全文获取类型
收费全文 | 643篇 |
免费 | 38篇 |
国内免费 | 8篇 |
专业分类
化学 | 331篇 |
晶体学 | 4篇 |
力学 | 17篇 |
数学 | 257篇 |
物理学 | 80篇 |
出版年
2023年 | 7篇 |
2022年 | 22篇 |
2021年 | 30篇 |
2020年 | 33篇 |
2019年 | 41篇 |
2018年 | 34篇 |
2017年 | 37篇 |
2016年 | 42篇 |
2015年 | 28篇 |
2014年 | 33篇 |
2013年 | 55篇 |
2012年 | 36篇 |
2011年 | 40篇 |
2010年 | 31篇 |
2009年 | 24篇 |
2008年 | 32篇 |
2007年 | 28篇 |
2006年 | 17篇 |
2005年 | 13篇 |
2004年 | 17篇 |
2003年 | 17篇 |
2002年 | 15篇 |
2001年 | 4篇 |
2000年 | 3篇 |
1999年 | 1篇 |
1998年 | 2篇 |
1997年 | 4篇 |
1996年 | 1篇 |
1994年 | 4篇 |
1993年 | 1篇 |
1991年 | 1篇 |
1989年 | 1篇 |
1988年 | 2篇 |
1987年 | 2篇 |
1985年 | 2篇 |
1982年 | 2篇 |
1979年 | 1篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1976年 | 5篇 |
1975年 | 2篇 |
1974年 | 3篇 |
1973年 | 5篇 |
1971年 | 1篇 |
1970年 | 1篇 |
1968年 | 1篇 |
排序方式: 共有689条查询结果,搜索用时 15 毫秒
1.
2.
Johannes C. B. Dietschreit Annika Wagner T. Anh Le Philipp Klein Prof. Dr. Hermann Schindelin Prof. Dr. Till Opatz Prof. Dr. Bernd Engels Prof. Dr. Ute A. Hellmich Prof. Dr. Christian Ochsenfeld 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(31):12769-12773
The absence of fluorine from most biomolecules renders it an excellent probe for NMR spectroscopy to monitor inhibitor–protein interactions. However, predicting the binding mode of a fluorinated ligand from a chemical shift (or vice versa) has been challenging due to the high electron density of the fluorine atom. Nonetheless, reliable 19F chemical-shift predictions to deduce ligand-binding modes hold great potential for in silico drug design. Herein, we present a systematic QM/MM study to predict the 19F NMR chemical shifts of a covalently bound fluorinated inhibitor to the essential oxidoreductase tryparedoxin (Tpx) from African trypanosomes, the causative agent of African sleeping sickness. We include many protein–inhibitor conformations as well as monomeric and dimeric inhibitor–protein complexes, thus rendering it the largest computational study on chemical shifts of 19F nuclei in a biological context to date. Our predicted shifts agree well with those obtained experimentally and pave the way for future work in this area. 相似文献
3.
Tuan Anh Pham 《International journal of quantum chemistry》2019,119(1):e25795
Understanding physicochemical properties of liquid electrolytes is essential for predicting and optimizing device performance for a wide variety of emerging energy technologies, including photoelectrochemical water splitting, supercapacitors, and batteries. In this work, we review recent progress and open challenges in predicting structural, dynamical, and electronic properties of the liquids using first-principles approaches. We briefly summarize the basic concepts of first-principles molecular dynamics (FPMD), and we discuss how FPMD methods have enriched our understanding of a number of liquids, including aqueous solutions, organic electrolytes and ionic liquids. We also discuss technical challenges in extending FPMD simulations to the study of liquid electrolytes in more complex environments, including the interface between electrolytes and electrodes, which is a key component in many energy storage and conversion systems. 相似文献
4.
5.
Differential Equations - We consider compact difference schemes of approximation order $$4+2 $$ on a three-point spatial stencil for the Klein–Gordon equations with constant and variable... 相似文献
6.
Oncogenic MicroRNAs Biogenesis as a Drug Target: Structure–Activity Relationship Studies on New Aminoglycoside Conjugates 下载免费PDF全文
7.
8.
Anh N. Hong Diana Luong Mohammed Alghamdi Wei-Cheng Liao Weiyi Zhang Emily Kusumoputro Yichong Chen Prof. P. Alex Greaney Prof. Yongtao Cui Prof. Jing Shi Prof. Xianhui Bu Prof. Boniface P. T. Fokwa Prof. Pingyun Feng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(52):e202201576
Two new rod-packing metal–organic frameworks (RPMOF) are constructed by regulating the in situ formation of the capping agent. In CPM-s7, carboxylate linkers extend 1D manganese-oxide chains in four additional directions, forming 3D RPMOF. The substitution of Mn2+ with a stronger Lewis acidic Co2+, leads to an acceleration of the hydrolysis-prone sulfonate linker, resulting in presence of sulfate ions to reduce two out of the four carboxylate-extending directions, and thus forming a new 2D rod-packing CPM-s8. Density functional theory calculations and magnetization measurements reveal ferrimagnetic ordering of CPM-s8, signifying the potential of exploring 2D RPMOF for effective low-dimensional magnetic materials. 相似文献
9.
A dynamic mathematical model is developed for production of Cerenol polyether from 1,3‐propanediol in a batch reactor system. The model accounts for polycondensation reactions and side reactions in the liquid phase and for mass transfer of volatile species to the vapor. Parameters are estimated using measured liquid‐phase concentrations of monomer, oligomers, water, and end groups as well as the mass and composition of condensate collected from the overhead condenser system. The proposed model uses novel probability factors to keep the model equations relatively simple while accounting for the complex influence of superacid catalyst on reaction rates. The model is a significant advance over previous Cerenol models because it better accounts for mass‐transfer rates and for the dynamic behavior of the condenser. In addition, the proposed model accounts for the inhibitory influence of water on polycondensation kinetics due to hydration of hydroxyl ends. The model equations and parameter estimates provide a substantial improvement in fit to the data, especially for long reaction times and high catalyst levels, resulting in a 97% reduction in the value of the weighted least squared objective function compared to equations and parameters from a previous model. 相似文献
10.
Kun Lan Ruicong Wang Qiulong Wei Yanxiang Wang Anh Hong Pingyun Feng Dongyuan Zhao 《Angewandte Chemie (International ed. in English)》2020,59(40):17676-17683
By introducing a compatible reducing agent (2‐ethylimidazole) into a mono‐micelle assembly process, we present a type of ordered mesoporous TiO2 microspheres that combines radially aligned mesostructure with Ti3+ defects in mesoporous frameworks. Such reductant acts as a building block of mesostructured frameworks and reduces Ti4+ in situ to generate defects during calcination, giving rise to the coexistence of bulk Ti3+ defects and an ordered mesostructure. The mesoporous TiO2 has both excellent mesoporosity (a high surface area of 106 m2 g?1, a mean pore size of 18.4 nm) and stable defects with an extended photoresponse. Such integration of unique mesoscopic architecture and atomic vacancies provide both effective mass transportation and enhanced light utilization, leading to a remarkable increase in H2 generation rate. A maximum H2 evolution rate of 19.8 mmol g?1 h?1 can be achieved, along with outstanding stability under solar light. 相似文献