In a four-level atomic system, we investigate the light pulse propagation properties interacting with only one laser field. It is shown that in the steady state, the group velocity of the light pulse can be changed fr...In a four-level atomic system, we investigate the light pulse propagation properties interacting with only one laser field. It is shown that in the steady state, the group velocity of the light pulse can be changed from subluminal to superluminal by varying the field detuning. Meanwhile, the effects of the field intensity on the group velocity are also shown. At last, with special parameters, the analytical solution for the group index is also obtained.展开更多
In this paper,we calculate the resolution of a photorefractive incoherent-to-coherent optical converter on the image plane for small diffraction efficiency by taking into account the optical imaging characteristics of...In this paper,we calculate the resolution of a photorefractive incoherent-to-coherent optical converter on the image plane for small diffraction efficiency by taking into account the optical imaging characteristics of the imaging lens.For a thin grating,we obtain a high resolution,which is comparable with the experimental results.展开更多
Efficiency and selectivity of hydrogenating depolymerization of the coal extract benzene-insoluble part over the heterogeneous Co–Mo/Al2O3 catalyst were assessed using a mathematical model. The analytical equations o...Efficiency and selectivity of hydrogenating depolymerization of the coal extract benzene-insoluble part over the heterogeneous Co–Mo/Al2O3 catalyst were assessed using a mathematical model. The analytical equations of the mathematical model were generated based on material balance incorporating the physico-chemical phenomena(reaction and diffusion) both in the autoclave and the catalyst grain. The equations offer the possibility for predicting changes of the reactants in the autoclave during the process and for determining the distribution of reactant concentrations in the grain as a function of its radius. The analytical equations of the model serve as the basis of the algorithm for assessing the influence of restrictive diffusion on the effectiveness and selectivity of the catalyst, and also for defining the optimal radii of the catalyst's pores to enable free transport of reactants in the grain interior.展开更多
This paper introduces to fluid state physics （fluid mechanics） a new interpretation of physical phenomena taking place in a fluid in motion. It introduces the base of a new theory claiming that every flow has its ow...This paper introduces to fluid state physics （fluid mechanics） a new interpretation of physical phenomena taking place in a fluid in motion. It introduces the base of a new theory claiming that every flow has its own internal structure of motion, which is definite organization of motion, rather than a ＂molecular chaos＂, known from the fluid statics. The paper introduces the new notion of structures vector fields of power and momentum and shows every Newtonian fluid flows are dual in character. It shows that the flow of Newtonian fluid has a dual character. It demonstrates on models and further in mathematical interpretation of physical phenomena. It introduces, on the one hand, the cycloidal motion model into the fluid mechanics, ad on the other hand an addition to the known, the classical model of Poiseuille laminar motion. The theory of dualism （double nature of physical phenomena） allows the description of selected characteristics of the flow, either by using the theory ofcycloidal motion （semicycloidal）, or by using the supplemented theory of laminar motion. The dualism theory is useful to describe each type of flows both, laminar and turbulent. This paper is only an introduction to the theory. It has been assigned number 1. It has been granted a high priority, since it contains basic concepts that will be used in others, following papers of long cycle.展开更多
The adsorption of isomaltotriose from aqueous solution on Ca2+ resin was investigated. The adsorption isotherm and the rate curve were determined. The pseudo-first-order model, pseudo-second-order model and the intrap...The adsorption of isomaltotriose from aqueous solution on Ca2+ resin was investigated. The adsorption isotherm and the rate curve were determined. The pseudo-first-order model, pseudo-second-order model and the intraparticle diffusion model were used to predict the rate constants of adsorption. The activation energy of adsorption has been also evaluated using the pseudo-second-order rate constants. The results showed that the adsorption of isomaltotriose onto Ca2+ resin is an exothermically activated process. The adsorption isotherm can be described by Langmuir equation. The pseudo-second-order model can fit well to the adsorption rate curve of isomaltotriose onto Ca2+ resin. It suggests that the adsorption of isomaltotriose onto Ca2+ resin involve chemical adsorption.展开更多
Based on the scaling idea of local slopes by Lopez et al. [Phys. Rev. Lett. 94 （2005） 166103], we investigate anomalous dynamic scaling of （d ＋ 1）-dimensional surface growth equations with spatially and temporall...Based on the scaling idea of local slopes by Lopez et al. [Phys. Rev. Lett. 94 （2005） 166103], we investigate anomalous dynamic scaling of （d ＋ 1）-dimensional surface growth equations with spatially and temporally correlated noise. The growth equations studied include the Kardar-Parisi-Zhang （KPZ）, Sun-Guo-Grant （SGG）, and Lai-Das Sarma-Villain （LDV） equations. The anomalous scaling exponents in both the weak- and strong-coupling regions are obtained, respectively.展开更多
We obtain the integrable relation for the one-dimensional nonlinear Schrodinger equations which describes the dynamics of a Bos-Einstein Condensates with time-dependent scattering length in a harmonic potential. The e...We obtain the integrable relation for the one-dimensional nonlinear Schrodinger equations which describes the dynamics of a Bos-Einstein Condensates with time-dependent scattering length in a harmonic potential. The exact one- and two-soliton solutions are constructed analytically by using the Hirota method. Then we further discuss the dynamics of the one soliton and the interactions between two solitons in currently experimental conditions.展开更多
The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aq...The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aqueous solution as a function of pH and ionic strength was studied by using batch technique combined with surface complexation model and density functional theory(DFT) calculations.The batch experimental results showed that the adsorption of 60Co(Ⅱ) was dependent on pH and independent of ionic strength,indicating the formation of inner-sphere surface complexes on TiO 2 surfaces.The results of surface complexation models and DFT calculations indicated that the surface species of 60Co(Ⅱ) adsorbed on TiO 2 followed the trend:B structure(i.e.,60Co(Ⅱ) was linked to one bridge oxygen site) was the dominant surface species at low pH,and TT structure(i.e.,60Co(Ⅱ) was linked to two terminal oxygen sites) became the important surface complex at neutral and alkaline pH values.These results demonstrated that a multi-technique approach could lead to definitive information on the structures of adsorbed 60Co(Ⅱ) at the molecular level at the TiO 2 /water interfaces,as well as realistic models to rationalize and accurately evaluate the macroscopic manifestations of radionuclide adsorption phenomena.展开更多
基金National Natural Science Foundation of China under Grant No.10547108the Natural Science Foundation of Foshan University
文摘In a four-level atomic system, we investigate the light pulse propagation properties interacting with only one laser field. It is shown that in the steady state, the group velocity of the light pulse can be changed from subluminal to superluminal by varying the field detuning. Meanwhile, the effects of the field intensity on the group velocity are also shown. At last, with special parameters, the analytical solution for the group index is also obtained.
文摘In this paper,we calculate the resolution of a photorefractive incoherent-to-coherent optical converter on the image plane for small diffraction efficiency by taking into account the optical imaging characteristics of the imaging lens.For a thin grating,we obtain a high resolution,which is comparable with the experimental results.
文摘Efficiency and selectivity of hydrogenating depolymerization of the coal extract benzene-insoluble part over the heterogeneous Co–Mo/Al2O3 catalyst were assessed using a mathematical model. The analytical equations of the mathematical model were generated based on material balance incorporating the physico-chemical phenomena(reaction and diffusion) both in the autoclave and the catalyst grain. The equations offer the possibility for predicting changes of the reactants in the autoclave during the process and for determining the distribution of reactant concentrations in the grain as a function of its radius. The analytical equations of the model serve as the basis of the algorithm for assessing the influence of restrictive diffusion on the effectiveness and selectivity of the catalyst, and also for defining the optimal radii of the catalyst's pores to enable free transport of reactants in the grain interior.
文摘This paper introduces to fluid state physics （fluid mechanics） a new interpretation of physical phenomena taking place in a fluid in motion. It introduces the base of a new theory claiming that every flow has its own internal structure of motion, which is definite organization of motion, rather than a ＂molecular chaos＂, known from the fluid statics. The paper introduces the new notion of structures vector fields of power and momentum and shows every Newtonian fluid flows are dual in character. It shows that the flow of Newtonian fluid has a dual character. It demonstrates on models and further in mathematical interpretation of physical phenomena. It introduces, on the one hand, the cycloidal motion model into the fluid mechanics, ad on the other hand an addition to the known, the classical model of Poiseuille laminar motion. The theory of dualism （double nature of physical phenomena） allows the description of selected characteristics of the flow, either by using the theory ofcycloidal motion （semicycloidal）, or by using the supplemented theory of laminar motion. The dualism theory is useful to describe each type of flows both, laminar and turbulent. This paper is only an introduction to the theory. It has been assigned number 1. It has been granted a high priority, since it contains basic concepts that will be used in others, following papers of long cycle.
基金Natural Science Foundation of Guangdong Province (5300563)
文摘The adsorption of isomaltotriose from aqueous solution on Ca2+ resin was investigated. The adsorption isotherm and the rate curve were determined. The pseudo-first-order model, pseudo-second-order model and the intraparticle diffusion model were used to predict the rate constants of adsorption. The activation energy of adsorption has been also evaluated using the pseudo-second-order rate constants. The results showed that the adsorption of isomaltotriose onto Ca2+ resin is an exothermically activated process. The adsorption isotherm can be described by Langmuir equation. The pseudo-second-order model can fit well to the adsorption rate curve of isomaltotriose onto Ca2+ resin. It suggests that the adsorption of isomaltotriose onto Ca2+ resin involve chemical adsorption.
基金National Natural Science Foundation of China under Grant No.10674177
文摘Based on the scaling idea of local slopes by Lopez et al. [Phys. Rev. Lett. 94 （2005） 166103], we investigate anomalous dynamic scaling of （d ＋ 1）-dimensional surface growth equations with spatially and temporally correlated noise. The growth equations studied include the Kardar-Parisi-Zhang （KPZ）, Sun-Guo-Grant （SGG）, and Lai-Das Sarma-Villain （LDV） equations. The anomalous scaling exponents in both the weak- and strong-coupling regions are obtained, respectively.
基金National Natural Science Foundation of China under Grant Nos.90406017,10740420252,and 60525417the National Key Basic Research Special Foundation of China under Grant Nos.2005CB724508 and 2006CB921400
文摘We obtain the integrable relation for the one-dimensional nonlinear Schrodinger equations which describes the dynamics of a Bos-Einstein Condensates with time-dependent scattering length in a harmonic potential. The exact one- and two-soliton solutions are constructed analytically by using the Hirota method. Then we further discuss the dynamics of the one soliton and the interactions between two solitons in currently experimental conditions.
基金Progress of Projects Supported by NSFCsupported by the National Basic Research Program of China (2011CB933700)the National Natural Science Foundation of China (20907055,20971126,21071147,91126020,21077107)
文摘The interaction between radionuclides and solid/water interfaces is important to understand the physicochemical processes of radionuclides in the natural environment.Herein,the interaction of 60Co(Ⅱ) with TiO 2 in aqueous solution as a function of pH and ionic strength was studied by using batch technique combined with surface complexation model and density functional theory(DFT) calculations.The batch experimental results showed that the adsorption of 60Co(Ⅱ) was dependent on pH and independent of ionic strength,indicating the formation of inner-sphere surface complexes on TiO 2 surfaces.The results of surface complexation models and DFT calculations indicated that the surface species of 60Co(Ⅱ) adsorbed on TiO 2 followed the trend:B structure(i.e.,60Co(Ⅱ) was linked to one bridge oxygen site) was the dominant surface species at low pH,and TT structure(i.e.,60Co(Ⅱ) was linked to two terminal oxygen sites) became the important surface complex at neutral and alkaline pH values.These results demonstrated that a multi-technique approach could lead to definitive information on the structures of adsorbed 60Co(Ⅱ) at the molecular level at the TiO 2 /water interfaces,as well as realistic models to rationalize and accurately evaluate the macroscopic manifestations of radionuclide adsorption phenomena.
