A novel hydrogen peroxide sensor based on horseradish peroxidase immobilized on colloidal Au modified ITO electrode

A novel method to fabricate a hydrogen peroxide sensor was developed by immobilizing horseradish peroxidase (HRP) on colloidal An modified ITO conductive glass support. The cleaned glass support was modified with (3-aminopropyl)trimethoxysilane (APTMS) first to yield an interface for the assembly of colloidal An. Then 15 nm colloidal Au particles were chemisorbed onto the amine groups of the APTMS. Finally, HRP was adsorbed onto the surface of the colloidal An. The immobilized HRP displayed excellent electrocatalytical response to the reduction of hydrogen peroxide. The performance and factors influencing the resulted biosensor were studied in detail. The resulted biosensor exhibited fast amperometric response (within 5 s) to H2O2. The detection limit of the biosensor was 8.0 mumol l(-1), and linear range was from 20.0 mumol l(-1) to 8.0 mmol l(-1). Furthermore, the resulted biosensor exhibited high sensitivity, good reproducibility, and long-term stability.

溶胶一凝胶法合成Ni0.65Zn0.35Cu0.1Fe1.9O4/SiO2 纳米复合材料及其磁性能研究

通过溶胶-凝胶法合成了Ni0.65Zn0.35Cu0.1Fe1.9O4/SiO2纳米复合材料。借助XRD、TEM和VSM对纳米复合材料进行了表征，试验表明，当热处理温度达550℃，可得到分散于SiO2中的单相纳米NiZnCu铁氧体。纳米复合材料的磁学性质呈明显的温度依赖性。饱和磁化强度随热处理温度的提高而增加。

Investigation of charge-carrier injection characteristics in NPB/Alq3 heterojunction devices

The effect of copper phthalocyanine (CuPc) and LiF interfacial layers on the charge-carrier injection in NN'-di(naphthalene-l-yl)N,N'-diphenyl-benzidine (NPB)/tris(8-hydroxyquinoline) aluminium (Alq(3)) organic heterojunction devices have been studied through the analysis of current-voltage characteristics. The investigation clearly demonstrated that the hole injection into NPB from anode is Fowler-Nordheim (FN) tunneling and the electron injection into Alq3 from cathode is Richardson-Schottky (RS) thermionic emission. The barrier heights obtained from the FN and RS models proved that the band alignments for charge-carrier injection are greatly improved by the CuPc and LiF interfacial layers, which should fully clarify the role of the interfacial layer on the improvement of device performance.

Characterization of the microstructure of biaxially oriented polypropylene using preparative temperature-rising elution fractionation

Two commercial biaxially oriented polypropylene (BOPP) resins, resin A and resin B, having different processing properties, were fractionated by preparative temperature-rising elution fractionation (TREF). The TREF fractions were further characterized by gel permeation chromatography (GPC), gel permeation chromatography coupled with light scattering (GPC-LS), wide-angle X-ray diffraction (WAXD), and differential scanning calorimetry (DSC). GPC-LS did not find visible long-chain branching in either resin A or B. The results from TREF and DSC indicate that the fractional melting parameter f(T) may be used to predict the profile of the TREF cumulative weight distribution curve. GPC results show that the molecular weights of the fractions tend to increase with elution temperature. WAXD and DSC data show that the crystallinity of fractions does not increase monotonically with increase of elution temperature. There appears to be a maximum in the plot of crystallinity versus elution temperature. The high-speed BOPP resin A has a lower isotacticity but a homogeneous isotacticity distribution and a higher molecular weight but a broader molecular weight distribution than resin B.

聚β-羟基丁酸酯解聚酶的纯化及性质

对DS9701菌株产生的聚β-羟基丁酸酯(PHB)解聚酶进行了分离、纯化及有关性质的表征.通过SephadexG-100分离出两种PHB解聚酶(E1和E2),经聚丙烯酰胺凝胶电脉检测为一条谱带.E1的最适反应温度为40℃～45℃,稳定性优于E2,最适反应pH=4.0,稳定范围3.6～7.0,Km值为0.182g/L.E2的最适反应温度为40℃,pH=6.0,稳定范围4.0～8.0,Km值为0.65g/L.通过质谱仪测得E1的相对分子质量为4.5×104,E2的相对分子质量为4.4×104.

Alternating LB film of ferric oxide nanoparticles-copper phthalocyanine derivative and its gas sensitivity

Nanoparticulate ferric oxide - tris - (2,4-di-t-amylphenoxy) - (8-quinolinolyl) copper phthalocyanine Langmuir-Blodgett Z-type multilayers were obtained by using monodisperse nanoparticle ferric oxide hydrosol as the subphase. XPS data reveal that the nanoparticle ferric oxide exist as alpha -Fe2O3 phase in the films. Transition electron microscopic (TEM) image of the alternating monolayer shows that the film was highly covered by the copper phthalocyanine derivative and the nanoparticles were arranged rather closely. IR and visible spectra all give the results that the nanoparticles were deposited onto the substrate with the copper phthalocyanine derivative. The gas-sensing measurements show that the alternating LB film had very fast response-recovery characteristic to 2 ppm C2H5OH gas, and also sensitive to larger than 200 ppm NH3.

Crystal form transition during heating of solvent-induced crystalline syndiotactic polystyrene

The phase transition of two kinds of solvent-induced crystalline syndiotactic polystyrene (sPS). gamma-sPS and delta(c)-sPS, has been studied via WAXD and DSC. gamma-sPS transform to a-sPS at 195-225 degrees C before melt during heating, whereas delta(e)-sPS transform to first gamma-sPS and then a-sPS at 100-200 degrees C and 200-215 degrees C, respectively. The transition of delta(e)-gamma and gamma-a occurs for below melting point of sPS indicates they are all solid-solid transition.

TG-DTA properties of new nonlinear optical materials: K(2)Ln(NO3)(5)center dot 2H(2)O (Ln = La, Ce, Pr, Nd, Sm)

Single crystals of K(2)Ln(NO3)(5). 2H(2)O (KLnN) (Ln = La, Ce, Pr, Nd, Sm) were grown from aqueous solution. The thermogravimetric analysis and differential thermal analysis curves of KLnN demonstrate that the processes of dehydration, melting, irreversible phase transformation and decomposition of NO3- take place in sequence in the heating processes (except KCN). There are three stages in the decomposition of NO3- in KLnN (Ln = La, Nd, Sm) while two in KLnN (Ln = Ce, Pr). K(2)Ln(NO3)(5) is formed at about 225 degrees C by the reaction of KNO3 and Ln(NO3)(3). nH(2)O (Ln = La, Ce, Pr, Nd). (C) 2000 Elsevier Science Ltd. All rights reserved.

胺类化合物气相色谱保留指数与结构的相关性研究

应用Am指数和引力指数C1对在3种体系下的胺类化合物的气相色谱保留指数和结构进行了相关性研究，并运用最佳子变量集算法和人工神经网法进行了计算分析，在非极性固定相OV-101和极性固定相OV-225和NGA下均获得了比较好的相关模型。

Photochemical synthesis and crystal structure of a charge transfer salt [HMDH2][(H2PMoMo11O40)-Mo-v]center dot 2AA center dot 3H(2)O center dot DMF

The title supramolecular compound, [HMDH2][(H2PMoMo11O40)-Mo-V] . 2AA . 3H(2)O . DMF (HMD = hexamethylene diamine; AA=acetaldehyde; DMF=N,N-dimethyl formamide), has been photochemically synthesized by using elemental analysis, IR, solid diffusion reflectance, electronic spectra, ESR spectra and X-ray single-crystal analysis. The crystallographic data: triclinic, P (1) over bar, a=14.092(2), b=14.347(3), c=14.358(3)Angstrom, alpha = 75.10(3), beta = 80.70(3), gamma = 80.73(3)degrees, V = 2746.6(10)Angstrom (3), Z = 2, M-r = 2081.68, D-c=2.517g/cm(3), F(000) =1970, mu (MoK alpha) =2.766mm(-1). The structure has been refined to R =0.0832 and wR=0.2638, by full-matrix least-squares method. The title compound is composed of hexamethylene diamine, two acetaldehyde molecules, three water molecules, one N,N-dimethylformamide and [(H2PMoMo11O40)-Mo-V](2-) heteropoly anion.

己二胺-12-钼磷酸电荷转移盐的光化学合成与晶体结构

采用光化学法合成一种有机-无机电荷转移盐，（HMDH2）[H2PMo12O40]·AA·3H2O·DMF（HMD = 1,6-己二胺，AA = 乙醛，DMF = N,N-二甲基甲酰胺）超分子化合物。用元素分析，IR，固体漫反射电子光谱，ESR进行了表征。X-射线四圆衍射测定其晶体结构属三斜晶系，空间群 Pī，Mr=2081.68，晶胞参数a = 14.092(3)，b =14.347(3)，c =14.358(3)?，α=75.10(3)，β=80.70(3)，γ=80.73(3)°,V=2746.6(10)?3，Z=2，Dc=2.517g/cm3，F(000)=1970，μ(MoKα)=2.766mm- 1，全矩阵最小二乘法修正至R=0.0832，wR=0.2638。标题化合物是由1个质子化的1,6-己二胺、12-钼磷混合价杂多阴离子 [PMo12O40]4ˉ、3个水分子、2个乙醛分子和1个二甲基甲酰胺分子构成。

Synthesis, crystal structure and properties of H-8[P4W14O58Na4 (H2O)(20)] center dot 16H(2)O

A novel heteropoly tungstophosphates, H-8[P4W14O58Na4(H2O)(20)] . 16H(2)O, was synthesized by hydrothermal method and characterized by elemental analysis, IR spectrum and single-crystal X-ray structure analysis. The thermal stability of the compound was investigated by using TG-DTA. The crystal is triclinic system with space group P (1) over bar, a = 1. 137 9(2) nm, b=1. 363 2(3) nm, c=1. 627 1(3) nm; alpha=78. 20(3)degrees, beta=71, 20(3)degrees, gamma= 71. 62(3)degrees; V = 2. 252 5(8) nm(3), Z=1, M-r= 4 374. 38, D-c = 3. 225 mg/cm(3), mu = 18. 007 mm(-1), F(000)=1 972, R=0. 074 2, R-w=0. 200 4. The result of structure analysis shows that the anion of the compound consists of two PW7O29Na2(H2O)(10) subunits and two linked phosphorous atoms. A kind of microporous with size of 0. 661 4 nm X 0. 318 9 nm was formed in the crystal structure.

用仪器化冲击仪研究HIPS/SBS共混物的冲击性能

用JJ-20型仪器化冲击仪研究了HIPS/SBS共混物在组成为100/0、100/5、100/10、100/15、100/20和100/25质量比下样品的Izod缺口冲击性能。结果表明，在组成范围内，随着SBS含量的增加，样品的Izod缺口冲击强度随之增加。质量比为100/25样品的Izod缺口冲击强度值(225.9J/m)比质量比为100/0的样品(108.7J/m)增加了1倍以上。通过对冲击断裂过程的分析表明，冲击强度的提高主要是由于缺口根部应力集中产生塑性区所消耗的裂纹引发能的提高引起的，而裂纹扩展能基本没有多大变化

等离子体平板显示用发光材料

本文介绍了PDP用荧光粉的基本情况及其应用特性。归纳出基团敏化带位置的一般规律及阳离子对基团敏化带波长位移的影响。并指出，提高发光效率，改善荧光粉的热稳定性和辐照稳定性，开发新型稀土荧光粉等具有重要意义。