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Mohamed Hemida Abd‐Alla Fify Alfy Gabra Amal William Danial Ahmed Mohamed Abdel‐Wahab 《国际能源研究杂志》2019,43(1):391-404
Five facultative anaerobic bacterial isolates were recovered from domestic wastewater. These isolates were identified based on the 16S rRNA as Enterobacter aerogenes (one isolate), Enterobacter cloacae (two isolates), and Cronobacter sakazakii (three isolates). These isolates were examined for their potential to evolve hydrogen on a glucose medium. The most potent hydrogen‐producing isolates, E aerogenes (KY549389) and E cloacae (KY524293), were examined for their capacity to generate hydrogen, acetone, butanol, and ethanol using orange peel (OP) hydrolysate. OP powder was pretreated with n‐hexane to remove the toxicity of d ‐limonene. Different concentrations (4%, 6%, and 8% w/v) of limonene‐free OP were subjected to the boiling water (temperature of 100°C) or acid (HCl) treatments. The maximum fermentative H2 production of 1700 and 1620 mL/L was obtained from 6% OP hydrolysate extracted with boiling water using facultative anaerobic E aerogenes (KY549389) and E cloacae (KY524293), respectively. Hydrogen production efficiency was 0.99 and 1.19 mol H2/mol glucose for E aerogenes and E cloacae, respectively. The total fermentative acetone, butanol, and ethanol (ABE) generated by E aerogenes and E cloacae were 0.78 and 0.38 g/L including acetone (0.05 and 0.04 g/L), butanol (0.011 and 0.013 g/L), and ethanol (0.71 and 0.32 g/L), respectively. The maximum ABE productivity was 0.01 and 0.005 g/L/h generated at 60 g/L OP hydrolysate by E aerogenes and E cloacae, respectively. These strains were positive for nitrogen fixation (nitrogenase) capability estimated by the acetylene reduction assay. Application of OP hydrolysate without the addition of any nutritional components or reducing agent is considered an eco‐friendly, economical, and commercial substrate for desired biofuel production. 相似文献
84.
Rui Yang Huaying Du Ying Sun Fengying Zhang Wei Zhang Chunpeng Wan Jinyin Chen Liqin Zhu 《International Journal of Food Science & Technology》2021,56(10):5259-5267
The present study evaluated the effects of 15 μL L-1 nitric oxide (NO) on the fruit defence response of ‘Newhall’ navel orange. The decay rate of NO-treated navel orange fruits was significantly lower than that of control fruits during storage at 20 °C storage (P < 0.05). Treatment with NO suppressed the increase in disease incidence and lesion area in orange fruits inoculated with Penicillium italicum (P. italicum); significantly increased the activities of phenolic metabolism-associated enzymes and pathogenesis-related (PR) proteins, including polyphenoloxidase (PPO), phenylalanine ammonia-lyase (PAL), β-1,3-glucanase (GLU) and chitinase (CHT); and enhanced the activities of key enzymes, including 4-coumarate: CoA ligase (4CL), cinnamate-4-hydroxylase (C4H) and chalcone isomerase (CHI) in the phenylpropanoid pathway. The contents of total phenolics, flavonoids and lignin were also higher in NO-treated fruits than in control fruits. The findings suggest that exogenous NO could induce disease resistance against P. italicum in navel orange fruits. 相似文献
85.
Training has been identified as an effective tool in the development of human resources, especially in the current context of change. This work aims to analyse the realisation and demand on training courses in the Rioja wine sector in Spain. A representative sample of companies in the sector was interviewed using a questionnaire. Two types of analysis were conducted: univariate and a factorial analysis of variance. These analyses allow using a hypothesis test in which three independent variables are controlled – zone, ownership, and winery size. The results show that the realisation and demand for training are focused on topics related to wine production, and not on marketing. No significant differences were found regarding the realisation and demand for training and the independent variables. 相似文献
86.
In this study, photocatalytic degradation of methyl orange (MO) as an example of organic dye was investigated using different wt% Pd-loaded and N-doped P-25 titanium dioxide (TiO2) nanoparticles, as example of metal and nonmetal-doped TiO2, respectively. The Pd-loaded and N-doped TiO2 photocatalysts were prepared by post-incorporation method using K2PdCl4 and urea, respectively, as precursors. A variety of surface analysis techniques were used for characterization of surface and functional group while using ultraviolet/visible (UV–vis) analysis for monitoring photocatalytic degradation of MO. Kinetic parameters were obtained using Langmuir-Hinshelwood model to determine the degradation rate constants. It was found that the metal-loaded titanium dioxide degraded MO in water at a higher rate than did non-metal-loaded titanium dioxide fabricated by using the post-synthesis method. Also, the pure P25-TiO2 degraded MO more than N-doped TiO2 because of decreased surface area by particle agglomeration after being made by the post-incorporation method. 相似文献
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88.
乳清发酵酒产品是近年来发展起来的新产品。在生产实践中,公司试验研究了乳清发酵酒生产工艺中的消毒技术,按工艺流程的先后顺序,研究了原料消毒、生产环境消毒、生产设备消毒等内容。生产实践证明,这些方法或技术措施的运用,保证了乳清发酵酒的品质,且口味纯正、质量稳定。主要阐述了乳清发酵酒生产过程的消毒技术和措施。 相似文献
89.
Ming Chang Jie Lian Ruijie Liu Qingzhe Jin Xingguo Wang 《International Journal of Food Science & Technology》2014,49(7):1715-1721
Camellia oleifera meal was evaluated to be a potential feedstock for the production of yellow wine (YW), and process conditions were investigated. In this study, C. oleifera meal was firstly pretreated using mixed cultured Bacillus subtilis and Aspergillus niger under solid‐substrate fermentation to degrade the tea saponin (TS) for the following YW fermentation. Response surface methodology helped evaluate the effects of the selected operating parameters, and the optimal condition at a fixed time of 4 days, which gave a 67.84 ± 0.23% degradation rate of TS, was reached as inoculum concentration of 16%, initial moisture content of 55% and temperature of 30 °C. Finally, 7‐day fermentation was harvested to be the most suitable pretreatment for producing YW from C. oleifera meal, and the twice‐feeding fermentation for YW was obtained as wheat koji 12% and active yeast 1.2%. In addition, ample amino acids, phenolic components and the trace TS endowed the C. oleifera wine, the more nutritional characteristics. 相似文献
90.
《Food Control》2014,35(2):274-282
A survey was carried out on a thousand wines from organic viticulture from different European countries. Analytical data were collected about the most used quality control parameters (e.g. alcoholic strength, reducing sugars, total acidity and pH, volatile acidity, malic and lactic acid, free and total sulfur dioxide), as well as regarding some compounds harmful for human health, such as ochratoxin A and biogenic amines. The results collected on quality control parameters were generally in agreement with the values normally detectable for conventional wines. Total sulfur dioxide was lower than 110–120 mg/L in the most of the samples and no significant correlation was found between sulfite levels and other parameters. Ochratoxin A (OTA) seemed not a generalized problem for organic wine productions: its concentration was below the European legal limit, in the 95% of the samples analyzed; nevertheless, the risk of OTA pollution seemed higher in certain southern European regions. On the other hand, biogenic amines (BA) appeared a serious problem for organic winemaking and high concentrations were found in many of the analyzed wines. They seemed connected with a bad management of malolactic fermentation, being generally associated with high pHs and volatile acidities. 相似文献