In this article, a new variable leakage flux reverse salient-pole motor(VLF-RSPM) is raised to widen the speed range. The innovation is to realize both reverse salient-pole characteristics and variable leakage flux ch...In this article, a new variable leakage flux reverse salient-pole motor(VLF-RSPM) is raised to widen the speed range. The innovation is to realize both reverse salient-pole characteristics and variable leakage flux characteristics by using a method of adding magnetic bridges and magnetic barriers. Firstly, the evolution of the topological structure and working principle of the motor are introduced. Secondly, based on 2D Finite Element Analysis(FEA), the electromagnetic properties and noise of the motor are analyzed in detail, and the electromagnetic properties are contrasted with that of the conventional V-type synchronous motor(CVTSM). The results show that VLF-RSPM has the advantages of small torque ripple, strong magnetic weakening ability, low noise, high efficiency, and low risk of permanent magnet demagnetization under different conditions. In addition, it is verified that the proposed motor extends the speed range.展开更多
Stainless steels are used in a wide range of complex environments due to their excellent corrosion resistance.Multiphase stainless steels can offer an excellent combination of strength,toughness and corrosion resistan...Stainless steels are used in a wide range of complex environments due to their excellent corrosion resistance.Multiphase stainless steels can offer an excellent combination of strength,toughness and corrosion resistance due to the coexistence of different microstructures.The microstructure and mechanical properties of a novel cast multiphase stainless steel,composed of martensite,ferrite,and austenite,were investigated following appropriate heat treatment processes:solution treatment at 1,050℃ for 0.5 h followed by water quenching to room temperature,and aging treatment at 500℃ for 4 h followed by water quenching to room temperature.Results show reversed austenite is formed by diffusion of Ni element during aging process,and the enrichment of Ni atoms directly determines the mechanical stability of austenite.The austenite with a lower Ni content undergoes a martensitic transformation during plastic deformation.The tensile strength of the specimen exceeds 1,100 MPa and the elongation exceeds 24%after solid solution,and further increases to 1,247 MPa and 25%after aging treatment.This enhancement is due to the TRIP effect of austenite and the precipitation of the nanoscale G-phase pinning dislocations in ferrite and martensite.展开更多
Ni/n-SiO2 composite coating was electrodeposited by brush-plating with pulse-reverse current（RC）. The morphology, hardness, and tribological properties of the coating were investigated and compared with those of Ni ...Ni/n-SiO2 composite coating was electrodeposited by brush-plating with pulse-reverse current（RC）. The morphology, hardness, and tribological properties of the coating were investigated and compared with those of Ni and composite coatings electrodeposited with direct current（DC）. The results indicate that Ni/n-SiO2 composite coating electrodeposited by RC, because of RC and the nano powders, has denser coating, finer crystal grains, higher hardness（HV650.0, nearly 1.5 times higher than that of Ni coating electrodeposited by DC） and lower friction coefficient（nearly 0.62）, as a result, in the wearing experiment, the Ni/n-SiO2 composite coating electrodeposited by RC has the least worn loss. So this kind of coating has better wear resistance. And RC electro brush-plating can be used as a new technology of brush-plating in the area of wear resistance.展开更多
Based on the study of a new type of conducting polymer poly （3,4-ethylenedioxythiophene） （PEDOT）,we focussed on the preparation and characteristics of PEDOT nanoparticles made by reversed micelle method.Moreover,w...Based on the study of a new type of conducting polymer poly （3,4-ethylenedioxythiophene） （PEDOT）,we focussed on the preparation and characteristics of PEDOT nanoparticles made by reversed micelle method.Moreover,we deeply investigated the optical,electrical and the thermal stability of PEDOT nanoparticles.The main results are as follows： the small-sized PEDOT nanoparticles were prepared and utilized by different methods,such as ultraviolet/visible （UV-Vis） spectroscopy,Fourier-transform infrared （FT- IR） spectrum,scanning electron microscopy（SEM） and so on.The results show that the amount of oxidizer,ultrasonic treatment,polymerizing temperature and doping degree can influent morphology,electrical ability and gas sensitivity of PEDOT nanoparticles.The Bragg peaks of nanoparticles at 6.7°,12.7°,25° were observed by XRD and the better orientation of molecular chain was attributed to the effective doping of toluene-p-sulfonic acid,which also resulted in an enhancement of thermal stability of nanoparticles than conventional PEDOT.展开更多
The surface pressure-Area isotherms of Reversed Duckweed amphiphili polymer were examined in view of their chemical structure and two- dimentional properties of polymer monolayer were studied.
Single-phase homogeneous Ce1-x ZrxO2 solid versed microemulsion method. The structural properties solutions with various compositions were synthesized using the reand performance of Ce1- xZrxO2 were studied using XRD,...Single-phase homogeneous Ce1-x ZrxO2 solid versed microemulsion method. The structural properties solutions with various compositions were synthesized using the reand performance of Ce1- xZrxO2 were studied using XRD, BET, SEM, HRTEM, TPR and CO oxidation measurements. The results show that in the range of x = 0.4 - 0.5 and x = 0.6 - 1.0, the solid solutions posses the cubic and the tetragonal phase structure, respectively, Solids obtained by the reversed microemulsion method were more homogeneous on the whole range of composition, XRD investigations of the prepared materials did not show segregation of cerium or zirconium oxides, Highly uniform nanosize solid solution particles of ceria-zirconia with high specific area （146.7 m^2·g^-1） were attained under the conditions of this study. The TPR results and CO oxidation measurements indicate that the performance of the CeO2-ZrO2 mixed oxides is strongly related to the composition and structure of the oxides. Enhancement of the activity was found for the catalyst prepared by reversed microemulsion method as compared to the sample prepared by sol-gel method.展开更多
The antigenic variation of influenza A virus hemagglutinin (HA) glycoproteins requires frequent changes in vaccine formulation. The new strategy of creating influenza seed strains for vaccine production is to generate...The antigenic variation of influenza A virus hemagglutinin (HA) glycoproteins requires frequent changes in vaccine formulation. The new strategy of creating influenza seed strains for vaccine production is to generate 7 + 1 reassortants that contain seven genes from a high-yield virus A/Puerto Rico/8/34[A/PR/8/34](H1N1) and the HA gene from the circulating strains. By using this DNA-based cotransfection technique, we generated 7 + 1 reassortants rgH3N1 which had the antigenic determinants of influenza virus A/Songbird/HongKong/102/00[SB/HK/01](H3N8) and 7 other genes from A/PR/ 8/34. The hemagglutinin of A/Songbird/HongKong/102/00 is 96.3% homologous to that of A/Equine/Jilin/98[Eq/Jl/89] (H3N8). The resulting virus rgH3N1 grows to high HA titers in chicken embryonated eggs, allowing vaccine preparation in unconcentrated allantoic fluid. The rgH3N1 is stable after multiple passages in embryonated eggs. The reassortant rgH3N1 virus could be used as vaccine candidate to reduce the reemergence of equine influenza outbreaks.展开更多
The precursors of La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ(LSCCF, x=0.05, 0.10, 0.15, 0.20) as the cathode materials for intermediate temperature solid oxide fuel cell (ITSOFC) were prepared by reverse titration co-precipitatio...The precursors of La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ(LSCCF, x=0.05, 0.10, 0.15, 0.20) as the cathode materials for intermediate temperature solid oxide fuel cell (ITSOFC) were prepared by reverse titration co-precipitation method with metal-nitrates as starting materials and mixed alkali (NaOH and Na2CO3) as a precipitating agent. The formation process of LSCCF from the precursors was monitored by TG-DSC, and the crystal structure and particles morphology of the precursors which were calcined at 600, 800, 1000 ℃ for 3 h were characterized using XRD, SEM technologies. Compared with the solid state reaction of constituent oxides, when the pH value of the precipitating solution was in the range of 9.1～9.5, the LSCCF powders from the precursors caclined at 800 ℃ for 3 h had high purity, homogeneous and single perovskite phase. The electrical conductivity of the LSCCF samples sintered at 1200 ℃ for 3 h, which was measured as a function of temperatures from 100 to 800 ℃ by DC four-probe method in air, decreased with x from 0.05 to 0.20. The value of electrical conductivity was almost equal because of Ca2+, Sr2+ co-dopant resulting in the 'mix effect' while x=0.10 or 0.15. The electrical conductivity of all doped samples was higher than 100 S·cm-1 at intermediate temperatures from 500 to 800 ℃, and there was good compatibility between the LSCCF cathode and Ce0.8Sm0.2O2 electrolyte.展开更多
Magnetic properties and magnetization processes of Co nanowire arrays with various packing densities are investigated by means of object-oriented micromagnetic framework（OOMMF） software package with finite differenc...Magnetic properties and magnetization processes of Co nanowire arrays with various packing densities are investigated by means of object-oriented micromagnetic framework（OOMMF） software package with finite difference micromagnetic simulations. The packing density of nanowires is changed with the diameter, number of nanowires and center-to-center spacing between the wires. The magnetization reversal mechanism and squareness of the hysteresis loops of the nanowire arrays are very sensitive to the packing density of nanowires. Clear steps and plateaux on the demagnetization are visible,which turns out that dipolar interactions among the wires have a significant influence on switching field.展开更多
Two novel compounds {[Cu（IBG）（4,4-bipy）（H2O）2]2·11H2O}n（1） and {[Co（IBG）-（μ-H2O）（H2O）2]·2H2O}n（2） based on isophthaloylbisglycine（H2IBG） have been synthesized and structurally characterize...Two novel compounds {[Cu（IBG）（4,4-bipy）（H2O）2]2·11H2O}n（1） and {[Co（IBG）-（μ-H2O）（H2O）2]·2H2O}n（2） based on isophthaloylbisglycine（H2IBG） have been synthesized and structurally characterized by thermogravimetric analysis, elemental analysis and single-crystal X-ray diffraction. Compound 1 shows a 1D chain sine/cosine chain structure, and compound 2 can be characterized as a 4-connected sql tetragonal planar network with the point symbol of {44·62}. Compound 2 has been characterized by magnetic measurements. In addition, 1 and 2 display an interesting reversible crystal-to-amorphous transformation.展开更多
基金supported by National Natural Science Foundation of China Grant No. 52067008China Jiangxi Provincial Planning Project Grant No. 20181BAB206035Qingjiang Excellent Young Talents Program,Jiangxi University of Science and Technology (JXUST)。
文摘In this article, a new variable leakage flux reverse salient-pole motor(VLF-RSPM) is raised to widen the speed range. The innovation is to realize both reverse salient-pole characteristics and variable leakage flux characteristics by using a method of adding magnetic bridges and magnetic barriers. Firstly, the evolution of the topological structure and working principle of the motor are introduced. Secondly, based on 2D Finite Element Analysis(FEA), the electromagnetic properties and noise of the motor are analyzed in detail, and the electromagnetic properties are contrasted with that of the conventional V-type synchronous motor(CVTSM). The results show that VLF-RSPM has the advantages of small torque ripple, strong magnetic weakening ability, low noise, high efficiency, and low risk of permanent magnet demagnetization under different conditions. In addition, it is verified that the proposed motor extends the speed range.
基金supported by the Inner Mongolia Autonomous Region Science and Technology Major Special Project(Grant No.2021SZD0082).
文摘Stainless steels are used in a wide range of complex environments due to their excellent corrosion resistance.Multiphase stainless steels can offer an excellent combination of strength,toughness and corrosion resistance due to the coexistence of different microstructures.The microstructure and mechanical properties of a novel cast multiphase stainless steel,composed of martensite,ferrite,and austenite,were investigated following appropriate heat treatment processes:solution treatment at 1,050℃ for 0.5 h followed by water quenching to room temperature,and aging treatment at 500℃ for 4 h followed by water quenching to room temperature.Results show reversed austenite is formed by diffusion of Ni element during aging process,and the enrichment of Ni atoms directly determines the mechanical stability of austenite.The austenite with a lower Ni content undergoes a martensitic transformation during plastic deformation.The tensile strength of the specimen exceeds 1,100 MPa and the elongation exceeds 24%after solid solution,and further increases to 1,247 MPa and 25%after aging treatment.This enhancement is due to the TRIP effect of austenite and the precipitation of the nanoscale G-phase pinning dislocations in ferrite and martensite.
文摘Ni/n-SiO2 composite coating was electrodeposited by brush-plating with pulse-reverse current（RC）. The morphology, hardness, and tribological properties of the coating were investigated and compared with those of Ni and composite coatings electrodeposited with direct current（DC）. The results indicate that Ni/n-SiO2 composite coating electrodeposited by RC, because of RC and the nano powders, has denser coating, finer crystal grains, higher hardness（HV650.0, nearly 1.5 times higher than that of Ni coating electrodeposited by DC） and lower friction coefficient（nearly 0.62）, as a result, in the wearing experiment, the Ni/n-SiO2 composite coating electrodeposited by RC has the least worn loss. So this kind of coating has better wear resistance. And RC electro brush-plating can be used as a new technology of brush-plating in the area of wear resistance.
基金Funded by the National Natural Science Foundation of China (No. 60372002)
文摘Based on the study of a new type of conducting polymer poly （3,4-ethylenedioxythiophene） （PEDOT）,we focussed on the preparation and characteristics of PEDOT nanoparticles made by reversed micelle method.Moreover,we deeply investigated the optical,electrical and the thermal stability of PEDOT nanoparticles.The main results are as follows： the small-sized PEDOT nanoparticles were prepared and utilized by different methods,such as ultraviolet/visible （UV-Vis） spectroscopy,Fourier-transform infrared （FT- IR） spectrum,scanning electron microscopy（SEM） and so on.The results show that the amount of oxidizer,ultrasonic treatment,polymerizing temperature and doping degree can influent morphology,electrical ability and gas sensitivity of PEDOT nanoparticles.The Bragg peaks of nanoparticles at 6.7°,12.7°,25° were observed by XRD and the better orientation of molecular chain was attributed to the effective doping of toluene-p-sulfonic acid,which also resulted in an enhancement of thermal stability of nanoparticles than conventional PEDOT.
文摘The surface pressure-Area isotherms of Reversed Duckweed amphiphili polymer were examined in view of their chemical structure and two- dimentional properties of polymer monolayer were studied.
文摘Single-phase homogeneous Ce1-x ZrxO2 solid versed microemulsion method. The structural properties solutions with various compositions were synthesized using the reand performance of Ce1- xZrxO2 were studied using XRD, BET, SEM, HRTEM, TPR and CO oxidation measurements. The results show that in the range of x = 0.4 - 0.5 and x = 0.6 - 1.0, the solid solutions posses the cubic and the tetragonal phase structure, respectively, Solids obtained by the reversed microemulsion method were more homogeneous on the whole range of composition, XRD investigations of the prepared materials did not show segregation of cerium or zirconium oxides, Highly uniform nanosize solid solution particles of ceria-zirconia with high specific area （146.7 m^2·g^-1） were attained under the conditions of this study. The TPR results and CO oxidation measurements indicate that the performance of the CeO2-ZrO2 mixed oxides is strongly related to the composition and structure of the oxides. Enhancement of the activity was found for the catalyst prepared by reversed microemulsion method as compared to the sample prepared by sol-gel method.
文摘The antigenic variation of influenza A virus hemagglutinin (HA) glycoproteins requires frequent changes in vaccine formulation. The new strategy of creating influenza seed strains for vaccine production is to generate 7 + 1 reassortants that contain seven genes from a high-yield virus A/Puerto Rico/8/34[A/PR/8/34](H1N1) and the HA gene from the circulating strains. By using this DNA-based cotransfection technique, we generated 7 + 1 reassortants rgH3N1 which had the antigenic determinants of influenza virus A/Songbird/HongKong/102/00[SB/HK/01](H3N8) and 7 other genes from A/PR/ 8/34. The hemagglutinin of A/Songbird/HongKong/102/00 is 96.3% homologous to that of A/Equine/Jilin/98[Eq/Jl/89] (H3N8). The resulting virus rgH3N1 grows to high HA titers in chicken embryonated eggs, allowing vaccine preparation in unconcentrated allantoic fluid. The rgH3N1 is stable after multiple passages in embryonated eggs. The reassortant rgH3N1 virus could be used as vaccine candidate to reduce the reemergence of equine influenza outbreaks.
基金the National High-Tech Development Plan (2006AA05Z417)the Natural Science Foundation of Lia-oning Province (20062145)the Education department of Liaoning Province (05L073)
文摘The precursors of La0.7Sr0.3-xCaxCo0.9Fe0.1O3-δ(LSCCF, x=0.05, 0.10, 0.15, 0.20) as the cathode materials for intermediate temperature solid oxide fuel cell (ITSOFC) were prepared by reverse titration co-precipitation method with metal-nitrates as starting materials and mixed alkali (NaOH and Na2CO3) as a precipitating agent. The formation process of LSCCF from the precursors was monitored by TG-DSC, and the crystal structure and particles morphology of the precursors which were calcined at 600, 800, 1000 ℃ for 3 h were characterized using XRD, SEM technologies. Compared with the solid state reaction of constituent oxides, when the pH value of the precipitating solution was in the range of 9.1～9.5, the LSCCF powders from the precursors caclined at 800 ℃ for 3 h had high purity, homogeneous and single perovskite phase. The electrical conductivity of the LSCCF samples sintered at 1200 ℃ for 3 h, which was measured as a function of temperatures from 100 to 800 ℃ by DC four-probe method in air, decreased with x from 0.05 to 0.20. The value of electrical conductivity was almost equal because of Ca2+, Sr2+ co-dopant resulting in the 'mix effect' while x=0.10 or 0.15. The electrical conductivity of all doped samples was higher than 100 S·cm-1 at intermediate temperatures from 500 to 800 ℃, and there was good compatibility between the LSCCF cathode and Ce0.8Sm0.2O2 electrolyte.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.51401001,51371002,and 51331003)the International S&T Cooperation Program of China(Grant No.2015DFG52020)
文摘Magnetic properties and magnetization processes of Co nanowire arrays with various packing densities are investigated by means of object-oriented micromagnetic framework（OOMMF） software package with finite difference micromagnetic simulations. The packing density of nanowires is changed with the diameter, number of nanowires and center-to-center spacing between the wires. The magnetization reversal mechanism and squareness of the hysteresis loops of the nanowire arrays are very sensitive to the packing density of nanowires. Clear steps and plateaux on the demagnetization are visible,which turns out that dipolar interactions among the wires have a significant influence on switching field.
基金supported by the National Natural Science Foundation of China(No.2137109291022011)+1 种基金National Basic Research Program of China(2010CB923303)the Universities Natural Science Research Project of Anhui Province(No.KJHS2017B05)
文摘Two novel compounds {[Cu（IBG）（4,4-bipy）（H2O）2]2·11H2O}n（1） and {[Co（IBG）-（μ-H2O）（H2O）2]·2H2O}n（2） based on isophthaloylbisglycine（H2IBG） have been synthesized and structurally characterized by thermogravimetric analysis, elemental analysis and single-crystal X-ray diffraction. Compound 1 shows a 1D chain sine/cosine chain structure, and compound 2 can be characterized as a 4-connected sql tetragonal planar network with the point symbol of {44·62}. Compound 2 has been characterized by magnetic measurements. In addition, 1 and 2 display an interesting reversible crystal-to-amorphous transformation.
