To develop proton-conducting materials with high hydrothermal and acid-base stability and to elucidate the proton-transport mechanism through visualized structural analysis,two new lanthanum phosphite-oxalates with 3D...To develop proton-conducting materials with high hydrothermal and acid-base stability and to elucidate the proton-transport mechanism through visualized structural analysis,two new lanthanum phosphite-oxalates with 3D frameworks,designated as[La(HPO_(3))(C_(2)O_(4))0.5(H_(2)O)_(2)](La‑1)and(C_(6)H_(16)N_(2))(H_(3)O)[La_(2)(H_(2)PO_(3))_(3)(C_(2)O_(4))_(3)(H_(2)O)](La‑2)(C_(6)H_(14)N_(2)=cis-2,6-dimethylpiperazine),were prepared by hydrothermal and solvothermal conduction,respectively.La‑1 was constructed with lanthanum phosphite 2D layers and C_(2)O_(4)^(2-)groups,whereas La‑2 was constructed with lanthanum oxalate 2D layers and H_(2)PO^(3-)groups.Alternating current(AC)impedance spectra indicate that the pro-ton conductivities of both compounds could reach 10^(-4)S·cm^(-1)and remain highly durable at 75℃and 98%of rela-tive humidity(RH).Due to the abundance of H-bonds in La‑2,theσof La‑2 was higher than that of La‑1.La‑1 exhibited excellent water and pH stability.CCDC:2439965,La‑1;443776,La‑2.展开更多
On the surfaces of celestial bodies with no or thin atmospheres,such as the Moon and Mars,the solar wind irradiation process leads to the formation of hydrogen and helium enriched regions in the extraterrestrial soil ...On the surfaces of celestial bodies with no or thin atmospheres,such as the Moon and Mars,the solar wind irradiation process leads to the formation of hydrogen and helium enriched regions in the extraterrestrial soil particles.However,soil particles on the Earth with the similar composition lack such structures and properties.This discrepancy raises a key question whether there is a direct relationship between solar wind irradiation and the alterations in the structure and chemical performance of extraterrestrial materials.To address this question,this work investigates the effects of proton irradiation,simulating solar wind radiation,on the structure and photothermal catalytic properties of the classic catalyst In_(2)O_(3).It reveals that proton irradiation induces structural features in In_(2)O_(3) analogous to those characteristics of solar wind weathering observed in extraterrestrial materials.Furthermore,after proton beam irradiation with an energy of 30 keV and a dose of 3×10^(17) protons·cm^(-2),the methanol production yield of the In_(2)O_(3) catalyst increased to 2.6 times of its preirradiation level,and the methanol selectivity improved to 2.1 times of the original value.This work provides both theoretical and experimental support for the development of high-efficiency,radiation-resistant photothermal catalysts.展开更多
To know about the radiation effects on the super large array 9 k×9 k CCDs used in a space telescope induced by energetic protons,the experiments of the super large array 9 k×9 k charge coupled devices(CCDs)u...To know about the radiation effects on the super large array 9 k×9 k CCDs used in a space telescope induced by energetic protons,the experiments of the super large array 9 k×9 k charge coupled devices(CCDs)used in the space telescope irradiated by 60 MeV and 100 MeV protons are presented.The samples were exposed by 60 MeV and 100 MeV protons at fluences of 5×10^(9)/cm^(2) and 1×10^(10)/cm^(2),respectively.The degradations of the main performance parameters of the super large array CCDs which are paid special attention to the space telescope are investigated.The full well capacity,mean dark current,and the charge transfer inefficiency(CTI)versus proton fluence are presented,which are tested at very low temperature of-85℃.The annealing tests of 168 h were carried out after proton irradiation.The dark images before and after proton irradiation are also presented to compare the image degradation.The degradation mechanisms of the super large array CCDs irradiated by protons are analyzed.The experimental results show that the main performance parameters of the CCDs are degraded after 60 MeV and 100 MeV protons and the degradations induced by 60 MeV protons are larger than that induced by 100 MeV protons.The experimental results of the super large array CCDs irradiated by protons will provide the basic test data support for orbit life assessment of the space telescope.展开更多
The development of highly active catalyst in pH-neutral media for oxygen evolution reaction(OER)is critical in the field of renewable energy storage and conversion.Nevertheless,the slow kinetics of proton-coupled elec...The development of highly active catalyst in pH-neutral media for oxygen evolution reaction(OER)is critical in the field of renewable energy storage and conversion.Nevertheless,the slow kinetics of proton-coupled electron transfer(PCET)hinders the overall OER efficiency.Herein,we report an ionic liquid(IL)modified CoSn(OH)_(6)nanocubes(denoted as CoS-n(OH)_(6)-IL),which could be prepared through a facile strategy.The modified IL would not change the structural character-istics of CoSn(OH)_(6),but could effectively regulate the local proton activity near the active sites.The CoSn(OH)_(6)-IL exhibited higher intrinsic OER performances than the pristine CoSn(OH)_(6)in neutral media.For example,the current density of CoS-n(OH)_(6)-IL at 1.8 V versus reversible hydrogen electrode(RHE)was about 4 times higher than that of CoSn(OH)_(6).According to the pH-dependent kinetic investigations,operando electrochemical impedance spectroscopic,chemical probe tests,and deuterium kinetic isotope effects,the interfacial layer of IL could be utilized as a proton transfer mediator to promote the proton transfer,which enhances the surface coverage of OER intermediates and reduces the activation barrier.Consequent-ly,the sluggish OER kinetics would be efficiently accelerated.This study provides a facile and effective strategy to facilitate the PCET processes and is beneficial to guide the rational design of OER electrocatalysts.展开更多
In this paper,a fusion model based on a long short-term memory(LSTM)neural network and enhanced search ant colony optimization(ENSACO)is proposed to predict the power degradation trend of proton exchange membrane fuel...In this paper,a fusion model based on a long short-term memory(LSTM)neural network and enhanced search ant colony optimization(ENSACO)is proposed to predict the power degradation trend of proton exchange membrane fuel cells(PEMFC).Firstly,the Shapley additive explanations(SHAP)value method is used to select external characteristic parameters with high contributions as inputs for the data-driven approach.Next,a novel swarm optimization algorithm,the enhanced search ant colony optimization,is proposed.This algorithm improves the ant colony optimization(ACO)algorithm based on a reinforcement factor to avoid premature convergence and accelerate the convergence speed.Comparative experiments are set up to compare the performance differences between particle swarm optimization(PSO),ACO,and ENSACO.Finally,a data-driven method based on ENSACO-LSTM is proposed to predict the power degradation trend of PEMFCs.And actual aging data is used to validate the method.The results show that,within a limited number of iterations,the optimization capability of ENSACO is significantly stronger than that of PSO and ACO.Additionally,the prediction accuracy of the ENSACO-LSTM method is greatly improved,with an average increase of approximately 50.58%compared to LSTM,PSO-LSTM,and ACO-LSTM.展开更多
When the proton exchange membrane fuel cell(PEMFC)system is running,there will be a condition that does not require power output for a short time.In order to achieve zero power output under low power consumption,it is...When the proton exchange membrane fuel cell(PEMFC)system is running,there will be a condition that does not require power output for a short time.In order to achieve zero power output under low power consumption,it is necessary to consider the diversity of control targets and the complexity of dynamic models,which brings the challenge of high-precision tracking control of the stack output power and cathode intake flow.For system idle speed control,a modelbased nonlinear control framework is constructed in this paper.Firstly,the nonlinear dynamic model of output power and cathode intake flow is derived.Secondly,a control scheme combining nonlinear extended Kalman filter observer and state feedback controller is designed.Finally,the control scheme is verified on the PEMFC experimental platform and compared with the proportion-integration-differentiation(PID)controller.The experimental results show that the control strategy proposed in this paper can realize the idle speed control of the fuel cell system and achieve the purpose of zero power output.Compared with PID controller,it has faster response speed and better system dynamics.展开更多
Isomers of trans-1,4-Dinitroglycoluril(trans-DINGU) and their 1,3-tautomers are considered within the constraints of B3LYP/6-31ttG(d,p) and B3LYP/CC-PVTZ levels of DFT calculations. Additionally, the interactions of t...Isomers of trans-1,4-Dinitroglycoluril(trans-DINGU) and their 1,3-tautomers are considered within the constraints of B3LYP/6-31ttG(d,p) and B3LYP/CC-PVTZ levels of DFT calculations. Additionally, the interactions of these isomers and proton in vacuum are investigated. The data have revealed that two of the three isomers undergo C — H bond cleavage as the result of interaction with proton in vacuum. The total energies, some structural properties, the calculated IR and UV spectra are discussed.展开更多
The temperature of proton exchange membrane fuel cell stack and the stoichiometric oxygen in cathode have relationship with the performance and life span of fuel cells closely. The thermal coefficients were taken as i...The temperature of proton exchange membrane fuel cell stack and the stoichiometric oxygen in cathode have relationship with the performance and life span of fuel cells closely. The thermal coefficients were taken as important factors affecting the temperature distribution of fuel cells and components. According to the experimental analysis, when the stoichiometric oxygen in cathode is greater than or equal to 1.8, the stack voltage loss is the least. A novel genetic algorithm was developed to identify and optimize the variables in dynamic thermal model of proton exchange membrane fuel cell stack, making the outputs of temperature model approximate to the actual temperature, and ensuring that the maximal error is less than 1 ℃. At the same time, the optimum region of stoichiometric oxygen is obtained, which is in the range of 1.8-2.2 and accords with the experimental analysis results. The simulation and experimental results show the effectiveness of the proposed algorithm.展开更多
Spherical Ni（OH）2 particles were prepared by an aqueous solution precipitation route. The structure of spherical Ni（OH）2 was investigated by scanning electron microscopy and transmission electron microscopy and co...Spherical Ni（OH）2 particles were prepared by an aqueous solution precipitation route. The structure of spherical Ni（OH）2 was investigated by scanning electron microscopy and transmission electron microscopy and compared with that of traditional Ni（OH）2. The results show that the spherical nickel hydroxide consists of （Ni（OH）2） spheres with a reticulate structure of platelet-like, which is almost arranged radially and the crystalline grains intervene and connect with each other to form a three-dimensional net. The spherical Ni（OH）2 particle is full of pores, crannies between cleave planes. It is supposed that this structure is beneficial to the structural stability for the spherical particles during the charge/discharge processes and can improve the cycle life of the electrode; the pores and the crannies in spherical particles can shorten the proton diffusion distance and speed its velocity, which may result in that the local polarization is lowered. The electrochemical performances of the spherical Ni（OH）2 are improved by enhancing the conducting properties of the crystalline lattice due to its quick proton diffusion.展开更多
Proton exchange membrane fuel cell (PEMFC) stack temperature and cathode stoichiometric oxygen are very important control parameters. The performance and lifespan of PEMFC stack are greatly dependent on the parameters...Proton exchange membrane fuel cell (PEMFC) stack temperature and cathode stoichiometric oxygen are very important control parameters. The performance and lifespan of PEMFC stack are greatly dependent on the parameters. So, in order to improve the performance index, tight control of two parameters within a given range and reducing their fluctuation are indispensable. However, control-oriented models and control strategies are very weak junctures in the PEMFC development. A predictive control algorithm was presented based on their model established by input-output data and operating experiences. It adjusts the operating temperature to 80 ℃. At the same time, the optimized region of stoichiometric oxygen is kept between 1.8?2.2. Furthermore, the control algorithm adjusts the variants quickly to the destination value and makes the fluctuation of the variants the least. According to the test results, compared with traditional fuzzy and PID controllers, the designed controller shows much better performance.展开更多
A neural network model and fuzzy neural network controller was designed to control the inner impedance of a proton exchange membrane fuel cell (PEMFC) stack. A radial basis function (RBF) neural network model was trai...A neural network model and fuzzy neural network controller was designed to control the inner impedance of a proton exchange membrane fuel cell (PEMFC) stack. A radial basis function (RBF) neural network model was trained by the input-output data of impedance. A fuzzy neural network controller was designed to control the impedance response. The RBF neural network model was used to test the fuzzy neural network controller. The results show that the RBF model output can imitate actual output well, the maximal error is not beyond 20 m-, the training time is about 1 s by using 20 neurons, and the mean squared errors is 141.9 m-2. The impedance of the PEMFC stack is controlled within the optimum range when the load changes, and the adjustive time is about 3 min.展开更多
When the diffusion exist ,we investigate the proton-proton reaction with the linear stability analysis method and find the reaction is atabie. When allowing for both diffusion and convection, we still get the conclusi...When the diffusion exist ,we investigate the proton-proton reaction with the linear stability analysis method and find the reaction is atabie. When allowing for both diffusion and convection, we still get the conclusion that PPI reaction is stable with the generating-function method.展开更多
The composites of certain nitramine type explosives,TETRYL,RDX and EDNA,with proton in vacuum have been considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p)(restricted and ...The composites of certain nitramine type explosives,TETRYL,RDX and EDNA,with proton in vacuum have been considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p)(restricted and unrestricted).The results indicate that unexpectedly hydrogen molecule production occurs by the interaction of proton and a hydrogen of CH3(TETRYL)and CH2(RDX and EDNA)groups.As a result,a carbocation is generated on the explosive molecules.Thereafter,TETRYL which potentially has many protonation sites were investigated in more detail in vacuum and aqueous conditions.The data reveals that the composite system(TETRYL+proton)is less stable than TETRYL protonated on nitramine NH or oxygen of the nitro groups.展开更多
The stoichiometric ratios and related regimes, which can promote anti-flooding of polymer electrolyte membrane fuel cell （PEMFC） with in-plate adverse-flow flow-field （IPAF）, were investigated. Two flow combinatio...The stoichiometric ratios and related regimes, which can promote anti-flooding of polymer electrolyte membrane fuel cell （PEMFC） with in-plate adverse-flow flow-field （IPAF）, were investigated. Two flow combinations, which are the simple and complex adverse-flow between plates （ABP） that can be realized by IPAF, were employed. Constant stoichiometric ratios examination indicates that the complex ABP could improve anti-flooding of PEMFC better in the medium （greater than 200 mA/cm2 and less than 1 000 mA/cm2） and high （greater than 1 000 mA/cm2） current densities than the simple ABP. More stoichiometric ratios were introduced to find the cathode critical stoichiometry. Under the condition of cathode critical stoichiometry, the maximal local relative humidity of both electrodes of complex ABP is equal to 100% and below while the anti-flooding of the cathode of simple ABP is not satisfactory in the medium and high current densities. Further study shows that the mechanism of fuel cell, which is the imerdependence between the electrodes effect, can make significant contribution to anti-flooding.展开更多
文摘To develop proton-conducting materials with high hydrothermal and acid-base stability and to elucidate the proton-transport mechanism through visualized structural analysis,two new lanthanum phosphite-oxalates with 3D frameworks,designated as[La(HPO_(3))(C_(2)O_(4))0.5(H_(2)O)_(2)](La‑1)and(C_(6)H_(16)N_(2))(H_(3)O)[La_(2)(H_(2)PO_(3))_(3)(C_(2)O_(4))_(3)(H_(2)O)](La‑2)(C_(6)H_(14)N_(2)=cis-2,6-dimethylpiperazine),were prepared by hydrothermal and solvothermal conduction,respectively.La‑1 was constructed with lanthanum phosphite 2D layers and C_(2)O_(4)^(2-)groups,whereas La‑2 was constructed with lanthanum oxalate 2D layers and H_(2)PO^(3-)groups.Alternating current(AC)impedance spectra indicate that the pro-ton conductivities of both compounds could reach 10^(-4)S·cm^(-1)and remain highly durable at 75℃and 98%of rela-tive humidity(RH).Due to the abundance of H-bonds in La‑2,theσof La‑2 was higher than that of La‑1.La‑1 exhibited excellent water and pH stability.CCDC:2439965,La‑1;443776,La‑2.
基金National Key Research and Development Program of China(2020YFA0710302)The Major Research Plan of the National Natural Science Foundation of China(91963206)+2 种基金The National Natural Science Foundation of China(52072169,51972164,51972167,22279053)The Fundamental Research Funds for the Central Universities(14380193)The Program for Guangdong Introducing Innovative and Entrepreneurial Teams(2019ZT08L101).
文摘On the surfaces of celestial bodies with no or thin atmospheres,such as the Moon and Mars,the solar wind irradiation process leads to the formation of hydrogen and helium enriched regions in the extraterrestrial soil particles.However,soil particles on the Earth with the similar composition lack such structures and properties.This discrepancy raises a key question whether there is a direct relationship between solar wind irradiation and the alterations in the structure and chemical performance of extraterrestrial materials.To address this question,this work investigates the effects of proton irradiation,simulating solar wind radiation,on the structure and photothermal catalytic properties of the classic catalyst In_(2)O_(3).It reveals that proton irradiation induces structural features in In_(2)O_(3) analogous to those characteristics of solar wind weathering observed in extraterrestrial materials.Furthermore,after proton beam irradiation with an energy of 30 keV and a dose of 3×10^(17) protons·cm^(-2),the methanol production yield of the In_(2)O_(3) catalyst increased to 2.6 times of its preirradiation level,and the methanol selectivity improved to 2.1 times of the original value.This work provides both theoretical and experimental support for the development of high-efficiency,radiation-resistant photothermal catalysts.
基金The National Science Foundation of China(U2167208,11875223)Natural Science Basic Research Program of Shaanxi(2024JC-JCQN)The Foundation of State Key Laboratory of China(NKLIPR2320)。
文摘To know about the radiation effects on the super large array 9 k×9 k CCDs used in a space telescope induced by energetic protons,the experiments of the super large array 9 k×9 k charge coupled devices(CCDs)used in the space telescope irradiated by 60 MeV and 100 MeV protons are presented.The samples were exposed by 60 MeV and 100 MeV protons at fluences of 5×10^(9)/cm^(2) and 1×10^(10)/cm^(2),respectively.The degradations of the main performance parameters of the super large array CCDs which are paid special attention to the space telescope are investigated.The full well capacity,mean dark current,and the charge transfer inefficiency(CTI)versus proton fluence are presented,which are tested at very low temperature of-85℃.The annealing tests of 168 h were carried out after proton irradiation.The dark images before and after proton irradiation are also presented to compare the image degradation.The degradation mechanisms of the super large array CCDs irradiated by protons are analyzed.The experimental results show that the main performance parameters of the CCDs are degraded after 60 MeV and 100 MeV protons and the degradations induced by 60 MeV protons are larger than that induced by 100 MeV protons.The experimental results of the super large array CCDs irradiated by protons will provide the basic test data support for orbit life assessment of the space telescope.
基金supported by the National Natural Science Foundation of China(22209040,22202063).
文摘The development of highly active catalyst in pH-neutral media for oxygen evolution reaction(OER)is critical in the field of renewable energy storage and conversion.Nevertheless,the slow kinetics of proton-coupled electron transfer(PCET)hinders the overall OER efficiency.Herein,we report an ionic liquid(IL)modified CoSn(OH)_(6)nanocubes(denoted as CoS-n(OH)_(6)-IL),which could be prepared through a facile strategy.The modified IL would not change the structural character-istics of CoSn(OH)_(6),but could effectively regulate the local proton activity near the active sites.The CoSn(OH)_(6)-IL exhibited higher intrinsic OER performances than the pristine CoSn(OH)_(6)in neutral media.For example,the current density of CoS-n(OH)_(6)-IL at 1.8 V versus reversible hydrogen electrode(RHE)was about 4 times higher than that of CoSn(OH)_(6).According to the pH-dependent kinetic investigations,operando electrochemical impedance spectroscopic,chemical probe tests,and deuterium kinetic isotope effects,the interfacial layer of IL could be utilized as a proton transfer mediator to promote the proton transfer,which enhances the surface coverage of OER intermediates and reduces the activation barrier.Consequent-ly,the sluggish OER kinetics would be efficiently accelerated.This study provides a facile and effective strategy to facilitate the PCET processes and is beneficial to guide the rational design of OER electrocatalysts.
基金Supported by the Major Science and Technology Project of Jilin Province(20220301010GX)the International Scientific and Technological Cooperation(20240402071GH).
文摘In this paper,a fusion model based on a long short-term memory(LSTM)neural network and enhanced search ant colony optimization(ENSACO)is proposed to predict the power degradation trend of proton exchange membrane fuel cells(PEMFC).Firstly,the Shapley additive explanations(SHAP)value method is used to select external characteristic parameters with high contributions as inputs for the data-driven approach.Next,a novel swarm optimization algorithm,the enhanced search ant colony optimization,is proposed.This algorithm improves the ant colony optimization(ACO)algorithm based on a reinforcement factor to avoid premature convergence and accelerate the convergence speed.Comparative experiments are set up to compare the performance differences between particle swarm optimization(PSO),ACO,and ENSACO.Finally,a data-driven method based on ENSACO-LSTM is proposed to predict the power degradation trend of PEMFCs.And actual aging data is used to validate the method.The results show that,within a limited number of iterations,the optimization capability of ENSACO is significantly stronger than that of PSO and ACO.Additionally,the prediction accuracy of the ENSACO-LSTM method is greatly improved,with an average increase of approximately 50.58%compared to LSTM,PSO-LSTM,and ACO-LSTM.
基金Supported by the Major Science and Technology Projects in Jilin Province and Changchun City(20220301010GX).
文摘When the proton exchange membrane fuel cell(PEMFC)system is running,there will be a condition that does not require power output for a short time.In order to achieve zero power output under low power consumption,it is necessary to consider the diversity of control targets and the complexity of dynamic models,which brings the challenge of high-precision tracking control of the stack output power and cathode intake flow.For system idle speed control,a modelbased nonlinear control framework is constructed in this paper.Firstly,the nonlinear dynamic model of output power and cathode intake flow is derived.Secondly,a control scheme combining nonlinear extended Kalman filter observer and state feedback controller is designed.Finally,the control scheme is verified on the PEMFC experimental platform and compared with the proportion-integration-differentiation(PID)controller.The experimental results show that the control strategy proposed in this paper can realize the idle speed control of the fuel cell system and achieve the purpose of zero power output.Compared with PID controller,it has faster response speed and better system dynamics.
文摘Isomers of trans-1,4-Dinitroglycoluril(trans-DINGU) and their 1,3-tautomers are considered within the constraints of B3LYP/6-31ttG(d,p) and B3LYP/CC-PVTZ levels of DFT calculations. Additionally, the interactions of these isomers and proton in vacuum are investigated. The data have revealed that two of the three isomers undergo C — H bond cleavage as the result of interaction with proton in vacuum. The total energies, some structural properties, the calculated IR and UV spectra are discussed.
基金Project (2003AA517020) supported by the National High-Technology Research Plan of China
文摘The temperature of proton exchange membrane fuel cell stack and the stoichiometric oxygen in cathode have relationship with the performance and life span of fuel cells closely. The thermal coefficients were taken as important factors affecting the temperature distribution of fuel cells and components. According to the experimental analysis, when the stoichiometric oxygen in cathode is greater than or equal to 1.8, the stack voltage loss is the least. A novel genetic algorithm was developed to identify and optimize the variables in dynamic thermal model of proton exchange membrane fuel cell stack, making the outputs of temperature model approximate to the actual temperature, and ensuring that the maximal error is less than 1 ℃. At the same time, the optimum region of stoichiometric oxygen is obtained, which is in the range of 1.8-2.2 and accords with the experimental analysis results. The simulation and experimental results show the effectiveness of the proposed algorithm.
基金Project(50134020) supported by the National Natural Science Foundation of China
文摘Spherical Ni（OH）2 particles were prepared by an aqueous solution precipitation route. The structure of spherical Ni（OH）2 was investigated by scanning electron microscopy and transmission electron microscopy and compared with that of traditional Ni（OH）2. The results show that the spherical nickel hydroxide consists of （Ni（OH）2） spheres with a reticulate structure of platelet-like, which is almost arranged radially and the crystalline grains intervene and connect with each other to form a three-dimensional net. The spherical Ni（OH）2 particle is full of pores, crannies between cleave planes. It is supposed that this structure is beneficial to the structural stability for the spherical particles during the charge/discharge processes and can improve the cycle life of the electrode; the pores and the crannies in spherical particles can shorten the proton diffusion distance and speed its velocity, which may result in that the local polarization is lowered. The electrochemical performances of the spherical Ni（OH）2 are improved by enhancing the conducting properties of the crystalline lattice due to its quick proton diffusion.
基金Project (2003AA517020) supported by the National High-Tech Research and Development Program of China
文摘Proton exchange membrane fuel cell (PEMFC) stack temperature and cathode stoichiometric oxygen are very important control parameters. The performance and lifespan of PEMFC stack are greatly dependent on the parameters. So, in order to improve the performance index, tight control of two parameters within a given range and reducing their fluctuation are indispensable. However, control-oriented models and control strategies are very weak junctures in the PEMFC development. A predictive control algorithm was presented based on their model established by input-output data and operating experiences. It adjusts the operating temperature to 80 ℃. At the same time, the optimized region of stoichiometric oxygen is kept between 1.8?2.2. Furthermore, the control algorithm adjusts the variants quickly to the destination value and makes the fluctuation of the variants the least. According to the test results, compared with traditional fuzzy and PID controllers, the designed controller shows much better performance.
基金Project(2003AA517020) supported by the National High Technology Research and Development Program of China
文摘A neural network model and fuzzy neural network controller was designed to control the inner impedance of a proton exchange membrane fuel cell (PEMFC) stack. A radial basis function (RBF) neural network model was trained by the input-output data of impedance. A fuzzy neural network controller was designed to control the impedance response. The RBF neural network model was used to test the fuzzy neural network controller. The results show that the RBF model output can imitate actual output well, the maximal error is not beyond 20 m-, the training time is about 1 s by using 20 neurons, and the mean squared errors is 141.9 m-2. The impedance of the PEMFC stack is controlled within the optimum range when the load changes, and the adjustive time is about 3 min.
文摘When the diffusion exist ,we investigate the proton-proton reaction with the linear stability analysis method and find the reaction is atabie. When allowing for both diffusion and convection, we still get the conclusion that PPI reaction is stable with the generating-function method.
文摘The composites of certain nitramine type explosives,TETRYL,RDX and EDNA,with proton in vacuum have been considered within the constraints of density functional theory at the level of B3LYP/6-31++G(d,p)(restricted and unrestricted).The results indicate that unexpectedly hydrogen molecule production occurs by the interaction of proton and a hydrogen of CH3(TETRYL)and CH2(RDX and EDNA)groups.As a result,a carbocation is generated on the explosive molecules.Thereafter,TETRYL which potentially has many protonation sites were investigated in more detail in vacuum and aqueous conditions.The data reveals that the composite system(TETRYL+proton)is less stable than TETRYL protonated on nitramine NH or oxygen of the nitro groups.
基金Project(20976095) supported by the National Natural Science Foundation of ChinaProject(2012CB215500) supported by the National Basic Research Program of China+1 种基金Project(20090002110074) supported by the Specialized Research Fund for the Doctoral Program of Higher Education, ChinaProjects(2012AA1106012, 2012AA053402) supported by the National Hi-tech Research and Development Program of China
文摘The stoichiometric ratios and related regimes, which can promote anti-flooding of polymer electrolyte membrane fuel cell （PEMFC） with in-plate adverse-flow flow-field （IPAF）, were investigated. Two flow combinations, which are the simple and complex adverse-flow between plates （ABP） that can be realized by IPAF, were employed. Constant stoichiometric ratios examination indicates that the complex ABP could improve anti-flooding of PEMFC better in the medium （greater than 200 mA/cm2 and less than 1 000 mA/cm2） and high （greater than 1 000 mA/cm2） current densities than the simple ABP. More stoichiometric ratios were introduced to find the cathode critical stoichiometry. Under the condition of cathode critical stoichiometry, the maximal local relative humidity of both electrodes of complex ABP is equal to 100% and below while the anti-flooding of the cathode of simple ABP is not satisfactory in the medium and high current densities. Further study shows that the mechanism of fuel cell, which is the imerdependence between the electrodes effect, can make significant contribution to anti-flooding.
