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In view of large time delay and uncertainty of the main steam temperature system in a power plant, combining with internal model controller, a control method based on adaptive PSD is proposed. The advanced control algorithms have the advantages of the simple algorithm and the small calculating amount. Compared with the conventional cascade PID control system, the simulation results show that the self-adaptive PSD control system has better control performance on adaptability, such as to decrease the overshoot, shorten the settling time, accelerate the response, etc.

The synthesis of biodiesel from Jatropha curcas by transesterification is kinetically controlled. It depends on the molar ratio, reaction time, and temperature, as well as the catalyst nature and quantity. The aim of this study was to explore the transesterification of low-cost, inedible J. curcas seed oil utilizing both homogenous (potassium hydroxide; KOH) and heterogenous (calcium oxide; CaO) catalysis. In this effort, two steps were used. First, free fatty acids in J. curcas oil were reduced from 12.4 to less than 1 wt.% with sulfuric acid-catalyzed pretreatment. Transesterification subsequently converted the oil to biodiesel. The yield of fatty acid methyl esters was optimized by varying the reaction time, catalyst load, and methanol-to-oil molar ratio. A maximum yield of 96% was obtained from CaO nanoparticles at a reaction time of 5.5 h with 4 wt.% of the catalyst and an 18:1 methanol-to-oil molar ratio. The optimum conditions for KOH were a molar ratio of methanol to oil of 9:1, 5 wt.% of the catalyst, and a reaction time of 3.5 h, and this returned a yield of 92%. The fuel properties of the optimized biodiesel were within the limits specified in ASTM D6751, the American biodiesel standard. In addition, the 5% blends in petroleum diesel were within the ranges prescribed in ASTM D975, the American diesel fuel standard.

According to the technical requirements in the national standard GB/T 3836.1-2021 "Explosive atmospheres - Part 1: General requirements for equipment", the temperature test system under the most unfavorable conditions for explosion-proof lamps is designed, and the maximum operating power detection and trigger technology for temperature test of explosion-proof induction lamps is proposed.

The electric vehicle is one of the important transportation working under all weather conditions. The temperature characteristics of the Lithium-ion batteries in the electric vehicle play an important role on the operation performance of the electric vehicle. The charging and discharging experiments of a 50 A.h Lithium-iron phosphate battery under temperature range of minus 40°C to 40 °C are carried out to investigate the influence of the environment temperatures on the voltages, efficiency, internal resistance, the consistency and the cycle life of the battery in the charging and discharging procedures. The experiments are beneficial to the battery selection and the modeling and designing of the thermal management.

Abstract The rapid economic development of China has been accompanied by the emission of a great number of pollutants, which in turn have caused severe environmental problems. To strengthen environmental management and to establish a pollution source information database covering all key pollution sources and activities, China carried out its first National Census of Pollution Sources (NCPS) in 2007. The survey contents include the basic environmental situation in 2007, the generation levels of the main pollutants at that time, and the amount of pollution actually discharged into the environment after end-of-pipe treatment at all kinds of pollution sources. Based on the first NCPS report for China released in 2011, and taking two typical industry pollutants, sulfur dioxide (SO 2 ), and chemical oxygen demand (COD) as examples, we first revised the historical data concerning environmental statistics based on the NCPS documents. Subsequently, we analyzed the overall industrial scale in the change of SO 2 and COD emissions using index decomposition analysis, and then studied the contributions and comparative significance of the “three pollution emission reduction measures” put forward by the Chinese government. The latter are: Engineering Emission Reduction (EER), Structure Emission Reduction (SrER) and Supervision Emission Reduction (SuER). From these analyses, we were able to identify the main driving forces for SO 2 and COD emission reduction in China's industrial system. The results indicate that, with continually increasing pollution pressure caused by rapid economic development, EER and SuER have made the greatest contributions to reducing SO 2 and COD emissions; but SrER has not had an obvious effect. In the future, EER and SuER will gradually have less and less potential and become more challenging, while SrER should be achievable through adjusting the economic structure.

Abstract Nowadays the global demand for energy is growing rapidly in China, which will be the world’s largest country of energy consumption, it is thus highly urgent to conduct the research and development of efficient renewable wave energy equipment, e.g. wave energy converter (WEC). So, this paper aims to numerically develop a new WEC suitable for wave conditions in Zhoushan sea area. The specific research contents include the following aspects: (1) theoretic design by using the floating pendulum to capture the wave energy; (2) Computational Fluid Dynamics (CFD) simulation which is based on 3-Dimensional unsteady Reynolds Average Navier-Storkes (RANS) equations to analyze the hydrodynamic performance of floating pendulor capturing wave energy. The initial design has been optimized to find the parameters of swing device floating in different output loads of energy capture, and to recognize the conditions of the device for subsequent energy conversion system design.

An electric and thermal model of the hybrid device consisting of a dye-sensitized solar cell (DSSC) and a thermoelectric generator (TEG) is studied for exploiting the solar full spectrum. Analytical expressions for the power outputs and efficiencies of the DSSC, TEG and hybrid device are derived. Temperature-dependent coefficients of the DSSC are introduced and their values being consistent with the experimental data are determined. The effects of the operating electric current, working temperature and temperature-dependent coefficient in the DSSC on the performance of the hybrid device are discussed in detail. The optimum performance characteristics of the hybrid derive at different temperature conditions and the DSSC at the reference temperature condition are compared. The parametric design criteria of the optimal coupling are given. These results obtained here may provide some guidance for the optimum design of practical hybrid devices.

This work was aimed to comprehensively evaluate the potential for sustainable development of China's shale gas industry. It will contribute to the sustainable development of China's energy and economic. Factors of resource, technology, economy and environment were selected to develop the DPSIR framework evaluation indicators in system for shale gas based on the previous research. Next, The PPFCI (projection pursuit fuzzy clustering model) technique was developed by combining the projection pursuit model with a fuzzy clustering iterative model. So that it can deal with the multi-source, high-dimensional, fuzzy data of the proposed evaluation indicators. And then, the RAGA (accelerated genetic algorithm based on real coding) algorithm was developed to run the PPFCI technique. The results show that core technical capability, investment in projects of prevention of geological disasters, and ecological environment damage indicators were the key factors affecting the sustainability of China's shale gas industry. The potential for sustainable development of China's shale gas industry was relatively low. And it was unbalanced in different provinces. The potential for sustainable development of the southwest region was better than the northwest region. Among them, the development of Sichuan was more stable than Chongqing, with a 99% probability of maintaining a stable and sustainable development state, while Chongqing province has a 15%-20% probability to fluctuate towards the poles.

Energy storage is becoming increasingly important, both to mitigate intermittency in renewable generation and to reduce peak demand. However, storage remains expensive and so must be managed optimally. This paper considers the optimal management of storage that is subject to inefficiency in charging/discharging and to self-discharge, with the objective of minimizing energy costs. Notably, it shows that the less efficient the storage is, the less capacity is required to achieve the maximum peak-shaving benefit.