The energy spectrum of the hydrogen atom has been applied in calculating the time rate of energy transitions between the quantum states of the atom. The formal basis of the approach has been provided by the quantum pr...The energy spectrum of the hydrogen atom has been applied in calculating the time rate of energy transitions between the quantum states of the atom. The formal basis of the approach has been provided by the quantum properties of energy and time deduced from the Joule-Lenz law. The rates of the energy transitions obtained in this way were compared with the quantum-mechanical probabilities of transitions calculated earlier by Bethe and Condon and Shortley for the same pairs of the quantum states.展开更多
The paper applies a one-to-one correspondence which exists between individual Schr?dinger perturbation terms and the diagrams obtained on a circular scale of time to whole sets of the Schr?dinger terms belonging to a ...The paper applies a one-to-one correspondence which exists between individual Schr?dinger perturbation terms and the diagrams obtained on a circular scale of time to whole sets of the Schr?dinger terms belonging to a definite perturbation order. In effect the diagram properties allowed us to derive the recurrence formulae giving the number of higher perturbative terms from the number of lower order terms. This recurrence formalism is based on a complementary property that any perturbation order N can be composed of two positive integer components Na , Nb combined into N in all possible ways. Another result concerns the degeneracy of the perturbative terms. This degeneracy is shown to be only twofold and the terms having it are easily detectable on the basis of a circular scale. An analysis of this type demonstrates that the degeneracy of the perturbative terms does not exist for very low perturbative orders. But when the perturbative order exceeds five, the number of degenerate terms predominates heavily over that of nondegenerate terms.展开更多
The Schrodinger perturbation energy for an arbitrary order N of the perturbation has been presented with the aid of a circular scale of time. The method is of a recurrent character and developed for a non-degenerate q...The Schrodinger perturbation energy for an arbitrary order N of the perturbation has been presented with the aid of a circular scale of time. The method is of a recurrent character and developed for a non-degenerate quantum state. It allows one to reduce the inflation of terms necessary to calculate known from the Feynman’s diagrammatical approach to a number below that applied in the original Schrodinger perturbation theory.展开更多
The low-energy mutual neutralization(MN)reactions Na^(+)+H^(-)→Na(nl)+H have been studied by employing the full quantum-mechanical molecular-orbital close-coupling(QMOCC)method over a wide energy range of 10^(-3)-10^...The low-energy mutual neutralization(MN)reactions Na^(+)+H^(-)→Na(nl)+H have been studied by employing the full quantum-mechanical molecular-orbital close-coupling(QMOCC)method over a wide energy range of 10^(-3)-10^(3) e V/u.Total and state-selective cross sections have been investigated and compared with the available theoretical and experimental data,and the state-selective rate coefficients for the temperature range of 100-10000 K have been obtained.In the present work,all the necessary highly excited states are included,and the influences of rotational couplings and 10 active electrons are considered.It is found that in the energy below 10 e V/u,the Na(4s)state is the most dominant exit state with a contribution of approximately 78%to the branch fraction,which is in best agreement with the experimental data.For energies above 10 e V/u,the MN total cross section is larger than those obtained in other theoretical calculations and shows a slow decreasing trend because the main exit states change,when the energy is above 100 e V/u,the dominant exit state becomes the Na(3p)state,while the Na(4s)state becomes the third most important exit state.The datasets presented in this paper,including the potential energy curve,the radial and rotational couplings,the total and state-selective cross sections,are openly available at https://doi.org/10.57760/sciencedb.j00113.00112.展开更多
We investigate the entanglement in the interacting system of a single mode thermal field and a single qubit with dissipation in the dispersive limit. The influence of initial temperature of thermal field and atoms on ...We investigate the entanglement in the interacting system of a single mode thermal field and a single qubit with dissipation in the dispersive limit. The influence of initial temperature of thermal field and atoms on the entanglement is then examined.展开更多
We investigate several Hamiltonians for a free particle in a one-dimensional box, in the context of supersymmetric quantum mechanics. Specifically, we study this problem with the Neumann boundary condition, the period...We investigate several Hamiltonians for a free particle in a one-dimensional box, in the context of supersymmetric quantum mechanics. Specifically, we study this problem with the Neumann boundary condition, the periodic and antiperiodic boundary condition, and some mixed and complex boundary conditions. This is achieved by using an approach recently proposed which expresses the factorization of the partner Hamiltonians in terms of the probability density and current for the ground-state eigenfunction of one of them.展开更多
A Fock-Darwin system in noncommutative quantum mechanics is studied. By constructing Heisenberg algebra we obtain the levels on noncommutative space and noncommutative phase space, and give the corrections to the resu...A Fock-Darwin system in noncommutative quantum mechanics is studied. By constructing Heisenberg algebra we obtain the levels on noncommutative space and noncommutative phase space, and give the corrections to the results in usual quantum mechanics. Moreover, to search the difference among the three spaces, the degeneracy is analysed by two ways, the value of ω/ωe and certain algebra realization (SU(2)and SU(1,1)), and some interesting properties in the magnetic field limit are exhibited, such as totally different degeneracy and magic number distribution for the given frequency or mass of a system in strong magnetic field.展开更多
Quantum aspects of the Joule-Lenz law for the transmission of energy allowed us to calculate the time rate of energy transitions between the quantum states of the hydrogen atom in a fully non-probabilistic way. The ca...Quantum aspects of the Joule-Lenz law for the transmission of energy allowed us to calculate the time rate of energy transitions between the quantum states of the hydrogen atom in a fully non-probabilistic way. The calculation has been extended to all transitions between p and s states having main quantum numbers not exceeding 6. An evident similarity between the intensity pattern obtained from the Joule-Lenz law and the corresponding quantum-mechanical transition pro-babilities has been shown.展开更多
The purpose of this study was to develop a physico-mathematical model and technique for estimation of chemical bond stability depending on electric field intensity of an external point charge.A hypothesis for a possib...The purpose of this study was to develop a physico-mathematical model and technique for estimation of chemical bond stability depending on electric field intensity of an external point charge.A hypothesis for a possible physico-chemical mechanism of the formation of additional harmful gases in the rock destruction by blasting was proposed.The theoretical basis of the hypothesis is the method of theretical evaluation of bond energy depending on the distance to a point charge,the third Coulomb centre.The quantum-mechanical model for calculating the electronic terms of molecules makes it possible to solve problems associated with the determination of parameters of molecules under the action of various physical fields on the system under consideration.The model was approved for some diatomic molecules.The discrepancy between the experimental data and calculated data did not exceed 14%,which proves accuracy of the obtained results.The model can be used in the field of research into the causes of gas-dynamic phenomena in underground coal mines,in studies of the degree of stability of nanostructured components of coal under physical influences,and in the theoretical design of new compounds and structures in the field of nanomaterial science and nanotechnology.展开更多
A monocyclopentadienyl titanium complex containing 8-quinolinolato (QCpTiCl_2) was synthesized. Its activities in ethylene polymerization at various Al/Ti molar ratios, different temperatures and activation time were ...A monocyclopentadienyl titanium complex containing 8-quinolinolato (QCpTiCl_2) was synthesized. Its activities in ethylene polymerization at various Al/Ti molar ratios, different temperatures and activation time were investigated. The activity with a Al/Ti molar ratio of 500 exhibited a maximum of 2.8×10~5 g/(mol.h) at 30℃. The activation time of QCpTiCl_2 with MAO before polymerization also plays a role on the activity. The structural properties of the produced polyethylene (molecular weight, molecular weight distribution and melting point) were discussed. Kinetic behaviors of ethylene polymerization with the QCpTiCl_2/MAO system at different Al/Ti molar ratios were studied. For the QCpTiMeCl/MAO system and the CpTiMe_2Cl/MAO system, binding energies of the examined intermediates were calculated by quantum-mechanical method based on ADF program, respectively. It is confirmed that the chlorinebridged adduct formed by the reaction of QCpTiMeCl with MAO is thermodynamically steady. In the case of the QCpTiMeCl/MAO system, olefin-separated ion pair (OSIP) mechanism is much favorable than ion-pair dissociation (IPD) mechanism. The experimental result on the CpTiMe_2Cl/MAO system showed lower activity for ethylene polymerization than that on the QCpTiMeCl/MAO system, which revealed that the CpTiMe_2Cl/MAO system is unfavorable to form active species with ethylene.展开更多
The electron excitation processes of H(1s)+He(1s^(2))→H(2s/2p)+He(1s^(2))are studied in impact energy range of 20-2000 e V/u by using the quantum-mechanical molecular orbital close-coupling(QMOCC)method.Total and sta...The electron excitation processes of H(1s)+He(1s^(2))→H(2s/2p)+He(1s^(2))are studied in impact energy range of 20-2000 e V/u by using the quantum-mechanical molecular orbital close-coupling(QMOCC)method.Total and state-selective cross sections have been obtained and compared with the available theoretical and experimental results.The results agree well with available measurements in the overlapping energy regions overall.The comparison of our results with other theoretical calculations further demonstrates the importance of considering a sufficient number of channels.The datasets presented in this paper,including the excitation cross sections,are openly available at https://www.doi.org/10.57760/sciencedb.j00113.00083.展开更多
We investigate the quantum-mechanical effects on the electrical properties of the double-gate j unction- less field effect transistors. The quantum-mechanical effect, or carrier energy-quantization effects on the thre...We investigate the quantum-mechanical effects on the electrical properties of the double-gate j unction- less field effect transistors. The quantum-mechanical effect, or carrier energy-quantization effects on the threshold voltage, of DG-JLFET are analytically modeled and incorporated in the Duarte et al. model and then verified by TCAD simulation.展开更多
We propose a quantum-mechanical Brayton engine model that works between two superposed states,employing a single particle confined in an arbitrary power-law trap as the working substance. Applying the superposition pr...We propose a quantum-mechanical Brayton engine model that works between two superposed states,employing a single particle confined in an arbitrary power-law trap as the working substance. Applying the superposition principle,we obtain the explicit expressions of the power and efficiency,and find that the efficiency at maximum power is bounded from above by the function: η+= θ/(θ+1),with θ being a potential-dependent exponent.展开更多
DNA autoionization is a fundamental process wherein ultraviolet (UV)- photoexcited nucleobases dissipate energy by charge transfer to the environment without undergoing chemical damage. Here, single-wall carbon nano...DNA autoionization is a fundamental process wherein ultraviolet (UV)- photoexcited nucleobases dissipate energy by charge transfer to the environment without undergoing chemical damage. Here, single-wall carbon nanotubes (SWNT) are explored as a photoluminescent reporter for the study of the mechanism and rates of DNA autoionization. Two-color photoluminescence spectroscopy allows separate photoexcitation of the DNA and the SWNTs in the UV and visible range, respectively. A strong SWNT photoluminescence quenching is observed when the UV pump is resonant with the DNA absorption, consistent with charge transfer from the excited states of the DNA to the SWNT. Semiempirical calculations of the DNA-SWNT electronic structure, combined with a Green's function theory for charge transfer, show a 20 fs autoionization rate, dominated by hole transfer. Rate-equation analysis of the spectroscopy data confirms that the quenching rate is limited by thermalization of the free charge carriers transferred to the nanotube reservoir. This approach has great potential for monitoring DNA excitation, autoionization, and chemical damage, both in vivo and in vitro.展开更多
文摘The energy spectrum of the hydrogen atom has been applied in calculating the time rate of energy transitions between the quantum states of the atom. The formal basis of the approach has been provided by the quantum properties of energy and time deduced from the Joule-Lenz law. The rates of the energy transitions obtained in this way were compared with the quantum-mechanical probabilities of transitions calculated earlier by Bethe and Condon and Shortley for the same pairs of the quantum states.
文摘The paper applies a one-to-one correspondence which exists between individual Schr?dinger perturbation terms and the diagrams obtained on a circular scale of time to whole sets of the Schr?dinger terms belonging to a definite perturbation order. In effect the diagram properties allowed us to derive the recurrence formulae giving the number of higher perturbative terms from the number of lower order terms. This recurrence formalism is based on a complementary property that any perturbation order N can be composed of two positive integer components Na , Nb combined into N in all possible ways. Another result concerns the degeneracy of the perturbative terms. This degeneracy is shown to be only twofold and the terms having it are easily detectable on the basis of a circular scale. An analysis of this type demonstrates that the degeneracy of the perturbative terms does not exist for very low perturbative orders. But when the perturbative order exceeds five, the number of degenerate terms predominates heavily over that of nondegenerate terms.
文摘The Schrodinger perturbation energy for an arbitrary order N of the perturbation has been presented with the aid of a circular scale of time. The method is of a recurrent character and developed for a non-degenerate quantum state. It allows one to reduce the inflation of terms necessary to calculate known from the Feynman’s diagrammatical approach to a number below that applied in the original Schrodinger perturbation theory.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.12204288,11934004,and 12203106)。
文摘The low-energy mutual neutralization(MN)reactions Na^(+)+H^(-)→Na(nl)+H have been studied by employing the full quantum-mechanical molecular-orbital close-coupling(QMOCC)method over a wide energy range of 10^(-3)-10^(3) e V/u.Total and state-selective cross sections have been investigated and compared with the available theoretical and experimental data,and the state-selective rate coefficients for the temperature range of 100-10000 K have been obtained.In the present work,all the necessary highly excited states are included,and the influences of rotational couplings and 10 active electrons are considered.It is found that in the energy below 10 e V/u,the Na(4s)state is the most dominant exit state with a contribution of approximately 78%to the branch fraction,which is in best agreement with the experimental data.For energies above 10 e V/u,the MN total cross section is larger than those obtained in other theoretical calculations and shows a slow decreasing trend because the main exit states change,when the energy is above 100 e V/u,the dominant exit state becomes the Na(3p)state,while the Na(4s)state becomes the third most important exit state.The datasets presented in this paper,including the potential energy curve,the radial and rotational couplings,the total and state-selective cross sections,are openly available at https://doi.org/10.57760/sciencedb.j00113.00112.
文摘We investigate the entanglement in the interacting system of a single mode thermal field and a single qubit with dissipation in the dispersive limit. The influence of initial temperature of thermal field and atoms on the entanglement is then examined.
文摘We investigate several Hamiltonians for a free particle in a one-dimensional box, in the context of supersymmetric quantum mechanics. Specifically, we study this problem with the Neumann boundary condition, the periodic and antiperiodic boundary condition, and some mixed and complex boundary conditions. This is achieved by using an approach recently proposed which expresses the factorization of the partner Hamiltonians in terms of the probability density and current for the ground-state eigenfunction of one of them.
基金Supported by the National Natural Science Foundation of China under Grant No 10575026, and the Natural Science Foundation of Zhejiang Provence under Grant No Y607437.
文摘A Fock-Darwin system in noncommutative quantum mechanics is studied. By constructing Heisenberg algebra we obtain the levels on noncommutative space and noncommutative phase space, and give the corrections to the results in usual quantum mechanics. Moreover, to search the difference among the three spaces, the degeneracy is analysed by two ways, the value of ω/ωe and certain algebra realization (SU(2)and SU(1,1)), and some interesting properties in the magnetic field limit are exhibited, such as totally different degeneracy and magic number distribution for the given frequency or mass of a system in strong magnetic field.
文摘Quantum aspects of the Joule-Lenz law for the transmission of energy allowed us to calculate the time rate of energy transitions between the quantum states of the hydrogen atom in a fully non-probabilistic way. The calculation has been extended to all transitions between p and s states having main quantum numbers not exceeding 6. An evident similarity between the intensity pattern obtained from the Joule-Lenz law and the corresponding quantum-mechanical transition pro-babilities has been shown.
基金The studies were accomplished within the framework of the project"Investigation of coal nanostructure as a source of coal mine methane"with a financial support of the Ministry of Education and Science of Ukraine according to the Order No.199 of February 10,2017.
文摘The purpose of this study was to develop a physico-mathematical model and technique for estimation of chemical bond stability depending on electric field intensity of an external point charge.A hypothesis for a possible physico-chemical mechanism of the formation of additional harmful gases in the rock destruction by blasting was proposed.The theoretical basis of the hypothesis is the method of theretical evaluation of bond energy depending on the distance to a point charge,the third Coulomb centre.The quantum-mechanical model for calculating the electronic terms of molecules makes it possible to solve problems associated with the determination of parameters of molecules under the action of various physical fields on the system under consideration.The model was approved for some diatomic molecules.The discrepancy between the experimental data and calculated data did not exceed 14%,which proves accuracy of the obtained results.The model can be used in the field of research into the causes of gas-dynamic phenomena in underground coal mines,in studies of the degree of stability of nanostructured components of coal under physical influences,and in the theoretical design of new compounds and structures in the field of nanomaterial science and nanotechnology.
基金The work is sub sidized by Special Funds for Major State Basis Research Projects of China(No.G1999064801)
文摘A monocyclopentadienyl titanium complex containing 8-quinolinolato (QCpTiCl_2) was synthesized. Its activities in ethylene polymerization at various Al/Ti molar ratios, different temperatures and activation time were investigated. The activity with a Al/Ti molar ratio of 500 exhibited a maximum of 2.8×10~5 g/(mol.h) at 30℃. The activation time of QCpTiCl_2 with MAO before polymerization also plays a role on the activity. The structural properties of the produced polyethylene (molecular weight, molecular weight distribution and melting point) were discussed. Kinetic behaviors of ethylene polymerization with the QCpTiCl_2/MAO system at different Al/Ti molar ratios were studied. For the QCpTiMeCl/MAO system and the CpTiMe_2Cl/MAO system, binding energies of the examined intermediates were calculated by quantum-mechanical method based on ADF program, respectively. It is confirmed that the chlorinebridged adduct formed by the reaction of QCpTiMeCl with MAO is thermodynamically steady. In the case of the QCpTiMeCl/MAO system, olefin-separated ion pair (OSIP) mechanism is much favorable than ion-pair dissociation (IPD) mechanism. The experimental result on the CpTiMe_2Cl/MAO system showed lower activity for ethylene polymerization than that on the QCpTiMeCl/MAO system, which revealed that the CpTiMe_2Cl/MAO system is unfavorable to form active species with ethylene.
基金supported by the National Natural Science Foundation of China(Grant Nos.12204288,11934004,and 12274040)
文摘The electron excitation processes of H(1s)+He(1s^(2))→H(2s/2p)+He(1s^(2))are studied in impact energy range of 20-2000 e V/u by using the quantum-mechanical molecular orbital close-coupling(QMOCC)method.Total and state-selective cross sections have been obtained and compared with the available theoretical and experimental results.The results agree well with available measurements in the overlapping energy regions overall.The comparison of our results with other theoretical calculations further demonstrates the importance of considering a sufficient number of channels.The datasets presented in this paper,including the excitation cross sections,are openly available at https://www.doi.org/10.57760/sciencedb.j00113.00083.
文摘We investigate the quantum-mechanical effects on the electrical properties of the double-gate j unction- less field effect transistors. The quantum-mechanical effect, or carrier energy-quantization effects on the threshold voltage, of DG-JLFET are analytically modeled and incorporated in the Duarte et al. model and then verified by TCAD simulation.
基金Supported by the National Natural Science Foundation of China under Grant Nos.1150509111265010+1 种基金and 11365015the Jiangxi Provincial Natural Science Foundation under Grant No.20132BAB212009
文摘We propose a quantum-mechanical Brayton engine model that works between two superposed states,employing a single particle confined in an arbitrary power-law trap as the working substance. Applying the superposition principle,we obtain the explicit expressions of the power and efficiency,and find that the efficiency at maximum power is bounded from above by the function: η+= θ/(θ+1),with θ being a potential-dependent exponent.
基金T. I. and S. V. R. acknowledge support by National Science Foundation (Nos. ECCS-1202398 and ECCS- 1509786) P. S. acknowledges REU NSF (No. PHY- 1359195). A. B. acknowledges the startup fund support from the University of Central Florida. The authors gratefully acknowledge access to facilities at the National Institute of Standards and Technology for PL measurements and the computational time support from the UCF Advanced Research Computing Center STOKES. We are thankful to Dr. J. Fagan as the host at NIST, Dr. J. Reimers for providing us with the CNDO code, and Dr. D. Roxbury for providing the MD trajectory.
文摘DNA autoionization is a fundamental process wherein ultraviolet (UV)- photoexcited nucleobases dissipate energy by charge transfer to the environment without undergoing chemical damage. Here, single-wall carbon nanotubes (SWNT) are explored as a photoluminescent reporter for the study of the mechanism and rates of DNA autoionization. Two-color photoluminescence spectroscopy allows separate photoexcitation of the DNA and the SWNTs in the UV and visible range, respectively. A strong SWNT photoluminescence quenching is observed when the UV pump is resonant with the DNA absorption, consistent with charge transfer from the excited states of the DNA to the SWNT. Semiempirical calculations of the DNA-SWNT electronic structure, combined with a Green's function theory for charge transfer, show a 20 fs autoionization rate, dominated by hole transfer. Rate-equation analysis of the spectroscopy data confirms that the quenching rate is limited by thermalization of the free charge carriers transferred to the nanotube reservoir. This approach has great potential for monitoring DNA excitation, autoionization, and chemical damage, both in vivo and in vitro.