全文获取类型
收费全文 | 13652篇 |
免费 | 942篇 |
国内免费 | 218篇 |
专业分类
电工技术 | 457篇 |
技术理论 | 1篇 |
综合类 | 493篇 |
化学工业 | 2683篇 |
金属工艺 | 399篇 |
机械仪表 | 515篇 |
建筑科学 | 731篇 |
矿业工程 | 226篇 |
能源动力 | 392篇 |
轻工业 | 2352篇 |
水利工程 | 194篇 |
石油天然气 | 488篇 |
武器工业 | 52篇 |
无线电 | 964篇 |
一般工业技术 | 2140篇 |
冶金工业 | 758篇 |
原子能技术 | 70篇 |
自动化技术 | 1897篇 |
出版年
2024年 | 45篇 |
2023年 | 185篇 |
2022年 | 284篇 |
2021年 | 480篇 |
2020年 | 374篇 |
2019年 | 370篇 |
2018年 | 498篇 |
2017年 | 553篇 |
2016年 | 496篇 |
2015年 | 466篇 |
2014年 | 651篇 |
2013年 | 1091篇 |
2012年 | 874篇 |
2011年 | 953篇 |
2010年 | 783篇 |
2009年 | 722篇 |
2008年 | 752篇 |
2007年 | 697篇 |
2006年 | 677篇 |
2005年 | 456篇 |
2004年 | 370篇 |
2003年 | 362篇 |
2002年 | 322篇 |
2001年 | 318篇 |
2000年 | 268篇 |
1999年 | 254篇 |
1998年 | 318篇 |
1997年 | 234篇 |
1996年 | 174篇 |
1995年 | 161篇 |
1994年 | 126篇 |
1993年 | 85篇 |
1992年 | 58篇 |
1991年 | 43篇 |
1990年 | 35篇 |
1989年 | 35篇 |
1988年 | 35篇 |
1987年 | 17篇 |
1986年 | 20篇 |
1985年 | 22篇 |
1984年 | 24篇 |
1983年 | 28篇 |
1982年 | 20篇 |
1981年 | 8篇 |
1980年 | 11篇 |
1979年 | 8篇 |
1977年 | 10篇 |
1976年 | 12篇 |
1975年 | 5篇 |
1973年 | 5篇 |
排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
焦化行业由于具有耗水量大、污染物成分复杂、环境污染严重等特点,严重影响着社会环境及地区发展。随着《炼焦化学工业污染物排放标准》(GB 16171—2012)的实施,对焦化废水的深度处理成为各企业亟待解决的难题。着重介绍了全膜法在焦化废水深度处理中的应用情况,一年来的运行效果表明该方法对经生化处理后的焦化废水进行再回收利用有着良好的应用效果。 相似文献
992.
993.
Dr. Alberto Fernández‐Tejada Prof. Dr. F. Javier Cañada Prof. Dr. Jesús Jiménez‐Barbero 《ChemMedChem》2015,10(8):1291-1295
The biological relevance of glycans as mediators of key physiological processes, including disease‐related mechanisms, makes them attractive targets for a wide range of medical applications. Despite their important biological roles, especially as molecular recognition elements, carbohydrates have not been fully exploited as therapeutics mainly due to the scarcity of structure–activity correlations and their non‐drug‐like properties. A more detailed understanding of the complex carbohydrate structures and their associated functions should contribute to the development of new glycan‐based pharmaceuticals. Recent significant progress in oligosaccharide synthesis and chemical glycobiology has renewed the interest of the medicinal chemistry community in carbohydrates. This promises to increase our possibilities to harness them in drug discovery efforts for the development of new and more effective, synthetic glycan‐based therapeutics and vaccines. 相似文献
994.
Ruben Ramírez‐Gómez Daniel García‐Cortés Gaston Martínez‐de Jesús Margarita M. González‐Brambila Alejandro Alonso Sergio A. Martínez‐Delgadillo Jorge Ramírez‐Muñoz 《化学工程与技术》2015,38(9):1519-1529
High‐shear impellers (HSIs) are mixers used in industrial stirred tanks to incorporate powders into liquids and break down particle agglomerates. A detailed numerical study of two commercial ring‐style HSIs of laboratory scale was carried out and their performance was compared with the Rushton turbine (RT). It was found that power and pumping numbers or their ratio cannot be simply connected for properly selecting an impeller in applications where highly localized viscous dissipation is desirable. The ratio of the average viscous dissipation in the impeller swept volume to the mean in the entire volume at two constant values of power input turned out to be lower for HSIs compared to that evaluated for RT. However, at higher power input, the dimensionless average viscous dissipation in the blade swept volume was found to be similar for the HSI of two rings and the RT, corroborating the high local viscous dissipation of this HSI when operated at higher speeds. 相似文献
995.
油页岩低温干馏制取页岩油,其干馏产生的干馏渣和硅铝质原料(煤矸石)的化学成分相近并含有一定发热量。基于此,某新型干法生产线利用干馏渣替代部分硅铝质原料(烧煤矸石、黏土)用于水泥生料配料生产水泥熟料,介绍了其生产操作调整措施。实践证明,干馏渣替代部分硅铝质原料生产水泥是切实可行的,不仅能改善生料易烧性且价格低廉,降低了熟料煤耗和生产成本,具有广阔的市场应用前景。 相似文献
996.
997.
998.
999.
Zhenqi Shi James Hermiller Salvador García Muñoz 《American Institute of Chemical Engineers》2019,65(1):87-98
The Extended Iterative Optimization Technology (EIOT) method is proposed as an extension to Muteki's [I&ECR 2013;52(35):12258–12268] Iterative Optimization Technology to address deviations from Beer–Lambert's law in powders. The new method estimates the apparent spectrum for the pure species, rather than using the measured spectrum and augments Beer–Lambert's law with a bilinear term to capture the signature and strength of the nonchemical interferences. The proposed method has exhibited acceptable performance in spite of using a lean data set to estimate its parameters. The method provides robust and coherent estimates within the physical boundaries of the system and exhibits robustness to instrument transfer. The lean effort needed to build the EIOT method positions it as an attractive option in early stages of pharmaceutical drug product development. Its robustness to distinguish chemical from nonchemical signals implies a potential to lower the total cost of ownership for an EIOT-based solution in manufacturing. © 2018 American Institute of Chemical Engineers AIChE J, 65: 87–98, 2019 相似文献
1000.
The preparation of crosslinked polyimide (PI) composites via a blending technique is reported. Different kinds of organic or inorganic silicon-based nanofillers have been used for this purpose. A comparison is made between carefully chosen pairs of fillers, the choice depending on the compatibility of the crosslinked PI with the filler, to study the effects of the crosslinked PI matrix structure and fillers with different micromorphology. The dispersion of the filler is characterized with SEM as uniformly dispersed or gelled. It is found that with different micromorphology of filler, the PI matrix can be loaded with different mass fractions of filler, and the point at which gelation occurs is not the same. In order to study this behavior, these fillers are subjected to a quadratic mean equation calculation and analysis. Compared to pure PI, all obtained crosslinked composites have a higher glass-transition temperature and a lower dielectric constant. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 46875. 相似文献