It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this...It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this paper we propose a new inefficiency of the least squares estimator with the measure of generalized variance and obtain its bound.展开更多
Much interest has been devoted to organometallic NLO materials. We have become interested in exploring the utility of ferrocenyl group as the conjugating bridge. Thus, we synthesized 1-{{[1,3-(5-methylbenzo)dithiol]-2...Much interest has been devoted to organometallic NLO materials. We have become interested in exploring the utility of ferrocenyl group as the conjugating bridge. Thus, we synthesized 1-{{[1,3-(5-methylbenzo)dithiol]-2-yli- dene}methyl}-1’-[2-(p-nitrophenyl)-(E)-ethenyl]ferrocene (1). This new ferrocenyl compound has a donor and an acceptor group in 1,1’-positions. Investigations of the solvatochromic property of the compound revealed that it has polarized structure in a polar solvent, such as DMF. SHG efficiency of the compound was estimated by an SHEW (second-harmonic generation with the evanescent wave) method.展开更多
A new kind of polythiophene derivative, Poly(3-{2-[4-(2-ethylhexyloxy)-phenyl]-vinyl}-2,2′-bithiophene) (PTh), was applied in dye-sensitized solar cell to extend the light response of nanocrystalline TiO2 electrode. ...A new kind of polythiophene derivative, Poly(3-{2-[4-(2-ethylhexyloxy)-phenyl]-vinyl}-2,2′-bithiophene) (PTh), was applied in dye-sensitized solar cell to extend the light response of nanocrystalline TiO2 electrode. UV-vis absorption and fluorescence spectra were employed to investigate the interaction of PTh with nanocrystalline TiO2. The absorption coefficient of the PTh was high in visible part of spec- trum, and the fluorescence emission of the PTh can be efficiently quenched by TiO2 nanoparticles ow- ing to charge injection from the excited singlet state of PTh to the conduction band of the TiO2 particles. Cyclic voltammetry measurements were performed to study the dye regeneration reaction at the na- nocrystalline TiO2/electrolyte interface. The solar cell sensitized with PTh exhibited a short-circuit photocurrent (Isc) of 3.08 mA/cm2, an open circuit voltage (Voc) of 511 mV and an overall efficiency of 0.9% under the illumination of 100 mW/cm2 (AM 1.5).展开更多
文摘It was suggested by Pantanen that the mean squared error may be used to measure the inefficiency of the least squares estimator. Styan[2] and Rao[3] et al. discussed this inefficiency and it's bound later. In this paper we propose a new inefficiency of the least squares estimator with the measure of generalized variance and obtain its bound.
文摘Much interest has been devoted to organometallic NLO materials. We have become interested in exploring the utility of ferrocenyl group as the conjugating bridge. Thus, we synthesized 1-{{[1,3-(5-methylbenzo)dithiol]-2-yli- dene}methyl}-1’-[2-(p-nitrophenyl)-(E)-ethenyl]ferrocene (1). This new ferrocenyl compound has a donor and an acceptor group in 1,1’-positions. Investigations of the solvatochromic property of the compound revealed that it has polarized structure in a polar solvent, such as DMF. SHG efficiency of the compound was estimated by an SHEW (second-harmonic generation with the evanescent wave) method.
基金Supported by the Major State Basic Research Development Program of China (Grant No. 2006CB202605)High-Tech Research and Development of China Program (Grant No. 2007AA05Z439)+1 种基金National Natural Science Foundation of China (Grant No. 50221201)Innovative Foundation of the Center for Molecular Science, Chinese Academy of Sciences (Grant No. CMS-CX200718)
文摘A new kind of polythiophene derivative, Poly(3-{2-[4-(2-ethylhexyloxy)-phenyl]-vinyl}-2,2′-bithiophene) (PTh), was applied in dye-sensitized solar cell to extend the light response of nanocrystalline TiO2 electrode. UV-vis absorption and fluorescence spectra were employed to investigate the interaction of PTh with nanocrystalline TiO2. The absorption coefficient of the PTh was high in visible part of spec- trum, and the fluorescence emission of the PTh can be efficiently quenched by TiO2 nanoparticles ow- ing to charge injection from the excited singlet state of PTh to the conduction band of the TiO2 particles. Cyclic voltammetry measurements were performed to study the dye regeneration reaction at the na- nocrystalline TiO2/electrolyte interface. The solar cell sensitized with PTh exhibited a short-circuit photocurrent (Isc) of 3.08 mA/cm2, an open circuit voltage (Voc) of 511 mV and an overall efficiency of 0.9% under the illumination of 100 mW/cm2 (AM 1.5).
