表面键联型TiO2/SiO2固定化催化剂的结构及催化性能

 采用浸渍法制备了表面键联型TiO2／SiO2固定化光催化剂．XRD\r\n,FT－IR,XPS和BET比表面积测定结果表明,TiO2通过Ti－O－Si联结\r\n负载于多孔硅胶的表面,由此提出TiO2／SiO2的结构模型．考察了多孔\r\n硅胶的粒度及氧化钛负载量对催化剂活性的影响．对活性艳红K－2G（\r\nR15）的光催化脱色反应,最佳的光催化剂30％TiO2／SiO2（Ims30）比\r\nB－TiO2粉末的催化速率快3倍．随着载体粒度的减小,催化剂的比表面\r\n积增大,催化活性升高;多孔硅胶不仅起着支持体的作用,而且具有分\r\n散的作用;多孔硅胶具有很好的透光性．经ξ－电位测定,所制备催化\r\n剂的等电点为3．0pH单位,表明催化剂表面呈酸性．     

两个由铜离子与Waugh-型阴离子构筑的化合物的合成、晶体结构及表征

通过水热合成得到了一个新颖的包含四核铜配合物的无机-有机杂化化合物[CuCl(H₂O)₄)][CuCl(H₂O)(Phen)][{(CuPhen)₂Cl₂}₂(bdc)]₂[P₂W₁₈O₆₂]·5H₂O(1)(Phen=1,10-phenanthroline和bdc=1,4-benzenedicarboxylate),对其进行了元素分析、红外光谱、热重、电化学等表征,并用X-射线单晶衍射测定了它的晶体结构。化合物1含有由Cl和bdc桥连的四核铜配合物阳离子[{(CuPhen)₂Cl₂}₂(bdc)]²⁺。此外,化合物1的电化学研究表明其对亚硝酸的还原具有很好的电催化活性。     

A Review of Surface Functionalized Amine Terminated Dendrimers for Application in Biological and Molecular Sensing

Dendrimers are three dimensional nanosized synthetic molecules that have internal cavities and numerous surface groups. In recent times they have received increased attention in sensing applications. For dendrimers to be used as sensors, they most commonly require functionalization at their surface. This is because the surface is generally the first point of contact between the dendrimer and the outside world, hence surface functionalization serves to selectively home in on the target analyte. Further, sensor signals may be transmitted through surface functionalities e.g. fluorochromic molecules. It is therefore important to document surface functionalization approaches. Dendrimers with amine surface groups have the advantage of being able to be conjugated to other molecules via an amide linkage, which is one of the most fundamental and widespread chemical bonds in nature. In this paper we demonstrate the properties of dendrimers that make them so applicable to sensing. We review several methods for functionalizing dendrimers via an amide linkage, as well as present a review of surface functionalized polyamidoamine, polyamine, and polypeptide dendrimers that have been employed for biological, chemical and molecular sensing.     

某些新的含醛基和二氰基乙烯的偶氮染料的合成和可见光谱

红外染料可用于光学记录和光学数据储存,因此它是近年来发展的高技术领域之一。但是目前能应用的红外染料非常少,且绝大部份是菁染料。最近有人报道了醌型和偶氮型红外染料的合成。所谓红外染料是指λ_(man)在700nm以上的分子,含一个发色团体系往往是不够的。因此研究各类助色团和发色     

芳酰基芳基偶氮化合物的合成

芳酰基芳基偶氮化合物的合成;芳酰基芳基偶氮化合物;哌啶氮氧自由基;芳酰基芳肼;相转移催化     

测定粮食、水果、蔬菜稀土总量的

以一定比例的镧、铈、镨、钕、钐的氧化物配制的混合标准溶液在酸性条件下与二溴羧基偶氮胂反应,632nm处的吸光光度在0－1．5mg/L范围内符合比耳珲律,检出限为1．5μg/L,相关系数为0．9995。方法不需加掩蔽剂。试样实测结果的相对标准偏差＜7％（n＝5）,加标回收率在84％－108％之间。     

Effect of dipping solution pH values on electrostatic layer-by-layer self-assembly of side-chain azo polyelectrolyte

The effect of pH value on the electrostatic layer-by-layer self-assembly and the photo-responsive behavior of Poly{2-[4-(4-ethoxyphenylazo)phenoxy]ethyl acrylate-co-acrylic acid} (PEAPE) was studied. Results show that in the studied pH value range, the lower the pH value is, the higher is the UV-vis absorbance and the larger is the thickness of the multilayer films. FTIR studies indicate that the azo polyelectrolyte exhibits a different ionization degree in solutions with different pH values. The higher absorbance and the larger thickness of the layer-by-layer films can be attributed to the low ionization degree and the shrinkage conformation of PEAPE in the solution with low pH values. FTIR analysis also confirms that the driving force for layer-by-layer self-assembly of PEAPE and PDAC is the electrostatic interaction. __________ Translated from Acta Polymerica Sinica, 2007, 5: 440–445 [译自: 高 分子学报]     

偶氮材料——乙基橙的光致双折射特性

将偶氮化合物乙基橙样品置于一对正交的偏振片之间，用一束激发光照射该样品，分别测量 在激发光的不同强度和不同偏振方向下探测光的透射功率，研究样品的双折射特性.实验表 明，透射光的饱和值和稳定值与激发光强成正比，且与激发光偏振方向有关，探测光与激发 光振动方向的夹角(θ)为45°时，其值最大；若θ不太小（>10°），sin²2θ 与透射光的饱和值、稳定值成线性关系.同时，利用巴俾涅补偿器对样品的双折射率差进 行了测量，分别得到了绿光激发前后的准确数值为1.11×10^-3和3.57×10 ^-3. 关键词： 偶氮 双折射 测量     

Supramolecular organic frameworks derived from bromoaryl-substituted dichlorodiazabutadienes via Cl···Br halogen bonding

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