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11.
本文阐述循环经济的理念在茶业生产中的应用。资源节约利用,产业持续发展和环境保护是区别传统茶业生产与循环农业模式的主要因素。金华市婺城区良好的气候条件、良种茶园的建设成果、茶叶生产加工机械化的普及改良和茶业标准化、组织化建设为发展茶业循环经济创造了有利的条件,但传统茶业生产根源的广泛性和循环经济意识的缺乏、及相应的支撑体系不完善也制约了茶业循环经济的发展。加大宣传,提高循环经济意识,加强循环茶业技术支撑和成熟模式的示范推广,完善保障体系,是推动茶业循环经济发展的重要途径。 相似文献
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Alessandro C. Martins Lais BukmanAlexandro M.M. Vargas Érica O. BarizãoJuliana C.G. Moraes Jesuí V. VisentainerVitor C. Almeida 《Food chemistry》2013
This study proposes a FRAP assay adapted to FIA system with a merging zones configuration. The FIA system conditions were optimised with the response surface methodology using the central composite rotatable design. The optimisation parameters studied were: the carrier flow rate, the lengths of the sample and reagent loops, and reactor length. The conditions selected in accordance with the results were: carrier flow rate of 1.00 ml/min, length of the loops 18.2 cm and length of the reaction coil 210.1 cm. The detection and quantification limits were, respectively, 28.6 and 86.8 μmol/l Fe2+, and the precision was 1.27%. The proposed method had an analytical frequency of 30 samples/h and about 95% less volume of FRAP reagent was consumed. The FRAP assay adapted to the FIA system under the optimised conditions was utilised to determine the antioxidant activity of tea samples. 相似文献
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Effect of tannase enzymatic treatment on protein-tannin aggregation and sensory attributes of green tea infusion was investigated. Green tea leaves were extracted with hot water at 85 °C for 20 min, the tea infusion was then treated with tannase. Results showed that both EGCG and ECG of the tea catechins were hydrolyzed by tannase into EGC and EC, respectively, accompanied by production of gallic acid. The tannase-treated tea infusion had a relatively lower binding ability with protein. Changes in the content of tea catechins, formation of tea cream, and turbidity of tea infusion with or without tannase treatment were measured after 4 weeks. Content of catechins in the tannase-modified tea remained almost unchanged, while those without tannase treated (control) decreased significantly (p < 0.05). Meanwhile, better color appearance and less tea cream formation were observed for the tannase-treated green tea, and tea cream formed for the control after storage. Results of the sensory evaluation showed that mouth feeling, taste and the overall acceptance of the tannase-treated green tea infusion were all better than those of the control. 相似文献
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Extraction of caffeine from tea stalk and fiber wastes using supercritical carbon dioxide 总被引:3,自引:0,他引:3
The purpose of this study was to investigate obtaining of caffeine from tea plant wastes by supercritical carbon dioxide extraction. Experiments were carried out with tea stalk and fiber wastes of Turkish tea plants that has no economical value. Stalk and fiber wastes were supplied from tea factories. These wastes were ground, sieved and dried at 105 °C temperature in an oven. Parameters affecting caffeine leaching from tea wastes were determined to be, extraction time, extraction temperature, carbon dioxide flow rate, process pressure and particle size. The maximum yield of caffeine from tea stalk wastes and fiber wastes were 14.9 mg/g tea stalk and 19.2 mg/g tea fiber, respectively. The yield increase had been recorded as 61.9% and 65.5%, respectively, in comparison with the chloroform extraction of tea stalk and fiber wastes. 相似文献
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原子荧光法在茶叶砷含量测定上的应用 总被引:2,自引:0,他引:2
用氢化物发生-原子荧光光谱法测定茶叶砷含量,方法简单、精密度好、准确度高、线性范围宽,仪器价格例宜,值得在茶叶行业加以推广使用。 相似文献
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Mehlich 3(M3)浸提剂是一种适合于不同类型土壤、能浸提不同有效态元素的通用浸提剂,而茶园土壤是一类较特殊的酸性土壤,它的强酸性、富铁铝等特性,是否适用M3浸提方式,国内鲜有报导。本文通过对目前较普遍适用茶园土壤的浸提方法与M3浸提剂相比较,结果表明M3浸提茶园土壤各元素有效态含量要高于常用浸提方法,K、Ca、Mg、Cu、Zn、Mn、Cr等元素含量结果相差不大,但Fe含量相差3倍,B、Cd等元素含量结果相差7~8倍,且各元素有效态含量呈极显著正相关。对M3方法及电感耦合等离子体光谱仪(ICP)精密度测定后认为M3方法结合ICP测定精密度高,结果稳定可靠。 相似文献
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膜浓缩技术与真空冷冻干燥在茶饮料中的应用 总被引:10,自引:0,他引:10
膜浓缩与真空冷冻干燥应用于茶饮料工业中,与传统工艺方法比较,解决了茶饮料中冷后浑,混浊等缺陷。 相似文献