全文获取类型
收费全文 | 174篇 |
免费 | 5篇 |
国内免费 | 1篇 |
专业分类
化学 | 145篇 |
晶体学 | 2篇 |
数学 | 11篇 |
物理学 | 22篇 |
出版年
2024年 | 2篇 |
2023年 | 2篇 |
2022年 | 10篇 |
2021年 | 4篇 |
2020年 | 6篇 |
2019年 | 6篇 |
2018年 | 4篇 |
2017年 | 5篇 |
2016年 | 11篇 |
2015年 | 3篇 |
2014年 | 7篇 |
2013年 | 14篇 |
2012年 | 12篇 |
2011年 | 11篇 |
2010年 | 9篇 |
2009年 | 11篇 |
2008年 | 7篇 |
2007年 | 8篇 |
2006年 | 9篇 |
2005年 | 9篇 |
2004年 | 6篇 |
2003年 | 2篇 |
2002年 | 10篇 |
2001年 | 1篇 |
2000年 | 1篇 |
1998年 | 1篇 |
1996年 | 1篇 |
1994年 | 2篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1987年 | 1篇 |
1976年 | 1篇 |
1972年 | 1篇 |
排序方式: 共有180条查询结果,搜索用时 15 毫秒
1.
2.
Summary Dioxomolybdenum(VI) complexes [MoO2L]H2O and oxomolybdenum(V) complexes [Mo2O3L2]H2O and [Mo2O3(LH)2(OH)2(H2O)2] (where LH2=thiocarbohydrazones derived from thiocarbohydrazide with salicylaldehyde, 5-methyl-, 5-chloro-, 5-bromo-, 3-methoxysalicylaldehyde and 2-hydroxy-1-naphthaldehyde) have been prepared and characterised by elemental analysis, conductivity, magnetic moment, i.r., u.v-vis, e.p.r. and thermal studies. The data suggests that molybdenum(VI) complexes are non electrolytes, diamagnetic, monomeric and have distorted octahedral geometry, whereas the molybdenum(V) complexes are non electrolytes, paramagnetic and have distorted octahedral structures with possible metal intereaction via oxo bridging. 相似文献
3.
4.
The conventional condensation and refluxing process was employed to synthesize Ni(II) and Cu(II) complexes of Methylcarbamatethiosemicarbazone ligand. Reactions were carried out at the pH of 7. The molar ratio of the ligand and metal salt was 2:1. The structures of the synthesized metal complexes were suggested by different analytical techniques such as magnetic susceptibility, molar conductance, IR, EPR and UV spectroscopy. Experimental studies confirmed the octahedral geometry for all the complexes. The geometry of the ligand and complexes were also confirmed by theoretical studies. The complexes were investigated for biological action against pathogenic fungi (C. krusei, C. albican) and bacteria (S. aureus, E. coli). The antimicrobial results confirmed superior inhibition potential of the metal complexes as compared with the parent ligand. The enhanced antimicrobial activities might be due to the chelation. Molecular-docking assays confirmed the strong interaction of ligand with target antimicrobial protein DNA gyrase-B. 相似文献
5.
Pallavi Singh Rakesh Tripathi Rajiv K. Verma Ganesh C. Nandi Ashutosh Gupta Maya S. Singh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(10):2142-2151
A simple and efficient synthesis of previously unknown benzosubstituted dioxaphosphonines containing a quinoxaline subunit is described. Reasonably good yields of the products, mild reaction conditions, and convenient work-up are the advantages of this method. The procedure does not require any catalyst or activator and can be efficiently achieved via dianion cyclization. All the synthesized compounds have been characterized by satisfactory elemental analyses and spectral (IR, 1H, 13C, 31P NMR, and mass) studies. Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. 相似文献
6.
Suresh B. Waghmode Ganesh Mahale Viraj P. Patil Kartik Renalson Dharmendra Singh 《合成通讯》2013,43(24):3272-3280
A rapid method for selective cleavage of aryl methylethers can be achieved in the presence of a protic acid and a catalytic amount of phase-transfer catalyst (Aliquat-336). Aliquat-336 accelerates the rate of reaction and affords the corresponding phenols in excellent to good yields on a wide variety of substrates. [Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.] 相似文献
7.
Prachi Vilekar Catherine King Pallavi Lagisetty Vibhudutta Awasthi Shanjana Awasthi 《Applied biochemistry and biotechnology》2014,172(7):3363-3373
Curcumin is well known for its antimicrobial and anti-inflammatory properties. However, since systemic absorption and bioavailability of curcumin from gastrointestinal tract is considerably poor, synthetic curcuminoids are being developed as better alternatives. Two curcumin derivatives: 3,5-bis(benzylidene)-4-piperidone (EF24) and EF24-dimer linked via diethylenetriaminepentacetic acid (EF2DTPA), were included in this study. We investigated the antibacterial activity of EF24 and EF2DTPA against Gram-negative (Escherichia coli) and Gram-positive (Enterococcus faecalis, Staphylococcus aureus) bacteria. We also studied the effects of EF24 and EF2DTPA on uptake and localization of pHrodo-labeled E. coli in the acidic compartments (phagolysosomes) of dendritic cells (DCs) under in vitro conditions. Our results demonstrate that treatment with EF24 and EF2DTPA directly suppresses the bacterial growth. However, these compounds do not affect the bacterial uptake or localization in the DCs. 相似文献
8.
9.
Mixed ionic and electronic conductivity of three solid charge transfer (CT) complexes of pyridine, 4-methylpyridine (γ-picoline) and 3,5-dimethylpyridine (3,5-lutidine) with ICl (iodine monochloride) are reported. Electrical parameters of the prepared complexes in the pellet form are evaluated at various temperatures and at wide frequency range by employing AC complex impedance spectroscopic technique. Suitable equivalent circuits for the Nyquist plots, which provide the most realistic model of the electrical properties of the CT complexes, have been suggested. Both transport number measurements and impedance spectra reveal that the conduction in γ-picoline-ICl complex is mainly due to ions, in 3,5-dimethylpyridine-ICl complex, it is due to both ions and electrons and in pyridine-ICl complex, it is predominantly due to electrons. The a.c. conductivity measurements of the CT complexes have been carried out in the frequency range of 10–105 Hz within the temperature range of 303–353 K. The variation of a.c. conductivity with frequency follows the Jonscher’s universal power law. The temperature dependence of electrical conductivity suggests the semiconducting behaviour of the materials. 相似文献
10.
Chavan SP Sharma P Sivappa R Bhadbhade MM Gonnade RG Kalkote UR 《The Journal of organic chemistry》2003,68(17):6817-6819
Introduction of natural menthol as the chiral auxiliary in a gamma-Br-alpha,beta-unsaturated ester leads to enantioselective generation of three chiral centers in a single step on reaction with a glycine anion equivalent to provide L-CCG-I in 94% ee. 相似文献