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121.
应用 Jobin-Yvon U—1000型拉曼光谱仪和LABRAMI型拉曼光谱系统研究了 3种卟啉TOHPP、TamPP和TSPP在化学还原沉积法制备的银膜上的RS和SERS光谱特征。结果表明:化学还原法制备的银膜可以作为这几种卟啉的拉曼增强活性载体。这3种卟啉在获谱的过程中都形成二聚态化合物和发生银离子搀和作用,较长的放置和测谱时间有利于银离子的搀和。 相似文献
122.
《Electroanalysis》2005,17(2):155-161
A highly sensitive immunosensor based on immobilization of hepatitis B surface antibody (HBsAb) on platinum electrode (Pt) modified silver colloids and polyvinyl butyral (PVB) as matrixes has been developed for potentiometric immunoanalysis to detect hepatitis B surface antigen (HBsAg) in this study. HBsAb molecules were immobilized successfully on nanometer‐sized silver colloid particles associated with polyvinyl butyral on a platinum electrode surface. The modification procedure was electrochemically monitored by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). The HBsAb‐silver‐PVB‐modified electrode exhibited direct electrochemical behavior toward HBsAg. The factors influencing the performance of the resulting immunosensor were studied in detail. More than 94.7% of the results of human serum samples obtained by this method were in agreement with those obtained by enzyme‐linked immunosorbent assays (ELISAs). The resulting immunosensor exhibited a sigmoid curve with log HBsAg concentration, high sensitivity (39.8 mV/decade), wide linear range from 16.0 to 800 ng mL?1 with a detection limit of 3.6 ng mL?1, fast potentiometric response (<3 min) and long‐term stability (>4 months). The response mechanism of the immunosensors was also studied with AC impedance techniques. 相似文献
123.
124.
Ramón Puyané Isabelle Guy Renaud Metz 《Journal of Sol-Gel Science and Technology》1998,13(1-3):575-578
The ceramic microstructure, the chemical homogeneity of specific dopants and the mechanical integrity of a varistor disc are critical parameters in determining the transient voltage suppression features of these devices. The material properties and overall quality of the starting ceramic powders used to produce such components are essential in achieving the desired properties. The present work describes a novel chemical method developed to produce doped zinc oxide powders and an industrial scale manufacturing process for the production of final varistor blocks for surge arrester applications. The results are compared with those obtained when using standard varistor powder made by the mixed oxide route is used. All the fundamental electrical properties of the discs have been determined and correlated with the relevant manufacturing steps. 相似文献
125.
Martina Nveke Peter G. Jones Armand Blaschette Dietmar Schomburg Heiko K. Cammenga Matthias Epple 《无机化学与普通化学杂志》1993,619(6):1027-1036
Polysulfonyl Amines. XLI. A Silver(I) Hydrate with an Unusual Composition: Characterization of Tetrakis(dimesylamido)aquatetrasilver(I) [Ag4(N)SO2CH3)2}4(H2O)] by X-Ray Diffraction and Thermal Analysis The title compound is obtained by crystallizing AgN(SO2CH3)2 from water at room temperature. Crystallographic data (at ?95°C): Triclinic space group P1 , a = 864.6(4), b = 1 211.2(5), c = 1 399.1(5) pm, α = 90.97(3), β = 90.90(3), γ = 98.25(4)°, V = 1.4496 nm3, Z = 2, Dx = 2.608 Mg m?3. The four independent silver atoms and the water molecule form zigzag chains Ag(1)-Ag(2)-(μ-H2O)-Ag(3) …? Ag(4) …? Ag(1′) with distances Ag(1)-Ag(2) 309.7, Ag(2)-O(w) 241.8, O(w)-Ag(3) 241.4, Ag(3) …? Ag(4) 342.9, Ag(4) …? Ag(1′) 361.4 pm. The catenated silver atoms are further connected by the dimesylamide anions acting as tridentate bridging (α-O, N, ω-O)-ligands. The resulting strands are interconnected into layers through one O(S)-Ag′ contact (247 pm) and one hydrogen bond O(w)-H(l) …? O′(S) per repeating unit. Between the layers, a weak O(S) …? Ag″ interaction (271 ptn) and a hydrogen bond O(w)-H(2) …? O(S) per repeating unit are observed. The silver atoms Ag(l) to Ag(4) display the coordination numbers 5 [NO,Ag(2), distorted trigonal bipyramid], 5[NO2,O(w)Ag(I), distorted trigonal bipyramid], 5[O4,O(w), trigonal bipyramid], and 2 + 1 (N2, li-near; plus a secondary Ag …? 0 contact). The dehydration of the title compound and a solid-solid phase transformation in anhydrous AgN(SO2CH3)2, were quantitatively investigated by thermoconductometry and time- and temperature-resolved X-ray diffractometry (TXRD). 相似文献
126.
本文研究了银(Ⅰ)-硫脲-四正丁基溴化铵体系的电致化学发光(ECL)。发现在正矩形脉冲下,银对含有硫脲的TBABr溶液的ECL有明显催化作用,银(Ⅰ)的浓度在1.4×10 ̄(-8)~3.5×10 ̄(-6)mol/L范围内与ECL强度呈良好线性关系。检出限为9.0×10 ̄(-9)mol/L相对标准偏差为5%。用于天然水中银的测定,获得较满意的结果。 相似文献
127.
粉末化学镀法制备的NiB/TiO2非晶态合金催化剂对环丁烯砜加氢反应的催化性能 总被引:7,自引:0,他引:7
采用诱导沉积法及粉末化学镀法分别制备了纯态NiB及负载型NiB/TiO2非晶态合金催化剂.用XRD,ICP,SEM,TEM和DSC等手段对催化剂的物性及TiO2载体与NiB非晶态合金之间的相互作用进行了表征,考察了非晶态合金的结构、组成、形貌和热稳定性,并将其用于环丁烯砜加氢反应中.结果表明,相对于NiB而言,NiB/TiO2催化剂具有优良的热稳定性和催化活性,这缘于NiB和TiO2载体之间的相互作用及载体的分散作用. 相似文献
128.
Summary Rare earth elements 1,3,5-benzenetricarboxylates were prepared as solids of the general formula Ln(C9H3O6)·nH2O, where n=6 for La-Dy and n=4 for Ho-Lu,Y. Their solubilities in water at 293 K are of the order 10-4-10-6 mol dm-3. The IR spectra of the complexes indicate that the carboxylate groups are bridging and bidentate chelates. Hydrated 1,3,5-benzenetricarboxylates
lose water molecules during heating in one step (La-Tb), two steps (Y, Ho-Tm) or three steps (Dy, Yb, Lu). The anhydrous complexes
are stable up to 573-742 K and decompose to oxides (Ce-Lu) at higher temperatures. 相似文献
129.
测定了Ag+离子在笼形聚偕胺肟树脂(CAO)及其酸、碱处理产物(ACAO、BCAO)上的吸附容量.Ag+离子在BCAO树脂上吸附容量较高,但同非选择性吸附,在ACAO上的吸附容量则与处理树脂的酸的pKa值有关.用高pKa值的硼酸、苯酸和对氨基酚处理所得的ACAO树脂的吸附容量接近BCAO树脂的水平,认为是胶后胺肟基发生互变异构所致.吸附动力学表明Ag+离子在H3BO3/ACAO和C6H5OH/ACAO树脂上进行多层吸附.在吸附中伴随有氧化还原反应并生成Ag(O)微晶的过程. 相似文献
130.
The influence of various factors such as solubility, the oxidation of the membrane, and the contamination of the solution, on the experimental values of the selectivity coefficients of solid state sulphide ion selective electrodes is discussed. A new method for the evaluation of very small selectivity coefficients, based on the addition of reagents forming complexes or insoluble salts with the main ion, is proposed. By means of this method, selectivity coefficients for silver, copper, cadmium and lead ion selective electrodes have been determined, which are in far better agreement with thermodynamic values than those described in the literature. 相似文献