The Hopf algebraic structure, i. e. , comultiplication, coinverse and counit, is presented for a two-parameter deformed boson oscillator algebra. This result shows that the two-parameter deformed boson oscillator algebra is a Hopf algebra which is neither commutative nor cocommutative.

In this paper, we construct a type of coherent state with N components, and use it to span cycle representations of the Lie algebras SU(2), SU(1,l) and the Lit: superalgebra OSP( 1,2). The method for constructing cycle representation may be generalized to other Lie algebras and Lie superalgebras.

We have carried out a high precision torsion balance experiment in searching for abnormally large coherent scattering cross sections between a sapphire crystal and solar-neutrino. According to the hypothesis and the experimental results presented by J. Weber, a diurnal effect, which was 60 times larger than the noise level, should he observed obviously, but no significant diurnal effects were found at the level of 8.1 x 10^-8 dyn in our experiment.

We calculated the decay constant and radius of the pion in the framework of the Bethe-Salpeter equation with the vector-vector-type flat-bottom potential. The calculated results, f_π =102MeV and < r_π²>^1/2 =0.632fm, are close to experimental values of f_π = 93 MeV and < r_π²>^1/2 = 0.663± 0.023fm.

In the framework of relativistic quantum hadron dynamical theory, under semiclassical approximation and taking the vacuum fluctuation into account, a relativistic Vlasov equation (RVE) has been derived. Using RVE and considering other relativistic effects, we have studied the isovector dipole giant resonances built on ground state in spherical nuclei. The main results shown that the resonance energies for each multipole are larger than those obtained from the non-relativistic classical Vlasov approach. But by means of choosing a reasonable symmetry potential as 100MeV, the relativistic results can fit the experimental results very well.

High-energy γ-rays from the deexcitation of giant dipole resonance have been measured from the decay of compound nucleus ¹³²Ce^* formed by the ¹⁶O+¹¹⁶Sn reaction at an incident particle energy of 85.0MeV of ¹⁶O. The γ-ray multiplicity distribution of this reaction is calibrated with a multiplicity filter composed of 14 hexagonal BGO crystals. The shape evolution of the ¹³²Ce^* has been studied as a function of spin. The results reveal that the deformation parameter of prolate ¹³²Ce reduces when spin increases.

Multichannel quantum-defect theory is combined with the R-matrix calculations to study the resonance lineshape of autoionizing 3pns state of atomic magnesium. The R-matrices calculated with different reaction volumes hardly affect the total cross section of photoionization of the Mg 3sns Rydberg state. The comparison between theoretical and experimental results fs furnished.

A novel recipe is proposed to generate nonclassical vibrational states of the center-of mass motions of ions in a quantized trap, based on the quantum conversion between the quantum cavity fields and the quantized trap. It is shown that, when an ion trap system interacts with the eigen mode of a single-mode Fabry-Pérot cavity where the trap was set in, and a particularly selected external laser pulse through Raman transitions, the interchange of the quantum features between the quantum light states and the quantized trap states occurs. This kind of quantum conversion can be used to prepare some nonclassical trap states in an ion trap as well as to measure the properties of initial nonclassical vibrational states.

We have observed time-resolved spectra and spontaneous near-field profiles of vertical cavity surface-emitting laser, and have considered possible reasons for the origin of multiple transverse modes. The results show that, even under low-duty pulsed operation, the evolution of temperature profiles plays a dominant role in determing the transverse mode behaviour.

We have observed beating between two broadband light sources of linewidths 4.3 and 2.3nm by a method of time-delayed laser-induced double gratings. We explain the signal modulation by relating the signal intensity to the autocorrelation function of a field which consists of two frequency components.

Multifaceted asymmetric radiation from the edges (MARFEs) are studied on the basis of radiative condensation instability. The role of medium-Z impurity radiation and its association with the soft density limit are examined. A rigid poloidal rotation has been introduced which shows a bifurcation in the development of MARFE instability.

A relative spectroscopic method employing two spectral lines is developed to determine the radial temperature profile in an axisymmetric plasma discharge. The method is independent of the well-known Abel-inversion and of gas pressure if optically-thin lines are used, and also has no restriction on the presumption of the temperature profile such as the Bartels'approximation, i. e., the parabola. The high efficiency of the technique is tested by its application to a dielectric barrier gas discharge. The discharge configuration is an enclosed cylindrical and annular gap filled with Hg-Ar mixture.

A generalized functional variation theory of nematics is presented to take account of the local short range correlations between molecules. This theory is used to study nematics liquid crystal films. The nematics-isotropic transition temperature is determined. The orientational order parameter in each molecular layer and the internal energy per molecule associated with each layer are calculated. The numerical results are compared with those of the Monte Carlo simulation and of the mean field theory.

The critical temperatures of the Ising model in square and simple cubic lattices are derived with the variational-cumulant expansion approach to the seventh order. An extrapolating method is proposed to predict the critical temperature of infinite series according to the finite order expansion, at which a weighted fitting method is used. For the 2-dimensional Ising model, the critical temperature obtained by this method is in a deviation of 0.04% compared with the exact value, and the estimated results are robust for different order prediction. The critical temperature for the 3D Ising model is predicted as 4.490.

A generally exact theory for predicting the effective behavior of coupled linear-response for inhomogeneous media is developed. The theory can not only give the general results of the effective principal and coupled moduli for the coupled multifield problems, but also provide the interrelationships between these effective moduli. It can be directly employed to describe the coupled two-field or three-field response of any inhomogeneous media.

An experimental simulation using electrorheological (ER) fluid is developed to investigate the spatial configuration of the mitotic spindle. In the presence of two different kinds of electric field, the structures of particle arrangement in ER fluid are similar to the configuration of the mitotic spindle of the animal and plant cells respectively.

To explain the radio mechanism of non-relativistic jets, we investigate a nonlinear process in which ion-acoustic waves scatter into high frequency electromagnetic waves by the plasma having a non-Maxwell distribution with non-relativisical energetic electrons. The calculated reaults show that this mechanism is efficient, and may apply to the radiation of jets from active galaxies and radio bursts of sun flares.