CIRC is short for Cooperative Integrated Reading and Composition.It is to help improve students' English proficiency by integrating writing into reading.In order to verify the results of the method,the author made...CIRC is short for Cooperative Integrated Reading and Composition.It is to help improve students' English proficiency by integrating writing into reading.In order to verify the results of the method,the author made an experimental study in Nanning College for Vocational Technology.She designed a small teaching cycle of "7 phases with 12 steps"and applied CIRC in her English class.One of the results is that CIRC can improve students'academic achievements.展开更多
A Lagrangian tracer model is set up for Hangzhou Bay based on Coupled Hydrodynamical Ecological model for Regional Shelf Sea (COHERENS). The study area is divided into eight subdomains to identify the dominant physica...A Lagrangian tracer model is set up for Hangzhou Bay based on Coupled Hydrodynamical Ecological model for Regional Shelf Sea (COHERENS). The study area is divided into eight subdomains to identify the dominant physical processes, and the studied periods are March (the dry season) and July (the wet season). The model performance has been first verified by sea-surface elevation and tidal current observations at several stations. Eight tracer experiments are designed and Lagrangian particle tracking is simulated to examine the impact of physical processes (tide, wind and river runoff) on the transport of passive tracer released within the surface layer. Numerical simulations and analysis indicate that: (1) wind does not change the tracer distribution after 30 days except for those released from the south area of the bay during the wet season; (2) the tide and the Qiantang River runoff are important for particle transport in the head area of the bay; (3) the Changjiang River runoff affects the tracer transport at the mouth of the bay, and its impact is smaller in the dry season than in the wet season.展开更多
In the blossoming field of Cd-free semiconductor quantum dots(QDs),ternary Ⅰ-Ⅲ-VI QDs have received increasing attention due to the ease of the environmentally friendly synthesis of high-quality materials in water,t...In the blossoming field of Cd-free semiconductor quantum dots(QDs),ternary Ⅰ-Ⅲ-VI QDs have received increasing attention due to the ease of the environmentally friendly synthesis of high-quality materials in water,their high photoluminescence(PL)quantum yields(QYs)in the red and near infrared(NIR)region,and their inherently low toxicity.Moreover,their oxygen-insensitive long PL lifetimes of up to several hundreds of nanoseconds close a gap for applications exploiting the compound-specific parameter PL lifetime.To overcome the lack of reproducible synthetic methodologies and to enable a design-based control of their PL properties,we assessed and modelled the synthesis of high-quality MPA-capped AglnS2/ZnS(AlS/ZnS)QDs.Systematically refined parameters included reaction time,temperature,Ag:In ratio,S:In ratio,Zn:In ratio,MPA:ln ratio,and pH using a design-of-experiment approach.Guidance for the optimization was provided by mathematical models developed for the application-relevant PL parameters,maximum PL wavelength,QY,and PL lifetime as well as the elemental composition in terms of Ag:ln:Zn ratio.With these experimental data-based models,MPA:ln and Ag:ln ratios and pH values were identified as the most important synthesis parameters for PL control and an insight into the connection of these parameters could be gained.Subsequently,the experimental conditions to synthetize QDs with tunable emission and high QY were predicted.The excellent agreement between the predicted and experimentally found PL features confirmed the reliability of our methodology for the rational design of high quality AlS/ZnS QDs with defined PL features.This approach can be straightforwardly extended to other ternary and quaternary QDs and to doped QDs.展开更多
Dividend taxation is an important component of investors' taxes and has attracted the attention of policymakers and financial economists.However,the theory of dividends and the reform of dividend taxation remain a...Dividend taxation is an important component of investors' taxes and has attracted the attention of policymakers and financial economists.However,the theory of dividends and the reform of dividend taxation remain a puzzle.This paper analyzes the effect of dividend taxation on firms' dividend policies.Using a natural experiment and differencein-difference estimation,we find that China's dividend tax cut in 2005 led firms to increase their dividend payments.Companies with higher proportions of tradable individual shares or investment fund shares were more likely to increase their dividend payments.However,opportunistic behavior also exists,where companies with higher proportions of shares held by executives were also more likely to increase their dividend payments.These findings support the existence of a causal relationship between China's tax cut and firms' increased dividend payments and imply that the reform of dividend taxation in 2005 achieved its goal.展开更多
The acoustic signal from an impulsive source near an ideal rigid wedge consists of the reflected waves from the inclined plane and the diffracted waves from the apex of the wedge. There are two theoretical solutions o...The acoustic signal from an impulsive source near an ideal rigid wedge consists of the reflected waves from the inclined plane and the diffracted waves from the apex of the wedge. There are two theoretical solutions of the problem. The first was obtained by Biot-Tolstoy using normal coordinates. The second was Trorey's Helmholtz-Kirchhoff solution. So far the experimental measurements have concentrated on the diffracted wave from the wedge apex and ignored the rest of the solution. The Biot-Tolstoy exact wedge solution is used in this paper to study the sound transmission in wedges of angle 12 °and 52 °approximately. The theory and the experiments are consistent. Also studied is the behaviour of the reflected and diffracted waves from a 270 °wedge. Both theories predicted the existence a specular ' image ' reflection when a coincident source and receiver are over a half plane. The experimental results showed that the Biot-Tolstoy theory was accurate and the Trorey solution produced quite large errors.展开更多
文摘CIRC is short for Cooperative Integrated Reading and Composition.It is to help improve students' English proficiency by integrating writing into reading.In order to verify the results of the method,the author made an experimental study in Nanning College for Vocational Technology.She designed a small teaching cycle of "7 phases with 12 steps"and applied CIRC in her English class.One of the results is that CIRC can improve students'academic achievements.
基金Supported by the Natural Science Foundation of China (No.40576080)National High Technology Research and Development Program of China (863 Program, No. 2007AA12Z182)
文摘A Lagrangian tracer model is set up for Hangzhou Bay based on Coupled Hydrodynamical Ecological model for Regional Shelf Sea (COHERENS). The study area is divided into eight subdomains to identify the dominant physical processes, and the studied periods are March (the dry season) and July (the wet season). The model performance has been first verified by sea-surface elevation and tidal current observations at several stations. Eight tracer experiments are designed and Lagrangian particle tracking is simulated to examine the impact of physical processes (tide, wind and river runoff) on the transport of passive tracer released within the surface layer. Numerical simulations and analysis indicate that: (1) wind does not change the tracer distribution after 30 days except for those released from the south area of the bay during the wet season; (2) the tide and the Qiantang River runoff are important for particle transport in the head area of the bay; (3) the Changjiang River runoff affects the tracer transport at the mouth of the bay, and its impact is smaller in the dry season than in the wet season.
基金This work received financial support from the European Union(FEDER funds POCI/01/0145/FEDER/007265)National Funds(FCT/MEC,Fundacao para a Ciencia e Tecnologia and Ministerio da Educacao e Ciencia)under the Partnership Agreement PT2020 UID/QUI/50006/2013 and through the FCT PhD Programmes and by Programa Operacional Potencial Humano(POCH)+2 种基金specifically by the BiotechHealth Programme(Doctoral Programme on Cellular and Molecular Biotechnology Applied to Health Sciences),reference PD/00016/2012.J.X.S.thanks FCT and POPH for his PhD grant(SFRH/BD/98105/2013)K.D.W.acknowledges the European Unions Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement No.846764URG gratefully acknowledges financial support by the German Research Council(DFG,grant RE1203/12-3).
文摘In the blossoming field of Cd-free semiconductor quantum dots(QDs),ternary Ⅰ-Ⅲ-VI QDs have received increasing attention due to the ease of the environmentally friendly synthesis of high-quality materials in water,their high photoluminescence(PL)quantum yields(QYs)in the red and near infrared(NIR)region,and their inherently low toxicity.Moreover,their oxygen-insensitive long PL lifetimes of up to several hundreds of nanoseconds close a gap for applications exploiting the compound-specific parameter PL lifetime.To overcome the lack of reproducible synthetic methodologies and to enable a design-based control of their PL properties,we assessed and modelled the synthesis of high-quality MPA-capped AglnS2/ZnS(AlS/ZnS)QDs.Systematically refined parameters included reaction time,temperature,Ag:In ratio,S:In ratio,Zn:In ratio,MPA:ln ratio,and pH using a design-of-experiment approach.Guidance for the optimization was provided by mathematical models developed for the application-relevant PL parameters,maximum PL wavelength,QY,and PL lifetime as well as the elemental composition in terms of Ag:ln:Zn ratio.With these experimental data-based models,MPA:ln and Ag:ln ratios and pH values were identified as the most important synthesis parameters for PL control and an insight into the connection of these parameters could be gained.Subsequently,the experimental conditions to synthetize QDs with tunable emission and high QY were predicted.The excellent agreement between the predicted and experimentally found PL features confirmed the reliability of our methodology for the rational design of high quality AlS/ZnS QDs with defined PL features.This approach can be straightforwardly extended to other ternary and quaternary QDs and to doped QDs.
基金supported by the MOE Project of Humanities and Social Sciences(08JA630007)the National Natural Science Foundation of China(Approval No.71172029)
文摘Dividend taxation is an important component of investors' taxes and has attracted the attention of policymakers and financial economists.However,the theory of dividends and the reform of dividend taxation remain a puzzle.This paper analyzes the effect of dividend taxation on firms' dividend policies.Using a natural experiment and differencein-difference estimation,we find that China's dividend tax cut in 2005 led firms to increase their dividend payments.Companies with higher proportions of tradable individual shares or investment fund shares were more likely to increase their dividend payments.However,opportunistic behavior also exists,where companies with higher proportions of shares held by executives were also more likely to increase their dividend payments.These findings support the existence of a causal relationship between China's tax cut and firms' increased dividend payments and imply that the reform of dividend taxation in 2005 achieved its goal.
文摘The acoustic signal from an impulsive source near an ideal rigid wedge consists of the reflected waves from the inclined plane and the diffracted waves from the apex of the wedge. There are two theoretical solutions of the problem. The first was obtained by Biot-Tolstoy using normal coordinates. The second was Trorey's Helmholtz-Kirchhoff solution. So far the experimental measurements have concentrated on the diffracted wave from the wedge apex and ignored the rest of the solution. The Biot-Tolstoy exact wedge solution is used in this paper to study the sound transmission in wedges of angle 12 °and 52 °approximately. The theory and the experiments are consistent. Also studied is the behaviour of the reflected and diffracted waves from a 270 °wedge. Both theories predicted the existence a specular ' image ' reflection when a coincident source and receiver are over a half plane. The experimental results showed that the Biot-Tolstoy theory was accurate and the Trorey solution produced quite large errors.
