Solvent and pH Effects on the Electronic Spectra of Some Azo Benzimidazoles

The spectral behaviour of some new azobenzimidazoles in pure and mixed organic solvents and buffer solutions of varying pH have been studied. The observed bands are assigned to the possible electronic transition. The shoulder appearing in the visible region in the spectra of P‐NO₂ derivatives is ascribed to the existence of these compounds in azo‐hydrazone tautomeric equilibrium. The possibility of the formation of an intermolecular H‐bonded solvated complex between the molecules of p‐NO₂ derivatives and the proton acceptor solvents DMSO and DMF were studied. The pK values of these compounds were determined and explained on the basis of the relative contribution of acidic and basic character of respective species.     

降冰片二烯衍生物光敏异构化反应的机理研究

利用甲基卡唑为光敏剂，实现了三个降冰片二烯衍生物的光诱导介键异构化反应，荧光猝灭，化学诱导动态核极化（ＣＩＤＮＰ）以及热力学讨论都支持电子转移敏化机理，有关量子效率的计算表明单重态电子转移机制对光异构化反应的贡献远大于三重态能传递机制，此外还探讨了光异构化反应中的溶剂极性效应。     

动力极谱法测定海水中痕量锰

本文研究了孔雀绿极谐波性能,确定在醋酸-醋酸钠(pH=4.2)介质中,在示波极谱仪上可得到良好的极谱波。峰电位为-0.67伏(S.C.E)。用极谱法研究锰催化高碘酸钾氧化孔雀绿反应的机理。介绍了不需分离而直接测定海水中痕量锰的方法。其灵敏度可达0.2μg/l,对含10.1/μg锰的海水样进行11次平行测定,相对标准偏差为4.1%。本法亦适合自来水、河水中锰的分析。     

Synthesis and Mossbauer Spectra Studies of Mono-Binuclear Iron(III) Complexes with a Quinquedentate Ligand Derived from Saucylaldehyeds and Diethylenetriamine

Mono- and bi-nuclear iron(III) complexes of general formula [FeXL] and [LFe-Y-FeL](Bph₄)₂ have been prepared, and their spin state of iron atom in the complexes has been studied by means of the temperature dependence of the Mössbauer spectra, electronic spectra and magnetic measurement, where X is a mono- dentate ligand such as Cl-, NCS-, NCO-, N3-, pyridine and L denotes a quinquedentate Schiff base derived from salicylaldehyde and diethylenetriamine, and Y denotes bridged ligand such as pyrazine(pyr), 4,4′-bipyridine(bpy) and 4,4′-vinylenebipyridine(vibpy). On the basis of the Mössbauer and magnetic data, it was concluded that these complexes were all the high-spin (S = 5/2) slate. The effect of gamma ray irradiation for these complexes has been discussed.     

Cocrystallization of Two Different Pseudorotamers of Monocyclic Phosphorane Bearing Two Martin Ligands

Solution and crystal structures of monocyclic pentacoordinate phosphoranes bearing two Martin ligands and two carbon substituents are described. When the two carbon substituents are different, relative apicophilicity of the two monodentate carbon substituents could be determined based on the equilibrium ratio of the pseudorotamers. In some cases, x-ray structural analysis could be carried out and the crystallized structure from CH 3 CN is consistent with the major pseudorotamer in solution (CD 3 CN). Furthermore, when the equilibrium ratio of pseudorotamers is almost unity, novel cocrystallization of two pseudorotamers in a single crystal was observed.     

ON THE PHYSICAL PROCESS OF POLYMER CRYSTALLIZATION

Polymer crystallization is a process that connects the initial amorphous state and the final semicrystalline state. It is important to take due consideration of the initial state before crystallization, which determines the path of the crystallization process. New physical ideas are presented in regard to the processes of polymer crystallization from a dilute solution, from a melt or rubbery state, and from an oriented state, all based on experimental facts available with detailed discussions.     

Reactivity of Functionalized Phosphonates 1. Acid-Base Properties and Reactivity of Methyl Esters of Alpha-Aminophosphonic Acids

Acid-base properties and reactivity of series of alpha-aminophosphonates has been investigated. The reaction of addition of the aminophosphonates to phenylisocyanate was used as a model reaction. The influence of steric and electronic effects of substituents at alpha-carbon or nitrogen in amino group on the mechanism inversion from AdN to AdE is discussed.     

星系哈勃红移的非多普勒效应解释

分析了多普勒效应在解释星系哈勃红移现象时,星系际光传播过程存在的能量不守恒和宇宙膨胀时空不平权两大问题;提出了＂时空物质属性＂的3个基本假设;最后阐述了星系哈勃红移的非多普勒效应解释。     

Layer-Resolved Magneto-Optical Kerr Effect In Semi-Infinite Inhomogeneous Layered Systems

The contour integration technique applied to calculate the optical conductivity tensor at finite temperatures in the case of inhomogeneous surface layered systems within the framework of the spin-polarized relativistic screened Korringa-Kohn-Rostoker band structure method is extended to arbitrary polarizations of the electric field. It is shown that besides the inter-band contribution, the contour integration technique also accounts for the intra-band contribution. Introducing a layer-resolved complex Kerr angle, the importance of the first, non-magnetic buffer layer below the ferromagnetic surface on the magneto-optical Kerr effect in the Co | Pt m multilayer system is shown. Increasing the thickness of the buffer Pt, the layer-resolved complex Kerr angles follow a linear dependence with respect to m only after nine Pt mono-layers.