Zhengzhou, China
Zhengzhou, China

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Wu Q.,Guangzhou University | Guo K.,Guangzhou University | Liu G.,Guangzhou University | Wu J.-H.,Henan Institute of Education
Physica B: Condensed Matter | Year: 2013

Polaron effects on the linear and the nonlinear optical absorption coefficients and refractive index changes in cylindrical quantum dots with the radial parabolic potential and the z-direction linear potential with applied magnetic field are theoretically investigated. The optical absorption coefficients and refractive index changes are presented by using the compact-density-matrix approach and iterative method. Numerical calculations are presented for GaAs/AlGaAs. It is found that taking into account the electron-LO-phonon interaction, not only are the linear, the nonlinear and the total optical absorption coefficients and refractive index changes enhanced, but also the total optical absorption coefficients are more sensitive to the incident optical intensity. It is also found that no matter whether the electron-LO-phonon interaction is considered or not, the absorption coefficients and refractive index changes above are strongly dependent on the radial frequency, the magnetic field and the linear potential coefficient. © 2012 Elsevier B.V.


Liu G.,Guangzhou University | Guo K.,Guangzhou University | Wu Q.,Guangzhou University | Wu J.-H.,Henan Institute of Education
Superlattices and Microstructures | Year: 2013

Polaron effects on the optical rectification (OR) and the second harmonic generation (SHG) in cylindrical quantum dots (CQDs) with the radial parabolic potential and the z-direction linear potential in the presence of the magnetic field are theoretically investigated. The expressions for both the OR and the SHG are obtained within the framework of the compact-density-matrix approach and the iterative method. After considering the electron-LO-phonon interaction (ELOPI) as perturbation, the energy levels and the wave functions of an electron confined in CQD are obtained by perturbation theory. Numerical calculations are presented for GaAs/AlGaAs. It is found that when we consider the ELOPI, the resonant peak of the OR χ0(2) is enhanced, whereas the magnitude of the SHG χ2ω(2) is greatly enhanced. It is also found that when we ignore the ELOPI, with the increase of the radial confinement frequency ωρ and the magnetic field B, respectively, the resonant peak of the OR χ0(2) remains constant, whereas the magnitude of the SHG χ2ω(2) becomes small. However, when we consider the ELOPI, with the increase of ωρ,B and V respectively, both the resonant peak of the OR χ0(2) and the magnitude of the SHG χ2ω(2) become small. Our results also find that whether the ELOPI is considered or not, with the increase of ωρ,B and V, respectively, both χ0(2) and χ2ω(2) exhibit a blue shift. © 2012 Elsevier Ltd. All rights reserved.


Liu G.,Guangzhou University | Guo K.,Guangzhou University | Wu J.-H.,Henan Institute of Education
Superlattices and Microstructures | Year: 2013

Polaron effects on the optical rectification in cylindrical quantum dots (CQDs) with the radial parabolic potential plus the inverse squared potential and the z-direction semi-parabolic potential in the presence of electric and magnetic fields are theoretically investigated within the framework of the compact-density-matrix approach and iterative method. The energy levels and the wave functions of an electron are obtained by using the effective mass approximation. It is found that with polaron effects taken into account the optical rectification coefficients are greatly enhanced in both cases of with and without external electric field. © 2013 Elsevier Ltd. All rights reserved.


Wu J.,Henan Institute of Education | Guo K.,Guangzhou University | Liu G.,Guangzhou University
Physica B: Condensed Matter | Year: 2014

Polaron effects on nonlinear optical rectification in asymmetrical Gaussian potential quantum wells are studied by the effective mass approximation and the perturbation theory. The numerical results show that nonlinear optical rectification coefficients are strongly dependent on the barrier hight V 0 of the Gaussian potential quantum wells, the range L of the confinement potential and the electric field F. Besides, the numerical results show that no matter how V0, L and F change, taking into consideration polaron effects, the optical rectification coefficients χ0(2) get greatly enhanced. © 2014 Elsevier Ltd. All rights reserved.


Li H.-L.,Henan Institute of Education | Du Z.-N.,Yangzhou University | Wang G.-L.,Yangzhou University | Zhang Y.-C.,Yangzhou University
Materials Letters | Year: 2010

An eutectic NaCl-KCl molten salts method has been developed for the synthesis of SrTiO3 submicron crystallites and nanocrystals from SrO2 and two kinds (submicron and nano-sized) of TiO2 powders at 700 °C, which was much lower than that (generally > 1000 °C) of the conventional solid state reactions. The characterization results from X-ray diffraction and X-ray photoelectron spectroscopy revealed that the obtained products were pure perovskite phase SrTiO3 without any contamination of Na, K, and Cl ions. The scanning electronic microscopy and transmission electron microscopy images disclosed that the starting TiO2 played an important role in the morphology and size of the obtained SrTiO3: while the product derived from TiO2 submicron crystallites comprised faceted submicron crystallites of about 95-184 nm, that derived from TiO2 nanocrystals comprised quadrate nanocrystals of about 20-61 nm. Besides, based on the experiments without the molten NaCl-KCl eutectic, at different temperatures and times, and using different kinds of TiO2, the possible formation mechanism of SrTiO3 submicron crystallites and nanocrystals was proposed. © 2009 Elsevier B.V. All rights reserved.


Cao S.,Henan Institute of Education
Advanced Materials Research | Year: 2012

Through the analysis on the situation of water-saving in water supply and drainage system of our country, we recognize that there are still some problems in water-saving of buildings and we still have many works to do on water-saving. In order to build a water-saving society, and to save and protect water resources, we must improve our consciousness on water-saving, innovate water-saving technology, and promote the applications of water-saving equipments and facilities. © (2012) Trans Tech Publications, Switzerland.


Kang L.,Henan Institute of Education
Applied Mechanics and Materials | Year: 2014

K-means algorithm is a simple and efficient data mining clustering algorithm. For the current status of the bank card customer relationship management, based on data mining technology, design based on K-means clustering algorithm banking customer classification system. Data mining techniques can extract vast amounts of customer information data bank card implicit knowledge and spatial relationship model will represent the bank customers feature set of data objects automatically classified into each composed of clusters of similar objects, bank card customers in the banking system classification. This paper analyzes the existing spatial clustering methods summary and conclusion, based on the combined data bank card customers, according to the volatility of funds used to different customer groups, the use of K-means analysis to study characteristics of client groups, providing appropriate financial services. © (2014) Trans Tech Publications, Switzerland.


Peng L.,Henan Institute of Education
RISTI - Revista Iberica de Sistemas e Tecnologias de Informacao | Year: 2016

(reason) with the continuous development of information technology and the scale of the industry data, data processing technology continues to mature and gradually applied to the field of development. Data processing is a technology that is not trivial, implicit, unknown, and potentially valuable information from large scale data. With the development of the sports information industry, it has accumulated a large amount of data. The data processing and application in the field of sports field, especially the analysis of the data of the competitive sports competition will become a trend. (Method) this paper discusses the application of data processing in table tennis match, which is based on the study of the field knowledge and the technology of data processing. (Results) the statistical analysis system of the technical and tactical statistics of table tennis of match, and the analysis of the technique and tactics of table tennis match with computer. The problems caused by the main use of the manual are solved.


Xia L.-L.,Henan Institute of Education
Chinese Physics Letters | Year: 2011

A field integration method for a nonholonomic mechanical system of non-Chetaev's type is studied. The differential equations of the motion of the system are established. The solution of the corresponding holonomic system for the nonholonomic system is obtained by the field method. The restriction of nonholonomic constrained to initial conditions is added and the solution of the nonholonomic mechanical system of non-Chetaev's type is provided. An example is presented to illustrate the application of the results. © 2011 Chinese Physical Society and IOP Publishing Ltd.


Xia L.-L.,Henan Institute of Education | Cai J.-L.,Hangzhou Normal University
Chinese Physics B | Year: 2010

Conformal invariance and conserved quantities of a general holonomic system with variable mass are studied. The definition and the determining equation of conformal invariance for a general holonomic system with variable mass are provided. The conformal factor expression is deduced from conformal invariance and Lie symmetry. The relationship between the conformal invariance and the Lie symmetry is discussed, and the necessary and sufficient condition under which the conformal invariance would be the Lie symmetry of the system under an infinitesimal one-parameter transformation group is deduced. The conserved quantities of the system are given. An example is given to illustrate the application of the result. © 2010 Chinese Physical Society and IOP Publishing Ltd.

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