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101.
本文采用Hartree-Fock自洽场方法,从理论上计算了铜到钼的类钠离子1s~22s~22p~6nl(n=3~6,l=O~5)各能级能量。给出了有可能实现软X射线激光的跃迁(5g—4f,5f—4d,6g—4f,6f—4d)的光谱性质:跃迁波长、振子强度,并和实验值进行了比较,跃迁波长的相对误差不超过千分之二。从计算结果可知,Se的6f—4d跃迁,Br的6g—4f跃迁,Zr的5f—4l跃迁,Nb的5g—4f跃迁都已进入水窗波段。 相似文献
102.
Both the spectra and infrared transition strengths of C6H6 and C6D6 for the C? H stretching overtones up to as high as v = 10 are described in high precision with few parameters (six for the spectra and four for the transition strengths) by the Iachello–Oss algebraic model. The Hamiltonian model is solved in the symmetry adapted bases, which are constructed by the symmetrized boson representation (SBR) technique. The results show that the combination of the algebraic method and SBR technique is a powerful method for describing vibrations of large molecules and high overtones. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 相似文献
103.
104.
Zhifang Xi Wei Bie Wei Chen Dong Liu Leen van Ofwegen Peter Proksch Wenhan Lin 《Helvetica chimica acta》2013,96(12):2218-2227
Six new biscembranoids, namely, sarcophytolides G–L ( 1 – 6 , resp.), together with six known analogs, were isolated from a marine soft coral Sarcophyton elegans. The structures of the new compounds were established on the basis of 1D‐ and 2D‐NMR (COSY, HSQC, HMBC, and NOESY) spectroscopic analysis together with the aid of MS, CD, and IR data. The unusual isobiscembranoid sarcophytolide G ( 1 ) was found for the first time in the genus Sarcophyton. 相似文献
105.
This article discussed "teaching-practice-test" teaching mode with teaching practical experience and content matching.Results showed that this mode highlighted the proportion of practice and problem-solving in the process of learning; improved students' ability to solve problems using professional and disciplinary knowledge; changed learning styles from cramming way to autonomous learning step by step and trained students' creativity. 相似文献
106.
In this study, a guided mode resonance filter with the improved structure for facile fabrication is designed; the properties of the designed filters are simulated by rigorous coupled wave analysis. It is found that the resonance wavelength and spectral linewidth are slightly increased with the increasing of the grating thickness, and seldom changed with the thickness of the grating filling factor, as the parameter error of the grating thickness and the grating filling factor are deviated from the designed value by ±10%, respectively, which are very favorable for simplifying preparation process of the GMR filter. 相似文献
107.
Zhongyuan Huang Renguo Lu Ting Huang Hongyan Wang Tongsheng Li 《Journal of Macromolecular Science: Physics》2013,52(7):937-949
Crosslinked fluorinated polyimides (CFPI) were successfully synthesized to study and explore the effect of cross-linkage on the migration of fluorinated segments and on the adhesion strength. Characterization by dynamic thermomechanical analysis (DMA) and thermo gravimetric analysis (TGA) confirmed good thermal properties of CFPI. X-ray photoelectron spectroscopy (XPS) results showed that the ratio of fluorinated component (6FDA-ODA) concentration of the surface to the bulk decreased with the crosslink density. The water contact angle of CFPI was lower than that of non-crosslinked fluorinated polyimide, indicating that the migration of fluorinated groups to the surface was reduced by the presence of cross-linkage. Therefore, CFPI, with no fluorine segregation on the surface, exhibited excellent wetting of adherent surfaces and adhesion strength, which was proved by lap shear strength (LSS) measurements and scanning electron microscopy. 相似文献
108.
《Journal of Coordination Chemistry》2012,65(18):2005-2014
The novel heteronuclear complexes [Na2Zn(dipic)2(H2O)] n (1) and [Na2Mn(dipic)2(H2O)2] n (2) (H2dipic?=?pyridine-2,6-dicarboxylic acid) were synthesized and characterized by single-crystal X-ray diffraction, analysis, IR spectroscopy and thermogravimetric analysis. Complex 1 consists of infinite 2D double layers, which are further attached into a 3D network through π–π stacking. All sodium ions are 3-coordinate. Complex 2 has an intricate 3D structure, in which two sodium ions are differently involved in forming polymeric coordination units, and are 3- and 7-coordinate, respectively. Dipic anions act as multidentate ligands showing novel and unprecedented bridging coordination modes. One ligand coordinates to three metal ions and with five bonds; the other coordinates five metal ions with nine bonds. 相似文献
109.
110.
Zourab Brodzeli Andrew Michie Qi Guo Evgeny P. Pozhidaev Vladimir Chigrinov 《Liquid crystals》2013,40(10):1427-1435
We present a detailed theoretical and experimental study of the reflectance response of a deformed-helix ferroelectric (DHF) liquid crystal (LC) cell to an applied voltage under cross-polarisers. Using a model based on the effective dielectric tensor approximation, we derive simple analytical formulas to design a LC cell with maximum modulation depth and optimal linearity of the electro-optical response intensity versus the electric field. Our experimental results show that the cell works at frequencies up to 10 kHz and exhibits excellent linearity, with a total harmonic distortion as low as ?70 dB. These findings suggest that DHF-LCs can be exploited to develop simple and accurate optical sensors. 相似文献