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991.
Multireference calculations on low-lying states and the X~3 Π_u -~3 Π_g absorption spectra of indium dimers 下载免费PDF全文
Multireference configuration interaction calculations are carried out on 11 Λ-S low-lying electronic states of indium dimers. The states are investigated with spin-orbit pseudopotentials via the state-interacting method, and characterized by fitted spectroscopic constants based on computed potential energy curves. The vibrational structures of the double-potential well 0+g (I) ( 3 Σ g ) state are also analyzed. The experimentally observed absorption spectrum centred at ~ 13000cm-1 is simulated and assigned to X 3 Πu (v=0)-3Πg transition according to the present ab initio calculations on transition energies and dipole moment functions. 相似文献
992.
Electron-phonon coupling in cuprate and iron-based superconductors revealed by Raman scattering 下载免费PDF全文
Electron-phonon coupling (EPC) in cuprate and iron-based superconducting systems, as revealed by Raman scat- tering, is briefly reviewed. We introduce how to extract the coupling information through phonon lineshape. Then we discuss the strength of EPC in different high-temperature superconductor (HTSC) systems and possible factors affecting the strength. A comparative study between Raman phonon theories and experiments allows us to gain insight into some crucial electronic properties, especially superconductivity. Finally, we summarize and compare EPC in the two existing HTSC systems, and discuss what role it may play in the HTSC. 相似文献
993.
THERMODYNAMIC ANALYSIS AND FORMATION ENTHALPY CALCULATION OF OXYGEN VACANCY DEFECT IN DOPED LITHIUM NIOBATE CRYSTALS 下载免费PDF全文
Based on the thermodynamic analysis of oxygen vacancy defects in lithium niobate (LiNbO3 (LN)) and the data of thermogravimetric experiment, the formation enthalpies of congruent and several rare-earth (RE) doped LN crystals have been calculated. It was found that the formation enthalpy of oxygen vacancies can be decreased evidently by doping with valence-changeable RE ions. The experimental results were discussed and a new reduction process for photorefractive LN crystals at a relatively low temperature was proposed, and the reduction-treated crystals showed good effect in practical use. 相似文献
994.
由于锇胺分子氢配合物中有特殊的键M(η2 H2 )和特殊的配体 分子氢的存在 ,故而具有丰富的取代化学和特殊的光谱性质。在无机化学、配位化学、生物、医药等方面都有极为广阔的应用前景。本文就此进行了简要的回顾与展望 相似文献
995.
It is well-known that nano-systems can have properties which are distinctly different from macroscopic systems. In this study we point out the following specific behaviour: if the particle number is decreased so that the size of the system is in the nanometer-realm, new effects emerge which reflect certain features of biological systems although the system is inorganic in nature. This behaviour is shown by realistic molecular dynamics calculations in connection with aluminum-nanoclusters at various temperatures. The clusters can transform without external influence from a metastable into a stable state, and there can be more than one stable state, that is, we observe a bifurcation in the sense of chaos-theory. The stable states can differ in both the atomic structure and the outer shape. 相似文献
996.
Yanpei Luo Xin Zhou Jiangwei Zhang Yu Qi Zheng Li Fuxiang Zhang Can Li 《Journal of Energy Chemistry》2021,(12):385-390
The hybridization between the outmost s orbitals of metal (Bi3+,Sn2+,Pb2+,Ag+) and O 2p orbitals has been widely employed to develop innovative semiconductors w... 相似文献
997.
高效液相色谱法同时测定生物质乳酸发酵液中有机酸及糖类化合物 总被引:3,自引:0,他引:3
建立了高效液相色谱(HPLC)同时测定生物质乳酸发酵液中有机酸及糖类的分析方法。使用Bio-Rad Aminex HPX-87H色谱柱,以5 mmol/L的H2SO4为流动相,在柱温55 ℃,流速0.6 mL/min条件下,采用示差折光检测器进行检测。结果表明,该方法可在17 min内实现发酵液中各种有机酸和糖类化合物等的完全分离与定量,6种有机酸和3种糖类化合物在0.15~5.19 g/L范围内的线性关系良好,回归方程的线性相关系数在0.9998以上。将该法用于米根霉发酵液的检测,两个水平的加标回收率为96.91%~103.11%,相对标准偏差(n=6)为0.81%~4.61%。该法适用于微生物发酵液中多种有机酸和糖类的快速、高效分离和定量测定。 相似文献
998.
E. V. Agafonova Yu. V. Moshchenskii M. L. Tkachenko 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(6):1035-1037
The temperature and enthalpy of the melting of caffeine, which are 235.5 ± 0.1°C and 19.6 ± 0.2 kJ/mol, respectively, are determined by DSC. The melting entropy and the cryoscopic constant of caffeine are calculated. 相似文献
999.
A. M. Safiulina O. A. Sinegribova A. G. Matveeva E. I. Goryunov M. S. Grigoriev E. E. Nifant’ev I. G. Tananaev 《Russian Journal of Inorganic Chemistry》2012,57(1):108-114
The extraction capacities and selectivities of 1,8-naphthyridine-based neutral organophosphorus reagents in extracting trivalent lanthanides (Ln, Nd, Ho, Yb) from carbonate solutions were studied. The length and nature of the linker between the naphthyridine and phosphoryl moieties were found to have considerable influence on the efficiency and selectivity of lanthanide extraction. 相似文献
1000.
V. P. Chizhkov V. N. Boitsov 《Russian Journal of Physical Chemistry A, Focus on Chemistry》2012,86(2):298-302
The Gibbs energy increment during the distillation of a dilute solution in a separation cascade was calculated. An interpretation of the minimum work thermodynamically required during the symmetric separation of a binary mixture is suggested. 相似文献