首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   613篇
  免费   6篇
化学   284篇
晶体学   10篇
力学   13篇
数学   181篇
物理学   131篇
  2023年   5篇
  2022年   9篇
  2021年   14篇
  2019年   8篇
  2018年   10篇
  2017年   6篇
  2016年   21篇
  2014年   21篇
  2013年   33篇
  2012年   32篇
  2011年   28篇
  2010年   25篇
  2009年   20篇
  2008年   35篇
  2007年   27篇
  2006年   16篇
  2005年   15篇
  2004年   9篇
  2003年   14篇
  2002年   10篇
  2001年   7篇
  2000年   11篇
  1998年   6篇
  1994年   6篇
  1992年   4篇
  1990年   4篇
  1988年   4篇
  1984年   6篇
  1983年   6篇
  1982年   8篇
  1981年   4篇
  1980年   8篇
  1978年   5篇
  1974年   4篇
  1973年   7篇
  1966年   8篇
  1965年   6篇
  1964年   4篇
  1962年   5篇
  1959年   5篇
  1958年   9篇
  1957年   8篇
  1956年   8篇
  1955年   10篇
  1954年   10篇
  1941年   6篇
  1940年   5篇
  1939年   4篇
  1936年   10篇
  1935年   6篇
排序方式: 共有619条查询结果,搜索用时 0 毫秒
21.
22.
23.
The measurement of powder flowability is a major concern for most industrial processes that deal with the handling of bulk solids as raw materials,intermediates,or products.The development of devices that measure the flowability of non-aerated powders has not progressed as rapidly as might have been hoped since most research activities have been based on various types of shear testers intended to aid the design of hoppers.A new flowability indicator named as weighted cohesion (WS) is established using newly...  相似文献   
24.
25.
New heterocyclic derivatives of 9‐azajulolidine have been synthesized and characterized with respect to their nucleophilicity and Lewis basicity. The Lewis basicity of these bases as quantified through their theoretically calculated methyl‐cation affinities correlate well with the experimentally measured reaction rates for addition to benzhydryl cations. All newly synthesized pyridines show exceptional catalytic activities in benchmark acylation reactions, which correlate only poorly with Lewis basicity or nucleophilicity parameters. A combination of Lewis basicity with charge and geometric parameters in the framework of a three‐component quantitative structure–activity relationship (QSAR) model is, however, highly predictive.  相似文献   
26.
Russian Journal of Electrochemistry - The effect of temperature and discharge rate on the discharge capacity of nickel–cadmium (Ni?Cd) cell is investigated quantitatively. Ni–Cd...  相似文献   
27.
The study aimed to investigate the antibacterial activity of Mustard (Brassica juncea) and Moringa (Moringa oleifera) leaf extracts and coagulant protein for their potential application in water treatment. Bacterial cell aggregation and growth kinetics studies were employed for thirteen bacterial strains with different concentrations of leaf extracts and coagulant protein. Moringa oleifera leaf extract (MOS) and coagulant protein showed cell aggregation against ten bacterial strains, whereas leaf extract alone showed growth inhibition of five bacterial strains for up to 6 h and five bacterial strains for up to 3 h. Brassica juncea leaf extract (BJS) showed growth inhibition for up to 6 h, and three bacterial strains showed inhibition for up to 3 h. The highest inhibition concentration with 2.5 mg/mL was 19 mm, and furthermore, the minimum inhibitory concentration (MIC) (0.5 mg/mL) and MBC (1.5 mg/mL) were determined to have a higher antibacterial effect for <3 KDa peptides. Based on LCMS analysis, napin was identified in both MOS and BJS; furthermore, the mode of action of napin peptide was determined on lipoprotein X complex (LpxC) and four-chained structured binding protein of bacterial type II topoisomerase (4PLB). The docking analysis has exhibited moderate to potent inhibition with a range of dock score −912.9 Kcal/mol. Thus, it possesses antibacterial-coagulant potential bioactive peptides present in the Moringa oleifera purified protein (MOP) and Brassica juncea purified protein (BJP) that could act as an effective antimicrobial agent to replace currently available antibiotics. The result implies that MOP and Brassica juncea purified coagulant (BJP) proteins may perform a wide degree of antibacterial functions against different pathogens.  相似文献   
28.
Specific immune detection of glycated hemoglobin is still a great challenge owing to the small epitopic difference between Hemoglobin (Hb) and HbA1c. We report a new electrochemical immunoassay format for point of care testing of HbA1c. A conducting self‐assembled monolayer of mercaptophenyl boronic acid (MPBA) was used as a capture layer for binding of glycated proteins and ferrocene tagged anti‐HbA1c antibody (FcAb) as a tracer molecule on a gold screen printed electrode. Validation of the new HbA1c assay was carried out using 6 clinical samples with known HPLC values and a correlation coefficient of 98 % was observed.  相似文献   
29.
30.
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号