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Energy Spectra, g Factors and Their Pressure-Induced and/or Thermal Shifts of SrTiO3:Cr3+ and SrTiO3:Mn4+ Ⅲ: R-Line Thermal Shifts of SrTiO3:Mn4+

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Communications in Theoretical Physics 2001年第11期36卷 463-468页

作者： MA Dong-ping ZHANG ji-ping Department of Applied Physics Sichuan University Chengdu 610065 China International Centre for Materials Physics The Chinese Academy of Sciences Shenyang 110015 China Department of Applied Physics Sichuan University Chengdu 610065 China

By taking into account all the irreducible representations and their components in the electron-phonon interaction (EPI) as well as all the levels and the admixtures of basic wavefunctions within d3 electronic configuration,the values of the parameters in the expressions of thermal shift (TS) from EPI for the ground level, R level and R line of SrTiO3:Mn4+ have been evaluated; the R-line TS and various contributions to it have been calculated in the low-temperature region. It is found that all the three terms of R-line TS from EPI relevant to the lattice vibration are red shifts. The Raman term is the largest, the neighbor-level term is the second, and the optical-branch term is very small over the range of T ≤ 80 K. The contribution to R-line TS from thermal expansion has been approximately neglected in this work. The very strong EPI relevant to its lattice vibration for SrTiO3:Mn4+ causes its R-line TS to be an unusually large red-shift. Only by taking into account the strong softening of the low-frequency acoustic modes of the lattice vibration at low temperatures, can we successfully explain the variation of R-line TS of SrTiO3:Mn4+ with temperature.

关键词： crystal fields, optical properties, electron-phonon interaction, thermal shift, softening of acoustic modes

Resting Study of Tracer Experiment on Catalytic Wet Oxidation Reactor under Micro-gravity and Earth Gravity Conditions

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Chemical Research in Chinese Universities 2005年第6期21卷 702-706页

作者： YANG ji jiA jin-ping School of Environmental Science and Engineering Shanghai Jiaotong University Shanghai 200240 P. R. China

The International Space Station（ISS） employs catalytic wet oxidation carried out in a Volatile Reactor Assembly （VRA） for water recycling. Previous earth gravity experiments show that the VRA is very effective at removing polar, low molecular weight organics. To compare the reactor performance under micro-gravity and Earth gravity conditions, a tracer study was performed on a space shuttle in 1999 by using 0.2% potassium carbonate as the chemical tracer. In this paper, the experimental data were analyzed and it is indicated that the reactor can be considered as a plug flow one under both micro-gravity and earth gravity experimental conditions. It has also been proved that dispersion is not important in the VRA reactor under the experimental conditions. Tracer retardation was observed in the experiments and it is most likely caused by catalyst adsorption. It is concluded that the following reasons may also have influence on the retardation of mean residence time ：（1） the liquid can be held by appurtenances, which will retard the mean residence time; （2） the pores can hold the tracer, which can also retard the mean residence time.

关键词： Tracer study Micro-gravity Dispersion model Tank in series model Catalytic wet oxidation

DYNAMIC ADVANCED PLANNING AND SCHEDULING WITH FROZEN INTERVAL FOR NEW ORDERS

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Chinese Journal of Mechanical Engineering 2007年第4期20卷 117-119页

作者： CHEN Kejia ji ping Department of Industrial and Systems Engineering The Hong Kong Polytechnic University Hong Kong China

A dynamic advanced planning and scheduling （DAPS） problem is addressed where new orders arrive on a continuous basis. A periodic policy with frozen interval is adopted to increase stability on the shop floor. A genetic algorithm is developed to find a schedule at each rescheduling point for both original orders and new orders that both production idle time and penalties on tardiness and earliness of orders are minimized. The proposed methodology is tested on a small example to illustrate the effect of the frozen interval. The results indicate that the suggested approach can improve the schedule stability while retaining efficiency.

关键词： Dynamic advanced planning and scheduling Genetic algorithm Frozen interval

Controlling Thermal Conduction by Graded Materials

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Communications in Theoretical Physics 2018年第4期69卷 434-440页

作者： Qin ji ji-ping Huang Department of Physics State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (MOE) Fudan University Shanghai 200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093 China

Manipulating thermal conductivities are fundamentally important for controlling the conduction of heat at will. Thermal cloaks and concentrators, which have been extensively studied recently, are actually graded materials designed according to coordinate transformation approaches, and their effective thermal conductivity is equal to that of the host medium outside the cloak or concentrator. Here we attempt to investigate a more general problem: what is the effective thermal conductivity of graded materials? In particular, we perform a first-principles approach to the analytic exact results of effective thermal conductivities of materials possessing either power-law or linear gradation profiles. On the other hand, by solving Laplace's equation, we derive a differential equation for calculating the effective thermal conductivity of a material whose thermal conductivity varies along the radius with arbitrary gradation *** two methods agree with each other for both external and internal heat sources, as confirmed by simulation and experiment. This work provides different methods for designing new thermal metamaterials(including thermal cloaks and concentrators), in order to control or manipulate the transfer of heat.

关键词： thermal metamaterials graded materials effective thermal conductivity

Recent progress in econophysics： Chaos, leverage, and business cycles as revealed by agent-based modeling and human experiments

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Frontiers of physics 2017年第6期12卷 139-161页

作者： Chen Xin ji-ping Huang Department of Physics and State Key Laboratory of Surface Physics Fudan University Shanghai 200433 China

Agent-based modeling and controlled human experiments serve as two fundamental research methods in the field of econophysics. Agent-based modeling has been in development for over 20 years, but how to design virtual agents with high levels of human-like ＂intelligence＂ remains a challenge. On the other hand, experimental econophysics is an emerging field; however, there is a lack of experience and paradigms related to the field. Here, we review some of the most recent research results obtained through the use of these two methods concerning financial problems such as chaos, leverage, and business cycles. We also review the principles behind assessments of agents＇ intelligence levels, and some relevant designs for human experiments. The main theme of this review is to show that by combining theory, agent-based modeling, and controlled human experiments, one can garner more reliable and credible results on account of a better verification of theory; accordingly, this way, a wider range of economic and financial problems and phenomena can be studied.

关键词： agent-based modeling controlled human experiment minority game econophysics chaos,leverage business cycle

Robustness of critical points in a complex adaptive system： Effects of hedge behavior

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Frontiers of physics 2013年第4期8卷 461-466页

作者： Yuan Liang ji-ping Huang Department of Physics and State Key Laboratory of Surface Physics Fudan University Shanghai 200433 China Department of Physics College of Science Donghua University Shanghai 201602 China

In our recent papers, we have identified a class of phase transitions in the market-directed resource- allocation game, and found that there exists a critical point at which the phase transitions occur. The critical point is given by a certain resource ratio. Here, by performing computer simulations and theoretical analysis, we report that the critical point is robust against various kinds of human hedge behavior where the numbers of herds and contrarians can be varied widely. This means that the critical point can be independent of the total number of participants composed of normal agents, herds and contrarians, under some conditions. This finding means that the critical points we identified in this complex adaptive system （with adaptive agents） may also be an intensive quantity, similar to those revealed in traditional physical systems （with non-adaptive units）.

关键词： complex adaptive system phase transition resource allocation hedge behavior agent-based simulation

Theoretical Calculations of Optical Spectra and Their Pressure-Induced Shifts of MgAl_2O_4:Cr^(3+)

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Communications in Theoretical Physics 2008年第5期49卷 1339-1344页

作者： WU Fei ZHANG ji-ping College of Physical Science and Technology Sichuan University Chengdu 610065 China

The energy levels of spectrum, wavefunetions and crystal-field parameters of MgAl2O4：Cr^3＋ at normal pressure have been calculated by the means of diagonalizing the complete d^3 energy matrix （DCEM）. With these results, the g factor of the ground state at normal pressure and the pressure-induced shift （PS） of the spectra1 levels are also calculated uniformly, and the calculated results are all in good agreement with the experimental ones. And the contributions of various crystal-field parameters to the energy levels at normal pressure and the variational rates of the R1 line shifting with the pressure are calculated, from which the physical origin of the red shift of the R1 line shifting with increasing pressure have been clearly shown.

关键词： crystal fields energy spectrum g factor high-pressure effect

Calculation of Hugoniot properties for shocked nitromethane based on the improved Tsien's EOS

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Acta Mechanica Sinica 2010年第3期26卷 365-370页

作者： Bo Zhao ji-ping Cui jing Fan Key Laboratory of High Temperature Gas Dynamics Institute of Mechanics Chinese Academy of SciencesBeijing 100190 China

We have calculated the Hugoniot properties of shocked nitromethane based on the improved Tsien＇s equa- tion of state （EOS） that optimized by ＂exact＂ numerical molecular dynamic data at high temperatures and pressures. Comparison of the calculated results of the improved Tsien＇s EOS with the existed experimental data and the direct simu- lations show that the behavior of the improved Tsien＇s EOS is very good in many aspects. Because of its simple analytical form, the improved Tsien＇s EOS can be prospectively used to study the condensed explosive detonation coupling with chemical reaction.

关键词： Equation of state High pressures andtemperatures Shocked nitromethane Hugoniot properties

Theoretical Calculation of Energy Spectrum of YGG:Cr^(3+)and Thermal Shifts of Its R-Lines

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Communications in Theoretical Physics 2009年第5期51卷 914-918页

作者： YANG Kuo ZHANG ji-ping College of Physical Science and Technology Sichuan University Chengdu 610065 China Physical Department of A＇ba Teachers College Wenchuan 623000 China

With the strong-field scheme and trigonal bases, the complete d3 energy matrix in a trigonally distorted cubic-field has been constructed. By diagonalizing this matrix, the energy spectrum of YGG：Cr^3＋ at normal pressure and low temperature has been calculated. The g factor of the ground-state has been evaluated in terms of the energy spectrum. At the same time, by using the wavefunctions obtained from diagonalizing the complete d^3 energy matrix and Thermal Shifts theory, we calculate the thermal shifts of the sharp lines of YGG：Cr^3＋ and determine the relevant parameters. The calculated results are all in good agreement with the optical-spectrum and EPR experimental data. It is demonstrated that the obtained wavefunctions and the values of parameters are reasonable.

关键词： optical propenty electron-phonon interaction electronic structure thermal shift g factor