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• Integrated demand response mechanism (IDR) in the micro-energy grid can reduce the peak-valley difference of load, promote supply–demand balance and improve the economy of system operation. • Power to gas (P2G) and combined heat and power (CHP) devices can effectively improve the coupling relationship of electricity, gas, and heat in the micro-energy grid. • Through various devices in this paper, the inflexible operation strategy of the traditional micro-energy grid is decoupled, and the determining electricity by heat characteristic limitation of CHP units is relieved. • The simulation results show that the ladder-type carbon trading mechanism has a more potent binding force on carbon emissions and can effectively improve the environmental protection of the system. • In the process of solving, the sequence operation theory (SOT) methods can be used to solve the model quickly and accurately. The micro-energy grid can meet various load demands and realize the complementary advantages of different energy sources, which provides a new way to solve the problems of energy utilization efficiency and environmental pollution. However, how coordinating multiple energy sources and improving the flexibility of the micro-energy grid is an urgent problem to be solved. This paper proposes an optimal scheduling model based on chance-constrained programming (CCP), which considers electric vehicle (EV) charging characteristics, integrated electricity-heat demand response, and ladder-type carbon trading in the background of various renewable uncertainty. Firstly, this paper uses power to gas (P2G) technology and combined heat and power (CHP) technology to improve the flexibility of the system and realize the coupling between different energy sources. Secondly, integrated demand response (IDR) is used to explore potential interaction capabilities between electric-heat flexible load and micro-energy grid. Then, the ladder-type carbon trading mechanism is introduced in the optimization scheduling model to reduce the carbon emissions of the system. Finally, sequence operation theory (SOT) transforms the original CCP model into a conveniently solvable mixed-integer linear programming (MILP) model. The simulation results show that all subsystems are closely coupled due to the participation of P2G and CHP, which reduces the operation cost of the system by 3.9 %. The results also indicate that the IDR mechanism improves energy efficiency and reduces operating costs by 7.8 %. Finally, the results substantiate that the ladder-type carbon trading mechanism reduces the carbon emissions of the system by 18.1 % and improves the environmental benefits of the system. [ABSTRACT FROM AUTHOR]

Abstract: Dynamic simulation on the broken conductors for an experimental line section under different load cases was carried out. A finite element model of three span conductors was established in the general software ANSYS. The broken load case can be realized by the birth-death element method in ANSYS. The damping coefficients by the experimental identification were applied to the FEA model. Effect of the damping property of the conductors was considered by the Rayleigh damping method. Dynamic responses of the tensions of the conductors were obtained. Both the residual static tensions and the first peak tensions by the numerical simulations were well agreed with the experimental values. The impact effect is more significant for the location nearer to the broken point. The dynamic impact factors decrease with the increasing of the ice thickness, and the impact factors of conductors without accreted ice are much higher than those of conductors with accreted ice. [Copyright &y& Elsevier]

Abstract: Detemplation of zeolite MCM-56 was successfully realized by controlled oxidation of the template using H2O2 at 363 K. The resulting material (denoted as MCM-56(H2O2)) shows larger surface area (micropore and external), higher micropore volume, more Lewis acid and Brønsted acid sites in comparison with the sample detemplated by calcination (denoted as MCM-56(C)). Moreover, two Mo-containing catalysts of Mo/H-MCM-56(H2O2) and Mo/H-MCM-56(C) were prepared, and their catalytic properties for the reaction of methane aromatization were investigated. Compared with Mo/H-MCM-56(C), the sample of Mo/H-MCM-56(H2O2) shows higher conversion of methane and yield of benzene, with lower selectivity to benzene and higher selectivity to coke. The relatively high benzene yield might be mainly assigned to the existence of more 10-ring channels, while the high selectivity of coke should be due to the presence of large amounts of 12-ring pockets and acid sites exposed to the crystal exterior over Mo/H-MCM-56(H2O2). [Copyright &y& Elsevier]

Abstract: In this paper, the primary resonance of Duffing oscillator with two kinds of fractional-order derivatives is investigated analytically. Based on the averaging method, the approximately analytical solution and the amplitude–frequency equation are obtained. The effects of the two kinds of fractional-order derivatives on the system dynamics are analyzed, and it is found that these two kinds of fractional-order derivatives could affect not only the linear viscous damping, but also the linear stiffness, which could be characterized by the equivalent damping coefficient and the equivalent stiffness coefficient. The different effects are analyzed based on these two deduced equivalent parameters, when the two fractional orders are limited in the typical intervals, i.e. p 1∈[0 1] and p 2∈[1 2]. Moreover, the comparisons of the amplitude–frequency curves obtained by the approximately analytical solution and the numerical integration are fulfilled, and the results certify the correctness and satisfactory precision of the approximately analytical solution. Especially, the effects of the parameters in the second kind of fractional-order derivative are studied when the coefficient of the first kind of fractional-order derivative is zero or not. At last, two special cases for the coefficient of the second kind of fractional-order derivative are analyzed, which could make engineers obtain satisfactory vibration control performance and keep the frequency characteristic almost unchanged. These results are very useful in vibration control engineering. [Copyright &y& Elsevier]

Energy hub has positive significance in absorbing renewable energy, improving energy utilization efficiency and reducing carbon emissions. Considering both linearization energy hub model and nodal integrated energy-carbon price, a low-carbon economic operation model of energy hub is constructed by taking advantage of the bi-level optimization structure. First, in order to simplify the modeling procedures and improve the solving efficiency, reversibility judgment criteria and linearization processes in energy hub modeling are improved. Then, a nodal integrated energy-carbon pricing strategy is proposed and calculated according to flow tracing method and carbon emission flow method. Additionally, the bi-level optimization model and solution procedure are presented to obtain the optimal operating states of energy hubs. At last, for the simulation results, the characteristics and the influence of nodal price on energy consumption behaviors of energy hubs are analyzed, the proposed model is effective to reduce the carbon emissions and operating costs. • A simplified linearization model method of energy hub is proposed. • An integrated energy-carbon price is presented to minimize the total operation cost. • A bi-level optimization framework is established to study the operation of energy hub. • The simulation results illustrate the effectiveness in carbon emission reduction. [ABSTRACT FROM AUTHOR]

Energy efficiency and carbon mitigation are important issues in modern energy systems research. Considering the couplings between energy and carbon, this paper investigates a carbon-embedded energy coordination problem in a park-level integrated energy system (PIES). Firstly, based on energy hub, a multilateral interactive transaction framework is introduced, consisting of energy hub operator (EHO), building users with photovoltaics, and an electric vehicle (EV) charging agent. Secondly, a time-varying carbon emission measurement model for the outsourced electricity is designed, taking into account the dynamic composition of the supply-side generators. Based on the time-varying carbon factor and virtual carbon emission flow, an energy-carbon pricing strategy is proposed to balance the carbon responsibility among different participants. Then, a multi-agent interactive trading model in the PIES is constructed, where the energy consumption plans of building users and EVs are guided by the dynamic energy-carbon integrated prices. Through the iterative interaction among different agents, the optimal trading results are finally obtained. Simulation results illustrate the effectiveness of the proposed energy-carbon integrated pricing method in reducing carbon emissions and promoting energy sharing. • A carbon-embedded multilateral energy interaction mechanism in a PIES is discussed. • A time-varying carbon emission measurement model is established. • An energy-carbon integrated pricing strategy based on the dynamic carbon factor and virtual carbon emission flow is designed. • The impacts of energy-carbon integrated pricing on the scheduling of the PIES and carbon emission are investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] The effect of the accreted ice was considered. [•] The damping coefficients of the conductors were measured. [•] The main conclusions in this manuscript are based on a full scale broken test. [•] The contact effect between the conductors and the ground is considered. [ABSTRACT FROM AUTHOR]