The cooling water flow rate for hearth of large blast furnaces was calculated by simulation. The results show that the cooling water flow rate shall be above 4 200m3/ h for hearth of large blast furnaces; to meet requ...The cooling water flow rate for hearth of large blast furnaces was calculated by simulation. The results show that the cooling water flow rate shall be above 4 200m3/ h for hearth of large blast furnaces; to meet requirements of the increasing smelting intensity and to ensure the safety at the end of the first campaign,the designed maximum cooling water flow rate should be 5 900m3/ h; according to the flow distribution stability and the calculated resistance loss,hearth cooling stave pipes with the specification of 76 mm × 6 mm shall be adopted to assure the flow velocity in pipes of hearth cooling stave in the range of 1. 9- 2. 3 m / s.展开更多
The personnel in refuge chamber absorb O_2 and exhale CO_2 all the time. Supplying O_2 and removing CO_2 are the basic function of refuge chamber. After disaster occurs, the supply of the compressed air or oxygen for ...The personnel in refuge chamber absorb O_2 and exhale CO_2 all the time. Supplying O_2 and removing CO_2 are the basic function of refuge chamber. After disaster occurs, the supply of the compressed air or oxygen for personnel in refuge chamber is limited. Thus, how to effectively use the compressed air and oxygen and try to improve the time of supply has a great significance. Supplying more oxygen will result in waste, while supplying less oxygen will cause its concentration to be lower, and harm life safety. This research uses the theoretical calculation and numerical simulation, finds critical gas supply for refuge chamber, and illuminates the change law of gas concentration with critical gas supply in refuge chamber,which provides theoretical guidance for effective use of compressed air and oxygen in refuge chamber.展开更多
Assumption about the inner surface of mold is made according to the forming mechanisms of frictional force. The frictional force between billet and mold can be analysed by calculating the thermal shrinkage and the she...Assumption about the inner surface of mold is made according to the forming mechanisms of frictional force. The frictional force between billet and mold can be analysed by calculating the thermal shrinkage and the shearing strength of the meniscus.The model is used to calculate the maximum drawing speed at different conditions. The results are very satisfactory.展开更多
The program to predict the microstructure evolutions during hot strip rolling of C-M n steels has been developed in this paper, BV using this program, the microstructure changes with the processing parameters were ana...The program to predict the microstructure evolutions during hot strip rolling of C-M n steels has been developed in this paper, BV using this program, the microstructure changes with the processing parameters were analysed in detail. showing not only a good agreement of prediction with the measured values, but also entirely possibility to optimize hot strip rolling precess by computer simulation展开更多
In this study,the penetration resistance of a polyurethane elastomer(PUE)/honeycomb aluminum composite structure was investigated.A finite element analysis model was constructed to predict the residual velocity of the...In this study,the penetration resistance of a polyurethane elastomer(PUE)/honeycomb aluminum composite structure was investigated.A finite element analysis model was constructed to predict the residual velocity of the projectile after penetrating the PUE/honeycomb aluminum composite structure,and the accuracy of the model was verified through experiments.Both the residual velocity of the projectile and the failure appearance of the target plate were accurately predicted by the model.In addition,the Cowper-Symonds model was used to describe the material properties of the PUE layer,effectively simulating the damage appearance of the PUE layer after penetration.Subsequently,based on the validated model,three different configurations of the PUE/honeycomb aluminum composite structure were designed on the basis of the original honeycomb aluminum composite structure with a polyurethane elastomer coating,maintaining constant mass of the composite structure,and the ballistic performance was predicted using the finite element model.The anti-penetration performance of the PUE/honeycomb aluminum composite structure was analyzed by examining the velocity changes of the projectile,the energy changes of each component,and the crushing of the honeycomb core layer.Finally,the influence of different projectile shapes on the ultimate ballistic performance of the structure was studied,and the reasons for the influence of warhead shape on the appearance of target plate failure were analyzed.展开更多
High-performance electromagnetic(EM)wave absorbers,covalently bonded reduced graphene oxideFe_(3)O_(4) nanocomposites(rGO-Fe_(3)O_(4)),are synthesized via hydrothermal reaction,amidation reaction and reduction process...High-performance electromagnetic(EM)wave absorbers,covalently bonded reduced graphene oxideFe_(3)O_(4) nanocomposites(rGO-Fe_(3)O_(4)),are synthesized via hydrothermal reaction,amidation reaction and reduction process.The microstructure,surface element composition and morphology of rGO-Fe_(3)O_(4) nanocomposites are characterized and corresponding EM wave absorption properties are analyzed in great detail.It demonstrates that Fe_(3)O_(4) nanoparticles are successfully covalently grafted onto graphene by amide bonds.When the mass ratio of rGO and Fe_(3)O_(4) is 2:1(sample S2),the absorber exhibits the excellent EM wave absorption performance that the maximum reflection loss(RL)reaches up to-48.6 dB at 14.4 GHz,while the effective absorption bandwidth(RL<-10 dB)is 6.32 GHz(11.68-18.0 GHz)with a matching thickness of 2.1 mm.Furthermore,radar cross section(RCS)simulation calculation is also adopted to evaluate the ability of absorbers to scatter EM waves,which proves again that the absorption performance of absorber S2 is optimal.The outstanding EM wave absorption performance is attributed to the synergistic effect between dielectric and magnetic loss,good attenuation ability and excellent impedance matching.Moreover,covalent bonds considered to be carrier channels can facilitate electron migration,adjust EM parameters and then enhance EM wave absorption perfo rmance.This work provides a possible method for preparing efficient EM wave absorbers.展开更多
A metamaterial absorber is computed numerically and measured experimentally in a 150-THz^300-THz range.The measured absorber achieves high absorption rate for both transverse electric（TE） and transverse magnetic（TM...A metamaterial absorber is computed numerically and measured experimentally in a 150-THz^300-THz range.The measured absorber achieves high absorption rate for both transverse electric（TE） and transverse magnetic（TM） polarizations at large angles of incidence.An absorption sensor scheme is proposed based on the measured absorber and the variations of surrounding media.Different surrounding media are applied to the surface of the absorption sensor（including air,water,and glucose solution）.Measured results show that high figure of merit（FOM） values are obtained for different surrounding media.The proposed sensor does not depend on the substrate,which means that it can be transplanted to different sensing platforms conveniently.展开更多
Through on-site defect investigation,special inspection,and finite element simulation calculation of a high-speed upper-span(30+32+30)m prestressed concrete box girder bridge,the overall sliding force of the bridge on...Through on-site defect investigation,special inspection,and finite element simulation calculation of a high-speed upper-span(30+32+30)m prestressed concrete box girder bridge,the overall sliding force of the bridge on the right side of platform 0#is analyzed.In this situation,typical defects such as overall girder slippage,support dislocation,pier column deviation,and pier bottom side cracks have occurred in the overpass.At the same time,combined with simulation calculation analysis,it is interpreted that the 0#and 1#foundation has been damaged at a certain position below the ground line.The occurrence of broken piles has provided a reliable basis for the later reinforcement and maintenance of the bridge and ideas for emergency inspection and analysis of bridges damaged by the same type of landslides.展开更多
In this paper, taking an old mine in Yunnan for example, the design and calculation of the span of its deep ore block room are carried out by using Mathews stability graphic analysis method, theoretical calculation me...In this paper, taking an old mine in Yunnan for example, the design and calculation of the span of its deep ore block room are carried out by using Mathews stability graphic analysis method, theoretical calculation method of roof mechanics model and large-scale three-dimensional nonlinear finite element method software 3D-σ simulation calculation method, which provides guidance for the safety production of the subsequent stopes in the mine.展开更多
This paper reports that the YBa2Cu3-xZnxO7-δ （x = 0-0.4） samples are researched by means of x-ray diffraction, calculations of binding energy, the positron experiments and variations of oxygen content. The results ...This paper reports that the YBa2Cu3-xZnxO7-δ （x = 0-0.4） samples are researched by means of x-ray diffraction, calculations of binding energy, the positron experiments and variations of oxygen content. The results of simulated calculations, positron experiments and variations of oxygen content support the existence of cluster effect. Moreover, it is concluded that the cluster effect is an important factor on suppression of high-Tc cuprate superconductivity and the Tc does not depend on the density of valence electron directly.展开更多
This paper makes a study of some technical and engineering aspects by using C2 ＋ hydrocarbon separation facility at Guangdong Dapeng liquefied natural gas （GDLNG） terminal. In the C2＋ hydrocarbon extraction proces...This paper makes a study of some technical and engineering aspects by using C2 ＋ hydrocarbon separation facility at Guangdong Dapeng liquefied natural gas （GDLNG） terminal. In the C2＋ hydrocarbon extraction process, the cold energy contained in LNG will be utilized. In order to ensure the optimum operating conditions of the temlinal and C2 ＋ hydrocarbon extraction facility by optimizing the current operating processes of the terminal, the C2 ＋ hydrocarbon extraction facility construction plan is proposed. We conducted numerous calculations and simulations using such specific analysis software as PRO II 〈 version 7.0 〉. Additionally available flow data are used to verify the cyclic send-out rates from the terminal, thus establishing the current and future projected load factors. This study is intended to make sure that GDLNG can continue to supply gas via the pipeline system safely without interruptions and most significantly solves the effects of flow fluctuations at the terminal gasification send-out facility on the hydrocarbons extraction, ensuring optimum pipeline operations and ensuring safe and effective means for such C2＋ hydrocarbons extraction process as well. At the same time, the terminal is also in the optimum operation condition. This is very significant to the terminal safety operation and the energy conservation and emission reduction.展开更多
The electrocatalytic CO_(2)reduction reaction(CO_(2)RR)presents a promising approach to achieving carbon neutrality.Currently,anion exchange membranes(AEMs)are widely used in CO_(2)RR electrolyzers.However,the widespr...The electrocatalytic CO_(2)reduction reaction(CO_(2)RR)presents a promising approach to achieving carbon neutrality.Currently,anion exchange membranes(AEMs)are widely used in CO_(2)RR electrolyzers.However,the widespread industrial application of CO_(2)RR electrolyzers faces significant challenges due to the poor alkali resistance,high mass transfer resistance,limited electrode surface area,and high costs associated with conventional AEMs.This paper describes the amplification and stable operation of a horizontal electrolyzer achieved via combining a diaphragm,a double-layer cathode catalyst,and a redesigned flow channel.Furthermore,a new pH measurement device has been proposed to detect the ion concentration on the cathode surface,elucidating the relationship between electrolytic cell components,ion concentration,and Faraday efficiency(FE).The results reveal that the electrolyzer resistance and cell voltage are reduced,and the hydrogen evolution reaction(HER)is effectively reduced due to the high alkali environment and rapid mass transfer enabled by the diaphragm.Furthermore,the uniform flow of electrolytes and rapid desorption of O_(2)bubbles on the anode surface have been achieved through the redesigned flow channel using the computational fluid dynamics(CFD)simulation.Diaphragm-based electrolyzer with a double-layer cathode catalyst structure has been adopted,and the catalytic area has been expanded to 100 cm^(2).After running for 100 h at a current density of 200 m A/cm^(2)in a 1 M KOH solution,the FE_(CO)still exceeds 90%,with a cell voltage of approximately 3 V.展开更多
Power grid simulation calculation iswidely used in fields such as power grid operation,planning,safety defense,and accident inversion,which is one of the fundamental support technologies for power grid operation.At pr...Power grid simulation calculation iswidely used in fields such as power grid operation,planning,safety defense,and accident inversion,which is one of the fundamental support technologies for power grid operation.At present,mainstream software for power grid simulation calculation used by domestic power grid enterprises include PSD Power Tools,Power System Analysis Software Package(PSASP),Advanced Digital Power System Simulator(ADPSS)and so on,which can provide various simulation calculation functions such as power flow calculation,transient stability calculation,short circuit current calculation,etc.But in the process of using these software,various calculation data adjustments still rely entirely on manual experience.This article introduces artificial intelligence technology into power grid simulation calculation and develops an intelligent power system analysis platform which can be used in the simulation for large power grids,achieving the combination of artificial intelligence technology and power grid simulation technology,which can provide technical support for the transformation of power grid simulation and analysis work mode.展开更多
As human improve their ability to fabricate materials, alloys have evolved from simple to complex compositions, accordingly improving functions and performances,promoting the advancements of human civilization. In rec...As human improve their ability to fabricate materials, alloys have evolved from simple to complex compositions, accordingly improving functions and performances,promoting the advancements of human civilization. In recent years, high-entropy alloys（HEAs） have attracted tremendous attention in various fields. With multiple principal components, they inherently possess unique microstructures and many impressive properties, such as high strength and hardness, excellent corrosion resistance, thermal stability, fatigue,fracture, and irradiation resistance, in terms of which they overwhelm the traditional alloys. All these properties have endowed HEAs with many promising potential applications.An in-depth understanding of the essence of HEAs is important to further developing numerous HEAs with better properties and performance in the future. In this paper, we review the recent development of HEAs, and summarize their preparation methods, composition design, phase formation and microstructures, various properties, and modeling and simulation calculations. In addition, the future trends and prospects of HEAs are put forward.展开更多
Accurate battlefield collection plays a crucial role in the end of thewar. How to effectively improve the ability of accurate battlefield collection hasbecome a hot issue of research. However, the existing support for...Accurate battlefield collection plays a crucial role in the end of thewar. How to effectively improve the ability of accurate battlefield collection hasbecome a hot issue of research. However, the existing support force is limited. Tosolve the problem, an improved ant algorithm is applied to the path optimizationproblem of battlefield collection equipment. A model for solving the collectionpath optimization problem of battlefield collection vehicles was designed, andan example was used to simulate calculations. The final results show that thealgorithm is effective and practical,which improves the army’s ability to accuratelycollect equipment in the modern battlefield.展开更多
Ionic liquids(ILs)provide a promising way for efficient absorption and separation of ammonia(NH_(3))due to their extremely low vapor pressures and adjustable structures.However,the understanding of absorption mechanis...Ionic liquids(ILs)provide a promising way for efficient absorption and separation of ammonia(NH_(3))due to their extremely low vapor pressures and adjustable structures.However,the understanding of absorption mechanisms especially in terms of theoretical insights is still not very clear,which is crucial for designing targeted ILs.In this work,a universal method that integrates density functional theory and molecular dynamic simulations was proposed to study the mechanisms of NH_(3)absorption by protic ionic liquids(PILs).The results showed that the NH_(3)absorption performance of the imidazolium-based PILs([BIm][X],X=Tf_(2)N,SCN and NO_(3))is determined by not only the hydrogen bonding between the N atom in NH_(3)and the protic site(H–N_(3))on the cation but also the cation–anion interaction.With the increase in NH_(3)absorption capacity,the hydrogen bonding between[BIm][Tf_(2)N]and NH_(3)changed from orbital dominated to electrostatic dominated,so 3.0 mol NH_(3)per mol IL at 313.15 K and 0.10 MPa was further proved as a threshold for NH_(3)capacity of[BIm][Tf_(2)N]by the Gibbs free energy results,which agrees well with the experimental results.Furthermore,the anions of[BIm][X]could also compete with NH_(3)for interaction with H-N_(3)of the cation,which weakens the interaction between the cation and NH_(3)and then decreases the NH_(3)absorption ability of PILs.This study provides further understanding on NH_(3)absorption mechanisms with ILs,which will guide the design of novel functionalized ILs for NH_(3)separation and recovery.展开更多
文摘The cooling water flow rate for hearth of large blast furnaces was calculated by simulation. The results show that the cooling water flow rate shall be above 4 200m3/ h for hearth of large blast furnaces; to meet requirements of the increasing smelting intensity and to ensure the safety at the end of the first campaign,the designed maximum cooling water flow rate should be 5 900m3/ h; according to the flow distribution stability and the calculated resistance loss,hearth cooling stave pipes with the specification of 76 mm × 6 mm shall be adopted to assure the flow velocity in pipes of hearth cooling stave in the range of 1. 9- 2. 3 m / s.
基金supported by the National Natural Science Foundation of China(Grant Nos.51504251,51404263)the National Natural Science Foundation of Jiangsu of China(Nos.BK20140187,BK20130203)+4 种基金the Fundamental Research Funds for the Central Universities(2015QNB01)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)the Central Universities Special Funds for Fundamental Research Funds of the China University of Mining and Technology(No.2014ZDPY04)the Innovation Team of CUMT(2014QN001)the Natural Science Foundation of Jiangsu Province(No.BK2012571)
文摘The personnel in refuge chamber absorb O_2 and exhale CO_2 all the time. Supplying O_2 and removing CO_2 are the basic function of refuge chamber. After disaster occurs, the supply of the compressed air or oxygen for personnel in refuge chamber is limited. Thus, how to effectively use the compressed air and oxygen and try to improve the time of supply has a great significance. Supplying more oxygen will result in waste, while supplying less oxygen will cause its concentration to be lower, and harm life safety. This research uses the theoretical calculation and numerical simulation, finds critical gas supply for refuge chamber, and illuminates the change law of gas concentration with critical gas supply in refuge chamber,which provides theoretical guidance for effective use of compressed air and oxygen in refuge chamber.
文摘Assumption about the inner surface of mold is made according to the forming mechanisms of frictional force. The frictional force between billet and mold can be analysed by calculating the thermal shrinkage and the shearing strength of the meniscus.The model is used to calculate the maximum drawing speed at different conditions. The results are very satisfactory.
文摘The program to predict the microstructure evolutions during hot strip rolling of C-M n steels has been developed in this paper, BV using this program, the microstructure changes with the processing parameters were analysed in detail. showing not only a good agreement of prediction with the measured values, but also entirely possibility to optimize hot strip rolling precess by computer simulation
基金supported by the National Natural Science Foundation of China(Grant No.11972127).
文摘In this study,the penetration resistance of a polyurethane elastomer(PUE)/honeycomb aluminum composite structure was investigated.A finite element analysis model was constructed to predict the residual velocity of the projectile after penetrating the PUE/honeycomb aluminum composite structure,and the accuracy of the model was verified through experiments.Both the residual velocity of the projectile and the failure appearance of the target plate were accurately predicted by the model.In addition,the Cowper-Symonds model was used to describe the material properties of the PUE layer,effectively simulating the damage appearance of the PUE layer after penetration.Subsequently,based on the validated model,three different configurations of the PUE/honeycomb aluminum composite structure were designed on the basis of the original honeycomb aluminum composite structure with a polyurethane elastomer coating,maintaining constant mass of the composite structure,and the ballistic performance was predicted using the finite element model.The anti-penetration performance of the PUE/honeycomb aluminum composite structure was analyzed by examining the velocity changes of the projectile,the energy changes of each component,and the crushing of the honeycomb core layer.Finally,the influence of different projectile shapes on the ultimate ballistic performance of the structure was studied,and the reasons for the influence of warhead shape on the appearance of target plate failure were analyzed.
基金financially supported by the National Natural Science Foundation of China(No.51672222)the Joint Fund Project-Enterprise-Shaanxi Coal Joint Fund Project(No.2019JLM-32)the Spaceflight Foundation of China(No.2014-HT-XGD)。
文摘High-performance electromagnetic(EM)wave absorbers,covalently bonded reduced graphene oxideFe_(3)O_(4) nanocomposites(rGO-Fe_(3)O_(4)),are synthesized via hydrothermal reaction,amidation reaction and reduction process.The microstructure,surface element composition and morphology of rGO-Fe_(3)O_(4) nanocomposites are characterized and corresponding EM wave absorption properties are analyzed in great detail.It demonstrates that Fe_(3)O_(4) nanoparticles are successfully covalently grafted onto graphene by amide bonds.When the mass ratio of rGO and Fe_(3)O_(4) is 2:1(sample S2),the absorber exhibits the excellent EM wave absorption performance that the maximum reflection loss(RL)reaches up to-48.6 dB at 14.4 GHz,while the effective absorption bandwidth(RL<-10 dB)is 6.32 GHz(11.68-18.0 GHz)with a matching thickness of 2.1 mm.Furthermore,radar cross section(RCS)simulation calculation is also adopted to evaluate the ability of absorbers to scatter EM waves,which proves again that the absorption performance of absorber S2 is optimal.The outstanding EM wave absorption performance is attributed to the synergistic effect between dielectric and magnetic loss,good attenuation ability and excellent impedance matching.Moreover,covalent bonds considered to be carrier channels can facilitate electron migration,adjust EM parameters and then enhance EM wave absorption perfo rmance.This work provides a possible method for preparing efficient EM wave absorbers.
基金Project supported by the National Natural Science Foundation of China(Grant No.11547196)the Key Projects of Sichuan Provincial Department of Education,China(Grant No.15ZA0224)+1 种基金the Project of Sichuan Provincial Key Laboratory of Artificial Intelligence,China(Grant No.2014RYJ01)the Key Plan Projects of Science and Technology of Zigong,China(Grant No.2016CXM05)
文摘A metamaterial absorber is computed numerically and measured experimentally in a 150-THz^300-THz range.The measured absorber achieves high absorption rate for both transverse electric（TE） and transverse magnetic（TM） polarizations at large angles of incidence.An absorption sensor scheme is proposed based on the measured absorber and the variations of surrounding media.Different surrounding media are applied to the surface of the absorption sensor（including air,water,and glucose solution）.Measured results show that high figure of merit（FOM） values are obtained for different surrounding media.The proposed sensor does not depend on the substrate,which means that it can be transplanted to different sensing platforms conveniently.
文摘Through on-site defect investigation,special inspection,and finite element simulation calculation of a high-speed upper-span(30+32+30)m prestressed concrete box girder bridge,the overall sliding force of the bridge on the right side of platform 0#is analyzed.In this situation,typical defects such as overall girder slippage,support dislocation,pier column deviation,and pier bottom side cracks have occurred in the overpass.At the same time,combined with simulation calculation analysis,it is interpreted that the 0#and 1#foundation has been damaged at a certain position below the ground line.The occurrence of broken piles has provided a reliable basis for the later reinforcement and maintenance of the bridge and ideas for emergency inspection and analysis of bridges damaged by the same type of landslides.
文摘In this paper, taking an old mine in Yunnan for example, the design and calculation of the span of its deep ore block room are carried out by using Mathews stability graphic analysis method, theoretical calculation method of roof mechanics model and large-scale three-dimensional nonlinear finite element method software 3D-σ simulation calculation method, which provides guidance for the safety production of the subsequent stopes in the mine.
基金supported by the National Natural Science Foundation of China (Grant No 10647145)The Basic Science Foundation of Henan Educational Bureau of China
文摘This paper reports that the YBa2Cu3-xZnxO7-δ （x = 0-0.4） samples are researched by means of x-ray diffraction, calculations of binding energy, the positron experiments and variations of oxygen content. The results of simulated calculations, positron experiments and variations of oxygen content support the existence of cluster effect. Moreover, it is concluded that the cluster effect is an important factor on suppression of high-Tc cuprate superconductivity and the Tc does not depend on the density of valence electron directly.
文摘This paper makes a study of some technical and engineering aspects by using C2 ＋ hydrocarbon separation facility at Guangdong Dapeng liquefied natural gas （GDLNG） terminal. In the C2＋ hydrocarbon extraction process, the cold energy contained in LNG will be utilized. In order to ensure the optimum operating conditions of the temlinal and C2 ＋ hydrocarbon extraction facility by optimizing the current operating processes of the terminal, the C2 ＋ hydrocarbon extraction facility construction plan is proposed. We conducted numerous calculations and simulations using such specific analysis software as PRO II 〈 version 7.0 〉. Additionally available flow data are used to verify the cyclic send-out rates from the terminal, thus establishing the current and future projected load factors. This study is intended to make sure that GDLNG can continue to supply gas via the pipeline system safely without interruptions and most significantly solves the effects of flow fluctuations at the terminal gasification send-out facility on the hydrocarbons extraction, ensuring optimum pipeline operations and ensuring safe and effective means for such C2＋ hydrocarbons extraction process as well. At the same time, the terminal is also in the optimum operation condition. This is very significant to the terminal safety operation and the energy conservation and emission reduction.
基金supported by the National Key R&D Program of China(2021YFA1500804)the National Natural Science Foundation of China(22121004,22038009,22250008)+2 种基金the Haihe Laboratory of Sustainable Chemical Transformationsthe Program of Introducing Talents of Discipline to Universities(BP0618007)the Xplorer Prize。
文摘The electrocatalytic CO_(2)reduction reaction(CO_(2)RR)presents a promising approach to achieving carbon neutrality.Currently,anion exchange membranes(AEMs)are widely used in CO_(2)RR electrolyzers.However,the widespread industrial application of CO_(2)RR electrolyzers faces significant challenges due to the poor alkali resistance,high mass transfer resistance,limited electrode surface area,and high costs associated with conventional AEMs.This paper describes the amplification and stable operation of a horizontal electrolyzer achieved via combining a diaphragm,a double-layer cathode catalyst,and a redesigned flow channel.Furthermore,a new pH measurement device has been proposed to detect the ion concentration on the cathode surface,elucidating the relationship between electrolytic cell components,ion concentration,and Faraday efficiency(FE).The results reveal that the electrolyzer resistance and cell voltage are reduced,and the hydrogen evolution reaction(HER)is effectively reduced due to the high alkali environment and rapid mass transfer enabled by the diaphragm.Furthermore,the uniform flow of electrolytes and rapid desorption of O_(2)bubbles on the anode surface have been achieved through the redesigned flow channel using the computational fluid dynamics(CFD)simulation.Diaphragm-based electrolyzer with a double-layer cathode catalyst structure has been adopted,and the catalytic area has been expanded to 100 cm^(2).After running for 100 h at a current density of 200 m A/cm^(2)in a 1 M KOH solution,the FE_(CO)still exceeds 90%,with a cell voltage of approximately 3 V.
基金supported by the State Grid Corporation of China‘s project:Research on artificial intelligence analysis technology of available transmission capacity(ATC)of key section under multiple power grid operation modes(5100-202255020A-1-1-ZN).
文摘Power grid simulation calculation iswidely used in fields such as power grid operation,planning,safety defense,and accident inversion,which is one of the fundamental support technologies for power grid operation.At present,mainstream software for power grid simulation calculation used by domestic power grid enterprises include PSD Power Tools,Power System Analysis Software Package(PSASP),Advanced Digital Power System Simulator(ADPSS)and so on,which can provide various simulation calculation functions such as power flow calculation,transient stability calculation,short circuit current calculation,etc.But in the process of using these software,various calculation data adjustments still rely entirely on manual experience.This article introduces artificial intelligence technology into power grid simulation calculation and develops an intelligent power system analysis platform which can be used in the simulation for large power grids,achieving the combination of artificial intelligence technology and power grid simulation technology,which can provide technical support for the transformation of power grid simulation and analysis work mode.
基金supported by the National Natural Science Foundation of China (51471025 and 51671020)
文摘As human improve their ability to fabricate materials, alloys have evolved from simple to complex compositions, accordingly improving functions and performances,promoting the advancements of human civilization. In recent years, high-entropy alloys（HEAs） have attracted tremendous attention in various fields. With multiple principal components, they inherently possess unique microstructures and many impressive properties, such as high strength and hardness, excellent corrosion resistance, thermal stability, fatigue,fracture, and irradiation resistance, in terms of which they overwhelm the traditional alloys. All these properties have endowed HEAs with many promising potential applications.An in-depth understanding of the essence of HEAs is important to further developing numerous HEAs with better properties and performance in the future. In this paper, we review the recent development of HEAs, and summarize their preparation methods, composition design, phase formation and microstructures, various properties, and modeling and simulation calculations. In addition, the future trends and prospects of HEAs are put forward.
文摘Accurate battlefield collection plays a crucial role in the end of thewar. How to effectively improve the ability of accurate battlefield collection hasbecome a hot issue of research. However, the existing support force is limited. Tosolve the problem, an improved ant algorithm is applied to the path optimizationproblem of battlefield collection equipment. A model for solving the collectionpath optimization problem of battlefield collection vehicles was designed, andan example was used to simulate calculations. The final results show that thealgorithm is effective and practical,which improves the army’s ability to accuratelycollect equipment in the modern battlefield.
基金financially supported by the National Key R&D Program of China(2020YFA0710200)the National Natural Science Foundation of China(22122814,21890764 and 21838010)+1 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2018064)the Major Scientific and Technological Innovation Project of Shandong Province of China(2019JZZY010518).
文摘Ionic liquids(ILs)provide a promising way for efficient absorption and separation of ammonia(NH_(3))due to their extremely low vapor pressures and adjustable structures.However,the understanding of absorption mechanisms especially in terms of theoretical insights is still not very clear,which is crucial for designing targeted ILs.In this work,a universal method that integrates density functional theory and molecular dynamic simulations was proposed to study the mechanisms of NH_(3)absorption by protic ionic liquids(PILs).The results showed that the NH_(3)absorption performance of the imidazolium-based PILs([BIm][X],X=Tf_(2)N,SCN and NO_(3))is determined by not only the hydrogen bonding between the N atom in NH_(3)and the protic site(H–N_(3))on the cation but also the cation–anion interaction.With the increase in NH_(3)absorption capacity,the hydrogen bonding between[BIm][Tf_(2)N]and NH_(3)changed from orbital dominated to electrostatic dominated,so 3.0 mol NH_(3)per mol IL at 313.15 K and 0.10 MPa was further proved as a threshold for NH_(3)capacity of[BIm][Tf_(2)N]by the Gibbs free energy results,which agrees well with the experimental results.Furthermore,the anions of[BIm][X]could also compete with NH_(3)for interaction with H-N_(3)of the cation,which weakens the interaction between the cation and NH_(3)and then decreases the NH_(3)absorption ability of PILs.This study provides further understanding on NH_(3)absorption mechanisms with ILs,which will guide the design of novel functionalized ILs for NH_(3)separation and recovery.
