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991.
Jun-Ru Qi Xiao-Quan Yang & Jin-Song Liao 《International Journal of Food Science & Technology》2009,44(11):2296-2302
The functional acid-precipitated soy protein (SAPP)–dextran conjugate was prepared by dry-heated storage at 60 °C under 79% relative humidity (RH) for 5 days through Maillard reaction between the ε-amino of lysine in soy proteins and the reducing-end carbonyl residue in the dextran. The covalent attachment of dextran to SAPP was confirmed by SDS-polyacrylamide gel electrophoresis and gel filtration chromatography. Functional properties of soy protein depend on the structural and aggregation characteristics of their major components (storage globulins 7S and 11S). The conjugate seemed to be predominantly formed by 7S, and the acidic subunits of 11S in soy protein. The emulsifying properties of the SAPP–dextran conjugate were about four times higher than those of SAPP. The solubility of the protein was not enhanced as a result of preheating, but rather it was not decreased when the conjugated protein was heated at 90 °C for 20 min due to the presence of the polysaccharide. The excellent emulsifying properties of SAPP–dextran conjugate were maintained even at pH 3.0 and were further improved at pH 10.0. The object of Maillard reaction is to guarantee the suitable reaction degree, and the resulting soluble conjugate can have excellent emulsifying properties. 相似文献
992.
Cheng Guoguang Liao Nengbin School of Metallurgy University of Science Technology Beijing Beijing P. R. China 《中国有色金属学会会刊》1998,(3)
1INTRODUCTIONItisofgreatimportancefortheestimationofsurfacetensionforaloymelt.Manymetalurgyphenomena,suchasCObubblesgenerati... 相似文献
993.
旋挤加工法是利用一种特殊旋挤头作高速旋转,使工件材料发生热塑性变形面直接形成翻边孔的无切屑加工。文中叙述旋挤法加工翻边孔的成形过程中旋挤头轴向压力、变形区温度的变化以及翻边孔成形后工件材料组织与性能的变化等。 相似文献
994.
995.
C.W. Liao 《Powder Technology》2009,189(3):508-513
A new online automatic optical inspection system (OAOIS) using digital image processing has been developed to measure the coarse particle size distribution. The OAOIS is composed of particle separation module, image acquisition module, image processing and analysis module and PC/PLC-based electric control module. Experiments were performed with non-uniform particles (1-100 mm). The particle size distribution, number of the particles, and accumulated weight percentages of particles are obtained by using the developed system. The experimental results show that the repeated precision of accumulated weight percentages is around ± 1%. To improve the reliability and accuracy of the OAOIS measuring results, the linear regression equation is applied to mapping the result of OAOIS to that of traditional net sieving system (TNSS). It has been shown that the developed system has a high accuracy and precision for coarse particle sizing distribution. 相似文献
996.
Formation of acid‐precipitated soy protein–dextran conjugates by Maillard reaction in liquid systems
Jun‐ru Qi Jin‐song Liao Shou‐wei Yin JianHua Zhu Xiao‐quan Yang 《International Journal of Food Science & Technology》2010,45(12):2573-2580
The conjugation reaction between soybean acid‐precipitated protein (SAPP) and dextran in liquid systems via the initial stage of the Maillard reaction was studied. Functional SAPP–dextran conjugates were prepared in 80% ethanol‐reacting system at 50 °C for 6 h, along with 95% ethanol‐reacting system at 60 °C for 24 h. The covalent attachment of dextran to SAPP was confirmed by sodium dodecyl sulphate–polyacrylamide gel electrophoresis and gel filtration chromatography.Compared to the classical dry‐heating, the reaction time of glycosylation in the two ethanol systems was largely shortened. Emulsifying activity of SAPP–dextran conjugates obtained by dry‐heating incubation and in ethanol was similar at pH 7.0 and10.0, significantly higher than that of SAPP–dextran mixture or SAPP alone. In addition, SAPP–dextran conjugates obtained in 80% ethanol‐reacting system for 6 h were completely soluble after heating at 90 °C for 20 min. The impact of various processing conditions on the formation of SAPP–dextran conjugates was investigated. This study provides important guidance to create protein–polysaccharide conjugates at mild temperatures in liquid systems. 相似文献
997.
A new kind of aqueous drag-reducing fluid with carbon nanotubes (CNTs) was developed. The new working fluid was an aqueous CTAC (cetyltrimethyl ammonium chloride) solution with CNTs added and has both special effects of drag-reducing and heat transfer enhancement. The thermophysical and rheological properties of the new working fluid were measured. An experiment was carried out to investigate the forced convective flow and heat transfer characteristics of conventional drag-reducing fluid (aqueous CTAC solution) and the new drag-reducing nanofluid in a test tube having an inner diameter of 25.6 mm. Results indicated that there were no obvious differences of the drag-reducing characteristics between conventional drag-reducing fluid and new drag-reducing nanofluid. However, there were obvious differences of the heat transfer characteristics between both fluids. The heat transfer characteristics of new drag-reducing nanofluid have strong dependences on the liquid temperature, the nanoparticle concentration and the CTAC concentration. The heat transfer enhancement technology of nanofluid could be used to solve the problem of heat transfer deterioration for conventional drag-reducing fluids. 相似文献
998.
大庆石化公司炼油厂二重催MIP改造空冷器平台整体提升施工难度较大,经过分析、计算、方案对比,提出采用千斤顶同步顶升方法替代传统的吊装工艺,顺利的完成了260 t重的空冷器平台整体提升任务,不仅节约施工成本,同时还探索出一条化工装置有限空间施工的新途径。 相似文献
999.
1000.