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131.
132.
Tullia Gallina Toschi P Capella C Holt W W Christie 《Journal of the science of food and agriculture》1993,61(2):261-266
A rapid procedure has been developed for the isolation of methyl esters of trans-monoenoic fatty acids by silver ion high-performance liquid chromatography. The combined saturated plus trans-monoene fraction was collected for analysis by gas chromatography and comparison with the composition of the unfractionated sample. The trans-monoene contents of partially hydrogenated vegetable oils, determined in this way, are compared with data obtained by Fourier-transform infrared spectroscopy. Alternative methods of base-line correction are discussed. The infrared technique gave values that were a little higher than the chromatographic ones, presumably because the former also detected trans unsaturation in di- and polyunsaturated fatty acids. 相似文献
133.
植物蛋白与乳蛋白在肉制品加工中的应用 总被引:4,自引:1,他引:4
植物蛋白和乳蛋白由于具有较高的营养价值和优良的功能特性,作为食品配料被广泛应用于肉类工业。本文简要介绍了肉制品加工中使用的植物蛋白与乳蛋白、植物蛋白与乳蛋白在肉制品加工中应用的主要功能特性及植物蛋白与乳蛋白在肉制品加工中的作用。 相似文献
134.
本研究用热烫、SO_2、抗坏血酸、蔗糖等抑制方法控制带肉梨汁加工过程中的褐变。颜色指标用罗维朋比色计评价。发现在一小时的加工时间内能完全控制梨汁褐变的最佳条件是:100℃热烫3分钟、抑制剂偏重亚硫酸钠的最小用量为20ppm;或抗坏血酸为250ppm;或糖浆浓度为40%。还对糖浆与SO_2的协同作用及不同pH下SO_2对酶的抑制效果作了研究。 相似文献
135.
136.
Young Seok Oh Eun Seok Jang Jin Young Bock Suk Hoo Yoon Mun Yhung Jung 《Journal of food science》2006,71(4):C260-C268
ABSTRACT: Effects of various fruit and vegetable juices on rubrene oxidation induced by a chemical source of singlet oxygen in a microemulsion system have been studied. The singlet oxygen quenching activities of fruit and vegetable juices were greatly different with different juices. The apple and pear juices exhibited the highest antioxidative activity among the tested juices in singlet oxygen–induced rubrene oxidation, showing 56.69% and 59.34% inhibition, respectively. The grape, kumquat, red cabbage, and spinach juices also showed relatively strong antioxidative activity against singlet oxygen–induced rubrene oxidation. Lemon juice showed the least activity, resulting in 0.63% inhibition of rubrene oxidation. The singlet oxygen quenching activities of 1 mL of apple and pear juices were equivalent to 33.97 and 34.64 mg ascorbate, respectively. Singlet oxygen quenching activities of juices had very low correlation with both ABTS radical scavenging activity ( R 2 = 0.11) and total phenolic contents ( R 2 < 0.1). However, a high correlation ( R 2 = 0.66) was found between the ABTS radical scavenging activities and total phenolic contents of juices. The apple and pear juices also significantly inhibited both erythrocyte lysis and protein oxidation induced by fluorescence light illumination in the presence of methylene blue. Electron spin resonance (ESR) spectroscopy data showed that the protective activities of these juices against biological damages induced by photodynamic ways were, to at least some extent, due to their singlet oxygen quenching abilities. This represents first report on the singlet oxygen quenching activities of the apple and pear juices, and their protective activities against photodynamically induced biological damages. 相似文献
137.
对比研究A、B、C三种果蔬发酵液产品的抗氧化能力和免疫调节能力。采用偶氮二异丁脒盐酸盐(AAPH)诱导的HepG2细胞氧化应激模型评价三种发酵液产品对细胞内活性氧簇(ROS)的影响,应用刀豆蛋白A(ConA)和脂多糖(LPS)诱导小鼠T/B淋巴细胞,检测其增殖能力,应用LPS诱导小鼠腹腔巨噬细胞,检测其吞噬能力和NO释放量。结果表明:三种果蔬发酵液具有较强的降低细胞内ROS含量的能力,果蔬发酵液A可使胞内ROS含量降低至55%;三种果蔬发酵液可提高淋巴细胞的增殖能力和腹腔巨噬细胞的吞噬能力,促进NO释放,在稀释倍数为104时果蔬发酵液A处理组NO释放量最高(4.06μmol/L)。三种果蔬发酵液具有较好的抗氧化活性和增强免疫的功能。 相似文献
138.
Ultra‐high‐pressure homogenization (UHPH) system for producing high‐quality vegetable‐based beverages: physicochemical,microbiological, nutritional and toxicological characteristics 下载免费PDF全文
139.
以环氧氯丙烷、三甲胺、硫酸为原料合成纤维素纤维改性剂AM,研究了反应物量比,反应溶液的pH值及反应温度对产物合成转化率的影响,并得出了合成产物的优化工艺;采用改性剂AM对纤维素纤维织物进行改性,探讨了改性织物对天然植物染料的染色性能.结果表明,纤维素纤维改性织物的植物染料染色性能有明显提高. 相似文献
140.
Gretel BESCOBY 《粮油食品科技》2022,30(1):50-57
Increasing volumes of oils and fats are produced annually with a large section that are traded internationally. The International Organization for Standardization(ISO) body develops international standards covering almost all aspects of technology and manufacturing with 23,882 standards currently published. Standards in the animal and vegetable fats and oils sector is developed by Technical Committee ISO/TC 34, Food products, Subcommittee SC 11, Animal and vegetable fats and oils. Standards are developed through consensus by national members that represent ISO in their country. Each Standard is developed within a determined timeframe and goes through various pre-determined stages such as project proposal, development, national voting and commenting on the draft Standard to final publication. ISO TC34/SC11 Standards range from sampling of oils and fats, sample preparation to analysis of its composition, the minor components, and quality and identity parameters as well as contaminants. The analysis results are used by industry for product development, labelling, research and to provide peace of mind for consumers on its safety. An important future trend is the focus on the safety concerns from either environmental contamination(e.g. mineral oils) or processing contaminants such as esters of 3-MCPDs(3-monochloropropane-1,2-diol or 3-chloropropane-1,2-diol). 相似文献