A generalized scheme for the construction of coherent states in the context of position-dependent effective mass systems has been presented. This formalism is based on the ladder operators and associated algebra of th...A generalized scheme for the construction of coherent states in the context of position-dependent effective mass systems has been presented. This formalism is based on the ladder operators and associated algebra of the system which are obtained using the concepts of supersymmetric quantum mechanics and the property of shape invariance. In order to exemplify the general results and to analyze the properties of the coherent states, several examples have been considered.展开更多
In this paper, two novel semiclassical methods including the standard and supersymmetric WKB quantization conditions are suggested to discuss the Schroedinger equation with position-dependent effective mass. From a pr...In this paper, two novel semiclassical methods including the standard and supersymmetric WKB quantization conditions are suggested to discuss the Schroedinger equation with position-dependent effective mass. From a proper coordinate transformation, the formalism of the Schroedinger equation with position-dependent effective mass is mapped into isospectral one with constant mass and therefore for a given mass distribution and physical potential function the bound state energy spectrum can be determined easily by above method associated with a simple integral formula. It is shown that our method can give the analytical results for some exactly-solvable quantum systems.展开更多
A one-dimensional harmonic oscillator with position-dependent effective mass is studied. We quantize the oscillator to obtain a quantum Hamiltonian, which is manifestly Hermitian in configuration space, and the exact ...A one-dimensional harmonic oscillator with position-dependent effective mass is studied. We quantize the oscillator to obtain a quantum Hamiltonian, which is manifestly Hermitian in configuration space, and the exact solutions to the corresponding Schr¨odinger equation are obtained analytically in terms of modified Hermite polynomials.It is shown that the obtained solutions reduce to those of simple harmonic oscillator as the position dependence of the mass vanishes.展开更多
Using the coordinate transformation method, we solve the one-dimensional Schrodinger equation with position-dependent mass. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the sy...Using the coordinate transformation method, we solve the one-dimensional Schrodinger equation with position-dependent mass. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the systems are given. The eigenfunctions can be expressed in terms of the Jacobi, Hermite, and generalized Laguerre polynomials. All potentials for these solvable systems have an extra term Vm, which is produced from the dependence of mass on the position, compared with those for the systems of constant mass. The properties of Vm for several mass functions are discussed.展开更多
The properties of the 8-wave for a quasl-free partide with position-dependent mass （PDM） have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the fr...The properties of the 8-wave for a quasl-free partide with position-dependent mass （PDM） have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the free quantum particle around the origin only occurs in two dimensions, the quasi-free particle with PDM can experience attractive forces in D dimensions except D = 1 when its mass function satisfies some conditions. The effective mass of a particle varying with its position can induce effective interaction, which may be attractive in some cases. The analytical expressions of the eigenfunctions and the corresponding probability densities for the 8-waves of the two- and three-dimensional systems with a special PDM are given, and the existences of localization around the origin for these systems are shown.展开更多
We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. In order to inve...We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. In order to investigate the temporal evolution we first explore the statistical properties by means of weighting distribution and the Mandel parameter. It is found that the temporal evolution of the coherent states may exhibit the phenomena of quantum revivals and fractional revivals for a particular choice of position-dependent mass oscillator.展开更多
In this paper, on the basis of Huybrechts＇ strong-coupling polaron model, the Tokuda modified linearcombination operator method and the unitary transformation method are used to study the properties of the strongcoup...In this paper, on the basis of Huybrechts＇ strong-coupling polaron model, the Tokuda modified linearcombination operator method and the unitary transformation method are used to study the properties of the strongcoupling bound polaron considering the influence of Rashba effect, which is brought by the spin-orbit （SO） interaction, in the semiconductor triangular quantum well （TQW）. Numerical calculation on the RbCI TQW, as the example, is performed. The expressions for the effective mass of the polaron as a function of the vibration frequency, the velocity, the Coulomb bound potential and the electron areal density are derived. Numerical results show that the total effective mass of the polaron is composed of three parts. The interactions between the orbit and the spin with different directions have different effects on the effective mass of the bound polaron.展开更多
Known as a weak topological insulator(TI),BiSe structurally exhibits alternating stacks of quantum spin Hall bilayer("Bi_(2)")and three-dimensional TI layer("Bi_(2)Se_(3)").The low lattice thermal ...Known as a weak topological insulator(TI),BiSe structurally exhibits alternating stacks of quantum spin Hall bilayer("Bi_(2)")and three-dimensional TI layer("Bi_(2)Se_(3)").The low lattice thermal conductivity of BiSe due to the presence of Bi2 bilayers promises potentially good thermoelectric performance.Herein,the thermoelectric properties of nominal Bi_(1-x)Cu_(x)Se samples were studied as the functions of the content of Cu additive and temperature.It is found that Cu additives in BiSe(1)profoundly affect the texture of densified polycrystalline samples by inclining the crystallographic c-axis parallel toward the pressure direction in the densification process,(2)increase considerably the effective mass and thus the Seebeck coefficient,and(3)yield point defects and Cu-Se secondary phases that effectively scatter heat-carrying phonons.As a result,the optimized electrical and thermal properties yield a thermoelectric figure of merit of zT~0.29 in Bi_(1-x)Cu_(x)Se(x=0.03)sample at 467 K in parallel to the pressure direction and a zT~0.20 at 468 K in the perpendicular direction.展开更多
In this study,a harmonic oscillator with position-dependent mass is investigated.Firstly,as an introduction,we give a full description of the system by constructing its classical Lagrangian;thereupon,we derive the rel...In this study,a harmonic oscillator with position-dependent mass is investigated.Firstly,as an introduction,we give a full description of the system by constructing its classical Lagrangian;thereupon,we derive the related classical equations of motion such as the classical Euler–Lagrange equations.Secondly,we fractionalize the classical Lagrangian of the system,and then we obtain the corresponding fractional Euler–Lagrange equations(FELEs).As a final step,we give the numerical simulations corresponding to the FELEs within different fractional operators.Numerical results based on the Caputo and the Atangana-Baleanu-Caputo(ABC)fractional derivatives are given to verify the theoretical analysis.展开更多
During the hyperacute phase of intracerebral hemorrhage(ICH),the mass effect and blood components mechanically lead to brain damage and neurotoxicity.Our findings revealed that the mass effect and transferrin precipit...During the hyperacute phase of intracerebral hemorrhage(ICH),the mass effect and blood components mechanically lead to brain damage and neurotoxicity.Our findings revealed that the mass effect and transferrin precipitate neuronal oxidative stress and iron uptake,culminating in ferroptosis in neurons.M6A(N6-methyladenosine)modification,the most prevalent mRNA modification,plays a critical role in various cell death pathways.The Fto(fat mass and obesity-associated protein)demethylase has been implicated in numerous signaling pathways of neurological diseases by modulating m6A mRNA levels.Regulation of Fto protein levels in neurons effectively mitigated mass effect-induced neuronal ferroptosis.Applying nanopore direct RNA sequencing,we identified voltage-dependent anion channel 3(Vdac3)as a potential target associated with ferroptosis.Fto influenced neuronal ferroptosis by regulating the m6A methylation of Vdac3 mRNA.These findings elucidate the intricate interplay between Fto,Vdac3,m6A methylation,and ferroptosis in neurons during the hyperacute phase post-ICH and suggest novel therapeutic strategies for ICH.展开更多
Objective:To develop a rapid,cost effective RT-PCR method for the mass scale diagnosis of such diseases at the vireraia stage to find out the actual disease burden in that area.Methods:For this purpose,cases with the ...Objective:To develop a rapid,cost effective RT-PCR method for the mass scale diagnosis of such diseases at the vireraia stage to find out the actual disease burden in that area.Methods:For this purpose,cases with the history of only short febrile illness were considered.Thus 157 samples with the history of dengue/chikungunya like illness and only 58 samples with a history of acute encephalitis syndrome(AES)were selected.Results:Out of 157 samples,42 and 74 were detected as dengue and chikungunya,respectively and out of 58 AES cases only 23 could be detected as Japanese encephalitis by this RT-PCR method.Conclusions:This cost effective RT-PCR method can detect the total positive cases that remain undetected by EL1SA method.Moreover,this method is capable to detect the viral RNA from patients'sera even after the appearance of IgM antibody at one fifth costs as compared with the other commercially available kits.展开更多
We have proposed a pocket formula for mass attenuation coefficient(μ/ρ), mass energy absorption coefficient(μ_(en)/ρ), and effective atomic number(Z_(eff)) in different tissues of human organs. We have also assign...We have proposed a pocket formula for mass attenuation coefficient(μ/ρ), mass energy absorption coefficient(μ_(en)/ρ), and effective atomic number(Z_(eff)) in different tissues of human organs. We have also assigned a new chemical formula for all studied tissues based on their composition. We have introduced a new parameter called effective composition index(C_(eff)). Based on this, we have introduced a new method to compute the effective atomic number. The evaluated photon interaction parameters are graphically represented. The evaluated average, maximum,minimum, and standard deviations of effective atomic number are tabulated. The proposed formula produces a mass attenuation coefficient, mass energy absorption coefficient, and effective atomic number from their展开更多
Possessing inherently low thermal conductivity,BiSbSe_(3) is a promising thermoelectric material for medium temperature.Therefore,to substantially optimize the thermoelectric performance of BiSbSe_(3),researchers main...Possessing inherently low thermal conductivity,BiSbSe_(3) is a promising thermoelectric material for medium temperature.Therefore,to substantially optimize the thermoelectric performance of BiSbSe_(3),researchers mainly focus on the strategies to improve its electrical transport properties.Among these strongly coupled thermoelectric parameters,carrier concentration and effective mass are two intrinsic variables to decisively affect the electrical transport properties.In this work,Cl as a donor dopant is effective to provide extra electrons in n-type BiSbSe_(3),and the carrier concentration and effective mass can be well optimized simultaneously with increasing Cl content owing to the multiple conduction bands in BiSbSe_(3).What’s more,maximum weighted mobility~53 cm^(2)V^(-1)s^(-1)is obtained in Cl-doped BiSbSe_(3),which contributes to a largely enhanced power factor~4.8μW cm^(-1)K^(-2)at room temperature and outperforms other halogen-doped BiSbSe_(3) samples.Finally,combining the significantly enhanced power factor and maintained low thermal conductivity,a maximum ZT~1.0 is achieved in Cl-doped BiSbSe_(3) at 800 K.展开更多
Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvable onedimensional quantum systems with non-constant mass, involving their ordering ambiguities. This work extends the res...Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvable onedimensional quantum systems with non-constant mass, involving their ordering ambiguities. This work extends the results recently reported in the literature and clarifies the relation between physically acceptable effective mass Hamiltonians.展开更多
The ramifications of the effective mass splitting on the nuclear stopping and isospin tracer during heavy-ion collisions within the gigaelectron volt energy region are studied using an isospin-dependent quantum molecu...The ramifications of the effective mass splitting on the nuclear stopping and isospin tracer during heavy-ion collisions within the gigaelectron volt energy region are studied using an isospin-dependent quantum molecular dynamics model.Three isotope probes,i.e.,a proton,deuteron,and triton,are used to calculate the nuclear stopping.Compared to the mn*>mp*case,the mn*<mp*parameter results in a stronger stopping for protons but a weaker stopping for tritons.The calculations of the isospin tracer show that the mn*>mp*parameter results in a higher isospin mix than the mn*<mp*parameter.The rapidity and impact parameter dependences of the isospin tracer are also studied.A constraining of the effective mass splitting using the free nucleons with high rapidity and in a central rather than peripheral collision is suggested.展开更多
Using the coordinate transformation method, we study the polynomial solutions of the Schr6dinger equation with position-dependent mass （PDM）. The explicit expressions for the potentials, energy eigenvalues, and eige...Using the coordinate transformation method, we study the polynomial solutions of the Schr6dinger equation with position-dependent mass （PDM）. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the systems are given. The issues related to normalization of the wavefunetions and Hermiticity of the Hamiltonian are also analyzed.展开更多
The electronic structures, the effective masses, and optical properties of spinel CdCr_2S_4 are studied by using the fullpotential linearized augmented planewave method and a modified Becke–Johnson exchange functiona...The electronic structures, the effective masses, and optical properties of spinel CdCr_2S_4 are studied by using the fullpotential linearized augmented planewave method and a modified Becke–Johnson exchange functional within the densityfunctional theory. Most importantly, the effects of the spin–orbit coupling（SOC） on the electronic structures and carrier effective masses are investigated. The calculated band structure shows a direct band gap. The electronic effective mass and the hole effective mass are analytically determined by reproducing the calculated band structures near the BZ center.SOC substantially changes the valence band top and the hole effective masses. In addition, we calculated the corresponding optical properties of the spinel structure CdCr_2S_4. These should be useful to deeply understand spinel CdCr_2S_4 as a ferromagnetic semiconductor for possible semiconductor spintronic applications.展开更多
A new multivariate statistical strategy for analyzing large datasets that are produced by imaging mass spectrometry（IMS） techniques is reported.The strategy divides the whole datacube of the sample into several subs...A new multivariate statistical strategy for analyzing large datasets that are produced by imaging mass spectrometry（IMS） techniques is reported.The strategy divides the whole datacube of the sample into several subsets and analyses them one by one to obtain the results.Instead of analyzing the whole datacube at one time,the strategy makes the analysis easier and decreases the computation time greatly.In this report,the IMS data are produced by the air flow-assisted ionization IMS（AFAI-IMS）.The strategy can be used in combination with most multivariate statistical analysis methods.In this paper,the strategy was combined with the principal component analysis（PCA） and partial least square analysis（PLS）.It was proven to be effective by analyzing the handwriting sample.By using the strategy,the m/z corresponding to the specific lipids in rat brain tissue were distinguished successfully.Moreover the analysis time grew linearly instead of exponentially as the size of sample increased.The strategy developed in this study has enormous potential for searching for the mjz of potential biomarkers quickly and effectively.展开更多
Using ladder operators for the non-linear oscillator with position-dependent effective mass, realization of the dynamic group SU(1,1) is presented. Keeping in view the algebraic structure of the non-linear oscillator,...Using ladder operators for the non-linear oscillator with position-dependent effective mass, realization of the dynamic group SU(1,1) is presented. Keeping in view the algebraic structure of the non-linear oscillator, coherent states are constructed using Barut–Girardello formalism and their basic properties are discussed. Furthermore, the statistical properties of these states are investigated by means of Mandel parameter and second order correlation function. Moreover,it is shown that in the harmonic limit, all the results obtained for the non-linear oscillator with spatially varying mass reduce to corresponding results of the linear oscillator with constant mass.展开更多
Exactly Solvable Potentials (ESPs) of Position-Dependent Mass (PDM) Schrodinger equation are generated from Hulthen Potential (parent system) by using Extended Transformation (ET) method. The method includes a Co-ordi...Exactly Solvable Potentials (ESPs) of Position-Dependent Mass (PDM) Schrodinger equation are generated from Hulthen Potential (parent system) by using Extended Transformation (ET) method. The method includes a Co-ordinate Transformation (CT) followed by Functional Transformation (FT) of wave function. Mass function of parent system gets transformed to that of generated system. Two new ESPs are generated. The explicit expressions of mass functions, energy eigenvalues and corresponding wave functions for newly generated potentials (systems) are derived. System specific regrouping method is also discussed.展开更多
文摘A generalized scheme for the construction of coherent states in the context of position-dependent effective mass systems has been presented. This formalism is based on the ladder operators and associated algebra of the system which are obtained using the concepts of supersymmetric quantum mechanics and the property of shape invariance. In order to exemplify the general results and to analyze the properties of the coherent states, several examples have been considered.
基金The project supported by the Natural Science Foundation of Zhejiang Province of China under Grant No. Y605037 .
文摘In this paper, two novel semiclassical methods including the standard and supersymmetric WKB quantization conditions are suggested to discuss the Schroedinger equation with position-dependent effective mass. From a proper coordinate transformation, the formalism of the Schroedinger equation with position-dependent effective mass is mapped into isospectral one with constant mass and therefore for a given mass distribution and physical potential function the bound state energy spectrum can be determined easily by above method associated with a simple integral formula. It is shown that our method can give the analytical results for some exactly-solvable quantum systems.
文摘A one-dimensional harmonic oscillator with position-dependent effective mass is studied. We quantize the oscillator to obtain a quantum Hamiltonian, which is manifestly Hermitian in configuration space, and the exact solutions to the corresponding Schr¨odinger equation are obtained analytically in terms of modified Hermite polynomials.It is shown that the obtained solutions reduce to those of simple harmonic oscillator as the position dependence of the mass vanishes.
基金The project supported by National Natural Science Foundation of China for 0utstanding Young Scientists under Grant No. 10125521, the Doctoral Fund of the Ministry of Education under Grant No. 20010284036, the State Key Basic Research Development Program of China under Grant No. G2000077400, the Chinese Academy of Sciences Knowledge Innovation Project under Grant No. KJCX2-SW-N02, and National Natural Science Foundation of China under Grant No. 60371013
文摘Using the coordinate transformation method, we solve the one-dimensional Schrodinger equation with position-dependent mass. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the systems are given. The eigenfunctions can be expressed in terms of the Jacobi, Hermite, and generalized Laguerre polynomials. All potentials for these solvable systems have an extra term Vm, which is produced from the dependence of mass on the position, compared with those for the systems of constant mass. The properties of Vm for several mass functions are discussed.
基金The project supported by National Natural Science Foundation of China for Distinguished Young Scientists under Grant No. 10125521, the Doctoral Fund of Ministry of Education of China under Grant No. 20010284036, the State Key Basic Research Development Program under Grant No. G2000077400, the Knowledge Innovation Project of the Chinese Academy of Sciences under Grant No. KJCX2-SW-N02, and National Natural Science Foundation of China under Grant No. 60371013
文摘The properties of the 8-wave for a quasl-free partide with position-dependent mass （PDM） have been discussed in details. Differed from the system with constant mass in which the localization of the s-wave for the free quantum particle around the origin only occurs in two dimensions, the quasi-free particle with PDM can experience attractive forces in D dimensions except D = 1 when its mass function satisfies some conditions. The effective mass of a particle varying with its position can induce effective interaction, which may be attractive in some cases. The analytical expressions of the eigenfunctions and the corresponding probability densities for the 8-waves of the two- and three-dimensional systems with a special PDM are given, and the existences of localization around the origin for these systems are shown.
文摘We develop generalized coherent states for a class of nonlinear oscillators with position-dependent effective mass in the context of the Gazeau–Klauder formalism and discuss some of their properties. In order to investigate the temporal evolution we first explore the statistical properties by means of weighting distribution and the Mandel parameter. It is found that the temporal evolution of the coherent states may exhibit the phenomena of quantum revivals and fractional revivals for a particular choice of position-dependent mass oscillator.
基金National Natural Science Foundation of China under Grant No.10347004
文摘In this paper, on the basis of Huybrechts＇ strong-coupling polaron model, the Tokuda modified linearcombination operator method and the unitary transformation method are used to study the properties of the strongcoupling bound polaron considering the influence of Rashba effect, which is brought by the spin-orbit （SO） interaction, in the semiconductor triangular quantum well （TQW）. Numerical calculation on the RbCI TQW, as the example, is performed. The expressions for the effective mass of the polaron as a function of the vibration frequency, the velocity, the Coulomb bound potential and the electron areal density are derived. Numerical results show that the total effective mass of the polaron is composed of three parts. The interactions between the orbit and the spin with different directions have different effects on the effective mass of the bound polaron.
基金the Graduate Scientific Research and Innovation Foundation of Chongqing,China(No.CYB 19064)the National Natural Science Foundation of China(Nos.51772035,11674040,51472036 and 51672270)+4 种基金the Fundamental Research Funds for the Central Universities(No.106112017CDJQJ308821)the Key Research Program of Frontier Sciences,CAS(No.QYZDB-SSW-SLH016)the CSC Scholarship(No.201806050180)2019 ITS Summer Fellowship,the Natural Science Foundation of Chongqing,China(No.cstc2019jcyj-msxmX0554)the Starting Research Fund from Chongqing University。
文摘Known as a weak topological insulator(TI),BiSe structurally exhibits alternating stacks of quantum spin Hall bilayer("Bi_(2)")and three-dimensional TI layer("Bi_(2)Se_(3)").The low lattice thermal conductivity of BiSe due to the presence of Bi2 bilayers promises potentially good thermoelectric performance.Herein,the thermoelectric properties of nominal Bi_(1-x)Cu_(x)Se samples were studied as the functions of the content of Cu additive and temperature.It is found that Cu additives in BiSe(1)profoundly affect the texture of densified polycrystalline samples by inclining the crystallographic c-axis parallel toward the pressure direction in the densification process,(2)increase considerably the effective mass and thus the Seebeck coefficient,and(3)yield point defects and Cu-Se secondary phases that effectively scatter heat-carrying phonons.As a result,the optimized electrical and thermal properties yield a thermoelectric figure of merit of zT~0.29 in Bi_(1-x)Cu_(x)Se(x=0.03)sample at 467 K in parallel to the pressure direction and a zT~0.20 at 468 K in the perpendicular direction.
文摘In this study,a harmonic oscillator with position-dependent mass is investigated.Firstly,as an introduction,we give a full description of the system by constructing its classical Lagrangian;thereupon,we derive the related classical equations of motion such as the classical Euler–Lagrange equations.Secondly,we fractionalize the classical Lagrangian of the system,and then we obtain the corresponding fractional Euler–Lagrange equations(FELEs).As a final step,we give the numerical simulations corresponding to the FELEs within different fractional operators.Numerical results based on the Caputo and the Atangana-Baleanu-Caputo(ABC)fractional derivatives are given to verify the theoretical analysis.
基金supported by the National Key R&D Program of China(2022YFE0131000)the National Natural Science Foundation of China(82220108012,82271306,and 82071307)+1 种基金The Science and Education for Health Foundation of Suzhou for Youth(KJXW2023001)the Boxi Youth Natural Science Foundation(BXQN2023028).
文摘During the hyperacute phase of intracerebral hemorrhage(ICH),the mass effect and blood components mechanically lead to brain damage and neurotoxicity.Our findings revealed that the mass effect and transferrin precipitate neuronal oxidative stress and iron uptake,culminating in ferroptosis in neurons.M6A(N6-methyladenosine)modification,the most prevalent mRNA modification,plays a critical role in various cell death pathways.The Fto(fat mass and obesity-associated protein)demethylase has been implicated in numerous signaling pathways of neurological diseases by modulating m6A mRNA levels.Regulation of Fto protein levels in neurons effectively mitigated mass effect-induced neuronal ferroptosis.Applying nanopore direct RNA sequencing,we identified voltage-dependent anion channel 3(Vdac3)as a potential target associated with ferroptosis.Fto influenced neuronal ferroptosis by regulating the m6A methylation of Vdac3 mRNA.These findings elucidate the intricate interplay between Fto,Vdac3,m6A methylation,and ferroptosis in neurons during the hyperacute phase post-ICH and suggest novel therapeutic strategies for ICH.
基金supported by the Department of Science and Technology,Goverment of West Bengal.India[grant No.705(Sanc.)ST/P/S&T/9G-27/2007]
文摘Objective:To develop a rapid,cost effective RT-PCR method for the mass scale diagnosis of such diseases at the vireraia stage to find out the actual disease burden in that area.Methods:For this purpose,cases with the history of only short febrile illness were considered.Thus 157 samples with the history of dengue/chikungunya like illness and only 58 samples with a history of acute encephalitis syndrome(AES)were selected.Results:Out of 157 samples,42 and 74 were detected as dengue and chikungunya,respectively and out of 58 AES cases only 23 could be detected as Japanese encephalitis by this RT-PCR method.Conclusions:This cost effective RT-PCR method can detect the total positive cases that remain undetected by EL1SA method.Moreover,this method is capable to detect the viral RNA from patients'sera even after the appearance of IgM antibody at one fifth costs as compared with the other commercially available kits.
文摘We have proposed a pocket formula for mass attenuation coefficient(μ/ρ), mass energy absorption coefficient(μ_(en)/ρ), and effective atomic number(Z_(eff)) in different tissues of human organs. We have also assigned a new chemical formula for all studied tissues based on their composition. We have introduced a new parameter called effective composition index(C_(eff)). Based on this, we have introduced a new method to compute the effective atomic number. The evaluated photon interaction parameters are graphically represented. The evaluated average, maximum,minimum, and standard deviations of effective atomic number are tabulated. The proposed formula produces a mass attenuation coefficient, mass energy absorption coefficient, and effective atomic number from their
基金supported financially by the National Natural Science Foundation of China(Nos.51772012 and 51671015)the National Key Research and Development Program of China(Nos.2018YFB0703600 and 2018YFA0702100)+5 种基金the Beijing Natural Science Foundation(No.JQ18004)the Shenzhen Peacock Plan Team(No.KQTD2016022619565991)111 Project(No.B17002)financial support from Postdoctoral Science Foundation of China(No.2019M660399)the National Postdoctoral Program for Innovative Talents(No.BX20190028)support from the National Science Fund for Distinguished Young Scholars(No.51925101)。
文摘Possessing inherently low thermal conductivity,BiSbSe_(3) is a promising thermoelectric material for medium temperature.Therefore,to substantially optimize the thermoelectric performance of BiSbSe_(3),researchers mainly focus on the strategies to improve its electrical transport properties.Among these strongly coupled thermoelectric parameters,carrier concentration and effective mass are two intrinsic variables to decisively affect the electrical transport properties.In this work,Cl as a donor dopant is effective to provide extra electrons in n-type BiSbSe_(3),and the carrier concentration and effective mass can be well optimized simultaneously with increasing Cl content owing to the multiple conduction bands in BiSbSe_(3).What’s more,maximum weighted mobility~53 cm^(2)V^(-1)s^(-1)is obtained in Cl-doped BiSbSe_(3),which contributes to a largely enhanced power factor~4.8μW cm^(-1)K^(-2)at room temperature and outperforms other halogen-doped BiSbSe_(3) samples.Finally,combining the significantly enhanced power factor and maintained low thermal conductivity,a maximum ZT~1.0 is achieved in Cl-doped BiSbSe_(3) at 800 K.
文摘Within the frame of a novel treatment we make a complete mathematical analysis of exactly solvable onedimensional quantum systems with non-constant mass, involving their ordering ambiguities. This work extends the results recently reported in the literature and clarifies the relation between physically acceptable effective mass Hamiltonians.
基金the National Natural Science Foundation of China(Nos.11905018 and 11875328)the Scientific and Technological Innovation Programs of Higher Education Institutions of Shanxi Province,China(No.2019L0908)。
文摘The ramifications of the effective mass splitting on the nuclear stopping and isospin tracer during heavy-ion collisions within the gigaelectron volt energy region are studied using an isospin-dependent quantum molecular dynamics model.Three isotope probes,i.e.,a proton,deuteron,and triton,are used to calculate the nuclear stopping.Compared to the mn*>mp*case,the mn*<mp*parameter results in a stronger stopping for protons but a weaker stopping for tritons.The calculations of the isospin tracer show that the mn*>mp*parameter results in a higher isospin mix than the mn*<mp*parameter.The rapidity and impact parameter dependences of the isospin tracer are also studied.A constraining of the effective mass splitting using the free nucleons with high rapidity and in a central rather than peripheral collision is suggested.
文摘Using the coordinate transformation method, we study the polynomial solutions of the Schr6dinger equation with position-dependent mass （PDM）. The explicit expressions for the potentials, energy eigenvalues, and eigenfunctions of the systems are given. The issues related to normalization of the wavefunetions and Hermiticity of the Hamiltonian are also analyzed.
基金Project supported by the Joint Fund of the National Natural Science Foundation of Chinathe China Academy of Engineering Physics(Grant Nos.U1430117and U1230201)
文摘The electronic structures, the effective masses, and optical properties of spinel CdCr_2S_4 are studied by using the fullpotential linearized augmented planewave method and a modified Becke–Johnson exchange functional within the densityfunctional theory. Most importantly, the effects of the spin–orbit coupling（SOC） on the electronic structures and carrier effective masses are investigated. The calculated band structure shows a direct band gap. The electronic effective mass and the hole effective mass are analytically determined by reproducing the calculated band structures near the BZ center.SOC substantially changes the valence band top and the hole effective masses. In addition, we calculated the corresponding optical properties of the spinel structure CdCr_2S_4. These should be useful to deeply understand spinel CdCr_2S_4 as a ferromagnetic semiconductor for possible semiconductor spintronic applications.
基金supported by the National Instrumentation Programmme(Nos.2011YQ17006702 and 2011YQ14015010)the National Natural Science Foundation of China(Nos.81102413 and 21175121)Fundamental Research Program of Shenzhen (No.JC201005280634A).
文摘A new multivariate statistical strategy for analyzing large datasets that are produced by imaging mass spectrometry（IMS） techniques is reported.The strategy divides the whole datacube of the sample into several subsets and analyses them one by one to obtain the results.Instead of analyzing the whole datacube at one time,the strategy makes the analysis easier and decreases the computation time greatly.In this report,the IMS data are produced by the air flow-assisted ionization IMS（AFAI-IMS）.The strategy can be used in combination with most multivariate statistical analysis methods.In this paper,the strategy was combined with the principal component analysis（PCA） and partial least square analysis（PLS）.It was proven to be effective by analyzing the handwriting sample.By using the strategy,the m/z corresponding to the specific lipids in rat brain tissue were distinguished successfully.Moreover the analysis time grew linearly instead of exponentially as the size of sample increased.The strategy developed in this study has enormous potential for searching for the mjz of potential biomarkers quickly and effectively.
文摘Using ladder operators for the non-linear oscillator with position-dependent effective mass, realization of the dynamic group SU(1,1) is presented. Keeping in view the algebraic structure of the non-linear oscillator, coherent states are constructed using Barut–Girardello formalism and their basic properties are discussed. Furthermore, the statistical properties of these states are investigated by means of Mandel parameter and second order correlation function. Moreover,it is shown that in the harmonic limit, all the results obtained for the non-linear oscillator with spatially varying mass reduce to corresponding results of the linear oscillator with constant mass.
文摘Exactly Solvable Potentials (ESPs) of Position-Dependent Mass (PDM) Schrodinger equation are generated from Hulthen Potential (parent system) by using Extended Transformation (ET) method. The method includes a Co-ordinate Transformation (CT) followed by Functional Transformation (FT) of wave function. Mass function of parent system gets transformed to that of generated system. Two new ESPs are generated. The explicit expressions of mass functions, energy eigenvalues and corresponding wave functions for newly generated potentials (systems) are derived. System specific regrouping method is also discussed.
