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991.
本文提出一种制备导电电路的方法。以纳米铜为导电填料,以光固化树脂为连接剂,制备含铜光固化油墨,利用丝网印刷方法获得含有纳米铜的图案,利用铜与银盐间的置换反应,将铜纳米粒子图案通过原位体积加成转化为导电银图案。研究结果表明,铜图案不具有导电性,而置换反应生成的银图案具有导电性,且导电能力受铜含量、银盐浓度、光照时间、浸泡反应时间等因素影响,本实验中获得的最高电导率为1.25×105 S/m,导电线路具有良好的耐弯曲、耐疲劳性能,同时兼具优异的可修复性能,为导电线路的制备提供了常温下简单有效、成本低廉的实现方法,具有重要的参考价值。 相似文献
992.
The palladium-substituted tungstoantimonate(III) [Cs(2)Na(H(2)O)(10)Pd(3)(alpha-SbW(9)O(33))(2)](9-) (1) has been synthesized and characterized by IR, elemental analysis, and electrochemistry. Single-crystal X-ray analysis was carried out on Cs(3)KNa(5)[Cs(2)Na(H(2)O)(10)Pd(3)(SbW(9)O(33))(2)].16.5H(2)O, which crystallizes in the monoclinic system, space group P2(1)/m, with a = 13.3963(13) A, b = 19.5970(19) A, c = 18.1723(17) A, beta = 100.416(2) degrees, and Z = 2. Polyanion 1 represents the first structurally characterized palladium(II)-substituted polyoxometalate. The title polyoxoanion consists of two (alpha-Sb(III)W(9)O(33)) Keggin moieties linked via three Pd(2+) ions leading to a sandwich-type structure. The palladium centers are equivalent, and they are coordinated in a square-planar fashion. The central belt of 1 contains also one sodium and two cesium ions which reduces the symmetry of the polyanion to C(2)(v)(). Polyanion 1 was synthesized in good yield by reaction of Pd(CH(3)COO)(2) with Na(9)[SbW(9)O(33)] in aqueous acidic medium (pH 4.8). A cyclic voltammetry study of polyanion 1 in a pH 5 medium gives essentially the same characteristics as those observed for the deposition of Pd(0) on the glassy carbon electrode surface from Pd(2+) solutions. The film thickness increases with the number of potential cycles or the duration of potentiostatic electrolysis. The particularly sharp hydrogen sorption/desorption pattern indicates the excellent quality of the Pd(0) deposit from polyanion 1. 相似文献
993.
一维螺旋链状配位聚合物[Cu(p-BDOA)(2,2′-bipy)·H2O]n的合成与表征(英) 总被引:5,自引:0,他引:5
A new copper(Ⅱ) coordination polymer, [Cu(p-BDOA)(2,2′-bipy)·H2O]n ( p-BDOA2-=benzene-1,4-dioxyacetate dianion; 2,2′-bipy=2,2′-bipyridine) has been synthesized and characterized by elemental analysis, IR, TG and single crystal X-ray diffraction. The Crystal crystallizes in orthorhombic system, the space group is P212121, with the unit cell parameters a=0.698 4(1) nm, b=1.559 7(3) nm, c=1.750 6(4) nm and V=1.906 8(7) nm3, Mr=461.91, Z=4, R=0.057 5, wR=0.078 3. Each copper(Ⅱ) atom is six-coordinated and displays a distorted square pyramidal geometry with a one-capped base by one very long semicoordinate Cu-O(carboxylate) bond. Adjacent Cu(Ⅱ) ions are bridged by carboxylate groups, resulting in a one-dimensional helical chain. The adjacent Cu…Cu distance within the polymeric chain is 1.348 4 nm. Furthermore, such chains are linked through hydrogen bonds and π-π stacking interactions to form supramolecular network. CCDC: 219234. 相似文献
994.
一维链状的3-羧基苯氧乙酸铜配位聚合物[Cu(3-cpoa)(phen)(H2O)]n的合成与晶体结构 总被引:2,自引:0,他引:2
A novel coordination polymer [Cu(3-cpoa)(phen)(H2O)]n(3-cpoa2-=3-carboxylphenoxyacetate, phen=1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR spectra and single crystal X-ray diffraction. Crystallographic facts are as follows: monoclinic crystal system, space group P21/n, a=0.688 96(14) nm, b=1.652 3(3) nm, c=1.651 1(3) nm, β=95.20(3)°, V=1.871 9(6) nm3, Z=4, Dc=1.618 g·cm-3, F(000)=932, μ=1.211 mm-1,R=0.048 2 and wR=0.062 2. The copper atom exhibits a distorted square pyramidal coordination geometry, involving two oxygen atoms of different 3-cpoa2- ligands, two nitrogen atoms of 1,10-phen ligand and one coordinated water molecule. The copper atoms are bridged by 3-cpoa2- ligand, forming a one-dimensional chain along c axis. The distance of adjacent Cu…Cu is 0.916 6(4) nm. A three-dimensional network structure is constructed by the intermolecular hydrogen bond and π-stacking interactions. CCDC: 219724. 相似文献
995.
Mn(II)-sodium dodecyl sulphate complex (Mn(II)-SDS) is used to mimic the active group of peroxidase. The catalytic characteristic of this mimic enzyme catalyst in the oxidation reaction of fluorescence substrate, tetraethyldiaminoxanthyl chloride (Pyronine B (PB)), with hydrogen peroxide has been studied. The experimental results show that Mn(II)-SDS complex has similar catalytic activity that of peroxidase. The steady-state catalytic rate depends upon mimic enzyme and substrate concentrations, and the Michaelis-Menten parameters Km, Vmax and Kcat are 7.6×10−6 M, 7.9×10−7 M s−1 and 7.9 s−1, respectively. The catalytic activity of Mn(II)-SDS complex is compared with those of HRP and Hemin. Though the catalytic activity of Mn(II)-SDS complex is 15.9% of that of HRP, it can catalyze the oxidation reaction of PB with hydrogen peroxide lead to fluorescence quenching of PB. Under optimum conditions, linear relationship between fluorescence quenching F0/F and concentration of H2O2 is in the range of (0.0-3.6) × 10−7 M. The detection limit is determined to be 3.0×10−9 M. By coupling this mimic catalytic reaction with the catalytic reaction of glucose oxidase (GOD), glucose can be detected. Linear relationship between F0/F and concentration of glucose is in the range of (0.0-1.4) × 10−7 M. The detection limit is determined to be 4.2×10−9 M. This method is applied to the determination of glucose in human serum and the results are in good agreement with the phenol-4-aminoantipyrine (4-AAP). 相似文献
996.
Ke Long WANG Zhi Ning WEN Fu Sheng NIE Meng Long LI 《中国化学快报》2005,16(8):1133-1136
In recent years, methods of protein sequences analysis have been gradually evolved into two directions: One is based on the models of probability and statistics1-4; the other is based on the digital signal processing technologies 5-8. The latter mainly converts the protein character sequences into digital signals and uses some signal processing methods to analyze them, i.e., fast Fourier transform (FFT). However, it is still unsolved how to characterize the protein sequences accurately with … 相似文献
997.
本文报道了一种测定紫锥花草药中咖啡酸、对羟基苯甲酸、对-香豆酸、原儿茶酸、丁香酸、阿魏酸、香草酸、咖啡奎尼酸、洋蓟酸、菊苣酸和紫锥花苷等11种酚类化合物的高效液相色谱分析方法。本法可应用于各种紫锥花草药中酚类化合物的测定。结果表明,在紫锥菊种属中含量最多的酚类化合物是菊苣酸、咖啡奎尼酸和紫锥花苷;在狭叶紫锥菊种属中含量较丰的是紫锥花苷和菊苣酸;而在白花紫锥菊种属中则以紫锥花苷以含量较多。 相似文献
998.
IntroductionProteindeterminationisalwaysimportantinclinicalapplications .Newmethodsincludingspcetrophotometry ,1fluorometry2 andchemiluminicence3 ,4 arecontinuouslybe ingdeveloped .Pasternacketal.5,6developedatech niquetomeasuretheintensityofscatteringlightusi… 相似文献
999.
The novel Ru(II)-supported heteropolytungstates [Ru(dmso)(3)(H(2)O)XW(11)O(39)](6-)(X = Ge, Si) have been synthesized and characterized by single-crystal X-ray diffraction, multinuclear NMR ((183)W, (13)C, (1)H, (29)Si) and IR spectroscopy, elemental analysis and electrochemistry. The novel polyanion structure consists of a Ru(dmso)(3)(H(2)O) unit linked to a monolacunary [XW(11)O(39)](8-) Keggin fragment via two Ru-O-W bonds resulting in an assembly with C(1) symmetry. Polyanions 1 and 2 were synthesized by reaction of cis-Ru(dmso)(4)Cl(2) with [A-alpha-XW(9)O(34)](10-) in aqueous, acidic medium (pH 4.8). Tungsten-183 NMR of 1 leads to a spectrum with 11 peaks of equal intensity, indicating that the solid-state structure is preserved in solution. Electrochemistry studies revealed that 1 and 2 are stable in solution at least from pH 0 to 7, even in the presence of dioxygen. Their cyclic voltammetry patterns show mainly two two-electron reversible W-waves, those of the Si derivative 2 being located at slightly more negative potentials than those of the Ge derivative 1. The observed stability of 1 and 2 might be attributed to a stabilization of the Ru-center both by the strongly bound dmso ligands and the Keggin moiety. This stabilization drives the redox waves of Ru outside the accessible potential range. However, conditions were found to reveal, at least partially, the redox behavior of Ru in 1 and 2. 相似文献
1000.
Li JF Wei YX Ding LH Dong C 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2003,59(12):2759-2766
The inclusion complexes of beta-cyclodextrin (beta-CD) and HP-beta-cyclodextrin (HP-beta-CD) with a kind of tanshinone, cryptotanshinone (CTan) were investigated by using spectrophotometry. Stable inclusion complexes were established in solution and in solid state and were characterized by UV, IR and 1H NMR spectra, respectively. The optimum pH for inclusion is about 7.5. Stoichiometry of the inclusion complex is 1:1. The stabilities of beta-CD and HP-beta-CD to CTan were in the order: beta-CD相似文献