The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology pro...The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology provided by deep learning-based video surveillance for unmanned inspection of electrical equipment,this paper uses the bottleneck attention module(BAM)attention mechanism to improve the Solov2 model and proposes a new electrical equipment segmentation mode.Firstly,the BAM attention mechanism is integrated into the feature extraction network to adaptively learn the correlation between feature channels,thereby improving the expression ability of the feature map;secondly,the weighted sum of CrossEntropy Loss and Dice loss is designed as the mask loss to improve the segmentation accuracy and robustness of the model;finally,the non-maximal suppression(NMS)algorithm to better handle the overlap problem in instance segmentation.Experimental results show that the proposed method achieves an average segmentation accuracy of mAP of 80.4% on three types of electrical equipment datasets,including transformers,insulators and voltage transformers,which improve the detection accuracy by more than 5.7% compared with the original Solov2 model.The segmentation model proposed can provide a focusing technical means for the intelligent management of power systems.展开更多
The green and low carbon transition and development of the electricity industry is the most crucial task in realizing the“dual-carbon target”,and it is urgent to explore the incentive and subsidy mechanism to promot...The green and low carbon transition and development of the electricity industry is the most crucial task in realizing the“dual-carbon target”,and it is urgent to explore the incentive and subsidy mechanism to promote green electricity consumption and the cost-sharing strategy of carbon reduction,to alleviate the pressure of carbon abatement cost of each subject of the electricity supply chain.Against this background,this paper takes into account the low-carbon subsidies provided by the government and the incentive subsidies for users,and studies the optimal decision-making of each subject in the electricity supply chain,so that each of them can obtain the optimal profit and achieve carbon emission reduction at the same time.Firstly,taking into account the direct power purchase mode of large users and the electricity-selling companies emerging after the reform of the power sales side,we have established a cooperative mechanism for sharing the cost of carbon emission reduction in the electricity supply chain and clarified the relationship between the supply and demand of electricity among the main parties.Subsequently,considering government low-carbon subsidies and user incentive subsidies,the optimal decisionmaking model is established under two scenarios of decentralized and centralized cooperative games in the supply chain,respectively,with the objective of maximizing profits and carbon reduction rates.Solving for the optimal proportion of carbon abatement costs shared by each participant in the electricity supply chain in achieving game equilibrium.Finally,we analyze the role of the government’s low-carbon subsidies,users’incentive subsidies,and other factors on the profit and carbon reduction effect of the electricity industry through the example analysis and further analyze the impact of carbon abatement cost-sharing measures to provide recommendations for the electricity industry to realize low-carbon abatement and make decisions.展开更多
Objective:To investigate the effect of Yiqi Huoxue decoction combined with neuromuscular electrical stimulation on improving intensive care unit(ICU)acquired debility in mechanically ventilated patients.Methods:50 pat...Objective:To investigate the effect of Yiqi Huoxue decoction combined with neuromuscular electrical stimulation on improving intensive care unit(ICU)acquired debility in mechanically ventilated patients.Methods:50 patients who were admitted to the ICU and received mechanical ventilation treatment in our hospital from June 2022 to June 2023 and were complicated with ICU-acquired neurasthenia were selected,and randomly grouped using the randomized envelope method into two groups:control group with 25 patients who received neuromuscular electrical stimulation alone;observation group with 25 patients who received the traditional Chinese medicine Yiqi Huoxue decoction.Comparison indexes:treatment efficiency,degree of emotional recovery(APACHEⅡscore),muscle strength status(MRC score),motor status(FAC rating),and self-care ability(BI index score).Results:The treatment efficiency of patients in the observation group patients was higher as compared to those in the control group(P<0.05).There was no significant difference in the comparison of the results of the scores(ratings)of each index between the two groups before treatment(P>0.05).After the treatment,the APACHEⅡscores of patients in the observation group were significantly lower as compared to those in the control group,while the MRC scores,FAC ratings,and BI index scores were higher in the observation group than those of the control group patients(P<0.05).Conclusion:The combined application of Yiqi Huoxue decoction and neuromuscular electrical stimulation in the treatment of patients with ICU-acquired neurasthenia complicated by mechanical ventilation significantly enhanced the clinical efficacy,the patient’s muscle strength,motor status,and ability of self-care.Hence,it has high application value and is worthy to be popularized.展开更多
Various industries today rely on the support of electromechanical equipment,expanding its scope of application and leading to an increase in electromechanical installation projects.However,due to the high level of exp...Various industries today rely on the support of electromechanical equipment,expanding its scope of application and leading to an increase in electromechanical installation projects.However,due to the high level of expertise required and the potential risks involved,it is crucial to emphasize safety management during construction.This paper delves into the significance of construction safety management for electromechanical installation projects,identifies common problems encountered during construction,and proposes solutions.This analysis aims to provide relevant personnel with essential guidance and references for managing electromechanical installation projects safely.展开更多
Cadmium was replaced by zinc in ammoniacal system using an electrically enhanced method under ultrasonic waves.Five main influencing factors were investigated by a single-factor experiment to determine the optimum par...Cadmium was replaced by zinc in ammoniacal system using an electrically enhanced method under ultrasonic waves.Five main influencing factors were investigated by a single-factor experiment to determine the optimum parameters.Cyclic voltammetry and linear sweep voltammetry were applied to investigating the reaction mechanism of electrically enhanced cementation of cadmium on a zinc plate.The optimum parameters were a temperature of 35℃,a cathode-to-anode area ratio of 1:2,an anode current density of 15 A/m2,an ultrasonic frequency of 40 kHz a reaction time of 6 h and an ultrasonic power of 100 W.The extraction rate was 99.21%,and the production of byproduct“floating sponge cadmium”was inhibited.The analysis of the cyclic voltammetry and linear sweep voltammetry diagrams showed that ultrasonic waves can promote and accelerate the replacement reaction,decrease the voltage requirement of the electrically enhanced replacement reaction,and change the reaction steps.In addition,increasing the temperature and ultrasonic power can promote and accelerate electrically enhanced replacement reactions and decrease the electric potential requirement.展开更多
The analysis of a supervision environment is the first step for a company to enter the new electricity market. Transmission and distribution assets are the main investment targets of a company. The overseas power mark...The analysis of a supervision environment is the first step for a company to enter the new electricity market. Transmission and distribution assets are the main investment targets of a company. The overseas power market belongs to the regulated industry;whether it is a stock M&A project or a green land bidding project, the regulatory environment determines the assets. The level of return and investment risk that guides the operation strategy of existing overseas assets, has a significant impact on the investment and operations of international companies. A comprehensive and rapid assessment of the regulatory environment can help the project teams of international companies understand the macroenvironment of the target electricity market within a short period, quickly identify investment risks, qualitatively analyze the return level of the underlying assets, shorten the decision time, capture investment opportunities, and enhance the team. Efficiency and quality of work are factors of great importance.展开更多
The resin-matrix pantograph contact strip (RMPCS),which has excellent abrasion resistance with electrical current and friction-reducing function,was developed in view of the traditional contact strips with high mainte...The resin-matrix pantograph contact strip (RMPCS),which has excellent abrasion resistance with electrical current and friction-reducing function,was developed in view of the traditional contact strips with high maintenance cost,high wear rate with electrical current and severe damage to the copper conducting wire.The characteristics of worn surfaces,cross-section and typical elemental distributions of RMPCS were studied by scanning electron microscopy (SEM) and energy dispersion spectrometry (EDS).The wear behavior and arc discharge of RMPCS against copper were investigated with self-made electrical wear tester.The results show that the electrical current plays a critical role in determining the wear behavior,and the wear rate of the RMPCS against copper with electrical current is 2.7-5.8 times higher than the value without electrical current.The wear rate of the contact strip increases with the increase of the sliding speed and electrical current density.The main wear mechanism of RMPCS against copper without electrical current is low stress grain abrasive and slightly adhesive wear,while arc erosion wear and oxidation wear are the dominate mechanism with electrical current,which is accompanied by adhesive wear during the process of wear.展开更多
The effect of electric field on the mechanical properties and microstructure of AI-Li alloy containing Ce was investigated, and mechanism was discussed. The experimental results show that the ductility of the alloy is...The effect of electric field on the mechanical properties and microstructure of AI-Li alloy containing Ce was investigated, and mechanism was discussed. The experimental results show that the ductility of the alloy is enhanced by the electric field. The fracture features are changed and the precipitates are dispersed under the effect of the electric field. The mechanism discussion reveals that the effects of the electric field on the alloy are due to the change of the electron density in the alloy.展开更多
With the large-scale development of Chinese electric power, the contradiction of China’s energy supply and demand that reverse distributed is very prominent, therefore, promoting electricity trading is one of the imp...With the large-scale development of Chinese electric power, the contradiction of China’s energy supply and demand that reverse distributed is very prominent, therefore, promoting electricity trading is one of the important measures to get optimized configuration of energy resources in nationwide. For the two kinds of trading method, the “power point to the grid” trading and the “grid to grid” trading, this paper designed pricing mechanism model, and took one area as an example, we analyzed the impact of the participants by using different pricing mechanism, and put forward reasonable policy proposals for China’s pricing mechanism of trans-regional and trans-provincial electricity trading.展开更多
The Clean Development Mechanism,a flexibility mechanism contained in the KyotoProtocol, offers China an important tool to attractinvestment in clean energy technology and processesinto its electricity sector. The Chin...The Clean Development Mechanism,a flexibility mechanism contained in the KyotoProtocol, offers China an important tool to attractinvestment in clean energy technology and processesinto its electricity sector. The Chinese electricitysector places centrally in the country’s economy andenvironment, being a significant contributor to theacid rain and air pollution problems that plague manyof China’s cities and regions, and therefore a focusof many related energy and environmental policies.China’s electricity sector has also been the subjectof a number of economic analyses that have showedthat it contains the highest potential for clean energyinvestment through the Clean DevelopmentMechanism of any economic sector in China. Thismechanism, through the active participation frominvestors in more industrialized countries, can helpalleviate the environmental problems attributable toelectricity generation in China through advancingsuch technology as wind electricity generation, cleancoal technology, high efficient natural gas electricitygeneration, or utilization of coal mine methane. Inthis context, the Clean Development Mechanismalso compliments a range of environmental and energypolicies which are strategizing to encourage thesustainable development of China’s economy.展开更多
We investigate the evolution of interfacial gravity-capillary waves propagating along the interface be-tween two dielectric fluids under the action of a horizontal electric field.There is a uniform backgroundflow in e...We investigate the evolution of interfacial gravity-capillary waves propagating along the interface be-tween two dielectric fluids under the action of a horizontal electric field.There is a uniform backgroundflow in each layer,and the relative motion tends to induce Kelvin-Helmholtz(KH)instability.The com-bined effects of gravity,surface tension and electrically induced forces are all taken into account.Underthe short-wave assumption,the expansion and truncation method of Dirichlet-Neumann(DN)operatorsis applied to derive a reduced dynamical model.When KH instability is suppressed linearly by a consider-ably large electric field,our numerical results reveal that in certain regions of parameter space,nonlinearsymmetric traveling wave solutions can be found near the minimum phase speed.Additionally,the de-tailed bifurcation structures are presented together with typical wave profiles.展开更多
The electrical conductivities of single-crystal K-feldspar along three different crystallographic directions are investigated by the Solartron-1260 Impedance/Gain-phase analyzer at 873 K–1223 K and 1.0 GPa–3.0 GPa i...The electrical conductivities of single-crystal K-feldspar along three different crystallographic directions are investigated by the Solartron-1260 Impedance/Gain-phase analyzer at 873 K–1223 K and 1.0 GPa–3.0 GPa in a frequency range of 10-1 Hz–106 Hz. The measured electrical conductivity along the ⊥ [001] axis direction decreases with increasing pressure, and the activation energy and activation volume of charge carriers are determined to be 1.04 ± 0.06 e V and 2.51 ± 0.19 cm~3/mole, respectively. The electrical conductivity of K-feldspar is highly anisotropic, and its value along the⊥ [001] axis is approximately three times higher than that along the ⊥ [100] axis. At 2.0 GPa, the diffusion coefficient of ionic potassium is obtained from the electrical conductivity data using the Nernst–Einstein equation. The measured electrical conductivity and calculated diffusion coefficient of potassium suggest that the main conduction mechanism is of ionic conduction, therefore the dominant charge carrier is transferred between normal lattice potassium positions and adjacent interstitial sites along the thermally activated electric field.展开更多
The conductivity of non-crystalline fast ionic conductor for B_2O_3-Li_2O-LiCl-Al_2O_3 system is studiedin this paper. The glass structure of this system is discussed by means of infrared spectrum and X-ray fluorescen...The conductivity of non-crystalline fast ionic conductor for B_2O_3-Li_2O-LiCl-Al_2O_3 system is studiedin this paper. The glass structure of this system is discussed by means of infrared spectrum and X-ray fluorescence analysis, and the effects of LiCl and A1_2O_3 on the conductivity of Li^+ in the system are studied as well. Adding Li_2O to the system gives rise to transfer from [BO_3] triangular units to [BO_4] tetrahedral. When Li_2O content exceeds 30mol%, the main group of the glass is the diborate group with more [BO_4] tetrahedra. The adding of LiCl has no obvious influence on the glass structure, and LiCl is under a state dissociated by network, but with the increase of LiCl, the increase of conductivity is obvious. By adding A1_2O_3, the glass can be formed when the room-temperature is cooling down,the conductivity decreases while the conductive activatory energy increases for the glass. The experiment shows that conductivity in the room-temperature is σ= 6.2×10^(-6)Ω^(-1)cm^(-1), when at 300℃, the σ=6.8×10^(-3)Ω^(-1)cm^(-1). The conductive activatory energy computed is 0.6~1.0eV.展开更多
In order to obtain the Al wires with good mechanical properties and high electrical conductivities, conductive wires of Al-0.16 Zr, Al-0.16 Sc, Al-0.12Sc-0.04Zr(mass fraction, %) and pure Al(99.996%) were produced...In order to obtain the Al wires with good mechanical properties and high electrical conductivities, conductive wires of Al-0.16 Zr, Al-0.16 Sc, Al-0.12Sc-0.04Zr(mass fraction, %) and pure Al(99.996%) were produced with the diameter of 9.5 mm by continuous rheo-extrusion technology, and the extruded materials were heat treated and analyzed. The results show that the separate additions of 0.16% Sc and 0.16% Zr to pure Al improve the ultimate tensile strength but reduce the electrical conductivity, and the similar trend is found in the Al-0.12Sc-0.04 Zr alloy. After the subsequent heat treatment, the wire with the optimum comprehensive properties is Al-0.12Sc-0.04 Zr alloy, of which the ultimate tensile strength and electrical conductivity reach 160 MPa and 64.03%(IACS), respectively.展开更多
Objetives The mechanism for changes in the electrophysiological properties of the atria during rapid pacing induced atrial fibrillation(AF) is not well understood.We aimed to investigate the contribution of intrinsic ...Objetives The mechanism for changes in the electrophysiological properties of the atria during rapid pacing induced atrial fibrillation(AF) is not well understood.We aimed to investigate the contribution of intrinsic cardiac autonomic nervous system(ICANS) in chronic atrial electrical remodeling and AF induced by rapid atrial pacing for 4 weeks. Methods Twelve adult mongrel dogs weighing 15 to 20 kg were assigned to two groups;group 1(experimental group,n= 7) and group 2(control group,n =5).All dogs were anesthetized with propofol and mechanically ventilated via endotracheal tubes.The chest was entered via bilateral mini-thoracotomy at the fourth intercostals space.Bipolar pacing electrode was sutured to the right atrial appendage.Four-electrode catheters(Biosense-Webster,Diamond Bar,CA) were secured to allow recording at the right and left atriaum.All tracings from the electrode catheters were amplified and digitally recorded using a computer-based Bard Laboratory System (CR Bard Inc,Billerica,MA).Electrograms were filtered at 50 to 500 Hz.Continuous rapid pacing(600 bpm, 2×threshold[TH]) was performed at the right atrial appendage. Ganglionated Plexi(GP) was localized by applying high frequency stimulation(HFS;20 Hz,0.1ms duration, 0.5 to 4.5 V)with a bipolar stimulation-ablation probe electrode (AtriCure,West Chester,OH).Group1 underwent ablation of bilateral GP and ligament of Marshall followed by 4-week pacing.Group 2 underwent sham operaton without ablation of GP and ligament of Marshall followed by 4-week pacing.The effective refractory period(ERP) and window of vulnerability(WOV) were measured at 2×TH before(baseline) and every week after GP ablation.WOV was defined as the difference between the longest and the shortest coupling interval of the premature stimulus that induced AF.GP consist of the anterior right ganglionated plexi(ARGP) located in the fat pad at the right superior pulmonary vein(RSPV)-atrial junction;the inferior right ganglionated plexi(IRGP) located at the inferior vena cava/right atrial junction;the superior left ganglionated plexi(SLGP) at the left superior pulmonary vein(LSPV) /left atrial junction and the inferior left ganglionated plexi(ILGP) at the left inferior pulmonary vein (LIPV)/left atrial junction.Results Immediately after ablation, the ERP in Group 1 became markedly longer and started to shorten gradually during the first 2 weeks,then stabilized at the 4th week.Compared to Group2,the ERP of Group1 was significantly longer in the first 3 weeks(P【 0.05),but no obvious difference at the 4th week in either the right or left atrium(P】0.05).In Group 1,AF could not be induced(WOV=0)in the first 3 weeks after ablation, and at the 4th week,AF was induced in 2 of 7 dogs.In Group2,WOV progressively widened during the 4-week period. AF could not be induced in 5 of 7 dogs in Group 1 and 1 of 5 dogs in Group 2 during the 4-week pacing period. Conclusions The intrinsic cardiac autonomic nervous system (ICANS) plays an important role in the early stage of atrial electrical remodeling induced by rapid atrial pacing.On the other hand,with time passing by,its effect on the formation of AF decreases gradually,which suggests that ICANS may account for a non-dominant factor in the late stage of the rapid pacing-induced chronic atrial fibrillation.展开更多
Electricity pricing is the core of the power institutional reform in China, which is related to not onlyinterests redistribution of all parties, but also health and security of the entire power industry. Only byaccele...Electricity pricing is the core of the power institutional reform in China, which is related to not onlyinterests redistribution of all parties, but also health and security of the entire power industry. Only byaccelerating the reform on pricing mechanism can sound development of the power industry be promoted.展开更多
The buckling behavior of a typical structure consisting of a micro constantan wire and a polymer membrane under coupled electrical-mechanical loading was studied. The phenomenon that the constantan wire delaminates fr...The buckling behavior of a typical structure consisting of a micro constantan wire and a polymer membrane under coupled electrical-mechanical loading was studied. The phenomenon that the constantan wire delaminates from the polymer membrane was observed after unloading. The interfacial toughness of the constantan wire and the polymer membrane was estimated. Moreover, several new instability modes of the constantan wire could be further triggered based on the buckle-driven delamination. After electrical loading and tensile loading, the constantan wire was likely to fracture based on buckling. After electrical loading and compressive loading, the constantan wire was easily folded at the top of the buckling region. On the occasion, the constantan wire buckled towards the inside of the polymer membrane under electrical-compressive loading. The mechanisms of these instability modes were analyzed.展开更多
Cu-6%Fe(mass fraction) microcomposites containing(0-0.30)% rare earth elements were prepared by cold drawing and intermediate heat treatments.Microstructure was observed, and mechanical properties and electrical c...Cu-6%Fe(mass fraction) microcomposites containing(0-0.30)% rare earth elements were prepared by cold drawing and intermediate heat treatments.Microstructure was observed, and mechanical properties and electrical conductivity were measured for alloys at various drawing strain levels.Adding rare earth elements could reduce the size of primary Fe and Cu dendrites of Cu-6%Fe.Ultimate tensile strength increased but electrical conductivity decreased with the increase of drawing strain.Rare earth additions in Cu-6%Fe slightly increased the strength at low strain and effectively improved the conductivity at high strain.Both strain hardening rate and conductivity loss of Cu-6%Fe containing rare earths were reduced at lower strain than Cu-6%Fe.展开更多
基金Jilin Science and Technology Development Plan Project(No.20200403075SF)Doctoral Research Start-Up Fund of Northeast Electric Power University(No.BSJXM-2018202).
文摘The current existing problem of deep learning framework for the detection and segmentation of electrical equipment is dominantly related to low precision.Because of the reliable,safe and easy-to-operate technology provided by deep learning-based video surveillance for unmanned inspection of electrical equipment,this paper uses the bottleneck attention module(BAM)attention mechanism to improve the Solov2 model and proposes a new electrical equipment segmentation mode.Firstly,the BAM attention mechanism is integrated into the feature extraction network to adaptively learn the correlation between feature channels,thereby improving the expression ability of the feature map;secondly,the weighted sum of CrossEntropy Loss and Dice loss is designed as the mask loss to improve the segmentation accuracy and robustness of the model;finally,the non-maximal suppression(NMS)algorithm to better handle the overlap problem in instance segmentation.Experimental results show that the proposed method achieves an average segmentation accuracy of mAP of 80.4% on three types of electrical equipment datasets,including transformers,insulators and voltage transformers,which improve the detection accuracy by more than 5.7% compared with the original Solov2 model.The segmentation model proposed can provide a focusing technical means for the intelligent management of power systems.
基金supported by the Project of Philosophy and Social Science Foundation of Shanghai,China(Grant No.2020BGL011).
文摘The green and low carbon transition and development of the electricity industry is the most crucial task in realizing the“dual-carbon target”,and it is urgent to explore the incentive and subsidy mechanism to promote green electricity consumption and the cost-sharing strategy of carbon reduction,to alleviate the pressure of carbon abatement cost of each subject of the electricity supply chain.Against this background,this paper takes into account the low-carbon subsidies provided by the government and the incentive subsidies for users,and studies the optimal decision-making of each subject in the electricity supply chain,so that each of them can obtain the optimal profit and achieve carbon emission reduction at the same time.Firstly,taking into account the direct power purchase mode of large users and the electricity-selling companies emerging after the reform of the power sales side,we have established a cooperative mechanism for sharing the cost of carbon emission reduction in the electricity supply chain and clarified the relationship between the supply and demand of electricity among the main parties.Subsequently,considering government low-carbon subsidies and user incentive subsidies,the optimal decisionmaking model is established under two scenarios of decentralized and centralized cooperative games in the supply chain,respectively,with the objective of maximizing profits and carbon reduction rates.Solving for the optimal proportion of carbon abatement costs shared by each participant in the electricity supply chain in achieving game equilibrium.Finally,we analyze the role of the government’s low-carbon subsidies,users’incentive subsidies,and other factors on the profit and carbon reduction effect of the electricity industry through the example analysis and further analyze the impact of carbon abatement cost-sharing measures to provide recommendations for the electricity industry to realize low-carbon abatement and make decisions.
文摘Objective:To investigate the effect of Yiqi Huoxue decoction combined with neuromuscular electrical stimulation on improving intensive care unit(ICU)acquired debility in mechanically ventilated patients.Methods:50 patients who were admitted to the ICU and received mechanical ventilation treatment in our hospital from June 2022 to June 2023 and were complicated with ICU-acquired neurasthenia were selected,and randomly grouped using the randomized envelope method into two groups:control group with 25 patients who received neuromuscular electrical stimulation alone;observation group with 25 patients who received the traditional Chinese medicine Yiqi Huoxue decoction.Comparison indexes:treatment efficiency,degree of emotional recovery(APACHEⅡscore),muscle strength status(MRC score),motor status(FAC rating),and self-care ability(BI index score).Results:The treatment efficiency of patients in the observation group patients was higher as compared to those in the control group(P<0.05).There was no significant difference in the comparison of the results of the scores(ratings)of each index between the two groups before treatment(P>0.05).After the treatment,the APACHEⅡscores of patients in the observation group were significantly lower as compared to those in the control group,while the MRC scores,FAC ratings,and BI index scores were higher in the observation group than those of the control group patients(P<0.05).Conclusion:The combined application of Yiqi Huoxue decoction and neuromuscular electrical stimulation in the treatment of patients with ICU-acquired neurasthenia complicated by mechanical ventilation significantly enhanced the clinical efficacy,the patient’s muscle strength,motor status,and ability of self-care.Hence,it has high application value and is worthy to be popularized.
文摘Various industries today rely on the support of electromechanical equipment,expanding its scope of application and leading to an increase in electromechanical installation projects.However,due to the high level of expertise required and the potential risks involved,it is crucial to emphasize safety management during construction.This paper delves into the significance of construction safety management for electromechanical installation projects,identifies common problems encountered during construction,and proposes solutions.This analysis aims to provide relevant personnel with essential guidance and references for managing electromechanical installation projects safely.
基金Project (51574294) supported by the National Natural Science Foundation of ChinaProject (2018zzts447) supported by the Fundamental Research Funds for the Central Universities of Central South University, China
文摘Cadmium was replaced by zinc in ammoniacal system using an electrically enhanced method under ultrasonic waves.Five main influencing factors were investigated by a single-factor experiment to determine the optimum parameters.Cyclic voltammetry and linear sweep voltammetry were applied to investigating the reaction mechanism of electrically enhanced cementation of cadmium on a zinc plate.The optimum parameters were a temperature of 35℃,a cathode-to-anode area ratio of 1:2,an anode current density of 15 A/m2,an ultrasonic frequency of 40 kHz a reaction time of 6 h and an ultrasonic power of 100 W.The extraction rate was 99.21%,and the production of byproduct“floating sponge cadmium”was inhibited.The analysis of the cyclic voltammetry and linear sweep voltammetry diagrams showed that ultrasonic waves can promote and accelerate the replacement reaction,decrease the voltage requirement of the electrically enhanced replacement reaction,and change the reaction steps.In addition,increasing the temperature and ultrasonic power can promote and accelerate electrically enhanced replacement reactions and decrease the electric potential requirement.
基金supported by National Key Research and Development Program of China (2018YFB0904000)。
文摘The analysis of a supervision environment is the first step for a company to enter the new electricity market. Transmission and distribution assets are the main investment targets of a company. The overseas power market belongs to the regulated industry;whether it is a stock M&A project or a green land bidding project, the regulatory environment determines the assets. The level of return and investment risk that guides the operation strategy of existing overseas assets, has a significant impact on the investment and operations of international companies. A comprehensive and rapid assessment of the regulatory environment can help the project teams of international companies understand the macroenvironment of the target electricity market within a short period, quickly identify investment risks, qualitatively analyze the return level of the underlying assets, shorten the decision time, capture investment opportunities, and enhance the team. Efficiency and quality of work are factors of great importance.
基金Project (06FJ3041) supported by the Key Laboratory Open Foundation of Hunan Province, China
文摘The resin-matrix pantograph contact strip (RMPCS),which has excellent abrasion resistance with electrical current and friction-reducing function,was developed in view of the traditional contact strips with high maintenance cost,high wear rate with electrical current and severe damage to the copper conducting wire.The characteristics of worn surfaces,cross-section and typical elemental distributions of RMPCS were studied by scanning electron microscopy (SEM) and energy dispersion spectrometry (EDS).The wear behavior and arc discharge of RMPCS against copper were investigated with self-made electrical wear tester.The results show that the electrical current plays a critical role in determining the wear behavior,and the wear rate of the RMPCS against copper with electrical current is 2.7-5.8 times higher than the value without electrical current.The wear rate of the contact strip increases with the increase of the sliding speed and electrical current density.The main wear mechanism of RMPCS against copper without electrical current is low stress grain abrasive and slightly adhesive wear,while arc erosion wear and oxidation wear are the dominate mechanism with electrical current,which is accompanied by adhesive wear during the process of wear.
文摘The effect of electric field on the mechanical properties and microstructure of AI-Li alloy containing Ce was investigated, and mechanism was discussed. The experimental results show that the ductility of the alloy is enhanced by the electric field. The fracture features are changed and the precipitates are dispersed under the effect of the electric field. The mechanism discussion reveals that the effects of the electric field on the alloy are due to the change of the electron density in the alloy.
文摘With the large-scale development of Chinese electric power, the contradiction of China’s energy supply and demand that reverse distributed is very prominent, therefore, promoting electricity trading is one of the important measures to get optimized configuration of energy resources in nationwide. For the two kinds of trading method, the “power point to the grid” trading and the “grid to grid” trading, this paper designed pricing mechanism model, and took one area as an example, we analyzed the impact of the participants by using different pricing mechanism, and put forward reasonable policy proposals for China’s pricing mechanism of trans-regional and trans-provincial electricity trading.
文摘The Clean Development Mechanism,a flexibility mechanism contained in the KyotoProtocol, offers China an important tool to attractinvestment in clean energy technology and processesinto its electricity sector. The Chinese electricitysector places centrally in the country’s economy andenvironment, being a significant contributor to theacid rain and air pollution problems that plague manyof China’s cities and regions, and therefore a focusof many related energy and environmental policies.China’s electricity sector has also been the subjectof a number of economic analyses that have showedthat it contains the highest potential for clean energyinvestment through the Clean DevelopmentMechanism of any economic sector in China. Thismechanism, through the active participation frominvestors in more industrialized countries, can helpalleviate the environmental problems attributable toelectricity generation in China through advancingsuch technology as wind electricity generation, cleancoal technology, high efficient natural gas electricitygeneration, or utilization of coal mine methane. Inthis context, the Clean Development Mechanismalso compliments a range of environmental and energypolicies which are strategizing to encourage thesustainable development of China’s economy.
基金supported by the National Natural Science Foundation of China(Grant 12071429).
文摘We investigate the evolution of interfacial gravity-capillary waves propagating along the interface be-tween two dielectric fluids under the action of a horizontal electric field.There is a uniform backgroundflow in each layer,and the relative motion tends to induce Kelvin-Helmholtz(KH)instability.The com-bined effects of gravity,surface tension and electrically induced forces are all taken into account.Underthe short-wave assumption,the expansion and truncation method of Dirichlet-Neumann(DN)operatorsis applied to derive a reduced dynamical model.When KH instability is suppressed linearly by a consider-ably large electric field,our numerical results reveal that in certain regions of parameter space,nonlinearsymmetric traveling wave solutions can be found near the minimum phase speed.Additionally,the de-tailed bifurcation structures are presented together with typical wave profiles.
基金Project supported by the Strategic Priority Research Program(B)of the Chinese Academy of Sciences(CAS)(Grant No.XDB 18010401)the Key Research Program of Frontier Sciences of CAS(Grant No.QYZDB-SSW-DQC009)+2 种基金the“135”Program of the Institute of Geochemistry of CASthe Hundred-Talent Program of CASthe National Natural Science Foundation of China(Grant Nos.41474078,41774099,and 41772042)
文摘The electrical conductivities of single-crystal K-feldspar along three different crystallographic directions are investigated by the Solartron-1260 Impedance/Gain-phase analyzer at 873 K–1223 K and 1.0 GPa–3.0 GPa in a frequency range of 10-1 Hz–106 Hz. The measured electrical conductivity along the ⊥ [001] axis direction decreases with increasing pressure, and the activation energy and activation volume of charge carriers are determined to be 1.04 ± 0.06 e V and 2.51 ± 0.19 cm~3/mole, respectively. The electrical conductivity of K-feldspar is highly anisotropic, and its value along the⊥ [001] axis is approximately three times higher than that along the ⊥ [100] axis. At 2.0 GPa, the diffusion coefficient of ionic potassium is obtained from the electrical conductivity data using the Nernst–Einstein equation. The measured electrical conductivity and calculated diffusion coefficient of potassium suggest that the main conduction mechanism is of ionic conduction, therefore the dominant charge carrier is transferred between normal lattice potassium positions and adjacent interstitial sites along the thermally activated electric field.
文摘The conductivity of non-crystalline fast ionic conductor for B_2O_3-Li_2O-LiCl-Al_2O_3 system is studiedin this paper. The glass structure of this system is discussed by means of infrared spectrum and X-ray fluorescence analysis, and the effects of LiCl and A1_2O_3 on the conductivity of Li^+ in the system are studied as well. Adding Li_2O to the system gives rise to transfer from [BO_3] triangular units to [BO_4] tetrahedral. When Li_2O content exceeds 30mol%, the main group of the glass is the diborate group with more [BO_4] tetrahedra. The adding of LiCl has no obvious influence on the glass structure, and LiCl is under a state dissociated by network, but with the increase of LiCl, the increase of conductivity is obvious. By adding A1_2O_3, the glass can be formed when the room-temperature is cooling down,the conductivity decreases while the conductive activatory energy increases for the glass. The experiment shows that conductivity in the room-temperature is σ= 6.2×10^(-6)Ω^(-1)cm^(-1), when at 300℃, the σ=6.8×10^(-3)Ω^(-1)cm^(-1). The conductive activatory energy computed is 0.6~1.0eV.
基金Project(51222405)supported by the National Natural Science Foundation for Outstanding Young Scholars of ChinaProject(51034002)supported by the National Natural Science Foundation of ChinaProject(120502001)supported by the Fundamental Research Funds for the Central Universities of China
文摘In order to obtain the Al wires with good mechanical properties and high electrical conductivities, conductive wires of Al-0.16 Zr, Al-0.16 Sc, Al-0.12Sc-0.04Zr(mass fraction, %) and pure Al(99.996%) were produced with the diameter of 9.5 mm by continuous rheo-extrusion technology, and the extruded materials were heat treated and analyzed. The results show that the separate additions of 0.16% Sc and 0.16% Zr to pure Al improve the ultimate tensile strength but reduce the electrical conductivity, and the similar trend is found in the Al-0.12Sc-0.04 Zr alloy. After the subsequent heat treatment, the wire with the optimum comprehensive properties is Al-0.12Sc-0.04 Zr alloy, of which the ultimate tensile strength and electrical conductivity reach 160 MPa and 64.03%(IACS), respectively.
文摘Objetives The mechanism for changes in the electrophysiological properties of the atria during rapid pacing induced atrial fibrillation(AF) is not well understood.We aimed to investigate the contribution of intrinsic cardiac autonomic nervous system(ICANS) in chronic atrial electrical remodeling and AF induced by rapid atrial pacing for 4 weeks. Methods Twelve adult mongrel dogs weighing 15 to 20 kg were assigned to two groups;group 1(experimental group,n= 7) and group 2(control group,n =5).All dogs were anesthetized with propofol and mechanically ventilated via endotracheal tubes.The chest was entered via bilateral mini-thoracotomy at the fourth intercostals space.Bipolar pacing electrode was sutured to the right atrial appendage.Four-electrode catheters(Biosense-Webster,Diamond Bar,CA) were secured to allow recording at the right and left atriaum.All tracings from the electrode catheters were amplified and digitally recorded using a computer-based Bard Laboratory System (CR Bard Inc,Billerica,MA).Electrograms were filtered at 50 to 500 Hz.Continuous rapid pacing(600 bpm, 2×threshold[TH]) was performed at the right atrial appendage. Ganglionated Plexi(GP) was localized by applying high frequency stimulation(HFS;20 Hz,0.1ms duration, 0.5 to 4.5 V)with a bipolar stimulation-ablation probe electrode (AtriCure,West Chester,OH).Group1 underwent ablation of bilateral GP and ligament of Marshall followed by 4-week pacing.Group 2 underwent sham operaton without ablation of GP and ligament of Marshall followed by 4-week pacing.The effective refractory period(ERP) and window of vulnerability(WOV) were measured at 2×TH before(baseline) and every week after GP ablation.WOV was defined as the difference between the longest and the shortest coupling interval of the premature stimulus that induced AF.GP consist of the anterior right ganglionated plexi(ARGP) located in the fat pad at the right superior pulmonary vein(RSPV)-atrial junction;the inferior right ganglionated plexi(IRGP) located at the inferior vena cava/right atrial junction;the superior left ganglionated plexi(SLGP) at the left superior pulmonary vein(LSPV) /left atrial junction and the inferior left ganglionated plexi(ILGP) at the left inferior pulmonary vein (LIPV)/left atrial junction.Results Immediately after ablation, the ERP in Group 1 became markedly longer and started to shorten gradually during the first 2 weeks,then stabilized at the 4th week.Compared to Group2,the ERP of Group1 was significantly longer in the first 3 weeks(P【 0.05),but no obvious difference at the 4th week in either the right or left atrium(P】0.05).In Group 1,AF could not be induced(WOV=0)in the first 3 weeks after ablation, and at the 4th week,AF was induced in 2 of 7 dogs.In Group2,WOV progressively widened during the 4-week period. AF could not be induced in 5 of 7 dogs in Group 1 and 1 of 5 dogs in Group 2 during the 4-week pacing period. Conclusions The intrinsic cardiac autonomic nervous system (ICANS) plays an important role in the early stage of atrial electrical remodeling induced by rapid atrial pacing.On the other hand,with time passing by,its effect on the formation of AF decreases gradually,which suggests that ICANS may account for a non-dominant factor in the late stage of the rapid pacing-induced chronic atrial fibrillation.
文摘Electricity pricing is the core of the power institutional reform in China, which is related to not onlyinterests redistribution of all parties, but also health and security of the entire power industry. Only byaccelerating the reform on pricing mechanism can sound development of the power industry be promoted.
基金Projects(2010CB631005,2011CB606105)support by the National Basic Research Program of ChinaProjects(11232008,91216301,11227801,11172151)supported by the National Natural Science Foundation of ChinaProject supported by Tsinghua University Initiative Scientific Research Program
文摘The buckling behavior of a typical structure consisting of a micro constantan wire and a polymer membrane under coupled electrical-mechanical loading was studied. The phenomenon that the constantan wire delaminates from the polymer membrane was observed after unloading. The interfacial toughness of the constantan wire and the polymer membrane was estimated. Moreover, several new instability modes of the constantan wire could be further triggered based on the buckle-driven delamination. After electrical loading and tensile loading, the constantan wire was likely to fracture based on buckling. After electrical loading and compressive loading, the constantan wire was easily folded at the top of the buckling region. On the occasion, the constantan wire buckled towards the inside of the polymer membrane under electrical-compressive loading. The mechanisms of these instability modes were analyzed.
基金supported by the National Natural Science Foundation of China (50671092)
文摘Cu-6%Fe(mass fraction) microcomposites containing(0-0.30)% rare earth elements were prepared by cold drawing and intermediate heat treatments.Microstructure was observed, and mechanical properties and electrical conductivity were measured for alloys at various drawing strain levels.Adding rare earth elements could reduce the size of primary Fe and Cu dendrites of Cu-6%Fe.Ultimate tensile strength increased but electrical conductivity decreased with the increase of drawing strain.Rare earth additions in Cu-6%Fe slightly increased the strength at low strain and effectively improved the conductivity at high strain.Both strain hardening rate and conductivity loss of Cu-6%Fe containing rare earths were reduced at lower strain than Cu-6%Fe.