铁基超细粒子催化剂结构与还原行为的Mssbauer谱研究

铁基超细粒子催化剂具有优良的F-T反应性能。本工作利用原位Mssbauer谱辅以XRD技术研究了含有钾助剂的F-T合成铁基超细粒子催化剂的结构与还原行为,考察了催化剂组成和第二金属组分(Mn,Zn,Mg)的影响。“纯”铁超细粒子催化剂在氢气中很容易经Fe_3O_4还原为零价铁。第二金属组分的引入,一方面阻碍了催化剂的还原,另一方面稳定了Fe~(2+)的存在而使其成为还原的主要中间相,这有利于反应条件下形成类尖晶石结构的活性相。对于Fe-Mn催化剂,上述效应随锰含量的增加而更趋显著。铁基超细粒子催化剂在氢气中的还原能力依“纯”Fe>Fe-Zn>Fe-Mn>Fe-Mg的顺序递减,这在一定程度上反映了铁与第二金属组分之间相互作用的强弱。     

草酸锰分解过程的机理函数判别和动力学研究

用等温热重和线性升温热重分析法研究了草酸锰热分解过程,提出了判断其机理函数的3步判别法。经实验和理论分析证明,该反应受随机成核和晶核随后生长的过程(A_3a机理)支配,其活化能E=103.95 kJ/mol,频率因子A=4.448×10~8min~(-1).动力学补偿效应为IgA=0.09661E-1.2856     

毛蕊杜鹃挥发油化学成分研究

毛蕊杜鹃(Rhododendron tubulosum Ching ex wang wei-yei)系杜鹃花科杜鹃花属植物,分布于四川、西藏、甘肃和青海,其中青海分布最广,藏民常作为单方草药用于治疗肺炎和老年慢性气管炎,具有镇咳、祛痰作用,本文用自制的同时水汽蒸馏-溶剂萃取装置,从采自青海玉树州的毛蕊杜鹃鲜叶和嫩枝提取挥发油,用毛细管气相色谱-质谱和Kovats指数双重定性法对     

Deposition of Layer－by－layer Inorganic－organic Nano－hybrid Ultrathin Films onto SBA－15

Deposition of inorganic-organic nano-hybrid ultrathin films onto mesoporous silicate materials has been proven possible by using layer-by-layer assembly method. In combination with sol-gel method, titania, subsequently dye molecules (or polymer) were successfully fabricated onto the inner wall of SBA-15. Their structures were preliminarily characterized by FTIR and solid-state UV-Vis spectroscopy, thermal analysis, and BET surface area measurements,respectively.     

Synthesis of monodisperse poly(chloromethylstyrene-co-divinylbenzene) beads and their application in separation of biopolymers

The monodisperse, porous poly(chloromethylstyrene-co-divinylbenzene) beads of 7.9 microm were prepared by a single-step swelling and polymerization method. The seed particles prepared by dispersion polymerization exhibited good absorption of the monomer phase. Based on this media, a weak cation-exchange (WCX) stationary phase for HPLC was synthesized by a new chemically modified method. The prepared resin has advantages of biopolymer separation, high column efficiency, low column backpressure, high protein mass recovery, and good resolution for proteins. The dynamic protein-loading capacity of the synthesized WCX packings was 18.2 mg/g. Five proteins were separated in 3.0 min using the synthesized WCX stationary phase. The experimental results show that the obtained WCX resin has very weak hydrophobicity. The WCX resin was also used for the rapid separation and purification of lysozyme from egg white in 5.0 min with only one step. The purity and specific bioactivity of the purified lysozyme were found to be more than 93% and 70 245 U/mg, respectively.     

DNA intercalating studies of [Ru(bpy)<Subscript>2</Subscript>HPIP]<Superscript>2+</Superscript> with intramolecular hydrogen bond ligand based on introduction of copper ion

The effects of copper ion on the interaction of [Ru(bpy)₂HPIP]²⁺(bpy = 2,2′-bipyridine, HPIP = 2-(2-hydroxyphenyl) imidazo [4,5-f] [1, 10] phenanthroline) with DNA have been investigated by electronic absorption spectroscopy and fluorescence spectroscopy. HPIP ligand of the complex with an intramolecular hydrogen bond can bind Cu²⁺ in the absence of DNA, as revealed by the absorbance and fluorescence decrease for [Ru(bpy)₂HPIP]²⁺. The resultant heterometallic complex binds to DNA via intercalation of HPIP into the DNA base pairs and its DNA-binding ability is stronger than [Ru(bpy)₂HPIP]²⁺ itself. The DNA bound [Ru(bpy)₂HPIP]²⁺ cannot bind Cu²⁺ at low Cu²⁺ concentration and the intramolecular hydrogen bond in HPIP is located inside the DNA helix. While the Cu²⁺ concentration is relative high, Cu²⁺ can quench the fluorescence of DNA bound [Ru(bpy)₂HPIP]²⁺. The quenching reason is proposed.     

西安地区成年健康人群血清中微量元素正常值研究

用随机抽样的方法对西安地区436名健康人血清中Zn、Fe、Cu、Mn、Pb、Cd、Cr、Ni、Mo和Se十种微量元素正常值进行石墨炉原子吸收光谱法测定，并用ST286型计算机进行多因素相关分析和统计处理．结果表明，血清Zn、Cu分布比较集中，其它元素变异度比较大；多数元素与年龄呈相关关系。其中Zn、Cu、Fe、Mn、Pb、Se与年龄呈正相关 而Mo则与年龄呈负相关；多数元素含量与地城环境中徽量元素的分布有明显的相似性．总之，不同地区不同性别和不同年龄段血清微量元素有显著的差异．