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The pyrolysis separation of calcium and magnesium from phosphate tailings is an important process due to its high-value resource utilization. In this paper, aiming to address the problems of high energy consumption, a slow decomposition rate and the low activity of decomposition products in the high-temperature pyrolysis of phosphate tailings, the medium-temperature pyrolysis of phosphate tailings under a H2O atmosphere was carried out, and the phase reconstruction and activation of pyrolysis process were discussed. The results showed that compared with N2, air and CO2 atmospheres, the pyrolysis process of phosphate tailings in a H2O atmosphere was changed from two stages to one stage, the starting decomposition temperature was reduced to 500 °C and the decomposition time was shortened to 30 min. The order of the influence of each factor on the pyrolysis of phosphate tailings was temperature > H2O pressure > holding time. Under the optimized pyrolysis conditions, the yield of CaMg(CO3)2 decomposition of phosphate tailings into MgO and CaO was 97.3% and 98.1%, respectively, and the reactivity of MgO was 31.6%. The distribution of Ca and Mg elements in the phosphate tailings after pyrolysis showed a negative correlation, and both of them no longer formed associated compounds; Ca mainly existed in the form of Ca(OH)2, Ca5(PO4)3F, CaSiO3 and CaF2, and Mg mainly existed in the form of MgO, MgF2 and Mg(OH)2. [ABSTRACT FROM AUTHOR]

The pandemic situation of COVID-19 blocks many traditional information exchange paths, intensifies the information asymmetry in the implementation of the energy efficiency retrofitting project of existing building and seriously affects the decision-making effect of the energy performance contracting (EPC) subject. Therefore, based on the information-sharing platform, this paper constructs the synergistic incentive framework; designs the computational experimental models from the aspects of system information structure, system organization structure, synergistic communication strategy and subject knowledge structure; and analyzes the influence mechanism and evolution law of information on synergistic incentive performance from the two dimensions of the influence of the synergy cycle on the incentive performance and the influence of the incentive cycle on the synergy degree. The results show that increasing the information redundancy length and the information redundancy width can improve the synergy degree and incentive validity. The concentration of subject number or information dimension in a certain information area can quickly improve the synergy degree and incentive utility in the early stage of the synergistic incentive cycle, but the above situation is opposite in the later stage. Increasing the information communication path is beneficial to the effective information dissemination among subjects and can improve the efficiency of the decision-making of the subjects. Lastly, considering the background of COVID-19 epidemic situation, this paper puts forward the remedial methods and coping strategies make up for the lack of synergistic incentive information between EPC subjects. Research results can provide strong support for the design of synergistic incentive mechanism of EPC subjects. [ABSTRACT FROM AUTHOR]

In the energy performance contracting (EPC) mode, the energy services company (ESCO) involved in energy efficiency retrofitting of existing buildings often faces the parallel construction of multiple tender segments and multi-professional subcontractors. The one-to-many structure for ESCO and subcontractors causes difficulties to the project quality management and directly affects the effect of energy efficiency retrofitting of existing buildings. Therefore, this paper constructs a revenue-sharing incentive model by considering situation where subjects have fairness cognition. Through the social calculation experiment of the model, results show the following: (1) increasing the revenue-sharing coefficient will help to optimize the engineering quality of energy efficiency retrofitting and increase the energy-saving income; (2) in order to get better incentive effect, the engineering quality grade of energy efficiency retrofitting should match with the incentive strength; (3) because of the impact of fairness cognition, the incentive level difference is too large, and the incentive effect will gradually weaken in the subsequent incentive cycle; (4) subcontractor's effort level changes can prompt ESCO to adjust the corresponding incentive intensity. Finally, some suggestions are put forward to optimize the engineering quality management of energy efficiency retrofitting of existing building, which is of great significance to improve the effect of energy efficiency retrofitting of existing building under EPC mode. [ABSTRACT FROM AUTHOR]

Low-altitude cellular-enabled Unmanned Aerial Vehicles (UAVs) provide potential supplementary platforms to assist air-to-ground cooperative communication. This paper investigates a joint safety information interaction scheme for a UAV-enabled network, which involves the complex constraints of three-dimensional trajectory planning, average energy efficiency optimization, and physical-layer security. Specifically, by modeling the UAV and the Ground Station (GS) as the transmit sources, we define the secure Energy Efficiency (EE) as the ratio of the total secrecy rate to the energy consumption of the whole system. Then, to achieve secure and energy-efficient communication in eavesdropping scenarios, we formulated the optimization problem as maximizing both the uplink/downlink secure EE of the system, subject to the constraints of the UAV's mobility and the allowable transmit power. For this highly coupled non-convex problem, a composite solution of joint fractional programming, alternate optimization, the bisection method, and the interior-point method is proposed to obtain the achievable EE. Simulation and performance analysis gave the conclusions that the joint optimization of trajectory and power allocation is capable of maximizing the information secure EE. Additionally, the secure EE increases with the increase of the average transmit power, which finally tends to be stable. [ABSTRACT FROM AUTHOR]

In this paper, a full life cycle resource consumption model for automotive seats has been proposed based on the vehicle material-energy-pollution assessment model, and an assessment on energy consumption and abiotic depletion potential (ADP) impact is conducted to evaluate the power seat environmental performances of a representative passenger car from the standpoint of life cycle. The results show that the energy consumption of the selected automotive seats mainly occurs in the use phase. Among all types of energy consumption, the non-renewable energy consumption is much larger than the renewable energy consumption. According to the ADP impact assessment, the consumption of copper and crude oil makes the largest contribution to resource depletion, and the ADP index may increase significantly due to the additional electrical part of car seats. Therefore, the enhancement of environmental performances of car seats can be achieved through measures including design with lightweight metal, fuel-electric conversion efficiency improvement, reduction in energy consumption caused by seat motor running and a more sustainable material with low ADP coefficient. [ABSTRACT FROM AUTHOR]

As a prominent member of freshwater and coastal fish faunas, Coilia nasus migrates annually from the sea up the Yangtze River in China to spawn. It is traditionally believed that C. nasus generally do not feed during their spawning migration. However, we recently documented the occurrence of food intake phenomenon in C. nasus following voluntary fasting. The purpose of the current study is to explore the metabolic mechanisms on C. nasus in response to food intake during migration. A total of 23,159 differentially expressed mRNA molecules and 204 metabolites were identified in transcriptome and metabolome analyses. Our results provide insights into the activation of energy consumption and reinforcement of energy storage during migration, and also identify key genes involved in food intake regulation. Our findings will be useful for future research on population recruitment and energy utilization in wild C. nasus. • Metabolic changes in feeding C. nasus were quantified for the first time. • Energy consumption was activated by feeding. • Energy storage was reinforced by feeding. • Metabolic mechanisms lay a foundation for the study of migratory ecology in C. nasus. [ABSTRACT FROM AUTHOR]

• The network is divided into several clusters. • Both the inter-cluster and intra-cluster correlation is utilized. • The measurement matrix is formulated based on the gathered data. • The proposed scheme maintains reconstruction accuracy under unreliable wireless links. • Network life is prolonged effectively. Packet loss is one of the most critical factors affecting the accuracy of compressed sensing (CS)-based data gathering algorithms. In this paper, a data gathering algorithm is proposed to decrease energy consumption and resist packet loss. Each cluster head formulates a sparsest random measurement matrix (SRMM) via the received data to avoid the measurement of the lost node and decrease the number of measurements. To employ spatial correlation between clusters, the sink constructs a block diagonal matrix (BDM) as a measurement matrix via SRMMs and reconstructs the entire network data. Additionally, the optimal number of clusters is discussed under this framework to reach the minimum power consumption. The SR-BDM is evaluated on the emulated data and the real sensor data from GreenOrbs, respectively. The simulation results indicate the proposed algorithm reaches high precision, both with reliable links and with a 60% packet loss rate link, without causing increased energy consumption. [ABSTRACT FROM AUTHOR]

Highlights: [•] Two novel turbocharging approaches of steam turbocharging and steam-assisted turbocharging were proposed. [•] Steam turbocharging has higher energy saving potential than the other two turbocharging approaches. [•] Steam turbocharging can achieve the target intake pressure in the entire IC engine speed area. [•] Steam-assisted turbocharging can improve IC engine intake pressure at the low-speed operating conditions. [ABSTRACT FROM AUTHOR]

Abstract: In order to evaluate the energy utilization efficiency of gasoline engine and predict the recovery potential for waste heat energy, energy distribution and waste heat energy characteristics of a naturally aspirated gasoline engine have been studied by combining the methods of energy and exergy analysis. During the research processes, engine energy balance tests were conducted under mapping characteristics, and the parameters required for calculating the energy balance and exergy balance were measured. On this basis, waste heat recovery potential and gasoline engine total exergy efficiency were studied by using the method of exergy analysis. Research results show: at low-speed and low-load, waste heat energy mainly focuses on cooling water; at high-speed and high-load, exhaust gas energy is larger than cooling water energy not only in quantity, but also in exergy percentage and exergy efficiency; the highest exhaust gas exergy efficiency appears in high-speed and high-load area, while the highest cooling water exergy efficiency appears in low-speed and low-load area; theoretically, total fuel efficiency of this gasoline engine can be nearly improved by a time through waste heat recovery, and the maximum total fuel efficiency can reach 60%. [Copyright &y& Elsevier]