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91.
92.
Vasanthy Arasaratnam Ketheeswary Mylvaganam & Kandiah Balasubramaniam 《International Journal of Food Science & Technology》1997,32(4):299-304
Aspergillus niger CFTRI 1105 was cultivated on solid medium for glucoamylase production. Glucoamylase activity obtained was 83.7 U g−1 DFR (Dry Fermentation Residue) in a medium containing rice bran (100 g), corn flour (2 g), stock mineral solution (10 mL) and tap water (90 mL). When corn flour (2 g) in the medium was substituted with soya flour (2 g) no significant increase in glucoamylase was observed. The effects of soya flour, urea and peptone at the same elemental nitrogen concentration as with corn flour as carbon source on glucoamylase production were investigated. Supplementation with soya flour gave the highest glucoamylase activity (121 U g−1 DFR) at 72 h and addition of paddy husk to a medium containing corn and soya flour altered the enzyme production from 121 U g−1 DFR to 71.3 U g−1 DFR. Addition of gingili oil and coconut oil to the medium caused no improvement in glucoamylase production. 相似文献
93.
BACKGROUND: Gluten peptide was prepared by trypsin hydrolysis and characterized by high‐performance liquid chromatographic analysis. The effects on non‐frozen and frozen doughs of trypsin‐hydrolyzed gluten peptide (THGP) and its combination with ascorbic acid or KBrO3 were investigated. RESULTS: Molecular analysis of THGP showed a decrease in the high‐molecular‐weight and an increase in the low‐molecular‐weight sodium dodecyl sulfate‐soluble fractions, compared with those of control wheat gluten. The addition of 8% THGP decreased the mixing time and tolerance of the dough, both with and without ascorbic acid or KBrO3. However, the maximum resistance and extensibility of the rested dough containing 8% THGP, with and without ascorbic acid or KBrO3, were not significantly different from those of the control dough. The addition of 8% THGP significantly increased the loaf volume of bread baked from non‐frozen dough when combined with 60 ppm ascorbic acid or 30 ppm KBrO3, but it had a significant effect both with and without ascorbic acid or KBrO3 on frozen‐dough bread. A large difference in volume was observed between breads made with and without THGP at the oven‐spring, rather than at proofing. CONCLUSION: The addition of 8% THGP increased the loaf volume of bread made from freeze‐damaged dough and this effect increased when THGP was combined with 60 ppm ascorbic acid. Copyright © 2008 Society of Chemical Industry 相似文献
94.
根据仪长线管输混合油的胶质沥青质含量和蜡烃碳数分布,合成了颗粒状油溶性原油降黏剂BEM-JN。该剂由醇烃基碳数为16~22的丙烯酸高级醇酯、顺丁烯二酸酐、丙烯酰胺三元共聚物、硬脂酸和二乙烯三胺的酰胺及多种表面活性剂组成。简介了合成方法。在室内测试中,加量60 mg/L的BEM-JN使混合原油凝点由4℃降至-10℃,低温(20,15,10,7℃)黏度大幅降低。在管径559×7.9(mm)、长87 km的仪长线大冶~武汉支线上进行了为期5天的现场测试,地温15℃,在大冶起点站加入60 mg/L BEM-JN后,混合原油的凝点和黏度(平均值)由9℃和1059.6 mPa.s降至-4℃和388.5 mPa.s,到达武汉终点站后为-9.5℃和428.0 mPa.s,停输33小时后再启输,到达终点站后为-9~-10℃和411.6~443.4 mPa.s。表3参3。 相似文献
95.
原油流动性改进剂的制备及应用 总被引:4,自引:0,他引:4
以烯烃、烯烃基脂肪酸酯和烯属不饱和酰胺或烯属烃磺酸盐为主要原料,合成了含蜡原油降凝剂H89-2(三元共聚物)。综合评定了H89-2改善青海原油流动性能的效果。阐明了确定降凝剂最佳添加量的原则。 相似文献
96.
Synthesis and Evaluation of Some C14MC-MCNR2 Copolymers and C14MC-MA-MCNR2 Terpolymers as Cold Flow Improvers in the Diesel Fuels 总被引:1,自引:0,他引:1
In order to find efficient cold flow improvers for diesel fuels, a series of copolymers (C14MC-MCNR2) derivated from long chain alkyl (i.e., tetradecyl) methacrylate C14MC and methacrylamide (MCNR2) were prepared, and a series of terpolymers (C14MC-MA-MCNR2) derivated from tetradecyl methacrylate C14MC, maleic anhydride (MA), and methacrylamide (MCNR2) were also prepared. These copolymers and terpolymers were purified, and their structures were characterized by IR, 1HNMR, and GPC. Their low temperature fluidities and filterability, such as solid point depression (ΔSP) and cold filter plugging point depression (ΔCFPP), used as cold flow improvers in two diesel fuels were evaluated. The results indicate that: (1) The C14MC-MCNR2 copolymers possess good solid point depressing performance. (2) The C14MC-MA-MCNR2 terpolymers exhibit dual function both as wax dispersants and flow improvers simultaneously, and they all possess very excellent solid point depressing performance, and can attain optimum effectiveness of CFPP depression when NR2 is morpholine. 相似文献
97.
和面、绞肉、拌馅三用机是一种多功能的食品机械,降低了费用,减少了占地面积,大大满足中小型餐馆的使用。 相似文献
98.
99.
Gloria Urbano María López‐Jurado Jesús M Porres Sławomir Frejnagel Elena Gómez‐Villalva Juana Frías Concepción Vidal‐Valverde Pilar Aranda 《Journal of the science of food and agriculture》2007,87(7):1356-1363
The effect of treatment with α‐galactosidase, tannase or a cell‐wall‐degrading enzyme complex under optimal conditions of pH, temperature and length of incubation time on the chemical composition and nutritive utilisation of protein and carbohydrates from pea (Pisum sativum L.) flour was studied. Soaking of pea flours in combination with enzyme treatment led to reductions of 77–90% in the levels of α‐galactosides, and of 60–80% in the levels of trypsin inhibitor activity, increasing the content of total available sugars, which was highest in the pea flour treated with the cell‐wall‐degrading enzyme complex. All the treatments assayed caused a significant improvement in daily food intake, whereas the nutritive utilisation of protein was not increased in any of the pea products tested when compared to the raw pea flour. However, all the soaking and enzymatic treatments led to a significant improvement in daily weight gain associated with a higher dietary intake of food and total available sugars. Copyright © 2007 Society of Chemical Industry 相似文献
100.