普鲁士蓝和茈四甲酸二酐衍生物膜修饰的过氧化氢生物传感器

以玻碳电极（GCE）为基底,采用恒电位法沉积一层普鲁士蓝（PB）,然后将j芑四甲酸二酐衍生物（PTC-NH,）自组装到其表面,形成既带氨基功能团,又可有效防止PB渗漏的导电膜。通过静电吸附和共价键合作用固定纳米金和辣根过氧化物酶（HRP）的复合物,从而制得性能优良的过氧化氢（H2O2）生物传感器。采用循环伏安法（CV）和计时电流法,考察了传感器的电化学性能。实验表明,本传感器具有灵敏度高、线性范围宽、检出限低、稳定性好、抗干扰能力强等特点。其线性范围为2．0×10^-6～1．4×10^-5mol／L;检出限为8．3×10^-7mol／L（S／N=3）。     

纳米金/3-氨丙基-三乙氧基硅烷修饰传感器电化学检测NO-2

将3-氨丙基-三乙氧基硅烷（ATS）修饰在玻碳电极表面,再自组装一层纳米金,制备了一种新型NO2^-的电化学传感器。该修饰电极对NO2^-有较好的催化作用。在pH为3时,NO2^-的氧化峰电流与其浓度在5．0×10^-7～1．0×10^-3mol／L范围内呈良好的线性关系,检出限可达2．0×10^-7mol／L。方法具有较高的灵敏度和较好的重现性。     

己硫醇二茂铁复合金纳米粒子修饰电极对多巴胺的催化性能研究

将自行合成的己硫醇二茂铁自组装于金纳米粒子表面,获得己硫醇二茂铁复合金纳米粒子（Au@S（CH2）6Fc）。采用滴涂法将制备的复合纳米粒子固定于玻碳电极表面,制备Au@S（CH2）6Fc修饰电极,采用循环伏安法对修饰电极的电化学性能进行考察。将制备的修饰电极用于对神经递质多巴胺（DA）的催化氧化性能研究。结果表明,该修饰电极对DA具有显著的催化氧化作用,线性范围为1.0×10^-6-2.6×10^-3mol/L,检出限为3.0×10^-7mol/L。     

纳米铂电极的制备及其电化学行为

以镍铬合金为基体,采用电化学方法在其表面沉积制备了纳米Pt电极,用SEM对电极的形貌进行了表征,以亚铁氰化钾为分子探针考察了Pt电极的电化学性能。结果表明该电极对亚铁氰化钾具有稳定、灵敏的电化学响应,并对H2O2的电化学还原具有良好的催化活性。H2O2峰电流与其浓度在0.03-1.0 mmol/L范围内呈良好的线性关系,检出限（S/N=3）为7×10^-6mol/L。相同实验条件下,该纳米Pt电极的催化活性远高于纯Pt电极。     

荧光探针法研究铜离子-姜黄素体系中^1O2的反应机理及在O2^·-存在下^1O2的测定

以1,3-二苯基异苯并呋喃（1,3-Diphenylisobenzofuran,DPBF）为荧光探针,研究了姜黄素（Curcumin,CUR）在铜离子催化下产生的单线态氧（^1O2）,其反应机理为姜黄素与溶液中的氧分子快速作用产生O2^·-和H2O2等活性氧物种,同时Cu^2＋与姜黄素形成复合物,再与H2O2形成过氧化物过渡态,过氧化物进一步与H2O2发生类Haber-Weiss反应生成^1O2,且只有Cu^2＋和Cu^＋离子可催化姜黄素并产生^1O2．^1O2在1．37×10^-2～3．66×10^-7mol／L浓度范围内与荧光强度下降值△IF有良好的线性关系。检出限为4．12×10^-4mol／L。     

5-HIAA在MWNT-Nation修饰电极上的伏安行为

研究了在磷酸盐缓冲溶液（pH7．0）中，5-羟基吲哚乙酸（5-HIAA）在MWNT-Nafion修饰电极上的电化学行为。5-HIAA在MWNT-Nafion修饰电极上出现一个灵敏的氧化峰。与裸玻碳电极相比，MWNT—Nation修饰电极提高5-HIAA的氧化峰电流。优化了各项测定参数，建立了一种直接测定HIAA的电分析方法。富集电位为-0．5V，富集时间为300s，氧化峰电流与5-HIAA的浓度在9．95×10^-5～7．98×10^-3mol／L之间有良好的线性关系。检出限为2．5×10^-6 mol／L。     

米托蒽醌分子印迹聚邻氨基酚敏感膜传感器的研制

在弱酸性条件下,在金电极上以邻氨基酚为单体和交联剂,米托蒽醌为模板分子,用循环伏安法电聚合成米托蒽醌分子印迹聚邻氨基酚敏感膜传感器。该传感器对米托蒽醌具有良好的选择性和敏感度,米托蒽醌浓度分别在2.0×10^-7—1.0×10^-5mol／L及1.0×10^-5—5.0×10^-5mol／L范围内与峰电流减小量呈线性关系,检出限为1.2×10^-7mol／L。本文同时对分子印迹膜的结构和性能进行了探讨与研究。     

流动注射化学发光法测定黄藤素

碱性条件下,铁氰化钾氧化鲁米诺产生化学发光,黄藤素对该体系的化学发光信号具有显著的增强作用。基于此,建立了一种直接测定黄藤素的流动注射化学发光分析新方法。该方法的线性范围为6.0×10-10－3.0×10^-8mol／L（r=0.9956）和3.0×10^-8－3.0×10^-6mol／L（r=0.9981）,检出限为2.5×10^-10mol／L（3σ）。对1.0×10^-9mol／L和1.0×10^-7mol／L的黄藤素连续平行测定11次,其相对标准偏差分别为3.5％和0.73％。该方法用于药物和体液中黄藤素的分析,回收率在96％-102％之间。     

酶催化动力学光度法测定H2O2

H2O2能够氧化偶氮染料刚果红使之褪色,而模拟酶—血红蛋白对其具有催化作用。据此建立了一种以刚果红为指示剂的H2O2-刚果红-血红蛋白酶催化反应体系测定痕量H2O2的新方法。确定了反应的最佳条件,体系的酸度为pH10.7的NH3-NH4Cl缓冲溶液,最大吸收波长为497 nm。该法的线性范围为8.0×10^-8-8.0×10^-5mol/L,检出限为1.97×10^-9mol/L,表观摩尔吸光系数为4.6×10^4L.mol-1.cm^-1。该方法可用于雨水及消毒水中H2O2的测定。     

基于纳米MnO2的免标记型DNA电化学生物传感器用于大肠杆菌的测定

以室温固相合成法制备纳米MnO2,通过壳聚糖（CHIT）的成膜效应将纳米MnO2固定在玻碳电极表面。DNA在MnO2/CHIT膜上的固定和杂交通过循环伏安和电化学交流阻抗进行表征。以电化学阻抗免标记法检测目标DNA,固定于电极表面的DNA探针与目标DNA杂交后使电极表面的电子传递电阻增大,以此作为检测信号可以高灵敏度地测定目标DNA。电化学阻抗谱检测大肠杆菌基因片段的线性范围为2.0×10^-11 ～2.0×10^-6mol/L,检出限为1.0×10^-12mol/L。     

Sc2MgGa2 and Y2MgGa2

Scandium magnesium gallide, Sc₂MgGa₂, and yttrium magnesium gallide, Y₂MgGa₂, were synthesized from the corresponding elements by heating under an argon atmosphere in an induction furnace. These intermetallic compounds crystallize in the tetragonal Mo₂FeB₂‐type structure. All three crystallographically unique atoms occupy special positions and the site symmetries of (Sc/Y, Ga) and Mg are m2m and 4/m, respectively. The coordinations around Sc/Y, Mg and Ga are pentagonal (Sc/Y), tetragonal (Mg) and triangular (Ga) prisms, with four (Mg) or three (Ga) additional capping atoms leading to the coordination numbers [10], [8+4] and [6+3], respectively. The crystal structure of Sc₂MgGa₂ was determined from single‐crystal diffraction intensities and the isostructural Y₂MgGa₂ was identified from powder diffraction data.     

Zur Kenntnis der Dialkalimetalldichalkogenide β-Na2S2, K2S2, α-Rb2S2, β-Rb2S2, K2Se2, Rb2Se2, α-K2Te2, β-K2Te2 und Rb2Te2

On Dialkali Metal Dichalcogenides β-Na₂S₂, K₂S₂, α-Rb₂S₂, β-Rb₂S₂, K₂Se₂, Rb₂Se₂, α-K₂Te₂, β-K₂Te₂ and Rb₂Te₂ The first presentation of pure samples of α- and β-Rb₂S₂, α- and β-K₂Te₂, and Rb₂Te₂ is described. Using single crystals of K₂S₂ and K₂Se₂, received by ammonothermal synthesis, the structure of the Na₂O₂ type and by using single crystals of β-Na₂S₂ and β-K₂Te₂ the Li₂O₂ type structure will be refined. By combined investigations with temperature-dependent Guinier-, neutron diffraction-, thermal analysis, and Raman-spectroscopy the nature of the monotropic phase transition from the Na₂O₂ type to the Li₂O₂ type will be explained by means of the examples α-/β-Na₂S₂ and α-/β-K₂Te₂. A further case of dimorphic condition as well as the monotropic phase transition of α- and β-Rb₂S₂ is presented. The existing areas of the structure fields of the dialkali metal dichalcogenides are limited by the model of the polar covalence.     

The alkali hypophosphites KH2PO2, RbH2PO2 and CsH2PO2

The structures of the hypophosphites KH₂PO₂ (potassium hypophosphite), RbH₂PO₂ (rubidium hypophosphite) and CsH₂PO₂ (caesium hypophosphite) have been determined by single‐crystal X‐ray diffraction. The structures consist of layers of alkali cations and hypophosphite anions, with the latter bridging four cations within the same layer. The Rb and Cs hypophosphites are isomorphous.     

Electrochemical study of (NEt4)2Cl2FeS2MoS2 and (NEt4)2Cl2FeS2MoS2FeCl2

Summary The ability of [MoS₄]^2–, anions to be used as ligands for transition metal ions has been widely demonstrated, especially with Fe²⁺. The present study has been restricted to linear complexes such as (NEt₄)₂ [Cl₂FeS₂MoS₂] and (NEt₄)₂[Cl₂FeS₂MoS₂FeCl₂]. Their electrochemical properties are described: upon electrochemical reduction, these compounds yield MoS₂, as a black precipitate, and an iron complex in solution, assumed to be [SFeCl₂]^2–. The electrochemical reduction goes through two electron transfers, coupled with the breakdown of the molecular skeleton: a DISPl and an ECE mechanism. Depending on the solvent, the following equilibrium may be observed: [Cl₄Fe₂MoS₄]^2–[Cl₂FeMoS₄]^2–+FeCl₂. The equilibrium constant, K_D, was evaluated by differential pulse polarography. K_D is tightly related to the donor number of the solvent.     

Formal [(2+2)+2] and [(2+2)+(2+2)] nonconjugated dienediyne cascade cycloadditions

[reaction: see text] Fluoranthene 2 and heptacycle 3 are easily accessible from the reaction of diyne 1 and norbornadiene (NBD) in the presence of the rhodium catalyst. The unusual [(2+2)+(2+2)] adduct 3 was confirmed by the X-ray crystal structure analysis.     

Thermal decomposition of Me3SnO2PCl2, Me2Sn(O2PCl2)2 and Ph3SnO2PCl2

TG and DTA studies on Me₃SnO₂PCl₂, Me₂Sn(O₂PCl₂)₂ and Ph₃SnO₂PCl₂ were carried out under dynamic argon atmosphere. The results show that the decomposition proceeds in different stages leading to the formation of Sn₃(PO₄)₂ as a stable product. This compound was characterized by IR spectroscopy. Decomposition schemes involving reductive elimination reactions were proposed.     

The bivalent metal hypophosphites Sr(H2PO2)2, Pb(H2PO2)2 and Ba(H2PO2)2

The structures of isomorphous monoclinic strontium and lead bis­(di­hydrogenphosphate), Sr(H₂PO₂)₂ and Pb(H₂PO₂)₂, and orthorhombic barium bis­(di­hydrogen­phos­phate), Ba(H₂PO₂)₂, consist of layers of hypophosphite anions and metal cations exhibiting square antiprismatic coordination by O atoms. The Sr and Pb atoms are located on sites with point symmetry 2, and the Ba atoms are on sites with point symmetry 222. Within the layers, each anion bridges four metal cations.