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1.
Yajing Qi Yuying Yang Alkassoumi Hassane Hamadou Qiuyun Shen Bin Xu 《International Journal of Food Science & Technology》2022,57(4):2104-2112
Wheat bran is rich in functional ingredients, but the high level of lipase limits its applications. Tempering–preservation treatment (at 70–90 °C with moisture of 20%–40% for 1–4 h) was exploited for stabilising wheat bran and its effect on polyphenols was investigated. The results showed that more lipase was inactivated at higher tempering moisture, temperature and longer time. The optimum condition for inactivation of wheat bran lipase was 30% moisture and 90 °C for 4 h. The inactivation rate reached 93.8% with a residual enzyme activity of 0.264 U g−1. Under the optimum condition, the sum of free phenolic acids rose from 25.4 to 55.8 µg g−1. As for bound phenolic acids, there was a slight increase of hydroxybenzoic acid derivatives but a slight decrease of hydroxycinnamic acid derivatives. The total contents of phenolic acids before and after stabilisation were not significantly different. This study showed the possibility of using tempering–preservation as an efficient method for inactivation of wheat bran lipase while maintaining its phenolic compounds, which could be used in the production of whole wheat flour. 相似文献
2.
Bin Zhang Xuesong Jiang Fei Shen Xueming He Yong Fang Qiuhui Hu 《International Journal of Food Science & Technology》2021,56(6):2588-2595
This work intends to develop an online experimental system for screening of deoxynivalenol (DON) contamination in whole wheat meals by visible/near-infrared (Vis/NIR) spectroscopy and computer vision coupling technology. Spectral and image information of samples with various DON levels was collected at speed of 0.15 m s−1 on a conveyor belt. The two-type data were then integrated and subjected to chemometric analysis. Discriminant analysis showed that samples could be classified by setting 1000 μg kg−1 as the cut-off value. The best correct classified rate obtained in prediction was 93.55% based on fusion of spectral and image features, with reduced prediction uncertainty as compared to single feature. However, quantification of DON by quantitative analysis was not successful due to poor model performance. These results indicate that, although not accurate enough to provide conclusive result, this coupling technology could be adopted for rapid screening of DON contamination in cereals and feeds during processing. 相似文献
3.
文章简要介绍了化学除臭清洗剂JX-518的组成,并对采用该清洗剂对污水汽提系统进行化学除臭清洗的清洗过程及注意事项进行了详细介绍。实践证明,清洗后系统残液中硫化物及氨氮可降至很低,取得了很好的清洗效果。 相似文献
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五.牛奶厂的清洗。目前,牛奶厂采用的清洗方式主要是CIP清洗(Cleaning in place),原地清洗或称定置清洗,即在基本不拆卸或挪动机械装置和管线的情况下对生产过程中能与牛奶发生接触的设备表面进行的清洗。其冲刷、清洗、灭菌的整个过程全部实现了自动化因此大大降低了劳动强度。而有一些不 相似文献
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在介绍“铝丝印”概念的基础上,从金属腐蚀学的观点出发,分析了“铝丝印”形成的电化学腐蚀机理,并提出了具体的解决措施。 相似文献
9.
Larissa Canilha Walter Carvalho Marco Giulietti Maria Das Graças Almeida Felipe João Batista Almeida E Silva 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2008,83(5):715-721
BACKGROUND: Xylitol bioproduction from lignocellulosic residues comprises hydrolysis of the hemicellulose, detoxification of the hydrolysate, bioconversion of the xylose, and recovery of xylitol from the fermented hydrolysate. There are relatively few reports on xylitol recovery from fermented media. In the present study, ion‐exchange resins were used to clarify a fermented wheat straw hemicellulosic hydrolysate, which was then vacuum‐concentrated and submitted to cooling in the presence of ethanol for xylitol crystallization. RESULTS: Sequential adsorption into two anion‐exchange resins (A‐860S and A‐500PS) promoted considerable reductions in the content of soluble by‐products (up to 97.5%) and in medium coloration (99.5%). Vacuum concentration led to a dark‐colored viscous solution that inhibited xylitol crystallization. This inhibition could be overcome by mixing the concentrated medium with a commercial xylitol solution. Such a strategy led to xylitol crystals with up to 95.9% purity. The crystallization yield (43.5%) was close to that observed when using commercial xylitol solution (51.4%). CONCLUSION: The experimental data demonstrate the feasibility of using ion‐exchange resins followed by cooling in the presence of ethanol as a strategy to promote the fast recovery and purification of xylitol from hemicellulose‐derived fermentation media. Copyright © 2008 Society of Chemical Industry 相似文献
10.
Miriam A Martinello Mauro Villegas Maria del C Pramparo 《Journal of the science of food and agriculture》2007,87(8):1559-1563
A process of physical refining wheat germ oil using the technique of molecular distillation (MD) is presented in this work. Wheat germ oil was obtained from the germ by solvent extraction using hexane and also by cold pressing. The oil extracted with hexane was degummed and bleached before deacidification in order to modify the parameters of phosphorus and color. The goal in carrying out the stage of physical refining by MD was to preserve the maximum amount of original antioxidative potential obtained from extraction of the crude oil. The effect of evaporation temperature of one‐stage MD on the efficiency of free fatty acid elimination was studied. The antioxidant portion was followed by means of analytic determination of tocopherols by high‐performance liquid chromatography. Tocopherol retention up to 98% was achieved in the oil extracted by pressing, and yields of up to 96% were achieved in the oil extracted with hexane. Copyright © 2007 Society of Chemical Industry 相似文献