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The heavy ion fusion–evaporation reaction study for the high-spin spectroscopy of 75As has been performed via the reaction channel 70Zn(9Be, 1p3n)75As at a beam energy of 42 MeV. The collective structure especially a dipole band in 75As is established for the first time. The properties of this dipole band are investigated in terms of the self-consistent tilted axis cranking covariant density functional theory. Based on the theoretical description and the examination of the angular momentum components, this dipole band can be interpreted as a novel stapler band, where the valence neutrons in ( 1 g 9 / 2 ) orbital rather than the collective core are responsible for the closing of the stapler of angular momentum.

Excited states of the odd–odd nucleus 74 As have been investigated via heavy ion fusion evaporation reaction Zn 70 ( Li 7 , 3 n ) As 74 at beam energy of 30 MeV. The properties of the positive- and the negative- parity bands can be interpreted in terms of the Cranked Nilsson–Strutinsky (CNS) model calculations which show that the observed bands are built on the triaxial deformed shape. The inversion of the favored and unfavored signature branches observed in the positive-parity bands presents at high spins rather than normal signature inversion occurs at low spins. This phenomenon may be explained as the origin of unpaired band crossing in a highly rotating triaxial nucleus.

The tubular solid oxide fuel cell (SOFC) stack has important parameters that need to be identified and optimized for the control of high performance. In this paper, a simple SOFC electrochemical model which its parameters need to be optimized is introduced to implement stack control for high output power. A dynamic SOFC model is built based on three sub-models to provide a large numbers simulated data and different condition for optimization. Unlike the traditional parameter optimization method--simple genetic algorithm (SGA), an improved genetic algorithm (IGA) is introduced. The proposed method shows more accuracy and validity by comparing the different results using SGA and IGA methods, the simulated data, and experimental data. The models and IGA method are adapted to control processes.

In this article, based on least square estimation, a recursive algorithm for indirect learning structure predistorter is introduced. Simulation results show that of all polynomial predistorter nonlinear terms, higher-order (higher than 7th-order) nonlinear terms are so minor that they can be omitted in practical predistorter design. So, it is unnecessary to construct predistorter with higher-order polynomials, and the algorithm will always be stable. Further results show that even when 15th-order polynomial model is used, the algorithm is convergent after 10 iterations, and it can improve out-band spectrum of 20 MHz bandwidth signal by 64 dB, with a 1.2×10 11 matrix condition number.

Ion dynamics in non-perfect quadrupole traps differ from those in a pure quadrupole field. We obtain an analytic expression for a quadrupole field superimposed with weak, higher-order multipole fields. Single ion dynamics in such trapping fields close to the instability point are investigated. We show that for an in-phase octopole field, oscillating envelopes of the axial displacement grow exponentially with the parameter deviation; whereas for an out-of-phase octopole field the growth of the oscillating envelopes follows a square-root law. A hard-sphere scattering model is assumed to incorporate collisions with buffer-gas molecules. The collision frequency and cross-section are defined. A simulation algorithm for many-ion dynamics is developed based on the Verlet algorithm and Monte Carlo techniques. We show how a weak octopole field affects the mass resolution in a significant way.

A lattice-gas cellular automaton model for CO oxidation on metal surfaces is developed. The model treats the dynamics of the absorbed CO and O species explicitly and incorporates the effects of surface phase transformations through simple cellular automaton rules. Nucleation and growth processes are observed and studied. Oscillations associated with surface spatial structure are also obtained when surface phase transformations are possible. The model can serve as a basis for more detailed studies of the reactive dynamics of such systems.

On the basis of our previous study on barrier-crossing dynamics in a symmetric double-well potential, we investigate fast rate processes corresponding to barrier-crossing dynamics in an arbitrary asymmetric double-minimum potential. The evolution of the rate kernels is determined by a projected Fokker—Planck operator and its spectral properties are studied. This work provides a deeper insight into the nature of fast chemical interconversions.

We study the barrier-crossing rate processes described by the Bhatnagar—Gross—Krook (BGK) equation in the small barrier regime. The spectral properties of the rate kernels are investigated through a projected BGK equation and the chemical relaxation and characteristic microscopic times are obtained.

The time dependence of the rate kernels that determine the barrier crossing rates of a double-well system with Bhatnagar—Gross—Krook (BGK) dynamics is studied. The rate kernels evolve according to projected dynamics where that part of the evolution which is proportional to the species population numbers is removed. The rate kernels for projected and ordinary dynamics are compared for various values of the chemical and internal relaxation times, and the validity of a phenomenological rate law description is discussed.