全文获取类型
收费全文 | 79篇 |
免费 | 4篇 |
专业分类
化学 | 53篇 |
晶体学 | 3篇 |
力学 | 4篇 |
数学 | 10篇 |
物理学 | 13篇 |
出版年
2023年 | 1篇 |
2021年 | 5篇 |
2020年 | 7篇 |
2018年 | 2篇 |
2017年 | 2篇 |
2016年 | 3篇 |
2015年 | 6篇 |
2014年 | 8篇 |
2013年 | 7篇 |
2012年 | 6篇 |
2011年 | 10篇 |
2010年 | 4篇 |
2009年 | 1篇 |
2008年 | 5篇 |
2007年 | 2篇 |
2006年 | 1篇 |
2004年 | 1篇 |
2003年 | 1篇 |
2002年 | 1篇 |
1998年 | 1篇 |
1997年 | 1篇 |
1986年 | 1篇 |
1984年 | 1篇 |
1983年 | 1篇 |
1980年 | 3篇 |
1979年 | 1篇 |
1977年 | 1篇 |
排序方式: 共有83条查询结果,搜索用时 46 毫秒
81.
Three new squarate salts were synthesized and combined with experimental and theoretical study on molecular, vibrational,
and electronical properties. Squaric acid was crystallized as HSQ− [SQ: squarate] monoanion in [(C13H12NO2)(HC4O4)] (I), as uncharged H2SQ in [(C5H5N3O)(H2C4O4)] (II), and as SQ2− dianion form in [C6H9N2)2(C4O4)] (III). They crystallize in the triclinic and monoclinic crystal system with space group P−1, P21/c, and P21/c, respectively. Crystal structure analysis reveals that, far from forming discrete ionic species in (I) and (II), it is likely
that there is large degree of proton sharing between the two hydrogen squarate anions in (I) and between the neutral moieties
in (II), with the H atom lying almost symmetrically between the donor and acceptor sites, as evidenced by the long O–H and
N–H bonds and short H···O distances. Ab initio calculations have been carried out for three compounds by using DFT/B3LYP and
HF methods at 6-31++G(d,p) basis set. Although the supramolecular interactions have some influences on the molecular geometry
in solid state phase, calculated data show that the predicted geometries can reproduce the structural parameters. The results
of the optimized molecular structure for three compounds obtained on the basis of two models are presented and compared with
the experimental X-ray data. Calculated vibrational frequencies are consistent with each other and experimental IR data. The
theoretical electronic absorption spectra have been calculated by both TD–DFT and HF–CIS methods. Molecular orbital coefficients
analysis suggest that the electronic transitions are mainly assigned to n → π* and π → π* electronic transitions. 相似文献
82.
Anatoliy K. Prykarpatsky Nikolai N. BogoliubovJr. Jolanta Golenia Ufuk Taneri 《International Journal of Theoretical Physics》2008,47(11):2882-2897
Introductive backgrounds to a new mathematical physics discipline—Quantum Mathematics—are discussed and analyzed both from
historical and from analytical points of view. The magic properties of the second quantization method, invented by V. Fock
in 1932, are demonstrated, and an impressive application to the nonlinear dynamical systems theory is considered.
The Authors devote their article to their Friend and Teacher academician Prof. Anatoliy M. Samoilenko on occasion of his 70
years-Birthday with great compliments and gratitude to his brilliant talent and impressive impact to modern theory of nonlinear
dynamical systems of mathematical physics and nonlinear analysis 相似文献
83.
Yılmazoğlu Mesut Bayıroğlu Fatih Erdemi Hamit Abaci Ufuk Guney H. Yuksel 《Journal of Solid State Electrochemistry》2023,27(5):1143-1154
Journal of Solid State Electrochemistry - In this study, polymeric membranes composed of ionic liquid (IL), 1-ethyl-3-methylimidazolium tetrafluoroborate supported sulfonated poly(ether ether... 相似文献