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91.
介绍了瑞士科莱恩(原山德士)公司的一些功能性整理剂如抗紫外线、卫生、拒油和防污等的近况及一些主要产品,并对其应用方法作了评述。  相似文献   
92.
硒作为油脂抗氧化剂的功用探讨   总被引:1,自引:0,他引:1  
何东平 《中国油脂》1995,20(3):53-55
硒作为人体的一种必需微量元素,其生化功能是多方面的。而其中最重要的是硒的抗氧化性,是在七十年代才引起人们的注意,本文就硒在油脂中的抗氧化机理、硒作为油脂抗氧化剂的功用、硒在油脂领域的开发与应用作一探讨。  相似文献   
93.
从杂醇油分离异戊醇生产工艺的探讨   总被引:2,自引:0,他引:2  
为充分利用酒精生产的废料杂醇油,本文通过盐析除水,再进行分馏,得到粗异戊醇。将此粗异戊醇用高锰酸钾处理,然后再进行第二次精馏,得含异戊醇达95×10^-2以上的产品。  相似文献   
94.
Old oil palm trunks that had been felled for replanting were found to contain large quantities of high glucose content sap. Notably, the sap in the inner part of the trunk accounted for more than 80% of the whole trunk weight. The glucose concentration of the sap from the inner part was 85.2 g/L and decreased towards the outer part. Other sugars found in relatively low concentrations were sucrose, fructose, galactose, xylose, and rhamnose. In addition, oil palm sap was found to be rich in various kinds of amino acids, organic acids, minerals and vitamins. Based on these findings, we fermented the sap to produce ethanol using the sake brewing yeast strain, Saccharomyces cerevisiae Kyokai no.7. Ethanol was produced from the sap without the addition of nutrients, at a comparable rate and yield to the reference fermentation on YPD medium with glucose as a carbon source. Likewise, we produced lactic acid, a promising material for bio-plastics, poly-lactate, from the sap using the homolactic acid bacterium Lactobacillus lactis ATCC19435. We confirmed that sugars contained in the sap were readily converted to lactic acid with almost the same efficiency as the reference fermentation on MSR medium with glucose as a substrate. These results indicate that oil palm trunks felled for replanting are a significant resource for the production of fuel ethanol and lactic acid in palm oil-producing countries such as Malaysia and Indonesia.  相似文献   
95.
本文简述了油脂微藻的种类、含油量和脂肪酸成分以及主要用途,介绍了微藻的油脂代谢调控和改良技术研究进展,分析了目前大规模生产中存在的主要问题以及今后发展重点。  相似文献   
96.
Prevailing temperature at anthesis influences pollen health, fertilisation, seed filling, oil and fatty acid accumulation in different circles of sunflower head. Field experiments were conducted, during 2007 and 2008, at Pir Mehr Ali Shah, Arid Agriculture University, Rawalpindi, Pakistan, to document oil and fatty acid distributions in different circles of sunflower head. Hybrid S-278 was planted in randomised complete block design with a two factors factorial experiment, with four replications. At maturity, heads were divided into three equal circles (outer, middle and central); thereafter, oil and fatty acid distributions were separately determined in each circle. Oil and fatty acid concentrations in three circles differed significantly. The outer circle accumulated high oil and oleic contents which decreased to a minimum in the central circle; however, linoleic acid consistently increased, from outer to central circle, during both the years.  相似文献   
97.
杨琦 《中国油脂》1997,22(5):59-60
以油脚为原料,经皂化、盐析、酸化、水洗制成混合脂肪酸。将此混合脂肪酸减压蒸馏,同时用低温水冷却,使芥酸凝聚与其他液体酸分离,从而制得纯度较高的工业品芥酸  相似文献   
98.
The objective of this study was to evaluate the oil extraction process from walnut seeds by pressing followed by extraction with supercritical CO2. In pressing experiments, a factorial arrangement was conducted in order to study the combined effects of seed moisture content (2.5%, 4.5% and 7.5%) and pressing temperature (25, 50 and 70 °C) on oil recovery and quality parameters. For all conditions tested, the oil quality compared well with that of cold-pressed walnut oil. Oil recovery increased significantly as moisture content raised. Highest oil recovery (89.3%) was obtained at 7.5% moisture content and 50 °C temperature. The cake resulting from pressing at these conditions was extracted with CO2 in a high pressure pilot plant with single stage separation and solvent recycle. The effects of two different pressures (200 and 400 bar) and temperatures (50 and 70 °C) with regard to oil yield and quality, and time required for extraction were analyzed. At each condition, the extraction rate changed with the mass of solvent and extraction time. At first, the mass of oil extracted was determined by the oil solubility in CO2 and a linear relationship was observed, where the slope results in the solubility of oil in CO2 at the experiment conditions. After that, the extraction rate was governed by solubility and diffusion, and continuously decreased with time. The colour changed along the extraction from a whitish clear product to a yellow one. Tocopherol and carotenoid contents were significantly higher than those obtained by pressing. Extraction conditions did not affect significantly the fatty acid composition.  相似文献   
99.
The study for the elaboration and certification of four olive oil reference materials covering all the physical–chemical characteristics, defined in Commission Regulation (EC) 1989/2003, is reported herein. The different steps of the process, preparation of reference materials, homogeneity and stability studies, and characterization study have been carried out for 14 laboratories from five European countries. The certificate of analysis for these certified reference materials (CRMs) provide assigned values for concentrations of more than 50 parameters or characteristics of olive oils in compliance with the European legislation about the labeling of food products. The certified values and its corresponding uncertainties were obtained applying robust statistics to the raw data provided by the laboratories taking part in the interlaboratory study. The certificate is valid for a maximum period of 18 months from the elaboration date. These four CRMs are intended for use as a primary material for quality control and for validation of analytical methods for measurements in authentication and adulteration problems of olive oils.  相似文献   
100.
Effects of temperature on the autoxidation and antioxidants changes of soybean, sunflower, and olive oils were studied. The oils were oxidized in the dark at 25, 40, 60, and 80 °C. The oil oxidation was determined by peroxide (POV) and p-anisidine values (PAV). Polyphenols and tocopherols in the oils were also monitored. The oxidation of oils increased with the oxidation time and temperature. Induction period decreased with the oxidation temperature; 87 and 3.6 days at 25 and 60 °C, respectively, for sunflower oil. The activation energies for the autoxidation of soybean, sunflower, and olive oils were 17.6, 19.0, and 12.5 kcal/mol, respectively. Olive oil contained polyphenols at 180.8 ppm, and tocopherols were present at 687, 290, and 104 ppm in soybean, sunflower, and olive oils, respectively. Antioxidants were degraded during the oil autoxidation and the degradation rates increased with the oxidation temperature of oils; for tocopherols, 2.1 × 10−3 and 8.9 × 10−2%/day at 25 and 60 °C, respectively, in soybean oil.  相似文献   
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