收费全文 | 778篇 |
免费 | 18篇 |
国内免费 | 4篇 |
化学 | 575篇 |
晶体学 | 11篇 |
力学 | 2篇 |
数学 | 70篇 |
物理学 | 142篇 |
2023年 | 5篇 |
2022年 | 4篇 |
2021年 | 8篇 |
2020年 | 17篇 |
2019年 | 15篇 |
2018年 | 6篇 |
2017年 | 19篇 |
2016年 | 10篇 |
2015年 | 16篇 |
2014年 | 18篇 |
2013年 | 62篇 |
2012年 | 60篇 |
2011年 | 49篇 |
2010年 | 31篇 |
2009年 | 25篇 |
2008年 | 40篇 |
2007年 | 49篇 |
2006年 | 42篇 |
2005年 | 47篇 |
2004年 | 26篇 |
2003年 | 41篇 |
2002年 | 18篇 |
2001年 | 14篇 |
2000年 | 14篇 |
1999年 | 12篇 |
1998年 | 9篇 |
1997年 | 8篇 |
1996年 | 11篇 |
1994年 | 9篇 |
1993年 | 3篇 |
1992年 | 5篇 |
1991年 | 4篇 |
1990年 | 7篇 |
1989年 | 4篇 |
1988年 | 3篇 |
1987年 | 5篇 |
1986年 | 4篇 |
1985年 | 13篇 |
1984年 | 12篇 |
1983年 | 2篇 |
1982年 | 11篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 16篇 |
1978年 | 7篇 |
1977年 | 5篇 |
1975年 | 2篇 |
1974年 | 2篇 |
1973年 | 1篇 |
1971年 | 1篇 |
The role of valence electrons for the muon capture process by molecules is experimentally investigated with the aid of cascade calculations. Low-momentum muons are introduced to gas targets of CO, CO2, and COS below atmospheric pressure. The initial states of captured muons are determined from the measured muonic X-ray structure of the Lyman and Balmer series. We propose that the lone pair electrons in the carbon atom of CO significantly contribute to the capture of a muon with large angular momenta.
相似文献The anion exchange reaction is fundamental to the adsorption and desorption of a specific species from a solution phase to an extracting phase, and it is widely used for separation and waste fluid treatment in industrial fields. However, the details of the anion exchange reaction are poorly understood. Quantitative thermodynamic analysis needs a precise solution condition before and after the exchange reaction. Identification of species adsorbed on the anion exchanger is also necessary because there are multiple species in the solution phase in general. Cobalt is a base metal that is widely used in modern society. One of the authors determined the distribution of cobalt-chloro complexes in hydrochloric acid solutions. It is necessary to know what species are adsorbed on anion exchangers for the thermodynamic analysis of the anion exchange reaction. The comparison in structures between the species in the solution phase and adsorbed on anion exchangers reveals what species are adsorbed. Therefore, the determination of the structures of cobalt-chloro complexes in the solution phase is the next step for quantitative analysis. X-ray absorption spectroscopy (XAS) was used for the structure analysis. Factor analysis can decompose extended X-ray absorption fine structure (EXAFS) and X-ray absorption near-edge structure (XANES) spectra consisting of multiple species into individual spectra of single species using the distribution determined using UV-Vis absorption spectra. Fitting EXAFS theoretical models to the decomposed individual spectra determined the structures of three cobalt-chloro complexes: an octahedron of [CoII(H2O)6]2+, a distorted octahedron of [CoII(H2O)5Cl]+, and a tetrahedron of [CoIICl4]2?. The XANES spectra showed us that the Cl ligand in [CoII(H2O)5Cl]+ was attracted to the center atom of CoII by an electrostatic force, and the bonding system between Cl ligands and CoII in [CoIICl4]2? involved covalency.
相似文献![点击此处可从《Chemistry (Weinheim an der Bergstrasse, Germany)》网站下载免费的PDF全文](/ch/ext_images/free.gif)