视频传输市场终于起飞,幕后的基于硅技术的大功率WLAN PA功不可没,它解决了无线视频传输中如何在峰值RF功率下保持PA性能的关键技术难题。 相似文献
74.
Sarah E. Wicklund Candace Homco-Ryan Kevin J. Ryan Floyd K. Mckeith Brian J. Mcfarlane M. Susan Brewer 《Journal of food science》2005,70(3):S242-S248
ABSTRACT: Strip loins were removed 48 h postmortem from beef sides ( n = 20 pairs) to assess the effects of enhancement before or after aging on quality attributes of beef strip steaks. Strip loins were enhanced to 108% of original weight to contain 0.4% alkaline phosphate, 0.3% salt, 0.1% natural flavoring (on a final weight basis), and added water for comparison with non-enhanced samples. Regardless of when enhancement occurred relative to aging, enhanced samples were more tender, juicy, and salty than their non-enhanced counterparts. Enhanced samples were lighter, less red and less yellow, and had lower L *, a *, and b * values than non-enhanced samples; however, they generally had lower hue angles indicating that their color was closer to the true red axis of the color scale. Samples enhanced before aging achieved maximum tenderness after 14 d, whereas those enhanced after aging experienced no tenderness changes. Warner- Bratzler shear values were lower and pH values were higher in enhanced steaks than in controls. 相似文献
75.
Cooking rate, pH and final endpoint temperature effects on color and cook loss of a lean ground beef model system 总被引:4,自引:0,他引:4
To assess the effects of pH, heating rate and endpoint temperature on instrumental and visual color of ground beef, pH was adjusted to 5.2–6.4, samples were heated at 0.7°C or 3°C/min to 55, 60, 65, 70, 75 or 80°C in a water bath. Cooking rate had no effect on cook loss, instrumental or visual color. Regression equations for linear, quadratic and/or cubic effects of pH and/or endpoint temperature were significant for most color indices. Amount of variance explained by the model and R2 was increased by adding the calculated percentages of metmyoglobin and/or deoxymyoglobin to the regression models. The predicted sensory brownness score (0=very pink, 7.5=intermediate pink/brown, 15=intense brown) for samples with pH 5.75 cooked to 70°C was 9.75. Samples with a pH of 5.5 achieved this brownness score at 67°C. Samples with a pH of 5.2 achieved this brownness at 58°C. 相似文献
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William Roshan Quadros Ved Vyas Mike Brewer Steven James Owen Kenji Shimada 《Engineering with Computers》2010,26(3):231-247
This paper proposes a framework for generating mesh sizing functions for assembly models. Size control is crucial in obtaining
a high-quality mesh with a reduced number of elements. The reduction in the number of elements will decrease computation time
and memory use during mesh generation and analysis. The framework consists of a background octree lattice for storing the
sizing function, a set of source entities for providing sizing information based on geometric information, and an interpolation
module for calculating the sizing on the background octree lattice using the source entities. Source entities are generated
by performing a detailed systematic study to identify all the geometric factors of an assembly. Disconnected skeletons are
extracted and used as tools to measure 3D proximity and 2D proximity, which are two of the geometric factors. The framework
facilitates the generation of a variety of meshes with a low computational cost, to meet industry needs. The framework has
been tested on many industrial parts, and sizing control on a few typical assemblies has been presented to demonstrate the
effectiveness of the proposed framework. 相似文献
80.
HB Huang YQ Song M Hsei R Zahorchak J Chiu C Teuscher EJ Smith 《Canadian Metallurgical Quarterly》1999,90(1):240-242
The development and partial characterization of turkey genomic libraries enriched for TG, GAT, and CCT simple sequence repeats (SSR) are described. The primary library, established using conventional methods, was enriched for each of the three SSR by single-primer polymerase chain reaction (PCR). The three enriched libraries were screened by standard hybridization and washing protocols under moderate to high stringency conditions. The utility of a fraction of the markers was evaluated based on the polymorphism of PCR-amplified products in a backcross reference DNA panel. The panel consisted of genomic DNA samples from three backcrossed families developed from a cross of a wild male turkey to three inbred Orlopp line C females. A total of 181 sequences from positive clones have been characterized and deposited in GenBank. About 60% of the 60 primer pairs designed from SSR-containing sequences detected polymorphism in the reference DNA panel. The turkey genomic DNA reference panel, the enriched libraries, and the markers described here provide an opportunity to begin to characterize the turkey genome and to develop a useful public genetic map for this economically important species. 相似文献