Aiming at the problem of poor system dynamic performance caused by low parameter matching in the coordinated control of Stirling engine and linear generator in the starting stage control of free piston Stirling linear...Aiming at the problem of poor system dynamic performance caused by low parameter matching in the coordinated control of Stirling engine and linear generator in the starting stage control of free piston Stirling linear generator system,a joint control method of free piston Stirling permanent magnet synchronous linear generator system based on field orientation control is proposed,based on the theoretical derivation of the mathematical model of the system and the principle of controller parameters setting,the simulation experiments of the system starting stage under several Stirling engine working conditions are carried out under simulation.The experimental results show that the stability and rapidity of the system are improved,and the dynamic response speed of generator parameters under different working conditions is accelerated,what fully verifies the correctness and effectiveness of the method.It provides an effective way to improve the control performance of the system and stabilize the power generation operation.展开更多
Zeolitic Imidazolate Framework-8(ZIF-8)material was prepared by chemical precipitation method.The microstructure and physical properties of the as-prepared samples were characterized by XRD,BET,FESEM and UV spectropho...Zeolitic Imidazolate Framework-8(ZIF-8)material was prepared by chemical precipitation method.The microstructure and physical properties of the as-prepared samples were characterized by XRD,BET,FESEM and UV spectrophotometer.The self-made four-channel measurement device was used to test the gas sensitivity of ZIF-8 material toward ethanol gas under photo-thermal synergistic excitation.The results showed that the sample was typical ZIF-8(E_(g)=4.96 eV)with a regular dodecahedron shape and the specific surface is up to 1793 m^(2)/g.The as-prepared ZIF-8 has a gas response value of 55.04 to 100 ppm ethanol at 75℃ and it shows good gas sensing selectivity and repeated stability.The excellent gas sensitivity can be attributed to the increase of free electron concentration in the ZIF-8 conduction band by photo-thermal synergistic excitation,and the large specific surface area of ZIF-8 material provides more active sites for gas-solid surface reaction.The reaction mechanism of ZIF-8 material under multi-field excitation was also discussed.展开更多
Tin oxide（SnO2） hollow microspheres with narrow size distribution were prepared by a facile one-pot microwave-assisted spray pyrolysis method. The effect of temperature on microstructural and optical properties was ...Tin oxide（SnO2） hollow microspheres with narrow size distribution were prepared by a facile one-pot microwave-assisted spray pyrolysis method. The effect of temperature on microstructural and optical properties was investigated by X-ray diffraction（XRD）, scanning electron microscope（SEM）, high resolution transmission electron microscope（HRTEM）, and UV-Vis spectrophotometer（UV-Vis）, respectively.The SnO2 particles obtained at and above 700？C are tetragonal rutile structure with high purity and smooth surface morphology, which consist of well-interconnected SnO2 nanocrystallines and the shell thickness was about 26 nm. UV-Vis absorption values were quite low in visible light region and high in ultraviolet region, indicating the possible utilization for optical purpose of the as-prepared SnO2. The band gaps were 3.88 and 4.07 e V for SnO2 synthesized at 700 and 800？C, respectively. As compared to traditional electrical heating or flame modes, microwave heating introduced here demonstrates a highefficiency, environmentally benign, and time-and energy-saving technology to synthesize advanced powders.展开更多
Process reinforcement research was carried out in Y-junction slug flow microreactors under variable conditions,using EHEHPA(2-ethylhexyl phosphonic acid mono-2-ethylhexyl)to extract yttrium(Ⅲ)from hydrochloric acid s...Process reinforcement research was carried out in Y-junction slug flow microreactors under variable conditions,using EHEHPA(2-ethylhexyl phosphonic acid mono-2-ethylhexyl)to extract yttrium(Ⅲ)from hydrochloric acid solution.The influence of pH and flow rate on the extraction-reaction efficiency,slug size,mass transfer performance was assessed.The experimental results showed that maximum extraction-reaction efficiency of 91.85%can be achieved in the smallest microreactor(residence time is 11.25 s),which was significantly higher than traditional extraction requiring more than 10 min.The slug length tended to decrease with the increase of pH and flow rate.Volumetric mass transfer coefficients for the slug flow microreactors were found to be in the range of 1.39×10^-1-1.642s^-1 that is several orders of magnitude higher as compared to traditional extractors,which testified the beneficial effects of Y-junction slug flow microreactor.Significant mass transfer reinforcement has prompted the use of microreactor as a suitable alternative to traditional extractors,which can advantageously improve the economic and environmental development of mineral processing.展开更多
基金This work was supported in part by the National Natural Science Foundation of China under Grant 51767018,in part by the Scientific research project of Education Department of Gansu Province under Grant 2017A-012.
文摘Aiming at the problem of poor system dynamic performance caused by low parameter matching in the coordinated control of Stirling engine and linear generator in the starting stage control of free piston Stirling linear generator system,a joint control method of free piston Stirling permanent magnet synchronous linear generator system based on field orientation control is proposed,based on the theoretical derivation of the mathematical model of the system and the principle of controller parameters setting,the simulation experiments of the system starting stage under several Stirling engine working conditions are carried out under simulation.The experimental results show that the stability and rapidity of the system are improved,and the dynamic response speed of generator parameters under different working conditions is accelerated,what fully verifies the correctness and effectiveness of the method.It provides an effective way to improve the control performance of the system and stabilize the power generation operation.
基金supported by the National Natural Science Foundation of China(No.51864028)the Yunnan Province Science and Technology Major Project for Materials Genetic Engineering of Rare and Precious Metal(No.202002AB080001)+2 种基金the Yunnan Province Funds for Distinguished Young Scientists,(No.2019FJ005)the Science Research Foundation of Yunnan Provincial Education Department(No.2022J0441)the Sichuan Science and Technology Program(No.22QYCX0097)。
文摘Zeolitic Imidazolate Framework-8(ZIF-8)material was prepared by chemical precipitation method.The microstructure and physical properties of the as-prepared samples were characterized by XRD,BET,FESEM and UV spectrophotometer.The self-made four-channel measurement device was used to test the gas sensitivity of ZIF-8 material toward ethanol gas under photo-thermal synergistic excitation.The results showed that the sample was typical ZIF-8(E_(g)=4.96 eV)with a regular dodecahedron shape and the specific surface is up to 1793 m^(2)/g.The as-prepared ZIF-8 has a gas response value of 55.04 to 100 ppm ethanol at 75℃ and it shows good gas sensing selectivity and repeated stability.The excellent gas sensitivity can be attributed to the increase of free electron concentration in the ZIF-8 conduction band by photo-thermal synergistic excitation,and the large specific surface area of ZIF-8 material provides more active sites for gas-solid surface reaction.The reaction mechanism of ZIF-8 material under multi-field excitation was also discussed.
基金supported by the project from the National Natural Science Foundation of China(Nos.51264015 and 51404116)the Yunnan Provincial Science and Technology Innovation Talents Scheme-Technological Leading Talent(No.2013HA002)
文摘Tin oxide（SnO2） hollow microspheres with narrow size distribution were prepared by a facile one-pot microwave-assisted spray pyrolysis method. The effect of temperature on microstructural and optical properties was investigated by X-ray diffraction（XRD）, scanning electron microscope（SEM）, high resolution transmission electron microscope（HRTEM）, and UV-Vis spectrophotometer（UV-Vis）, respectively.The SnO2 particles obtained at and above 700？C are tetragonal rutile structure with high purity and smooth surface morphology, which consist of well-interconnected SnO2 nanocrystallines and the shell thickness was about 26 nm. UV-Vis absorption values were quite low in visible light region and high in ultraviolet region, indicating the possible utilization for optical purpose of the as-prepared SnO2. The band gaps were 3.88 and 4.07 e V for SnO2 synthesized at 700 and 800？C, respectively. As compared to traditional electrical heating or flame modes, microwave heating introduced here demonstrates a highefficiency, environmentally benign, and time-and energy-saving technology to synthesize advanced powders.
基金support from the following program:Yunan Ten Thousand Talents Plan Young&Elite Tal-ents Project(No.YNWR-QNBJ-2018-323).
文摘Process reinforcement research was carried out in Y-junction slug flow microreactors under variable conditions,using EHEHPA(2-ethylhexyl phosphonic acid mono-2-ethylhexyl)to extract yttrium(Ⅲ)from hydrochloric acid solution.The influence of pH and flow rate on the extraction-reaction efficiency,slug size,mass transfer performance was assessed.The experimental results showed that maximum extraction-reaction efficiency of 91.85%can be achieved in the smallest microreactor(residence time is 11.25 s),which was significantly higher than traditional extraction requiring more than 10 min.The slug length tended to decrease with the increase of pH and flow rate.Volumetric mass transfer coefficients for the slug flow microreactors were found to be in the range of 1.39×10^-1-1.642s^-1 that is several orders of magnitude higher as compared to traditional extractors,which testified the beneficial effects of Y-junction slug flow microreactor.Significant mass transfer reinforcement has prompted the use of microreactor as a suitable alternative to traditional extractors,which can advantageously improve the economic and environmental development of mineral processing.
