Theoretical calculation of electronic circular dichroism of the rotationally restricted 3,8'-biflavonoid morelloflavone

Theoretical calculation of electronic circular dichroism (ECD) of the rotationally restricted 3,8'-biflavonoid (+)-morelloflavone using time dependent density functional theory (TDDFT), performed at 298 K at B3LYP-SCRF/6-31G*//B3LYP/6-31G* level with COSMO model, permitted unequivocal assignment of its 2R,3S absolute configuration. The experimentally observed Cotton effect (CE) around 290 nm is contributed by the acetophenone pi --> pi* transition of the ABC-flavanone moiety and the electronic transition within the DEF-flavone moiety, while another diagnostic positive CE around 350 nm is attributable to the electronic interaction between the ABC-flavanone moiety and the DEF-flavone moiety, as well as the electronic transition within the DEF-flavone moiety. The remarkable differences of the calculated ECD of its two rotamers indicate that the rotational restrictions significantly affect the ECD of 3,8'-biflavonoids. Empirical ECD rules derived from monomeric flavonoids may not be applicable to configurational assignment of complex 3,8'-biflavonoids. This study has provided new insights in interpreting the experimentally observed ECD spectra of this class of compounds.     

14N16O2ν3带中红外激光磁共振超精细结构谱

报道了14N16O2ν3带(001-000)的5组新的超高分辨激光磁共振谱线的观测,包括实验的背景、装置、方法和结果.由于利用了内腔饱和吸收情况下的兰姆凹陷和最优化的相敏调制探测技术,所得光谱的分辨率达到了微波谱量级.这些谱线是分析14N16O2乃至非对称陀螺自由基分子的塞曼效应和超精细结构特性的重要实验资料.     

NO(X2Π1/2,3/2)υ=1←0塞曼跃迁谱及其特性研究

根据塞曼效应理论和激光磁共振光谱技术(LMR)的基本原理,讨论了双原子分子2П态的塞曼效应特性并导出了解释分子塞曼跃迁的简明代数拟合方程,用这些方程对14N16O(X2Π1/2,3/2)及15N16O(X2Π3/2) (υ=1←0)的LMR谱线进行数据拟合,得到塞曼跃迁上、下子能级的gJ因子值和二级塞曼效应因子k2.将按Hund耦合情形(a)及过渡情形(ab)的理论和拟合方程计算出的磁场位置分别与实验结果相比较,结果表明对NO分子而言,过渡情形(ab)能较真实反映它的耦合情况,且在较高强度磁场下,必须计及二级塞曼修正.验证了采用上述代数拟合方程实现新分子LMR谱线标识和指认的可靠性,并提供了系统的处理方法.     

Spectroscopic analysis of asymmetric top free radicals

Several key problems involved in the analyses of spectra of asymmetric top molecules, i.e., the effective Hamiltonian, the representation and basis vector, identification of energy levels, the selection rules, the relative intensity, and Zeeman tuning rate, were elucidated systematically. Introducing the high-order centrifugal distortion terms into the effective Hamiltonian, the precision for calculation has been improved substantially, which allows us to analyze the high-lying rotational transitions. A global analysis of all available spectra of¹⁴N¹⁶O₂ in the ground vibronic state has been made to obtain a set of molecular constants of¹⁴N¹⁶O₂ in the ground vibronic state which is the most precise and extensive so far. Using the improved parameters, some FIR LMR lines left unassigned hitherto have been identified successfully.     

富勒烯[60]的光化学反应研究

从光物理出发,综述了近几年富勒烯「６０」的光化学反应研究进展。Ｃ６０能发生诸多的光化学反应：（１）光氧化;（２）光氢化还原;（３）「２＋２」光环化加成;（４）与叔胺的光加成;（５）与氨基酸的光加成;（６）与金属有机化合物的光加成。     

CF X^2П（ν=1）远红外及NO X^2П（ν←0）中红外激光磁共振光谱的标识

根据塞曼效应理论和浙江磁共振（LMR）光谱原理,本文建立一了套用于标识激光磁共振光谱的模型方法,并成功地对CF X^2П（ν=1）远红外及NO X^2П（ν←0）中红外激光磁共振光谱进行了标识。为新自由基分子的激光磁共振光谱提供了快速而准确的方法。     

姜科植物化学成分的色谱／质谱研究

本文研究了姜科植物１１个样品，提取了挥发油，用色谱／质谱技术从挥发油中鉴定出１００多种成分。其中α－蒎烯，β－蒎烯，莰烯１，８－桉油素，β－水芹烯，柠檬酸，柠檬醛，香叶醇，丁子香酚，芳樟醇，α－姜烯，β－姜烯，α－姜黄烯，β－姜黄烯，石竹烯，姜酮，β－荜澄茄烯，香芹酮，乙酸香叶酯，乙酸芳樟酯等２０种化合物是多数姜科植物挥发油的共同成分。     

Fabrication of PZT/CuO composite films and their photovoltaic properties

In this paper, we reported the design and preparation of a double-layer antireflective (AR) coating, which possessed relatively high transmittance at 351, 527, and 1053?nm. The refractive indices and film thicknesses of the under layer and upper layer of the simulated AR coating were determined as 1.27, 95?nm and 1.18, 106?nm, respectively. The under layer of the double-layer coating dip-coated from a mixture of base-catalyzed and acid-catalyzed silica sols had a refractive index of 1.27. The upper layer fabricated by the deposition of methylated silica nanoparticles by simply adding methyltriethoxysilane into the base-catalyzed silica sols possessed a refractive index of 1.18. The hydrophobicity of coatings could be dramatically improved with the water contact angle increasing from 23.4° to 150.0°, and the refractive indices of the pure base-catalyzed silica coatings were easily decreased from 1.20 to 1.12 through the surface treatment of silica nanoparticles. Thus, we have successfully prepared a double-layer AR coating, which had a high transmittance of 99.8%, 96.1%, and 99.7% at 351, 527, and 1053?nm, respectively.

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软产道血肿的观察和护理体会

为探讨软产道血肿发生的原因,预防和减少阴道分娩的并发症,对12例软产道血肿发生的情况及相关因素进行了分析。结果表明,软产道血肿的形成与有无妊娠合并症、产程长短、助产技术密切相关。提示做好围产期保健工作,提高助产技术,加强产后的观察与护理,是防止软产道血肿的关键。