mixed posed of polyvinyl alcohol (PVA) and polyvinylpyrrolidone (PVP) or PVA and soluble starch, respectively. The addition of glutaraldehyde may increase crosslinkage between PVA and starch chains or PVA molecules themselves. Then all of anics were removed by thermal treating in air atmosphere, the final products were obtained. The influence of mass ratio of ferrocene to polymers on the morphology and structure of the products were also investigated. The crystallinity, surface morphology, pore structure and ic properties of the products were characterized by using the X-ray diffractionmeter (XRD), high resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), BET analyzer and vibrating sample ometer (VSM). The results indicated that the purity and crystallinity of the product could be improved as the annealing time prolonged. Moreover, the morphology, size, pore structure and crystallinity of the products could be tuned by changing the amount and variety of the capping polymers. The ic multi-porous iron oxide particles with different morphology and micro/nano-structure were utilized for immobilization of ase. The results showed that the apparent activity of the immobilized ase increased as the pore volume increasing. In addition, the operational stability of the immobilized ase increased when the pore diameter decreased.
Key words : ic, multi-porous material, iron oxide, ase, immobilization
§ 引言
第一章绪论
随着材料科学的不断发展,人们对材料性能的要求也越来越高。高比表面积、
均一尺寸、以及具有磁特异性作为材料的重要性能受到人们的极大关注。为了提高材料的比表面积,一方面人们制备出具有多孔状[1]、网状[2]、刺球状等不同表面结构的材料,另一方面随着材料尺寸的减小,比表面积也会逐渐增大。当材料尺寸达到纳米级以后,人们开始关注如何对其进行高效分离。目前对微粒分离效率较高的手段主要包括高速离心分离和磁分离两种,其中,磁分离以其方便、快速和分离效率高等特点而受到人们极大的青睐。但是,使用磁分离的前提是材料具有一定的磁性,现今较常用的途径有以下两种,一种途径是制备出本身具有磁性的纳米材料,另一个途径是制备磁性复合材料,即使一些室温下为非磁性的材料与磁性材料复合,使整体具有磁性,从而用于磁分离。
§ 多孔材料概述
§ 多孔材料概念及研究意义
多孔材料因具有高的比表面积,孔径均一可调等优良特性而在环境能源、光电材料、生物医学等领域得到广泛应用[3] 。按国际纯粹与应用化学联合会
(IUPAC)的定义,多孔材料按孔径大小可分为三种,其中孔径小于 2 nm 的称为微孔材料(Microporous),孔径介于 2-50 nm 的称为介孔材料(Me
磁性多孔材料的制备及其固定化漆酶的应用分析 来自淘豆网m.daumloan.com转载请标明出处.
