Preparation and Characterization of Starch-g-PVA/Nano-hydroxyapatite Complex Hydrogel

1Introduction Biodegradablehydrogelshadattractedmuchattentioninrecentyearsduetotheiruniquecombinationofproper ties,suchasbiocompatibility,permeability,hydrophilici ty,andlowcoefficientoffriction[1].Poly(vinylalcohol)(PVA)waswater solubleanddegradable[2].I…     

PAM、PNaA和P(AM-NaA)水凝胶微观形态的分形研究

用辐射聚合方法合成的丙烯酰胺、丙烯酸钠的均聚物及其共聚物水凝胶，借助于扫描电子显微镜技术观察了组成不同的干态水凝胶聚合物的微观形态特征，探讨了不均匀的微观交联网络的分形特性，用分形维数对水凝胶聚合物的微观网络的致密程度进行了量化表征。结果表明，分形维数能够从整体上定量地表征水凝胶聚合物的不均匀微观网络之间随组成改变而产生的细微差异，而且，样品的微观网络愈致密则其分形维数值愈大。     

高扭曲向列液晶显示器件的特性研究

本文研究了高扭曲向列液晶显示器件（ＨＴＮＬＣＤ）（扭曲角９０～１８０°），此器件与扭曲向列液晶显示器件（ＴＮＬＣＤ）相比较，能够增加液晶显示器件扫描行数并改善视角特性，其制造技术与ＴＮ器件相似，具有很大的应用价值。     

Model for Nanoscopic Domain Formation in Dipalmitoyl-PC/Dilauroyl-PC/Cholesterol Mixture

We describe the lyotropic liquid crystalline phase transitions in the lipid mixture dipalmitoil-PC/dilauroy-PC/cholesterol by 3D spin-1 lattice model. The formation of nanoscale domains with the characteristic size about 300 nm was studied in experiments on confocal fluorescence microscopy (CFM) (G. V. Feigenson and J. T. Buboltz, Biophys. J. 80, 2775 (2001)). The structure parameters of the lamellar vesicle in dipalmitoil-PC-rich phase, corresponding to these regions, are verified by numerical Monte Carlo simulations on the lattice. We point its superconductivity analogy properties at the region of phase stability for composition-dependent nanoscopic region.     

New method for measuring an optical property of a sample treated by FWA

In this article, a new method for measuring a total spectral radiance factor of a FWA‐treated sample illuminated by a specific standard illuminant is introduced. The method replaces an unstable real fluorescent standard by a bi‐spectral luminescent radiance factor data, which works as a virtual fluorescent standard (VFS) by knowing spectral intensity distributions of illuminations applied to the sample. The method utilizes two illuminations I₁ and I₂ whose relative spectral intensity distributions are different from each other and synthesizes a virtual illumination presenting the identical fluorescent spectral radiance factor to that presented by the standard illuminant with the VFS of the specific bi‐spectral luminescent radiance factor by linearly combining I₁ and I₂ with the suitable weighting factors. The applicability of the method is examined in principle by comparing ISO brightness and CIE whiteness index of fluorescent standard paper as a test sample obtained by this new method to the assigned values. © 2007 Wiley Periodicals, Inc. Col Res Appl, 32, 195–200, 2007     

Bioeompatibility of Compounds of Extracellular Matrix and Thermally Reversible Hydrogel

A new scaffold material composed of extracellular matrix （ECM） and thermal sensitive hydrogel （HG）, and evaluated its biocompatibility were investigated. We cultured bladder smooth muscle cells with this compound material, and then observed with phase contrast microscopy and scanning electron microscope （SEM） to assess the cell growth and morphology. The cell adhesion and proliferation were detected with MTT assay and cell count. Results show the ECM/HG compounds appeared as a net-like and red-stained construction with enough meshes and without any cellular fragments. 6 h after implantation, cells were observed adhere on the compounds and extend spurious along the fibers 12 h later. Under SEM even some ECM was observed to be secreted. MTT assay shows there was obvious statistic difference among 3 groups （P〈0.05）. ECM/HG compound materials show a good biocompatibility, which confirms that it would be an ideal tissue engineering scaffolds.     

明胶-异丙基丙烯酰胺水凝胶的溶胀性

以明胶和N -异丙基丙烯酰胺 (NIPAM )为原料 ,制备了明胶 -PNIPAM (聚N -异丙基丙烯酰胺 )水凝胶 ,研究不同的明胶 /NIPAM配比、温度、离子强度对其平衡溶胀度的影响。结果表明 :交联剂质量分数为 2 %时 ,当温度高于最低临界溶液温度 (LCST)值 ,水凝胶中明胶组分越多 ,凝胶的平衡吸水量越大 ;当温度低于LCST ,质量比为明胶 /NIPAM =5 /5 ,水凝胶的溶胀度最大。交联剂质量分数为 0 3%时 ,无论温度在LCST以上或以下 ,溶胀度都随明胶含量的增加而增加。离子强度对溶胀度的影响呈非单调性关系。     

An IR study on ion-specific and solvent-specific swelling of poly(N-vinyl-2-pyrrolidone) gel

Swelling degrees of poly(N-vinyl-2-pyrrolidone) (PVP) gel were measured in aqueous salt solutions and in water/organic solvent mixtures to find marked ion- and solvent-specificities. In order to investigate any correlation of those specificities with hydration or solvation of PVP, IR spectra band of the CO group was monitored by means of ATR method both for PVP gel and the relevant solution systems. Dependence of the peak frequency on the swelling ratio suggested that hydration of PVP carbonyl group in deswollen gel systems is different from that in the corresponding solution systems. In the solution systems, PVP carbonyl band showed a high-wavenumber shift for deswollen systems, which can be well correlated with changes in water proton charge through ionic hydration and with Gutmann's acceptor number of organic solvents. In the deswollen gel systems, the CO band showed a low-wavenumber shift, suggesting a strong hydration or doubly hydrated state. This unexpected behavior was interpreted by assuming an intermolecular hydrogen bond of two carbonyl groups intermediated by water molecules.     

功率因数的概念及测试方法探讨

随着理论的发展和技术的进步，功率因数的概念有了更深的内涵，本文就其概念作了说明，对测量方法作了探讨。     

共聚物水凝胶的合成及其溶胀性能研究

以过氧化二苯甲酰(BPO)为引发剂，合成了N-乙烯基吡咯烷酮(NVP)-甲基丙烯酸肛羟乙酯(HEMA)-甲基丙烯酸丁酯(BMA)共聚物水凝胶，可作为软性角膜接触镜材料。探讨了不同比例的NVP、HEMA、BMA对材料溶胀性能的影响。