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61.
董酒有三独特,即生产工艺独特,微量成分量比关系独特,风格独特。其香型特征在全国白酒中独树一帜,具有舒适优雅的药香;酯类含量较平衡,表现出复合酯香。丁酸乙酯与己酸乙酯之比高于其他名白酒数倍,乳酸乙酯约为其他名白酒的1/2~1/3;高级醇中正丙醇比其他名白酒高1倍至数倍,仲丁醇高出5~10倍;醇酯比>1,在1∶0.8~1.0,其他名白酒为1∶3以上;酸酯比>1,在1∶0.6~0.8,其他名白酒为1∶2以上。董酒是同类香型白酒的典型代表,应确立为“董型”。(一平 相似文献
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D. Donald Muir Simon A.R. Williams Adnan Y. Tamime & M. E. Shenana 《International Journal of Food Science & Technology》1997,32(4):279-287
The sensory character of 16 samples of commercial, processed cheese spread has been characterized. Samples were selected to provide information on variations both between brands and, for products differing in fat content, within brands. Products were rated for eight flavour attributes and six textural attributes by a panel of 13 professional assessors. Significant differences in both the flavour and the texture of the spreads were associated with brand. No systematic differences were found between the flavour attributes and the fat content of the spread. However, differences were revealed between spreads – classified on the basis of fat content as regular, light and ultra light – in the sensory dimensions associated with texture and mouth feel. Nevertheless, within some brands the effect of reducing fat content was minimal. This result was probably achieved by other changes in product formulation. 相似文献
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In this work, a simple and fast method for the determination of diacetyl by gas-chromatographic technique coupled with flame ionisation detector (GLC-FID) was developed. Diacetyl is the typical butter flavour, but it is also commonly present in others fermented dairy products. Recently, diacetyl determination has also attracted interest because it is one of the parameters on which lactic acid bacteria (L.A.B.) are characterized and valued. Only acetone and 2,3-pentanedione were used as chemicals. After centrifugation of acetone–milk mixture, supernatant was filtered and directly injected into gas-chromatographic apparatus, without a further purification procedure step.
This method was accurate and precise; diacetyl recovery on milk was 97% and the detection limit was 1 mg L−1. Finally, by using this method, diacetyl was easily determined in fresh and high-temperature treated milk, commercial butter, yoghurt and also in a series of L.A.B. performance tests. 相似文献
67.
Recent observations on the occurrence of fishy flavour in bacon 总被引:1,自引:0,他引:1
David T. Coxon Kenneth E. Peers Nerys M. Griffiths 《Journal of the science of food and agriculture》1986,37(9):867-872
An examination of reject bacon samples supplied directly from a factory showed that some samples described by a sensory panel as oily and fishy contained significantly higher levels of long chain polyunsaturated fatty acids (PUFA) in their fat than normal samples. When bacon samples obtained from retail outlets were similarly analysed and then subjected to sensory assessment, those found to contain long chain PUFA were given significantly higher scores for oily and fishy flavour. Observations on the fatty acid composition of fishy bacon samples as compared to non-fishy ones and further investigation into the diets of pigs producing suspect carcasses led to the conclusion that too high a content of fish products in the diet was the main cause of the problem. Contrary to what had been believed, fresh non-fishy bacon samples did not develop fishy flavour after storage at ?20°C for 15 weeks. Perceived fishiness was not related to total copper content as determined by atomic absorption spectroscopy. 相似文献
68.
K. Erdal 《Journal of the Institute of Brewing》1986,92(3):220-224
Colloidal haze in beer is due to the precipitation of proteins by proanthocyanidins. Carlsberg Research Center reported in 1977 that the use of barley mutants which block the biosynthesis of catechins and proanthocyanidins in the grain prevents the formation of haze in beer. The results from ten years of malting and brewing research with proanthocyanidin-free barley and malt are reviewed. 相似文献
69.
J.H. SWIEGERS P.J. CHAMBERS I.S. PRETORIUS 《Australian Journal of Grape and Wine Research》2005,11(2):109-113
Drinking wine is a manifestly sensuous experience. Wine stimulates most of our senses; particularly smell (olfaction) and taste, and, to a lesser extent, sight and touch. These sensory inputs interact with the limbic system in our brain which is associated with emotions and memory. Agreeable smells can thus evoke feelings of enjoyment and nostalgia. But how are tastants and aromas detected? Over the past few years a great deal has been learnt about how small tastant and odorant molecules are detected by specific protein receptors located in our mouth and in nasal cavities, respectively. Indeed, we have a vast array of olfactory receptors encoded by a group of genes that represent a significant part of the human genome. Interestingly, many more aroma compounds can be detected and discriminated than can be accounted for by the number of olfactory receptors that are encoded by our genes. Such disparity implies a level of complexity in this system which is not yet fully understood. Sophistication in olfaction is something that winemakers (and drinkers!) have long appreciated, and now scientists are beginning to unravel some of the underlying mysteries. Discovering why some individuals are more receptive to different tastes and smells than others will help wine producers understand variation in consumer preferences between different parts of the world, and possibly capture new opportunities in a changing global marketplace. Given such prospects, this present review offers a timely summary of some key developments in our understanding of odorant and tastant detection. We also consider how genetic components in human olfaction might be utilised to develop a ‘biosensor’ for aroma detection and discrimination. 相似文献
70.
Determining wine aroma from compositional data 总被引:1,自引:0,他引:1