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1.
The effect of fermentation on the fatty acids (FA) content and composition of cassava tuber meal has been investigated. The major FA of the cassava tuber meal (CTM) lipid were oleic and palmitic acids. Other FA found in decreasing order were linoleic, linolenic, palmitoleic, stearic, myristic, pentadecanoic, heptadecanoic and nonadecanoic acids. Fermentation of the CTM resulted in substantial increases in the absolute quantities of the individual FA detected except linolenic acid. However fermentation did not alter the pattern of composition of the FA, but it caused increases in the composition of saturated FA and decreases in certain unsaturated ones. Stearic acid increased in composition by about 92.6% and pentadecanoic by about 50%. A reduction of about 72% of the linolenic acid and 24.2% of the palmitoleic acid composition were obtained in the fermented CTM lipid.  相似文献   
2.
A study of the prevalences of Salmonella, Listeria and thermophilic campylobacters in a dedicated commercial poultry feed mill was undertaken. Salmonella was frequently recovered in samples taken in the preheat and postheat treatment areas of the mill with the overall percentage of samples positive found to be 18.8% and 22.6%, respectively. Feed ingredients and dust collected in the preheat treatment locations within the mill were frequently contaminated with Salmonella (11.8% and 33.3% of samples, respectively). High prevalences of Salmonella were also detected in dust samples (24.2%) obtained from the postheat treatment area of the mill and from feed delivery vehicles (57.1%).
Listeria was also recovered from samples at pre- and postheat treatment areas within the mill with overall isolation rates of 14.1% and 18.5% observed, respectively. The most frequently observed species of Listeria recovered from samples in both areas within the mill was L. innocua, L. monocytogenes, L. grayi and L. welshimeri.
No thermophilic campylobacters were recovered from any of the samples analyzed in the current study.  相似文献   
3.
SUMMARY— The nutritive value of infant foods (prepared from buffalo milk) containing 10%, 12.5% and 15% protein and fortified with DL-methionine has been studied in experiments with albino rats. The mean weekly growth rate of rats receiving milk food II (10% protein and 20% fat) and fortified with DL-methionine was of the same order as those obtained with milk foods containing 12.5%, 15%, 22% and 26% protein. Milk food II containing 10% protein (not fortified with DL-methionine) promoted significantly less growth than the same food fortified with DL-methionine and other milk foods containing 12.5% to 28% protein.
The protein efficiency ratio of the milk food fortified with DL-methionine (4.0) was significantly higher than that (3.3) of the unfortified milk food at 10% level of protein in the diet. The results indicate that humanized milk food from buffalo milk containing about 12.0% protein and 20% fat and fortified with DL-methionine will be suitable for feeding infants in place of full cream milk powder in developing countries where milk is in short supply. Adoption of the above formula for infant milk food manufactured in the country will help to double the output of infant food from the same quantity of buffalo milk without appreciable increase in cost.  相似文献   
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Realizing the real-time detection of CH4 is important for the safety of human life. A facile hydrothermal method was used to synthesize Ag nanoparticles-decorated ZnO porous nanoflakes (PNFs) in this study. The characterization results confirmed that Ag nanoparticles had been decorated in ZnO nanoflakes with the thickness of ~10 nm. The gas-sensing properties of Ag-decorated ZnO nanoflakes were also investigated. While the gas-sensing performances of ZnO were remarkably improved by decorating Ag nanoparticles on the surface of ZnO nanoflakes, the response of the Ag-decorated ZnO sensor to 3000 ppm CH4 is almost 1.3 times as high as that of pristine ZnO sensor. The obtained Ag/ZnO sensor exhibits better long-term stability and shorter response recovery time (5/38 s) in the comparison with pristine ZnO, demonstrating the possibility for the actual detection of CH4. The enhanced CH4 sensing performance can be attributed to the synergism between the unique hierarchical porous structure and the sensitizing actions utilized by the Ag nanoparticles.  相似文献   
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This letter describes a technique to evaluate the radiometric quality of distributed target responses extracted from Synthetic Aperture Radar (SAR) data. The approach is original in that it aims to estimate the Equivalent Number of Looks of clustered pixels, a parameter which summarizes the first order statistics of speckle. This empirical method can be applied to processed, interpolated, and even speckle-filtered, SAR images. Using ERS-1 Precision Image SAR data, it is shown, first, how to discriminate between uniform and non-uniform targets, and, then, to estimate the radiometric resolution of pixels gathered according to several clustering schemes.  相似文献   
8.
Lithium‐ion battery performance is intrinsically linked to electrode microstructure. Quantitative measurement of key structural parameters of lithium‐ion battery electrode microstructures will enable optimization as well as motivate systematic numerical studies for the improvement of battery performance. With the rapid development of 3‐D imaging techniques, quantitative assessment of 3‐D microstructures from 2‐D image sections by stereological methods appears outmoded; however, in spite of the proliferation of tomographic imaging techniques, it remains significantly easier to obtain two‐dimensional (2‐D) data sets. In this study, stereological prediction and three‐dimensional (3‐D) analysis techniques for quantitative assessment of key geometric parameters for characterizing battery electrode microstructures are examined and compared. Lithium‐ion battery electrodes were imaged using synchrotron‐based X‐ray tomographic microscopy. For each electrode sample investigated, stereological analysis was performed on reconstructed 2‐D image sections generated from tomographic imaging, whereas direct 3‐D analysis was performed on reconstructed image volumes. The analysis showed that geometric parameter estimation using 2‐D image sections is bound to be associated with ambiguity and that volume‐based 3‐D characterization of nonconvex, irregular and interconnected particles can be used to more accurately quantify spatially‐dependent parameters, such as tortuosity and pore‐phase connectivity.  相似文献   
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Abstract

Analysis of Landsat Thematic Mapper (TM) image of 14 May 1984 has shown that such data can be used to survey vegetation and sediment distributions in the intertidal zone of the Wash estuary at a spatial detail comparable with current methods practised by the.Nature Conservancy Council. Multispectral classification of this TM image showed good separation of salt-marsh vegetation communities which had recently been surveyed by the Nature Conservancy Council and for which reliable training data could be taken. The sensitivity of classification performance, using both parametric and non-parametric algorithms, to apparently minor differences in phenology at training site locations demonstrates two requirements for improved salt-marsh classification. They are the need for strict definition of training data and that TM wave bands 2, 3, 4 and 5 provide suitable spectral vectors for classifying intertidal environments.  相似文献   
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