液相OH•, NO3•和SO4•-与二甲基硫反应机理

利用激光闪光光解技术研究了液相二甲基硫(DMS)与OH^•, NO₃^•和SO₄^•-自由基的微观反应机理. 实验结果表明: 在pH 5～9时, OH^•氧化DMS生成DMSOH^•, DMSOH^•会与DMS反应生成(DMS)₂⁺; 而NO₃^•和SO₄^•-;会直接氧化DMS生成DMS^＋, 生成的DMS^＋会与DMS反应生成(DMS)₂⁺.(DMS)₂⁺与氧气的反应很慢, 它的衰减受pH影响较大.     

新型螺旋状一维超分子链配合物的晶体结构(英)

The crystal structure of quasi-one-dimensional compound Ni[S₂CPyrd]₂ (Pyrd=pyrrolidine) has been determined by X-ray diffraction technique. It crystallizes in the monoclinic system, space group P2₁/c, with lattice parameters a=0.631 6(1) nm, b=0.746 5(2) nm, c=1.576 5(4) nm, β=106.08(3)°, and Z=2. The nickel atom had a square-planar geometry. The most prominent feature in the crystal structure is that the bis(pyrrolidinedithiocarbamato) nickel(Ⅱ) forms a well-separated stacking column along the a-axis through supramolecular interaction, and they are uniformly spaced to give a helical one-dimensional chain structure. CCDC: 220648.     

一维链状超分子化合物[Zn(dafo)2(H2O)2](NO3)2(dafo=4,5-二氮芴-9-酮)的合成、表征和晶体结构

超分子化学是分子间弱相互作用和分子组装的化学,近年来超分子晶体日益受到重视,超分子化合物在材料,催化,药物等领域有广泛的应用前景[1,2]。4,5鄄二氮芴鄄9鄄酮(dafo)是一种多吡啶配体,它含有羰基,易衍生出各种桥联配体,该化合物及其衍生物有特殊的结构和性能[3~5]。Dafo具有     

各种金属参与的水相Barbier-Type反应

详细地概括了各种金属和金属盐参与的水相Barbier-Type反应,对反应机理以及反应的化学、区域和立体选择性进行了系统的总结,此外,还对水相Barbier-Type反应在有机合成中的应用作了初步的介绍.     

辐射接枝共聚合反应及其在有机生物医用材料制备中的应用

γ-射线辐射高分子材料表面接枝共聚合是一种绿色的、重要的有机生物材料合成制备方法. 综述了γ-射线辐射接枝共聚反应的原理、特点, 阐述了预辐射接枝共聚和共辐射接枝共聚的方法, 介绍了当前γ-射线辐射接枝共聚反应在改善有机生物医用材料的表面亲水性、生物相容性等方面的应用. 对辐射接枝共聚合制备功能药物载体研究进行了简要介绍.     

含联萘基团的旋光性聚喹啉的合成与性质

由2，2′－二甲氧基－1，1′－联萘 了旋光活性的2，2′－二甲氧基－6，6′－二乙酰基－1，1′－联萘(DMDABN），经元素分析，NRM，IR和MS等方法对其进行结构表征，DMDABN与3，3′-二苯甲酰基－4，4′二氨基－二苯基醚通过Friedlander反应合成了旋光性聚喹啉，所制备的聚喹啉具有较高的玻璃化转变温度（474－578K），热分解温度（703－770K），很好的耐溶性能和较强的旋光活性。     

流化床中高分散镍基催化剂上甲烷的自热重整和部分氧化

Highly dispersed Ni catalysts on spherical SiO2 were prepared by simple impregnation of Ni（acac）2, [Ni-（NH3）6-n（H2O）n]^2＋, [Ni（en）3]^2＋ and [Ni（EDTA）]^2-. Pulse adsorption of H2 and TEM analysis results confirmed that Ni was dispersed very well on the surface of SiO2 even after calcination （4 h） and reduction （1 h） at high temperature of 800 ℃. These highly dispersed and uniquely sized Ni crystallites were more stable and more reactive for both autothermal reforming and partial oxidation of methane in fluidized reactor.     

Influence of background pressure on the microstructure and optical properties of Mo/Si multilayers fabricated by magnetron sputtering

Mo/Si multilayers were fabricated by using magnetron sputtering method at different background pressures:6×10-5 Torr,3×10-5 Torr,and 3×10-6 Torr.The reflectivity of the Mo/Si multilayers increased from 1.93% to 16.63%,and the center wavelength revealed a blue shift to 0.12 nm with the decrease of background pressure.Grazing incident X-ray diffraction(GIXRD) indicated that multilayers fabricated at high background pressure possessed better periodic structure and thinner Mo-on-Si interlayers.Low crystallization degree in(110) preferred the orientation of Mo layers and serious interdiffusion in the Mo/Si multilayers fabricated at low background pressure were observed by transmission electron microscopy(TEM).According to quantitative analysis of microstructural parameters,the Mo layers thickness and thickness ratio of Mo/Si multilayers both decreased and approached the design value gradually by the decrease of background pressure.In addition,the thicknesses of Mo-on-Si and Si-on-Mo interlayers were 1.17 nm and 0.85 nm respectively.It is suggested that the influence of background pressures on the microstructure has a critical role in determining the optical properties of Mo/Si multilayers.     

Relation between the E(5) symmetry and the interacting boson model beyond the mean-field approximation

In a unified algebraic scheme,we investigate the relation between the E(5) symmetry and the interacting boson model beyond the mean-field level.The results indicate that the E(5) symmetry is actually in between the critical point of the U(5)-O(6) transition and the O(6) limit but it is fairly close to the former based on the phase diagram of the interacting boson model at the large boson number limit.In addition,an algebraic Hamiltonian of the E(5)-β2n model is proposed.