Both temperature dependence of polarizability and plasmon dispersion in unmagnetized metal (or semiconductor) electron gases are investigated in this paper. It is obtained that, with a continuous variation of temper...Both temperature dependence of polarizability and plasmon dispersion in unmagnetized metal (or semiconductor) electron gases are investigated in this paper. It is obtained that, with a continuous variation of temperature in a large region, the polarizability and dispersion change non-monotonously. The static polarizability X(q, w =0, μ, T) and dispersion wp(q, T) for finite T in three, two and one dimensional electron gases are calculated numerically. In addition, dispersion relation w(q) at a definite temperature (T ≠0) is similar to that at T = 0.展开更多
Assuming that the main variables in the life processes at the molecular level are the conforma- tion of biological macromolecules and their frontier electrons a formalism of quantum theory on conformation-electron sys...Assuming that the main variables in the life processes at the molecular level are the conforma- tion of biological macromolecules and their frontier electrons a formalism of quantum theory on conformation-electron system is proposed. Based on the quantum theory of conformation-electron system, the protein folding is regarded as a quantum transition between torsion states on polypep- tide chain, and the folding rate is calculated by nonadiabatic operator method. The rate calculation is generalized to the case of frequency variation in folding. An analytical form of protein folding rate formula is obtained, which can be served as a useful tool for further studying protein folding. The application of the rate theory to explain the protein folding experiments is briefly summarized. It includes the inertial moment dependence of folding rate, the unified description of two-state and multistate protein folding, the relationship of folding and unfolding rates versus denaturant concen- tration, the distinction between exergonic and endergonic foldings, the ultrafast and the downhill folding viewed from quantum folding theory, and, finally, the temperature dependence of folding rate and the interpretation of its non-Arrhenius behaviors. All these studies support the view that the protein folding is essentially a quantum transition between conformational states.展开更多
The phenomenological theory of ferroelectrics was developed by Landau-Devonshire about 70 years ago in the 1940s [1], and the celebrated theory has been very successful in analyzing ferroelectric phase transitions [2,...The phenomenological theory of ferroelectrics was developed by Landau-Devonshire about 70 years ago in the 1940s [1], and the celebrated theory has been very successful in analyzing ferroelectric phase transitions [2,3], domain structures [4], as well as strain engineering [5,6]. Recently, it has been demonstrated that it is also capable of capturing emerging polarization textures such as a ferroelectric vortex [7], proving its wide applicability not only at phenomenological level, but also at the atomic scale. The idea is simple, that the internal energy density of a ferroelectric depends on polarization, the order parameter, and upon the phase transition, the energy becomes degenerate, corresponding to multiple ferroelectric variants arising from broken symmetry. Such behavior is captured well by a polynomial of polarization with temperaturedependent coefficient, as Devonshire originally demonstrated for barium titanate [1].展开更多
基金supported by National Natural Science Foundation of China (No.10775055)
文摘Both temperature dependence of polarizability and plasmon dispersion in unmagnetized metal (or semiconductor) electron gases are investigated in this paper. It is obtained that, with a continuous variation of temperature in a large region, the polarizability and dispersion change non-monotonously. The static polarizability X(q, w =0, μ, T) and dispersion wp(q, T) for finite T in three, two and one dimensional electron gases are calculated numerically. In addition, dispersion relation w(q) at a definite temperature (T ≠0) is similar to that at T = 0.
基金supported by the National Key R&D Program of China(2019YFA0705104)partially sponsored by the General Research Fund under Project City U 11212920 and COCHE。
文摘Assuming that the main variables in the life processes at the molecular level are the conforma- tion of biological macromolecules and their frontier electrons a formalism of quantum theory on conformation-electron system is proposed. Based on the quantum theory of conformation-electron system, the protein folding is regarded as a quantum transition between torsion states on polypep- tide chain, and the folding rate is calculated by nonadiabatic operator method. The rate calculation is generalized to the case of frequency variation in folding. An analytical form of protein folding rate formula is obtained, which can be served as a useful tool for further studying protein folding. The application of the rate theory to explain the protein folding experiments is briefly summarized. It includes the inertial moment dependence of folding rate, the unified description of two-state and multistate protein folding, the relationship of folding and unfolding rates versus denaturant concen- tration, the distinction between exergonic and endergonic foldings, the ultrafast and the downhill folding viewed from quantum folding theory, and, finally, the temperature dependence of folding rate and the interpretation of its non-Arrhenius behaviors. All these studies support the view that the protein folding is essentially a quantum transition between conformational states.
基金supported by the National Natural Science Foundation of China(11572276 and 11772286)
文摘The phenomenological theory of ferroelectrics was developed by Landau-Devonshire about 70 years ago in the 1940s [1], and the celebrated theory has been very successful in analyzing ferroelectric phase transitions [2,3], domain structures [4], as well as strain engineering [5,6]. Recently, it has been demonstrated that it is also capable of capturing emerging polarization textures such as a ferroelectric vortex [7], proving its wide applicability not only at phenomenological level, but also at the atomic scale. The idea is simple, that the internal energy density of a ferroelectric depends on polarization, the order parameter, and upon the phase transition, the energy becomes degenerate, corresponding to multiple ferroelectric variants arising from broken symmetry. Such behavior is captured well by a polynomial of polarization with temperaturedependent coefficient, as Devonshire originally demonstrated for barium titanate [1].