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81.
The solvothermal reaction of CuCl(2).2H(2)O with pyridine-4-thiol and ethanol yielded a novel photoluminescent 3-D polymeric complex with an interesting decorated diamondoid network that is constructed of decanuclear copper(I) cluster units and mu(4)-Cl ligands. The in situ generation of CuSO(4).5H(2)O implies the spontaneous occurrence of desulfurization and redox reactions in the present system. 相似文献
82.
现场表面拉曼光谱研究Fe-Mo合金诱导共沉积 总被引:1,自引:0,他引:1
现场表面拉曼光谱结果显示,在0.2mol·L-1Na2MoO4,pH=4.0的溶液中,电位正于0.5V(vsSCE)时只观察到多钼酸盐的拉曼峰(940、880和450cm-1).负于-0.5V时,出现中心位于730cm-1的宽峰.同时电极表面有蓝色膜生成.表明混合氧化态(MO(Ⅳ),MO(Ⅴ))氧化膜的形成.730cm-1的峰在-1.9V时仍然存在,说明氧化膜没有被进一步还原.在钼酸钠溶液中同时含有0.1mol·L-1FeSO4和0.2mol·L-1柠檬酸时,中间态氧化膜的拉曼峰的中心移到740cm-1.且峰强度随着电位从-1.3V负移到-1.9V而逐渐减弱并最终消失.电极表面沉积层呈银白色,说明由于Fe2 的存在,钼的中间态氧化膜的结构发生了变化,能够被进一步还原形成Fe-Mo合金,表现出诱导共沉积的特征. 相似文献
83.
Yao Zu Liao Mei Hua Xin Ming Chun Li Sheng Su College of Materials Science Engineering Huaqiao University Quanzhou China 《中国化学快报》2007,18(2):213-216
O-Lauroyl chitosan/poly(L-lactide) (OCS/PLLA) blend membranes with different compositions were prepared by solution-casting approach using chloroform as common solvent. The experimental results of FT-IR, DSC and WAXD indicated that inter-association hydrogen-bond interactions existed between OCS and PLLA in the blend membranes. And SEM observation confirmed that the blend membranes with suitable compositions were compatible. 相似文献
84.
The title compounds 6a—6f were prepared with high yield via intramolecular Wittig reaction of methyl 3-perfluoroalkyl-6-peifluoroacyl-2-triphenylphosphoranylidenchex-3,5-dienoates (5a—5i) which were obtained from the reaction of 3-perfluoroacylprop-2-enylidenetriphenylphosphoranes (3a—3c) with methyl perfluoroalkynoates (4a—4c). 相似文献
85.
Zr0.5Ti0.5O2(ZT) and Zr0.25Ti0.25Al0.5O2(ZTA) mixed oxides were prepared by co-precipitation method and characterized by low temperature adsorption-desorption, XRD and NH3-TPD. The activity of Pt/Zr0.5Ti0.5O2 and Pt/ Zr0.5Ti0.5Al0.5O2 catalysts was evaluated using the simulated gases. The results show that ZTA samples exhibit higher specific surface area, larger pore volume and proper surface acidic amount and acidity in comparison with ZT. The results of the catalytic test indicate that Pt/ZT and Pt/ZTA catalysts exhibit excellent low-temperature catalytic activity and lower light-off temperatures of hydrocarbon, carbon monoxide and nitrogen oxides, especially better conversion for nitrogen oxides (NOx). The addition of Al2O3 into ZT enhanced the anti-aging property of Pt/ ZTA catalysts due to the excellent textural, structural, surface acidity and thermal stability. 相似文献
86.
87.
A new quartz crystal impedance sensing technique for the assay of hyaluronidase (HAse) activity is presented. It is based on the changes in viscosity and density during the enzymatic hydrolysis of hyaluronic acid (HA) by HAse. The variations of equivalent circuit parameters of piezoelectric quartz crystal (PQC) during the enzymatic degradation are discussed. The motional resistance shift curves indicate that the viscosity of the test solutions decreases during the hydrolysis process. The initial hydrolysis rates of HA are obtained from changes in viscosity and density as a function of incubation time. Kinetic parameters (the Michaelis constant K(m) and the maximum hydrolysis rate V(max)) of the degradation reaction are estimated by using a linear Lineweaver-Burk plot in this work. The K(m) was 0.44+/-0.03 mg.ml(-1) and the V(max) was -(5.29+/-0.36)x10(-3) kg.m(-2).s(-1/2).min(-1). 相似文献
88.
Shihui Si Fenglian Ren Wen Cheng Shouzhuo Yao 《Analytical and bioanalytical chemistry》1997,357(8):1101-1105
To obtain new coatings for the preparation of piezoelectric immunosensors, the anodic polymerization of o-aminophenol (oAP),
o-phenylenediamine (oPD) and m-phenylenediamine (mPD) onto a gold-plated crystal has been studied. The possibility of immobilizing
an antibody (anti-S. paratyphi A) onto the crystal via the electropolymerized films was investigated. The poly-mPD film gave
the best results for immobilizing the antibody. With antibodies crosslinked on the poly-mPD film, a piezoelectric immuno-assay
for the detection of S. paratyphi A was proposed. The shift (ΔF=F20s−F400s, Hz) between the frequency at 20 s after the addition of sample (F20s), and that of 400 s (F400s) was used to construct a calibration graph, and shortening of the assay time was achieved. The S. paratyphi A concentration
in the range of 105–109 cells/ml can be measured by this method.
Received: 9 May 1996/Revised: 6 September 1996/Accepted: 19 September 1996 相似文献
89.
The growth of cobalt hexacyanoferrate (CoHCF) films on bare and Au-colloid-modified electrodes in nitrate or sulfate solutions was monitored by electrochemical quartz crystal microbalance. The average efficiency of CoHCF film growth for Au colloid modified electrodes is 23 and 12 ng cm(-2) s(-1) in KNO3 and K2SO4 solutions, respectively, while those values for the bare gold electrode are 15 and 9 ng cm(-2) s(-1), respectively. In K2SO4 solution, the apparent molar masses for the Au-colloid-modified electrode at lower and higher potential is 58.4 and 37.3 g mol(-1), respectively, which is larger than those for the bare gold electrode (51.7 and 26.3 g mol(-1), respectively). The respective results were also obtained in KNO3 solution. Furthermore, the difference of the apparent molar masses at lower and higher potential for Au-colloid-modified electrodes is smaller than that for bare gold electrodes in the same electrolyte. Additionally, the mechanism of charge propagation is dependent on different anions in electrolyte solutions at higher potentials where the second redox reaction of CoHCF occurs. Therefore, the existence of Au colloids can accelerate CoHCF film growth and weaken the effect of anions on mass transport. 相似文献
90.
Photophysics of monodisperse platinum-acetylide oligomers: delocalization in the singlet and triplet excited states 总被引:1,自引:0,他引:1
Liu Y Jiang S Glusac K Powell DH Anderson DF Schanze KS 《Journal of the American Chemical Society》2002,124(42):12412-12413
A series of monodisperse Pt-acetylide polymers that contain the [-CC-(p-C6H4)-CC-(t-Pt(PBu3)2)-]n repeat unit has been prepared for n = 1, 2, 3, 4, 5, and 7. The photophysical properties of the series provide information concerning the relationship between the oligomer length and delocalization in the singlet and triplet excited states of the pi-conjugated electron system. The results imply that the singlet excited state is delocalized over approximately 6 repeat units; however, the triplet state is considerably more localized. The triplet energy is almost invariant with oligomer length, but the phosphorescence spectra and triplet nonradiative decay rates indicate that the electron-vibrational coupling in the triplet state decreases with increasing oligomer length. 相似文献