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Flower-like particles (FLPs) with hierarchical surface architectures have recently attracted considerable attention due to their potentially wide application range. Hitherto, nearly all FLPs were fabricated using inorganic compounds, while versatile organic polymers have not received sufficient attention yet. Herein, we show the construction of novel organic, polymeric FLPs with diameters of 2.5-5 μm using cellulose stearoyl esters (CSEs) by means of the crystallization of side chains. CSEs with degrees of substitution of approximately 3 were transformed into FLPs during the gradual precipitation of polymer chains from the mixture of their solutions in dichloromethane (DCM) and a nonsolvent, which is driven by the evaporation of DCM. Ordered petal-like nanostructures were formed on the particle surface through the crystallization of side chains. Finally, partially crystalline FLPs containing lamellar structures were obtained. Moreover, the formation process was strongly affected by the molecular weight of CSE, concentrations of CSE solutions and the volume ratio between DCM and nonsolvents.

Grand-canonical Monte Carlo simulations were carried out to investigate the adsorption and separation of the binary mixture of CO2, SO2, and H2S in neutral and charged armchair single-walled carbon...

Carbon nanotubes (CNTs), as a gas adsorbent with electrical conductivity, are one of the most promising functional materials for electric swing adsorption. By using a grand-canonical Monte Carlo me...

In view of the fact that the monitoring data in large-scale distribution network has the characteristics of quantifiable, real-time, dynamic and so on, and the data storage capacity is insufficient, this paper puts forward the design of the real-time monitoring data expansion intelligent upgrading system in the distribution station area. Realizes the monitoring data expansion capacity intelligence enhancement. Through designing the hardware module of expanding capacity and installing the data acquisition interface, the hardware design of intelligent upgrading of monitoring data expansion capacity is realized. On this basis, the hierarchical extended storage mechanism is used to store the data node information. The real-time reading and querying function of the data is realized, and the capacity ratio of the monitoring data is calculated. Finally, the intelligent upgrading system of the real-time monitoring data expansion capacity is realized.

Because the current power supply does not take into account the regional climate cold and hot issues, leading to some areas of power energy supply is greater than demand, waste a lot of unnecessary electricity, power utilization rate is low. To solve the above problems, a multi-area integrated energy dispatching method based on large data analysis is proposed. Firstly, the data warehouse method is used to integrate the supply and demand data of multi-region related comprehensive energy sources, then the integrated data is processed, and then the power demand level is divided based on fuzzy clustering. Finally, the multi-region power is reasonably supplied according to the level, and the comprehensive energy dispatch of cooling, heating and power is completed. The experimental results show that the multi region integrated energy scheduling method based on big data analysis can reduce the average power supply power by 353.534 kW, and improve the utilization rate of electric energy.

In the traditional distributed hybrid energy storage structure, there are security, island operation and capacity blocking. For this reason, a distributed hybrid energy storage structure voltage reactive power control algorithm is proposed based on big data analysis. First, establish a voltage reactive power control model, using the control or manual operation of the communication system to achieve automatic operation of the transformer tap or capacitor input capacity. Secondly, the Nash theorem is used to calculate the physical quantity obtained by the secondary user under certain transmission power conditions. Based on the game theory, the operating data of the power grid is obtained, and then the voltage reactive power control algorithm is realized. Finally, experiments show that the distributed reactive energy storage structure voltage reactive power control algorithm based on big data analysis has certain advantages compared with the traditional voltage reactive power control algorithm.

Traditional data mining algorithms have problems such as poor applicability, high false positive rate or high false positive rate, resulting in low security and stability of the power system. For this reason, the regional photovoltaic power generation data mining algorithm is studied. Classification of data sources facilitates correlation calculations, and matrix relationships are used to calculate data associations. Combined with the data relevance, the association rules are output, and the output results inherit the clustering processing and time series distribution of the implicit data, thereby realizing the extraction of hidden data and completing the regional photovoltaic power generation data mining. The experimental results show that the regional PV power generation data mining algorithm has high stability and can effectively solve the system security problem.

The traditional algorithm is a combination of fuzzy dynamic programming and priority-based heuristic rules. The optimization performance of interruptible load scheduling is poor. For this reason, the central air conditioning load interruptible scheduling algorithm is proposed based on big data analysis. The algorithm adopts the characteristics of central air conditioning load management and selects the time scale of central air conditioning load scheduling. By optimizing the flexibility of interruptible scheduling, based on the central air conditioning load interruptible scheduling model, the optimal individual in the last generation population is decoded by binary coding, so as to realize the central air conditioning load interruptible scheduling algorithm. The experiment proves that the central air conditioning load interruptible scheduling algorithm has strong optimization performance.

In order to solve the problem of low precision in the analysis of power interruptible load demand using traditional power interruptible load demand response model, a power interruptible load demand response model based on big data analysis is studied in this paper. Firstly, the demand response is implemented by enabling technology, then the dynamic peak-valley price is determined by the demand response. Finally, the power interruptible load demand response model based on big data analysis is realized by using dynamic peak-valley price. The effectiveness of the demand response model based on big data analysis is verified by experiments.

Fast mass transport was identified for gas through nanoscale pores, especially those fabricated from carbon nanotubes and graphene sheets. Even in porous media such as sedimentary rock, it is commonly believed that there exists the well-known Klinkenberg effect due to gas slip. Here, we use molecular simulation to show that the flow enhancement of methane breaks down in calcite nanopores of shale reservoirs. The Klinkenberg effect fails to characterize methane transport through interparticle pores of calcites, and the molecules travel even slower than the prediction of Hagen–Poiseuille equation. The comparison of methane transport in graphene, quartz, and calcite nanopores suggests that this behavior arises from the strong attractive potential and the lack of atomically ultrasmooth surface in calcite, thus leading to the presence of particles sticking at the interface. The Navier–Stokes equation, coupled with a negative slip length and bulk viscosity, can provide a reasonable description of methane flow t...

Carbon nanotubes (CNTs) have been identified as extremely promising candidates for gas capture and storage. Therefore, an understanding of the adsorption mechanisms is crucial to the improvement of CNT applications. In this work, grand-canonical Monte Carlo simulations and analytical models are used to study, at the temperature of T = 303 K, the adsorption and condensation of SO2 in hexagonal arrays of double-walled CNTs of different inner nanotube radii Rin and intertube distances d. For both the inner and the outer adsorption, type I and type IV adsorption isotherms (IUPAC classification) are observed; they can be described adequately by analytical models. At a given pressure, the maximum adsorption among different CNT geometries depends strongly on the applied pressure. For the inner adsorption, three stages of adsorption are identified with increasing pressures. At low pressures, only one monolayer is formed, where the adsorption energy dominates the adsorption. At intermediate and high pressures, mul...

Two constitutive models, the modified Johnson-Cook model and the logarithm linear relation model based on empirical approach and data analysis, were presented to illustrate compressive deformation of magnesium alloys AZ80 under multiple loading directions and strain rates. The results of stress-strain curve analysis and sensitivity index analysis suggested that the stress held large fluctuations in loading direction of 90°. Model testing signified that the logarithm linear relation model was more proper than the modified Johnson-Cook model in view of relative mean square error and correlation coefficients. Moreover, numerical simulation building on established models also indicated that the logarithm linear model is more precise than the modified Johnson-Cook model.

This work introduces a nonequilibrium molecular dynamics method for calculating the mutual diffusion coefficient for mixtures. The method is based on the idea of the reverse nonequilibrium molecular dynamics algorithms, and artificially generates a mass flux through the Lennard–Jones mixtures by suitably exchanging particle positions and velocities in different regions. The analysis of the resulting steady-state concentration profiles allows the calculation of the mutual diffusion coefficient. As a test, this method is applied to the calculation of the mutual diffusion coefficient of Ar/Kr systems, and reasonable results are obtained. At the same time, it is observed that the mutual diffusion coefficient strongly depends on the temperature and composition of the mixture. The method can be easily extended to other fluid mixtures and be adopted when studying the nonequilibrium fluid mixtures.

The hot deformation behaviors of Aluminum alloy C919 were studied in the present investigation. The hot compression tests for C919 were carried out in the temperature range of 350°C~470°C and strain rates range of 0.001s-1~1s-1 using GLEEBLE-1500 thermal simulate testing machine. Optical microscopy (OM) was used for the microstructure characterization. The experimental results showed that the flow stress of C919 aluminum alloy decreased with increasing temperature and decreasing strain rates and the flow stress curves tended to increase at a strain rate of 1s-1 with increasing strain, while the flow stresses kept with increasing strain at lower strain rate. The alloys were more prone to dynamic recrystallization with decreasing strain rates during hot deformation. The hot compression behavior of C919 aluminum alloy can be described as hyperbolic sine function corrected Arrhenius relation. The processing maps for the alloy were built at a strain of 0.6. The instability deformation domain occurred at temperatures range from 350°C and 380°C and at a strain rate of 0.1-1s-1. Based on the processing maps and microstructure observations, the optimum hot-working parameters were determined to be at a temperature of 470°C in the strain rate range from 0.1-0.01s−1 for the C919 aluminum alloy.

Using both theory and experiment, we investigate the possibility of creating perfectly ordered block copolymer nanostructures on sparsely patterned substrates. Our study focuses on scrutinizing the appropriate pattern conditions to avoid undesired morphologies or defects when depositing cylinder-forming AB diblock copolymer thin films on the substrates which are mostly neutral with periodic stripe regions preferring the minority domain. By systematically exploring the parameter space using self-consistent field theory (SCFT), the optimal conditions for target phases are determined, and the effects of the chemical pattern period and the block copolymer film thickness on the target phase stability are also studied. Furthermore, as a sample experimental system, almost perfectly aligned polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) diblock copolymers are demonstrated. After the pattern transfer process, highly ordered Al nanodot arrays following the initial vertically aligned cylinder pattern are created. This systematic study demonstrates the ability to control the structure and the position of nanopatterns on sparse chemical patterns.

For the bottleneck of electric vehicle short range and energy supply inconvenience to restrain the fast development of electric vehicle, from the perspective of the electric vehicle power charging model, through analyzing the current situation and developing trend of electric vehicle charging facilities, consulting the existing electric vehicle charging model of advice, and borrowing from the mature business operation model of other domestic industry, one kind of proposal of suitable for the domestic electric vehicle current situation of power supply mode is analyzed. The proposal can provide reference for domestic electric vehicle scale and rapid development.

The deformation behaviors of as-cast Mg-11Gd-2Y-Zn-Zr magnesium alloy were investigated by compression test with Gleeble-1500 thermal simulator at temperature of 623-753K and strain rate of 0.01-0.5 s-1. The flow stress behaviors of the magnesium alloy were carried out at a strain of 0.7. The strain rate and deformation temperature had great influence on the flow stress behaviors. The flow stress increases with increasing strain rate and decreasing temperature. The flow stress has more than one peak stress at a strain rate of 0.5s-1showing continuous dynamic recrystallization (DRX) mechanism, while other flow stresses exhibited only one peak stress indicating discontinuous dynamic recrystallization (DDRX) mechanism. It was also found that the flow stress behavior could be described by the hyperbolic sine constitutive equation, in which the determined average activation energy is 273.426 kJ·mol-1. The maximum error value between calculated value and experimental value is 5.5%. The deformation map was also established, and the best parameter for hot working was found to be 0.1s-1/753k approximately.

Smart Distribution Grid and Utilization are the important support for the development of Smart City and Smart Grid, meanwhile, the effective data communication and information exchange are the key points to implement them. First, analyze the unified communication method of Smart Distribution Grid and Utilization for each specific business. Then, respectively, from the current reality and future trends, propose two typical implementation:the interface adapter pattern and the integrated pattern, and establish specific implementation patterns, deployment patterns, and pattern evaluations, so as to provide the design of pattern level for the development of Smart Distribution Grid and Utilization.

The wind-solar-storage and other distributed generation (DG) accessing to the distribution grid and user’s interaction with the grid change the business’s forms of the traditional distribute and utilize system, and while the supplier and demander of electric power also set higher requirements on business’s functions of the smart distribution and utilization system. Based on business requirement of smart distribution and utilization, the major content and function of distribution and utilization link are discussed, including intelligent planning, intelligent dispatching, self-healing control, demand side management, two-way interaction and so on. It makes the architectures of business and the objectives of construction more clear and promotes the construction of the business system in the smart distribution and utilization system.

Accurate prediction of air-conditioning load is the prerequisite of commercial buildings actively participating in the operation of power grid. The strong correlation factors with air-conditioning load were analyzed in commercial building based on the empirical results, and a temperature sensitivity model of air-conditioning load was got. Considering the humidity, air-pressure and other seasonal difference, a correction sensitivity model with temperature and seasons is proposed. Finally the effectiveness of this model is validated by the calculation example of Shanghai Huitai Building.

The elevated temperature flow stress behavior of Mg-9Gd-2.5Y-1Nd-0.5Zr magnesium alloy was carried out by Gleeble-1500 thermal mechanical simulator in the temperature range of 460-520°C and in strain rates of 0.0005~1s-1 at a strain of 0.6. The optical microscopy was used for microstructure characterization. The results showed that the flow stress increases with increasing strain rates and decreasing temperature. All the deformed magnesium alloy specimens show a dynamic recovery characters in the temperature range from 460~500°C, and show dynamic recrystallization characters at 520°C. The flow stress of this alloy can be represented by Zener-Hollomon parameter function, and values of related parameters A, α and n, are 2.24×1013s-1、0.027MPa-1 and 2.93, respectively. Its activation energy for hot deformation Q is 212.6kJ/mol.

In comparison to single-stimuli responsive cellulose derivatives, multi-stimuli and reversibly responsive compounds from cellulose are still scarce. In this report, the fabrication of redox-controllable nanoparticles (NPs) from novel cellulose derivatives containing thiol groups and rhodamine spiroamide showing reversible fluorescence is described. The thiol groups were introduced into cellulose chains after esterification by 3,3′-dithiodipropionic acid and further reductive cleavage of disulfide bonds. Then, rhodamine spiroamide was immobilized via thiol–ene reaction between cellulose thiopropionyl ester and rhodamine B methacrylamide. The obtained cellulose derivative containing rhodamine spiroamide (cellulose-RhBMA) could be transformed into NPs in aqueous medium and dissolved again via redox reactions on thiol groups. At the same time, cellulose-RhBMA exhibited reversible fluorescence that could be switched using pH (protons) or UV-illumination/heating as external stimuli. In total, we demonstrated the fabrication of redox-controllable NPs with reversible fluorescence, and a novel platform for the chemical modification of cellulose via thiol–ene reaction.

Demand response has great significance to the optimal adjustment of the electricity load curve, and also reduces difference between grid peak and valley load. But the promotion and implementation of demand response in China faces many aspects of problems such as electricity price control, power grid electricity sales profit mechanism and so on. Based on interpreting the classic electricity demand response theory, we consider the actual situation of China's electric power system and take a balance consideration of the interests of the government, power generation, power grid companies and electricity users, to give a new interpretation of the concept of demand response, which enriches technology means and economic means of demand response. Besides the leading role and main roles of implementation, we introduce the role of the initiator, and put forward the implementation of demand response project design and automated implementation system. This paper belongs to the national science and technology support programwith the power grid low carbonization characteristics of the smart grid integration technology research and demonstration in Jiangxi Provinceand SGCC projectWith the power grid low carbonization characteristics of the smart grid integration technology research and demonstration.

Hot compression tests of 7075 extruded bar were carried out on the Gleeble-1500 thermal simulation machine at strain rates of 0.1 s-1 and 1s-1 and at temperatures of 320°C. The compression direction are aligned at 0°, 45°and 90°to the axis direction of the extruded bar. Microstructure and texture was characterized using Optical Microscopy and x ray diffraction analysis. The results show that the true stress of all specimen increases with decreasing temperature and increasing strain rates. Both the yield strength and the stable flow stress of the 0° specimens is the highest among all three specimens, while that of 45° specimen is the lowest. This could be attributed to the lamellar grain structures and the texture of the extruded bar. The microstructure of 0°specimen are of equiaxed grain due to dynamic recrystallization after compression, while the grain shape of 45°and 90°specimens are still of lamellar grain structure.

According to the requirements of distribution and consumption concept of smart grid, adaptive communication techniques are compared through the analysis of kinds of communication techniques. And detailed suggestions are given in this paper. Finally, several typical construction schemes of communication systems for distribution and consumption concept are presented according to the requirements of circumstance, operation and management of different cities.

The flow stress behavior and constitutive equation of the nanometric Al2O3particulate reinforced Al alloy matrix composites were investigated in the temperature range from 590k-710k, and at the strain rates range from 0.01s-1-1s-1. Hot compression tests were carried out with thermal simulation machine Gleeble-1500. The results showed that the values of the true stresses rose rapidly and then held constant to some extent after attaining the peak values with the increasing strains at different deformation condition. The flow stress for the composites increased with increasing strain rate, which means that the experimental material is a sensitive material of positive strain rate, and decreased with decreasing temperature. Dynamic recovery and dynamic recrystallization occurred during hot compression of the composites. The constitutive equation represented by a Zener-Hollomon parameter in an exponent-type and the deformation activation energy are as follows respectively: σ=71.43ln{(Z/4.37×1011)1/5.94+[(Z/4.37×1011)2/5.94+1]1/2}, Q=197KJ mol-1.

The influences of solution treatment, deformation strain, and nanometric Al2O3 particulate on dry wear properties for nanometric Al2O3 particulate reinforced Al alloy matrix Composites manufactured by casting were investigated. The result showed that both the wear resistance of AL matrix and the composites increased rapidly with increasing solution temperatures. The wear resistance increased slightly with increasing deformation strain for the composites. The wear resistance of the composites is higher than the AL matrix after the same deformation and heat treatment. Microstructure observation revealed that the grain sizes of the composites increased with increasing solution temperature and decreased with more severe deformation. Abrasive wear was the main wear mechanism both for the AL matrix and the composites.

The smart power consumption is an important orientation in peak load shifting and load shedding of power grid in particular time period. It has the significant effect to relieve the load shortage of the power grid. The large-scale electrical devices like central air-condition in commercial building have the great potential in the energy efficiency improvement and available load integration. The effectively regulation of power load in public and commercial construction can improve the stability and reliability of power grid. The power situation in china and the content of empirical study were introduced, and the system hardware design and software platform construction is demonstrated. The function modules of software platform and realization of regulation system are discussed in final.

This paper presents the results of an investigation of the effects of homogenizing heat treatment and extrusion on plasticity of the as-cast AZ80 magnesium alloy. Both the homogenized and non-homogenized billets of AZ80 alloy were forward extruded at several different temperatures and different extrusion ratios. The effects of homogenization and extrusion on plasticity were evaluated by conducting tensile tests on these billets at room temperature and comparing their elongations. The experimental results showed that the elongation of the as-cast AZ80 alloy was increased by 67% after the homogenization treatment. After extrusion, the elongation of both the homogenized and non-homogenized AZ80 alloy increased significantly. The elongation of the homogenized billets decreased gradually with increasing temperature. For the non-homogenized billets, however, the elongation decreased sharply with temperature from 300 to 350 °C and then increased gradually with increasing temperature. There was not clear correlation between the elongations of both the homogenized and non-homogenized billets and the extrusion ratio.

Based on the introduction of smart substation function architecture, the analysis method of use case was firstly recommended to study the main business information system of smart substation, involving protective relaying and automatic control. During analysis, demand of information interaction in lengthwise and crosswise direction and limits of the existing system was pointed out. Then in guide of system theory, control theory and information theory, integrated-control idea was proposed to improve the existing control system framework, the integration-control model and system architecture were analyzed. Finally, the project application of yan’an was given.

Uniaxial tensile tests of extruded 7075 aluminum alloy bar were carried out on the universal test machine at strain rate of 0.001 s-1. The tensile direction are aligned at 0°, 45°and 90°to the axis direction of the bar. Microstructure and texture was characterized using Optical Microscopy and x ray diffraction analysis. The results show that the yield stress for 0° orientation specimen, which was solution treated, is the highest, while that of 45° orientation is the lowest. The yield stresses are anisotropic for solution treated 7075 extruded bar, which could be attributed to the elongated grain structures and the texture of the bar. The yield stress anisotropic behavior diminished after peak aged.

Hot compression tests of 7075 aluminum alloy were carried out on the Gleeble-1500 thermal simulation machine at strain rates of 0.01 s-1 ,0.1s-1, 1s-1 and at temperatures of 320°C,400°C,480°C. The compression direction are aligned at 0°and 45°to the axis direction of the bar. Microstructure was studied using Optical Microscopy. The results show that the true stress of both specimen increases with the decrease of temperature and the increase of strain rates. The true stresses rose rapidly to peak value and then held constant or decreased with the increase of the true strains at different deformation conditions. The yield strength and stable flow stress of the specimens in 0° to the axis direction is higher than that of 45° specimen, which could be attributed to the elongated grain structures of the bar and the texture of the extruded bar.

The new energy power station in the islands is the central node with the ocean current energy,wind energy, solar energy,energy storage equipment and other types of new energy power generation confluencing,achieved intelligent monitoring and energy management for new energy power in the islands.Refer three layer and two network architecture of smart substation,presents the islands’s new energy power monitoring and energy management platform architecture,describes specific function and implementation method of the new energy power station with process layer,spacer layer and energy management layer.Based on the IEC 61850 ( Second Edition ) and IEC 61400-25 standard,the new energy power stations in the islands were standardized modelling,to ensure the platform standard and open.