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The spatial distribution of power facilities is uneven, thereby making the topology of geographical wiring diagrams (GWDs) based on the actual coordinates unclear. A single-line diagram has the adv...

The liquid-phase, catalytic oxidation of toluene with air in a continuous stirred tank reactor has become the main technology for producing benzoic acid. Designs are aimed at obtaining high product conversion rates but the reaction is strongly exothermic and therefore it is also important to maintain stable operation to guarantee product quality. However, there is currently no suitable process simulation model available for study. In this paper, a mathematical model of the reaction system is established and validated by comparison to literature data. Steady-state variables were calculated for a series of the operating conditions, using the homotopy continuation method, revealing the existence of multiple steady-state solutions. Two steady-state solutions were found for each operating condition, which had different conversion rates and sensitivities to changes in operating conditions. The operating point having the highest conversion rate was the most sensitive to changes in operating conditions, thus requiring a superior control system. A trade off must be carried out between conversion rate and production stability. Consequently, in practice, a number of factors must be considered simultaneously to select a compromise design.

At present, the conversion efficiency of high concentrated photovoltaic modules is about 30%, most of the solar energy is converted into heat, which will result in solar cell temperature rise and subsequent module efficiency decrease. For existing module with large solar cell, the heat source is concentrated and additional cooling fins must be used, resulting in high system complexity and cost rise. In order to lower the cost of photovoltaic, we developed distributed cooling type module with simple structure. This paper depicts a distributed cooling design for high concentrated photovoltaic module, as well as the thermal simulation of this design with analysis software. Module prototype was also made to test the actual effect. The final outdoor results showed high consistency with the simulation results. The chip temperature can be lower than 45℃ and the module outdoor working efficiency is higher than 26% ，and lower temperature provide a guarantee of long-term reliability to module packaging material.

It is well known that conventional GaInP/GaInAs/Ge three-junction (3J) solar cells are difficult to continue to ascend when the efficiencies reach 32% and 42% under AM0 and AM1.5D concentrated, respectively. In AlGaInP/AlGaInAs/GaInAs/GaInNAs/Ge five-junction (5J) solar cells, the performance of the AlGaInP, AlGaInAs and GaInNAs sub cell is the key factor for conversion efficiency of the 5J solar cell. We investigate the AlGaInP/AlGaInAs/Ge 3J solar cell. By incorporating surfactant trimthylantimony into the AlGaInP material, the crystal quality of AlGaInP is improved and the spectrum absorption range of AlGaInAs is extended. The current density of each sub cell exceeds 11.3 mA/ as is desired. Then we apply this 3J structure to grow the lattice-matched 5J solar cell and obtain the short circuit current of 134.96 mA, open circuit voltage of 4399.6 mV, fill factor of 81.7% and conversion efficiency of 29.87%.

AlGaInP is a prospectively valuable material for high-efficiency lattice-matched tandem AlGaInP/AlGaInAs/GaAs/GaInNAs/Ge (2.05/1.7/1.4/1.0/0.7 eV) five-junction solar cells. We examine the optical properties of AlGaInP materials with trimethylantimony (TMSb) incorporated at various flow speeds. Then, we apply Al0.1GaInP with TMSb incorporated at 15.6 µmol/min, whose band gap is 2.04 eV, to the fabrication of an AlGaInP/Ge double-junction (DJ) solar cell. Moreover, we analyze the photovoltaic current density–voltage (J–V) characteristics, external quantum efficiencies (EQEs), and internal quantum efficiencies (IQEs) of DJ cells under a 1-sun AM0 spectrum. As elsewhere, Sb incorporation improves the crystal quality of AlGaInP and the fill factor of the DJ solar cell; on the other hand, it increases the band gap of AlGaInP. Al0.08GaInP with Sb incorporation shows the same absorption edge of EQE as Al0.1GaInP without Sb incorporation, and J sc increases approximately by 15.3% owing to the reduction of 2% Al composition.

The dynamic on-line monitoring system (DMS) based on on-line training of artificial neural network (ANN) has been successfully implemented in a refinery for real-time, on-line and dynamic estimation of quality indexes of fractionator side draw. To improve the predicted accuracy of DMS and fit the new production cases, a novel ANN training method, on-line training method, has been proposed. It can save a lot of time and effort in contrast to the conventional off-line training for ANN. It also improves the reliability of DMS.

Because industrial process is often under changes, it is necessary to reconcile the measurement of the dynamic process. There are many problems in the present dynamics data reconciliation methods, such as low calculation efficiency, difficulty of treatment for the reconciliation of input variables. Based on the analysis of the characteristic of dynamic data reconciliation, an integral approach is presented which integrates finite element collocation method, filtering technique and robust method. The finite element collocation method can reduce the amount of discrete model constrained equations to decrease the problem complexity without any loss of measurement information. The filtering technique can eliminate random errors in input variables effectively and no lag or signal distortion will be introduced. Monte Carlo method is used to test the efficiency of the robust method for gross error detection. The calculation results show that the integral approach can improve the calculation efficiency greatly and can deal with the gross error of abnormal type properly.

We directly grow a lattice matched GaInP/GaInAs/GaInNAs/Ge (1.88eV/1.42eV/1.05eV/0.67eV) four-junction (4J) solar cell on a Ge substrate by the metal organic chemical vapor deposition technology. To solve the current limit of the GaInNAs sub cell, we design three kinds of anti-reflection coatings and adjust the base region thickness of the GaInNAs sub cell. Developed by a series of experiments, the external quantum efficiency of the GaInNAs sub cell exceeds 80%, and its current density reaches 11.24 mA/cm2. Therefore the current limit of the 4J solar cell is significantly improved. Moreover, we discuss the difference of test results between 4J and GaInP/GaInAs/Ge solar cells under the 1 sun AM0 spectrum.

At present, the applications of Al x Ga 1−x N are extensive, such as for visible-blind ultraviolet detectors, laser diodes, light emitting diodes (LEDs) and HEMTs. In this paper, Al 0.25 Ga 0.75 N and Al 0.32 Ga 0.68 N films have been grown on 2 in Si (iii) substrates by MOCVD. The low-temperature (6 K) photoluminescence (PL) spectrum and XRD rocking curve measurements have been employed to study the crystal quality of samples, and the phonon replica peak can be observed, which indicate that the samples have better quality in a small-localized region. The surface morphology of samples was investigated by AFM and the result of wavy surface agrees with the deduction from XRD rocking curve measurements. The sheet resistance mappings have been shown, and it indicates the nonuniformity of AlGaN film on Si (iii) will increase sharply as the Al content increases.

GaInNAs materials with narrow bandgaps of 1.10 eV have been grown on a Ge substrate by metalorganic chemical vapor deposition to fabricate GaInNAs/Ge (1.10/0.67 eV) double-junction solar cells. We have studied the photovoltaic characteristics and the external quantum efficiencies of the double-junction cells with various annealing conditions and different GaInNAs base layer thicknesses. The best external quantum efficiency is obtained from the double-junction cell with a 1170 nm thick GaInNAs base layer annealed at 675 °C for 30 min. Under AM1.5G illumination, the best double-junction cell has a short circuit current density (J SC) as 23.63 mA cm−2, which is dominated by the J SC of the GaInNAs subcell.

In the scheduling models for batch processes, changeovers are considered to be sequence-dependent, which is the most general situation, or only unit-depended. In recent literature, most continuous-time methods only consider unit-dependend changeovers, which cannot represent the real-world situation In this paper, a new MILP model for scheduling of batch process with sequence-dependent changeovers has been presented. It is based on a new continuous-time representation method that dose not rely on the definition of time slots. Accessorial binary variables are introduced to indicate whether there is any task processed at each unit so that the sequence constraints are presented in a more compact way. Computational case study has shown the efficiency of the new model.

The periodic operation of semi-continuous dynamic processes (SCDP) could be approximated by dozens of pseudo steady-state models, such that optimization of SCDP is used to determine the operating variables of each steady-state model. A new optimization strategy with consideration of uncertainties for ethylene pyrolysis process, which was a typical SCDP, was proposed in this paper. The optimization strategy made the operations during each steady-state time interval have some specified flexibility, which made the optimization results applicable in practice. According to the optimization model structure of SCDP, parallel computation technique was used to accomplish the optimization strategy.

This paper considers the synthesis of systems of heat integrated distillation columns. The goal is to choose the configuration which has the maximum structural flexibility, a concept introduced in Part I of this series. In this work we consider only the simpler structures where columns are “stacked” one upon the other and where none of the tasks is multieffected. Two representations allow us to enumerate all the possible dominant constraint sets for such processes. Searching over dominant constraint sets is a much smaller search than searching over all alternative stackings. Under certain useful assumptions, these insights yield a particularly fast search algorithm for finding the better stackings by hand. The paper also shows how to write a more complete mixed integer linear programming model for this problem. This model includes column temperatures explicitly and thus allows constraints that limit the temperature ranges within which each of the columns must operate. It also permits the heat duty for each column to be a linear function of temperature. Examples illustrate each of the ideas.