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We study the Lamb shift of a two-level atom arising from its coupling to the conformal massless scalar field, which satisfies the Dirichlet boundary conditions, in the Hartle-Hawking vacuum in the BTZ spacetime, and find that the Lamb shift in the BTZ spacetime is structurally similar to that of a uniformly accelerated atom near a perfectly reflecting boundary in (2+1)-dimensional flat spacetime. Our results show that the Lamb shift is suppressed in the BTZ spacetime as compared to that in the flat spacetime as long as the transition wavelength of the atom is much larger than $AdS$ radius of the BTZ spacetime while it can be either suppressed or enhanced if the transition wavelength of the atom is much less than $AdS$ radius. In contrast, the Lamb shift is always suppressed very close to the horizon of the BTZ spacetime and remarkably it reduces to that in the flat spacetime as the horizon is approached although the local temperature blows up there., Comment: 21 pages,2 figures

Charge batch planning is the bottleneck of production management planning in iron and steelmaking enterprises. The optimization of the charge batch planning process will directly influence the iron and steelmaking cost, production and energy consumption. In this paper, an effective mathematical model based on multi-objective weighting method is built up to describe the multi-performance indexes and the multi-constraints; an efficiency adaptive search algorithm based on linear augmented Lagrangian relaxation framework is proposed to alleviate the problem of sawtooth oscillation when the traditional Lagrangian algorithm searches within the feasible domain. The strategy proposed in this paper is verified based on the background of the actual steelmaking and continuous casting management process in China steelmaking plant. The optimization results guarantee the solution quality and speed of charge batch planning of steelmaking-continuous casting.

Steelmaking - continuous casting production scheduling is an important part of steelmaking production system. A scientific and reasonable steelmaking - continuous casting production scheduling is the key to improve the production efficiency of the steelmaking - continuous casting production system. In this paper, with the shortest total charge waiting time and the castings that are processed on time as the optimization goal, with the charges that are casted continuous within same casting and machine capacity constraints and so on as the constraints to established a mixed integer programming mathematical model. The augmented Lagrangian relaxation algorithm is used to solved the scheduling problem. The diagonal quadratic approximation method is used to linearize quadratic term so that it can be transformed into a problem to be solved with separable structure. Experiments show that the algorithm proposed has the advantages of fast convergence and short solution time for solving the steel-continuous casting scheduling problem compared to the traditional Lagrange algorithm, and the superiority is more obvious when the scale of the problem is increased.

Higher efficient degradation of methyl orange (MO) was demonstrated with nanometer-sized high-silica SAPO-5. By a hydrothermal process, synthesized high-silica SAPO-5 and low-silica SAPO-5 showed Si-to-Al ratios of 4.20 and 0.11, respectively. High-silica SAPO-5 showed much better MO degradation efficiency with a dosage of 70 mg in MO solution with a concentration of 10 mg/L under ultraviolet illumination. High-silica SAPO-5 also exhibited good producibility for preparation and stable photocatalytic activity even after the fifth recycling test. Optical characterizations of DRS, XPS, photocurrent density and time-resolved fluorescence were carried out for SAPO-5 samples. Finally, free radical and hole scavenging experiments were investigated for high-silica SAPO-5, and a MO photodegradation mechanism based on the charge transfer excited state of [Al2+–O−]* was proposed. This work highlights great prospects of high-silica SAPO-5 for organic pollutant removal with virtues of ideal efficiency and environmental friendliness.

This work considers the transportation time involved in ladle allocation during the steelmaking-continuous casting production. The optimisation problem of equipment allocation is presented, the optimal production sequence is determined and a schedule for charges is determined. In order to ensure that the operation time and the energy consumption are minimised, a solution methodology combining heuristic algorithm and conflict elimination algorithm is developed. The simulation experiment based on actual production data shows that this methodology can effectively solve the steelmaking and continuous casting scheduling problem. To validate the scheduling plan more intuitively and modify it further, we present an optimisation system based on unity 3D simulation platform. The system can effectively evaluate the optimisation of the solution and adjust the related data to modify the scheduling plan and ultimately get a reasonable rescheduling plan.