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131.
对盐浴螺旋盘管式结构的焦炉上升管高温荒煤气余热回收装置进行了以烟气代替荒煤气的传热性能模拟试验,得到了上升管余热回收装置螺旋盘管环形套筒的外壁温度分布、上升管内烟气侧的传热系数、环形套筒内螺旋盘管外盐浴的自然对流传热系数等试验研究结果。结果表明,装置螺旋盘管环形套筒的外壁温度分布并非均匀,随上升管内烟气温度的升高而波动增大;烟气侧对流传热系数在Re数高于2900后随Re数的增大而明显上升;螺旋盘管外盐浴的自然对流传热系数随熔盐温度的升高几乎不变。根据试验结果拟合出环形套筒内螺旋盘管外盐浴的自然对流传热关联式,为实际的工程应用提供参考。 相似文献
132.
Chien‐Hao Chen Ming‐Hsu Chang Ming‐Kwei Shih Chii‐Ming Jiang Ming‐Chang Wu 《Journal of the science of food and agriculture》2009,89(15):2551-2557
BACKGROUND: The major defect of the interspecific variety Golden Muscat (Vitis vinifera × Vitis labrusca) is the inheritance of the specific foxy off‐flavours from the parent species Vitis labrusca. Thermal treatment is a traditional method of producing fortified wine that originated from the subtropical Portuguese island of Madeira. This technique was used to treat Golden Muscat fortified wine in order to investigate the effects of thermal treatment on the physicochemical composition and sensory qualities of the wine. RESULTS: The control wine had the lowest total phenol concentration, total flavonol concentration and total acidity. Increased colour intensity in all thermal‐treated samples was detected. The amount of foxy methyl anthranilate in the wine decreased significantly (P < 0.05) after thermal treatment. Panellists indicated that, compared to the control wine, the thermal‐treated wines had higher flavour complexity, flavour intensity, persistence and balance. The control wine exhibited an unpleasant foxy flavour. CONCLUSION: These results suggest that the thermal treatment technique can be used for the production of Golden Muscat fortified wines with desirable flavour. This technique could assist local winemakers to produce an interspecific variety Golden Muscat fortified wine of acceptable quality. Copyright © 2009 Society of Chemical Industry 相似文献
133.
醋酸发酵结束后,醋醅或醋醪经后熟陈酿,可改进食醋的口感、风味.在液态发酵醋醪中利用曲霉酶系反应,可在短时间内增加液态发酵醋的色泽、氨基酸类、糖类、不挥发酸等物质的含量,使口感柔和、增加风味.其特点是:充分发挥曲霉酶系的作用,利用制剂中增加的有效成分,在醋醪中分解与合成,弥补了其风味的不足,从而达到增加和改善液态发酵食醋的目的.方法简便、成本低,是弥补液态发酵食醋风味不足的好办法. 相似文献
134.
牛骨酶解产物中咸味肽组分的分离纯化及成分研究 总被引:2,自引:0,他引:2
采用Sephadex G-15和G-50凝胶色谱柱分离牛骨酶解产物,结合感官分析,得到Sephadex G-15的峰Ⅱ和G-50的峰Ⅲ两个咸味组分;用反向高效液相色谱和基质辅助激光解析电离-飞行时间质谱仪分析咸味组分:Sephadex G-15得到的咸味组分中主要有两种成分,相对分子质量在800~1000之间;Sephadex G-50得到的咸味组分中主要有3种组分,相对分子质量在800~2000之间。两种咸味肽组分的极性较强,且均有相对分子质量为849.38的多肽。 相似文献
135.
Modification of pomological characteristics and flavour components of fruits and virgin olive oil following wastewater irrigation and soil tillage
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136.
The use of atmospheric and room temperature plasma mutagenesis to create a brewing yeast with reduced acetaldehyde production
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Chunfeng Liu Qi Li Chengtuo Niu Yaping Tian Yijin Zhao Xiangsheng Yin 《Journal of the Institute of Brewing》2018,124(3):236-243
High acetaldehyde levels in beer from yeast metabolism is a major concern for brewers in China. To obtain a strain with lower acetaldehyde production, this work reports a novel approach based on atmospheric and room temperature plasma mutagenesis and high‐throughput screening using 4‐methylpyrazole + disulphiram plating. A mutant LAL‐8a with lower acetaldehyde‐producing capability was obtained. The alcohol dehydrogenase activity decreased by 54% compared with the wild‐type M14 and the aldehyde dehydrogenase activity increased by 64% of the wild‐type strain. Through domestication and fermentation in EBC tubes, the mutant LAL‐8a was shown to produce 2.2 mg/L acetaldehyde, 88.2% less than the wild‐type strain M14. In addition, the ratio of higher esters to alcohols in beer fermented by the mutant LAL‐8a (0.28) was higher than M14 (0.16). The fermentation performance of LAL‐8a was similar to that of the wild‐type M14. This work suggests strain LAL‐8a a promising option for the brewing industry. © 2018 The Institute of Brewing & Distilling 相似文献
137.
《Journal of the Institute of Brewing》2017,123(1):66-69
Standard brewing yeast cannot utilize larger oligomers or dextrins, which represent about 25% of wort sugars. A brewing yeast strain that could ferment these additional sugars to ethanol would be useful for producing low‐carbohydrate diabetic or low‐calorie beers. In this study, a brewing yeast strain that secretes glucoamylase was constructed by mating. The resulting Saccharomyces cerevisiae 278/113371 yeast was MAT a/α diploid, but expressed the glucoamylase gene STA1 . At the early phase of the fermentation test in malt extract medium, the fermentation rate of the diploid STA1 strain was slower than those of both the parent strain S. cerevisiae MAFF113371 and the reference strain bottom‐fermenting yeast Weihenstephan 34/70. At the later phase of the fermentation test, however, the fermentation rate of the STA1 yeast strain was faster than those of the other strains. The concentration of ethanol in the culture supernatant of the STA1 yeast strain after the fermentation test was higher than those of the others. The concentration of all maltooligosaccharides in the culture supernatant of the STA1 yeast strain after the fermentation test was lower than those of the parent and reference strains, whereas the concentrations of flavour compounds in the culture supernatant were higher. These effects are due to the glucoamylase secreted by the constructed STA1 yeast strain. In summary, a glucoamylase‐secreting diploid yeast has been constructed by mating that will be useful for producing novel types of beer owing to its different fermentation pattern and concentrations of ethanol and flavour compounds. Copyright © 2017 The Institute of Brewing & Distilling 相似文献
138.
《Journal of the Institute of Brewing》2017,123(1):5-12
Chinese Baijiu (Chinese spirit or Chinese liquor) is one of the six major distilled spirits in the world, and is renowned overseas. Chinese Baijiu has a long history of more than 1000 years when people first begin to brew liquor using distillation. So far, Chinese Baijius have formed 12 types according to their flavour characteristics. The strong flavour Chinese spirit is regarded as one of the typical representatives, and occupies a > 70% market share in China. The liquor brewing process is under an open environment, with grains as the fermentation substrates, as well as Daqu as the saccharifying ferment. The brewing process is complex and impacted by multiple factors. Among the factors, the microorganisms have important influences on the brewing process and product quality of liquors. In the past decades, a series of research achievements have been made with strong flavour Chinese spirits. However, reviews related to this field are relatively few. In this paper, we have reviewed strong flavour Chinese spirits including the introduction, brewing process, microorganism diversity of Daqus , fermented grains and pit muds, and the application of microbes. Copyright © 2017 The Institute of Brewing & Distilling 相似文献
139.
140.
介绍了钻井水溶法开采几种钻井连通工艺的特点,特别是定向压裂连通技术工艺特点、施工方法以及在盐类矿物开采中的应用实例. 相似文献