Adsorption of metal halides from ethanol solutions by a 3-n-propylpyridiniumsilsesquioxane chloride-coated silica gel surface

3-n-propylpyridiniumsilsesquioxane chloride polymer, abbreviated as SiPy+Cl-, was used to coat a porous silica gel, SiO2, surface to form the chemically modified solid SiO2/SiPy+Cl-. The resulting polymer film was well adhered to the surface and presented an ion exchange capacity of 0.74 mmol g(-1). Metal halides, MClz [M=Fe(III), Cu(II), and Zn(II)], were adsorbed by the modified solid from ethanol solutions as neutral species by forming the surface anionic complexes described by the equation: mSiO2/SiPy+Cl-+ MClz <=> (SiO2/SiPy+)m[MCl(z+m)]m-, where the [MCl(z+m)]m- species adsorbed on the surface are FeCl4-, ZnCl4(2-), and CuCl4(2-). Accurate estimates of the specific sorption capacities and the heterogeneous stability constants of the immobilized metal complexes were determined with the aid of computational procedures.     

β沸石分子筛固体酸的制备及其在异丁烷和丁烯烷基化反应中的应用

以四乙基溴化铵(TEABr)为模板剂，硅胶为硅源，铝酸钠为铝源，采用水热晶化法合成β沸石．研究了其晶化温度、晶化时间、硅铝比、碱度、水含量等各种因素对晶化过程和产物性质的影响．得出适宜的初始凝胶组成为SiO2和Al2O3的比值在25-60之间，TEABr和SiO2的比值在0．32～0．4之间，OH^-和SiO2的比值在0．2～0．23之间，H2O和SiO2的比值在8．6～18．0之间．通过XRD，ICP，IR，SEM和NH3-TPD方法分别对样品的结构和性质进行了表征．烷基化反应的结果表明，β分子筛具有较为适宜的孔结构和反应活性．     

Detection of Tumor Necrosis Factor Gene by Piezoelectric Nucleic Acid Senosr

A piezoelectric nucleic acid sensor was constructed ofr detection of tumor necrosis factor gene.Two methods were employed for immobilization of nucleic acid probe on gold electrode of piezoelectric crystal.The results show that polyethyleneimine adbesion and glutaraldehyde cross-linking method has higher sensitivity,stability and selectivity than protein A method.The solid-phase nucleic acid hybridization of oligo unclecotides and tumor necrosis factor target gene sequence were monitorde using this sensor.Tumor necrosis factor gene sequence(580bp) was detected by this nucleic acid sensor for the first time.     

熔融织构生长强磁浮YBCO超导块材的取向和结构

采用熔融织构生长法结合顶部Ｓｍ１２３籽晶技术，成功地制备了直径为２０ｍｍ的ＹＢＣＯ超导块材。该块材具有极强的磁性能。用Ｘ射线θ／２θ扫描和Φ扫描分析其结构表明，样品在三维方向上具有很强的择优取向，其ｃ、ａ、ｂ轴方向分别与Ｓｍ１２３籽晶的ｃ、ａ、ｂ轴方向一致，并具有类似单晶的结构特点。     

联苯甲酰双缩氨基脲硫氰酸根硝酸根混合阴离子配位钕(Ⅲ)配合物的合成与结构

合成了联苯甲酰双缩氨基脲硫氰酸根、硝酸根混合配位的钕(Ⅲ)配合物。在此配合物中只有1个链状配体,另有2个硫氰酸根、1个硝酸根和1个水分子参与配位。总配位数是9。晶体结构分析表明,该配合物晶体属三斜晶系,P空间群。晶胞参数a=10。866(2),b=13.687(3),c=15.433(3),α=98.75(4)°,β=107.64(5)°,γ=112.14(5)°。最终偏差因子R=0.075。用INDO方法计算结果表明:NCS对Nd(Ⅲ)的配位比=C基对Nd(Ⅲ)的配位强。     

New Approaches to Coupling TLC with TOF-SIMS

JPC – Journal of Planar Chromatography – Modern TLC - A new hyphenated technique that enables coupling of thin-layer chromatography (TLC) with time-of-flight secondary-ion mass...     

纳米级MoO3微粉的制备与性质

以(NH4)6Mo7O24·4H2O和HAc为原料,制备了纳米级MoO3微粉,用电镜观察其形貌和粒径的大小,并进行X射线衍射分析.在制备过程中,通过严格控制溶液的浓度、酸度等条件,首先得到纤维状的酸式仲钼酸铵(NH4)4H2Mo7O24·4H2O和 (NH4)3H3Mo7O24·4H2O.并通过加热使其分解,从而获得纳米级MoO3微粉.     

Shape-controlled synthesis of copper colloids with a simple chemical route

The new electrical and optical properties of nanomaterials depend sensitively on both size and shape, which are of both fundamental and technological interest. This paper introduces a simple chemical method to produce copper particles, which has the ability to shape the particle without using any capping agent or template. In our synthetic procedure, the reactant concentration and temperature exerted a strong influence on the shape of the copper particles. At low reactant concentrations, the particles were cubic; at high reactant concentrations, obtained particles were spherical. The number of hollow particles greatly increased when the synthesis was performed at low temperature. We also synthesized a copper cubic ring at lower temperature, and it has been rarely reported. The absorption spectrum of hollow particles showed obvious red shifts, which suggests the possible assembly of novel optical materials.     

A time dependent density functional theory study of alpha-84 phycocyanobilin chromophore in C-phycocyanin

The optical characteristics of absorption and circular dichroism (CD) spectroscopy of an alpha-subunit of C-phycocyanin (C-PC) were investigated by using time dependent density functional theory (TDDFT) combined with the polarizable continuum model (PCM). When the protonation of alpha-84 phycocyanobilin (PCB) and its interaction with the protein moiety in C-PC have been taken into account, satisfactory assignment of the absorption and CD spectra of alpha-84 PCB can be achieved. The TDDFT-PCM calculations conclude that in the visible absorption region the main peak arises from the pi electron excitation of the pyrrole rings and the shoulder peak comes from the charge transfer from Asp87 (a nearby amino acid residue) to PCBH(+).