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921.
Wei Luo Xiang Kai Fu Li Hua Ma 《中国化学快报》2007,18(7):883-886
The high quality TiO2, MoO3-doped WO3 electrochromic film was prepared by the sol–gel method for the first time. The sol, which has hydrogen peroxide (H2O2) and oxalic acid (H2C2O4), was very stable at room temperature and quite suitable for the deposition of films. The WO3 electrochromic film prepared from this doped sol had excellent performance, such as short response time, no cracks, good adhesion to the substrate, high coloring efficiency and longevity of service. 相似文献
922.
Equations between the differential order and the maximum of the fractional-order differential for the specified peak signals are developed based on the variation of the maximum of the specified peak signals at different orders. Also, equations between the differential order and the zero-crossing of the fractional-order differential of the specified peak signals are proposed according to the variation of the zero-crossing of the specified peak signals at different orders. Characteristic paramters of the Gaus- sian peak, Lorentzian peak, and Tsallis peak can be estimated using estimator I and estimator II which are obtained by the equations above. As a result, a new method is presented to resolve the overlapped peaks signal. Firstly, a fractional-order differential of the specified peak signals is obtained with the fractional-order differentiation filter. Then, characteristic paramters of the specified peak signals can be extracted using estimator I and estimator II. Finally, the Tsallis peak is used as a model to assign the overlapping peak signals correctly. Experimental results show that the proposed method is efficient and effective for the simulated overlapping peaks and detected overlapping voltammetric peak signals. 相似文献
923.
To obtain new materials with synergetic or complementary behaviors, polyaniline composite filled with ZnO rods in ramification-like
structure was prepared by a hydrothermal approach. Comparative experiments of ZnO preparation in the presence of some metal
ions were also carried out. The results indicated that the morphology of ZnO was strongly affected by the preparation condition.
The method to grow ZnO rods in the presence of polyaniline offers a simple approach to obtain polyaniline composite filled
with linear ZnO structure. The results of X-ray photoelectron spectroscopy show that the strong interaction between ZnO and
polyaniline possibly exists to cause the charge transfer. 相似文献
924.
Han-Lang Wu Chen-Chi M. Ma Chia-Hsun Li Tzong-Ming Lee Chih-Yuan Chen Chin-Lung Chiang Chen Wu 《Journal of membrane science》2006,280(1-2):501-508
Poly(amide imide) (PAI) was synthesized using 1,2,4-benzenetricarboxylic anhydride (BTBA) and 4,4′-methylenebis(phenyl isocyanate) (MBPI). SPEEK/PAI blend membranes were prepared and investigated by NMR, GPC, FT-IR and AFM. The chemical structures of PAI and SPEEK were characterized by using NMR and FT-IR. The adsorption of the SPEEK/PAI blend membrane of water or methanol solution was also characterized. The significant swelling of the blend membrane in concentrated methanol solution was explained by the solubility parameter. The water diffusion coefficient (DH2O) was related to the lambda value of the membrane. The SPEEK/PAI blend membrane had a lower proton conductivity and methanol permeability than Nafion. However, the relative selectivity (proton conductivity divided by methanol permeability) of the SPEEK/PAI 70/30 (w/w) blend membrane was 3.46 × 104 S s cm−3, which is closed to that of Nafion (3.30 S s cm−3). 相似文献
925.
Chemical shifts of the alcohol and DMF protons in DMF–alcohol mixtures with the mole fraction of alcohol are reported in order to study the hydrogen bond interaction present in the mixtures. The densities of DMF–methanol mixture at 22°C are also measured. Excess volumes and excess chemical shifts are correlated by the Redlich–Kister equation. The relation between excess volumes and excess chemical shifts in the mixtures is discussed. It is found that the maximum excess chemical shifts E(CHO-OH) and E(CH3-OH) are positioned at about mole fraction methanol = 0.57 for the DMF–methanol system, as is V
E. The results show that the NMR spectral method offers a valuable approach to similar future studies of interactions in mixtures. 相似文献
926.
[reaction: see text] Reactions of alkylmercury chlorides with arene manganese tricarbonyl complexes in the presence of NaI led to the formation of the addition-reduction products. The mechanism was postulated to be the alkyl radical addition to ArMn(CO)3+ cation to form the corresponding 17 valence electron intermediate, which was then reduced by alkylmercury chloride via a singlet electron transfer process to afford the product and regenerate an alkyl radical. 相似文献
927.
The interaction of cyclodextrins with meso- Tetrakis (4-N-trimethylaminobenzyl) porphyrin (TAPP) in 0.1 mol l(-1) phosphate buffer (pH 7.0, 20 degrees C) has been studied by polarography. The TAPP can form the 1:1 inclusion complex with Sulfobutylether-beta-cyclodextrin (SBE-beta-CD) and1:2 inclusion complexes with other four cyclodextrins. A new expression, which is used to calculate the inclusion constant for1:2 inclusion complex by polarography, has been educed and testified firstly in this paper. Furthermore, the inclusion abilities of different kinds of cyclodextrins are compared. The result shows the inclusion ability of anionic cyclodextrin SBE-beta-CD with cationic porphyrin TAPP is very strong. It suggests that the charge attraction between CDs and TAPP plays an important role in the inclusion procedure except for the hydrophobic effect. The inclusion formation of anionic cyclodextrins with drugs can increase released rate of drugs at high pH; therefore, the suparmolecular data for the controlled release of the drugs that owned the similar properties as hematoporphyrin have been offered by polarography in this paper. 相似文献
928.
徐灿 《高等学校化学学报》1997,18(6):943-946
利用XeCl准分子激光烧蚀多种硅氧多孔结构材料,在负离子通道测得丰富的「(SiO2)nX」^-负离子团簇,并讨论了多孔网结构和表面活性基团的分布对激光能量的吸收,传输及团簇产生的重要作用。 相似文献
929.
930.
以Mg(NO3)2,Ca(NO3)2,Eu(NO3)3,Bi(NO3)3和Si(OC2H5)4为反应物,采用溶胶-凝胶法,在比较低的温度,首次合成0.701molMgO-0.175molCaO-1.25molSiO2:0.06molEu^3+,0.002molBi^3+(加入Li^+作为电荷补偿剂)发光体,得到了最佳合成条件,研究了由溶胶向凝胶转变和凝胶向发光晶体的转变过程,探讨了发光体在不同激光 相似文献