Cored wires for electric arc spraying of Al/Al 2 O 3 MMC coatings were developed, with Al 2 O 3 powder as the core material and commercial aluminium strip as the retaining sheath. The bond strength, ...Cored wires for electric arc spraying of Al/Al 2 O 3 MMC coatings were developed, with Al 2 O 3 powder as the core material and commercial aluminium strip as the retaining sheath. The bond strength, Al 2 O 3 content, microstructure, micro-hardness and wear resistance of coatings produced by arc spraying of the cored wires were experimentally investigated and were compared with those of pure aluminum coating.展开更多
Salt lake brine is a complex salt-water system under natural environment.Although many models can express the thermodynamic properties and phase equilibrium of electrolyte aqueous solution,the multi-temperature charac...Salt lake brine is a complex salt-water system under natural environment.Although many models can express the thermodynamic properties and phase equilibrium of electrolyte aqueous solution,the multi-temperature characteristics and predictability are still the goals of model development.In this study,a comprehensive thermodynamic model system is re-established based on the eNRTL model and some improvements:(1) new expression of long-range electrostatic term with symmetrical reference state is proposed to handle the electrolyte solution covering entire concentration range;(2) the temperature dependence of the binary interaction parameters is formulated with a Gibbs Helmholtz expression containing three temperature coefficients,the liquid parameters,which associated with Gibbs energy,enthalpy,and heat capacity contribution;and(3) liquid parameters and solid species data are regressed from properties and solubility data at full temperature range.Together the activity coefficient model,property models and parameters of liquid and solid offer a comprehensive thermodynamic model system for the typical bittern of MgCl2-CaCl2-H2 O binary and ternary systems,and it shows excellent agreement with the literature data for the ternary and binary systems.The successful prediction of complete phase diagram of ternary system shows that the model has the ability to deal with high concentration and high non-idealitv system,and the ability to extrapolate the temperature.展开更多
The potential—pH diagrams of the Cr-H2O system at temperatures of 298, 323, 373 and 423 K were established through thermodynamic calculation with coupling of experimental results. The potential—pH diagram at 298 K a...The potential—pH diagrams of the Cr-H2O system at temperatures of 298, 323, 373 and 423 K were established through thermodynamic calculation with coupling of experimental results. The potential—pH diagram at 298 K agrees well with the previously reported results. Based on the potential—pH diagrams of the Cr-H2O and Fe-H2O systems, IR spectra and XRD pattern, the existence forms of iron in the potassium chromate were analyzed, and the methods of iron removal were investigated. The results show that the existence forms of iron in the potassium chromate are potassium ferrate. These results are instructive and helpful to the hydrometallurgical processing of chromite ore.展开更多
1 Introduction The brines with high concentrations of magnesium and boron resources are widely distributed in the Qaidam Basin of the Qinghai-Tibet plateau,China(Zheng&Tang,1988).Although some works on the ternary...1 Introduction The brines with high concentrations of magnesium and boron resources are widely distributed in the Qaidam Basin of the Qinghai-Tibet plateau,China(Zheng&Tang,1988).Although some works on the ternary system展开更多
One-dimensional(1D, wire-and fiber-shaped)supercapacitors have recently attracted interest due to their roll-up, micrometer size and potential applications in portable or wearable electronics. Herein, a 1D wireshaped ...One-dimensional(1D, wire-and fiber-shaped)supercapacitors have recently attracted interest due to their roll-up, micrometer size and potential applications in portable or wearable electronics. Herein, a 1D wireshaped electrode was developed based on Fe_3O_4 nanosheet arrays connected on the Fe wire, which was prepared via oxidation of Fe wire in 0.1 M KCl solution(pH 3) with O2-rich environment under 70 °C. The obtained Fe_3O_4 nanosheet arrays displayed a high specific capacitance(20.8 m F cm^(-1) at 10 mV s^(-1)) and long cycling lifespan(91.7% retention after 2500 cycles). Theexcellent performance may attribute to the connected nanosheet structure with abundant open spaces and the intimate contact between the Fe_3O_4 and iron substrate. In addition, a wire-shaped asymmetric supercapacitor was fabricated and had excellent capacitive properties with a high energy density(9 l Wh cm^(-2)) at power density of 532.7 l W cm^(-2) and remarkable long-term cycling performance(99% capacitance retention after 2000 cycles).Considering low cost and earth-abundant electrode material, as well as outstanding electrochemical properties, the assembled supercapacitor will possess enormous potential for practical applications in portable electronic device.展开更多
Since Bi2Sr2Ca1Cu2O8＋x（Bi2212） wires are subject to mechanical loadings, degradation of critical current will occur. The effect of compressive loadings on the critical current of Bi2212 wire is studied by consideri...Since Bi2Sr2Ca1Cu2O8＋x（Bi2212） wires are subject to mechanical loadings, degradation of critical current will occur. The effect of compressive loadings on the critical current of Bi2212 wire is studied by considering micro-buckling of filament. A Bi2212 wire is regarded as a unidirectional filament-reinforced composite in the theoretical analysis. By considering the influence of inclusion, the micro-buckling wavelength can be derived by using a two-dimensional model. Based on the experimental results, the critical current is fitted as a function of buckling wavelength. It is found that the decrease of the critical current is directly proportional to the reciprocal of square of the buckling wavelength. Change of micro-buckling wavelength with material parameters is discussed. A critical strain in the wire with a filament bridge is analyzed using the finite element method.展开更多
The isothermal phase diagram of the Cu2O-Al2O3-SiO2 ternary system at 1150℃ was reported for the samples which were prepared from sol-gel method and quenched by water after being heated at 1150℃ for 12 h. Based on t...The isothermal phase diagram of the Cu2O-Al2O3-SiO2 ternary system at 1150℃ was reported for the samples which were prepared from sol-gel method and quenched by water after being heated at 1150℃ for 12 h. Based on the conventional X-ray powder diffraction （XRD） and in situ high-temperature XRD quantitative analysis,in addition to scanning electron microscopy measurement,the phase identification was achieved. Combining the deduction from the component phase diagrams of the binary systems using the phase equilibrium theorem,the primary isothermal phase diagram was plotted over the composition area Cu2O-mullite-SiO2. In this area,the approximate composition areas of two two-phase regions and one three-phase region,（L2＋Cr）,（L2＋M）,and （L1＋L2＋Tr）,were determined. Moreover,the precise composition areas of both of the three-phase regions （L2＋Cr＋M） and （L2＋M＋A） were determined according to the results of conventional and in situ high-temperature XRD quantitative analysis by Rietveld method.展开更多
Ceria-yttria co-doped zirconia-based multi-components ceramics, with superfine alumina dispersed in the matrix, possess excellent fracture toughness, strength and thermal stability. However, the mechanical properties ...Ceria-yttria co-doped zirconia-based multi-components ceramics, with superfine alumina dispersed in the matrix, possess excellent fracture toughness, strength and thermal stability. However, the mechanical properties and microstructure are strongly dependent on the composition and the fabrication procedure, especially the composition of zirconia containing multi-component ceramics.展开更多
A new viewpoint of computer program poubaix diagram was proposed on traditional φ pH diagrams. All equilibrium principle and activity term method were used to plot φ pH diagrams for M H 2O systems based on the therm...A new viewpoint of computer program poubaix diagram was proposed on traditional φ pH diagrams. All equilibrium principle and activity term method were used to plot φ pH diagrams for M H 2O systems based on the thermochemical database developed. And a new method——arithmetic geometric method is used to solve nonlinear equations group. The calculation procedure is proved to be efficient and convergent. The method seldom depends on artificial intervention and can extend to multi component all equilibrium φ pH diagrams such as M ligand H 2O system. [展开更多
The mathematical topological rule was applied to plot the predominance area diagram.Based on the analysis of the mutually conjugated,only two diagrams were the best topological embryonic graphs to build the predominan...The mathematical topological rule was applied to plot the predominance area diagram.Based on the analysis of the mutually conjugated,only two diagrams were the best topological embryonic graphs to build the predominance area diagram of Me-S-O system.Combined with topological rules and thermodynamic calculation,four relation-diagrams were denoted asαandβstable and unstable plane-topological diagrams,which were plotted for the Pb-S-O system and Zn-S-O system.The results show thatβstable plane-topological diagram of Pb-S-O system andαstable one of Zn-S-O system are in accordance with the traditional predominance area diagram,which indicates that it is feasible to plot the predominance area diagram based on mathematical topological rules.Meanwhile,αunstable plane-topological diagram of Pb-S-O system can elucidate the phenomenon that metallic lead exists in higher oxygen and sulfur pressure area in modern bath smelting furnace.The mathematical topological rules broaden the application scope of the predominance area diagram and enrich the practice of its plotting.展开更多
CaSO4 Nanorods/wires were synthesized in quaternary W/O microemulsion soluti on containing triton X-100, cyclohexane and n-pentanol. Transmission electro n microscopy (TEM) was utilized to characterize the shape and s...CaSO4 Nanorods/wires were synthesized in quaternary W/O microemulsion soluti on containing triton X-100, cyclohexane and n-pentanol. Transmission electro n microscopy (TEM) was utilized to characterize the shape and size of products a s-prepared, as well as electron diffraction (ED) pattern was obtained for desi gnated nanorods (wires). It is revealed that ù0 (molar ratio of water to surfa ctant),reactants concentration and aging time play an important role in the form ation of different morphologies and size of synthesized CaSO4 nanocrystal.展开更多
文摘Cored wires for electric arc spraying of Al/Al 2 O 3 MMC coatings were developed, with Al 2 O 3 powder as the core material and commercial aluminium strip as the retaining sheath. The bond strength, Al 2 O 3 content, microstructure, micro-hardness and wear resistance of coatings produced by arc spraying of the cored wires were experimentally investigated and were compared with those of pure aluminum coating.
基金financial support of the National Natural Science Foundation of China(U1407204,U1707602)the Yangtze Scholars and Innovative Research Team in University of Education of China+1 种基金the Innovative Research Team of Tianjin Municipal Education Commission(TD12-5004)Foundation of Tianjin Key Laboratory of Marine Resources and Chemistry(201602)。
文摘Salt lake brine is a complex salt-water system under natural environment.Although many models can express the thermodynamic properties and phase equilibrium of electrolyte aqueous solution,the multi-temperature characteristics and predictability are still the goals of model development.In this study,a comprehensive thermodynamic model system is re-established based on the eNRTL model and some improvements:(1) new expression of long-range electrostatic term with symmetrical reference state is proposed to handle the electrolyte solution covering entire concentration range;(2) the temperature dependence of the binary interaction parameters is formulated with a Gibbs Helmholtz expression containing three temperature coefficients,the liquid parameters,which associated with Gibbs energy,enthalpy,and heat capacity contribution;and(3) liquid parameters and solid species data are regressed from properties and solubility data at full temperature range.Together the activity coefficient model,property models and parameters of liquid and solid offer a comprehensive thermodynamic model system for the typical bittern of MgCl2-CaCl2-H2 O binary and ternary systems,and it shows excellent agreement with the literature data for the ternary and binary systems.The successful prediction of complete phase diagram of ternary system shows that the model has the ability to deal with high concentration and high non-idealitv system,and the ability to extrapolate the temperature.
基金Project(2007CB613501) supported by the National Basic Research Program of ChinaProject(2006BAC02A05) supported by the National Science and Technology Pillar Program of ChinaProject(50904058) supported by the National Natural Science Foundation of China
文摘The potential—pH diagrams of the Cr-H2O system at temperatures of 298, 323, 373 and 423 K were established through thermodynamic calculation with coupling of experimental results. The potential—pH diagram at 298 K agrees well with the previously reported results. Based on the potential—pH diagrams of the Cr-H2O and Fe-H2O systems, IR spectra and XRD pattern, the existence forms of iron in the potassium chromate were analyzed, and the methods of iron removal were investigated. The results show that the existence forms of iron in the potassium chromate are potassium ferrate. These results are instructive and helpful to the hydrometallurgical processing of chromite ore.
基金Financial supports from the National Natural Science Foundation of China (21276194 and 21306136)Key Laboratory of Salt Lake Resources and Chemistry at Chinese Academy Sciences (KLSLRC-KF-13-HX-2)Tianjin Key Laboratory of Marine Resources and Chemistry (201206)
文摘1 Introduction The brines with high concentrations of magnesium and boron resources are widely distributed in the Qaidam Basin of the Qinghai-Tibet plateau,China(Zheng&Tang,1988).Although some works on the ternary system
基金supported by Zhujiang New Stars of Science and Technology (2014J2200061)
文摘One-dimensional(1D, wire-and fiber-shaped)supercapacitors have recently attracted interest due to their roll-up, micrometer size and potential applications in portable or wearable electronics. Herein, a 1D wireshaped electrode was developed based on Fe_3O_4 nanosheet arrays connected on the Fe wire, which was prepared via oxidation of Fe wire in 0.1 M KCl solution(pH 3) with O2-rich environment under 70 °C. The obtained Fe_3O_4 nanosheet arrays displayed a high specific capacitance(20.8 m F cm^(-1) at 10 mV s^(-1)) and long cycling lifespan(91.7% retention after 2500 cycles). Theexcellent performance may attribute to the connected nanosheet structure with abundant open spaces and the intimate contact between the Fe_3O_4 and iron substrate. In addition, a wire-shaped asymmetric supercapacitor was fabricated and had excellent capacitive properties with a high energy density(9 l Wh cm^(-2)) at power density of 532.7 l W cm^(-2) and remarkable long-term cycling performance(99% capacitance retention after 2000 cycles).Considering low cost and earth-abundant electrode material, as well as outstanding electrochemical properties, the assembled supercapacitor will possess enormous potential for practical applications in portable electronic device.
基金Project supported by the National Natural Science Foundation of China(Nos.11327802,11472120,and 11421062)the National Key Project of Magneto-Constrained Fusion Energy Development Program(No.2013GB110002)the Fundamental Research Funds for the Central Universities(No.lzujbky-2017-k18)
文摘Since Bi2Sr2Ca1Cu2O8＋x（Bi2212） wires are subject to mechanical loadings, degradation of critical current will occur. The effect of compressive loadings on the critical current of Bi2212 wire is studied by considering micro-buckling of filament. A Bi2212 wire is regarded as a unidirectional filament-reinforced composite in the theoretical analysis. By considering the influence of inclusion, the micro-buckling wavelength can be derived by using a two-dimensional model. Based on the experimental results, the critical current is fitted as a function of buckling wavelength. It is found that the decrease of the critical current is directly proportional to the reciprocal of square of the buckling wavelength. Change of micro-buckling wavelength with material parameters is discussed. A critical strain in the wire with a filament bridge is analyzed using the finite element method.
基金the National Natural Science Foundation of China (No. 20471010)the Scien-tific Research Fund of Hunan Provincial Education Department (No. 05c173).
文摘The isothermal phase diagram of the Cu2O-Al2O3-SiO2 ternary system at 1150℃ was reported for the samples which were prepared from sol-gel method and quenched by water after being heated at 1150℃ for 12 h. Based on the conventional X-ray powder diffraction （XRD） and in situ high-temperature XRD quantitative analysis,in addition to scanning electron microscopy measurement,the phase identification was achieved. Combining the deduction from the component phase diagrams of the binary systems using the phase equilibrium theorem,the primary isothermal phase diagram was plotted over the composition area Cu2O-mullite-SiO2. In this area,the approximate composition areas of two two-phase regions and one three-phase region,（L2＋Cr）,（L2＋M）,and （L1＋L2＋Tr）,were determined. Moreover,the precise composition areas of both of the three-phase regions （L2＋Cr＋M） and （L2＋M＋A） were determined according to the results of conventional and in situ high-temperature XRD quantitative analysis by Rietveld method.
文摘Ceria-yttria co-doped zirconia-based multi-components ceramics, with superfine alumina dispersed in the matrix, possess excellent fracture toughness, strength and thermal stability. However, the mechanical properties and microstructure are strongly dependent on the composition and the fabrication procedure, especially the composition of zirconia containing multi-component ceramics.
文摘A new viewpoint of computer program poubaix diagram was proposed on traditional φ pH diagrams. All equilibrium principle and activity term method were used to plot φ pH diagrams for M H 2O systems based on the thermochemical database developed. And a new method——arithmetic geometric method is used to solve nonlinear equations group. The calculation procedure is proved to be efficient and convergent. The method seldom depends on artificial intervention and can extend to multi component all equilibrium φ pH diagrams such as M ligand H 2O system. [
基金Project(2011AA061003) supported by the High-Tech Research and Development Program of China
文摘The mathematical topological rule was applied to plot the predominance area diagram.Based on the analysis of the mutually conjugated,only two diagrams were the best topological embryonic graphs to build the predominance area diagram of Me-S-O system.Combined with topological rules and thermodynamic calculation,four relation-diagrams were denoted asαandβstable and unstable plane-topological diagrams,which were plotted for the Pb-S-O system and Zn-S-O system.The results show thatβstable plane-topological diagram of Pb-S-O system andαstable one of Zn-S-O system are in accordance with the traditional predominance area diagram,which indicates that it is feasible to plot the predominance area diagram based on mathematical topological rules.Meanwhile,αunstable plane-topological diagram of Pb-S-O system can elucidate the phenomenon that metallic lead exists in higher oxygen and sulfur pressure area in modern bath smelting furnace.The mathematical topological rules broaden the application scope of the predominance area diagram and enrich the practice of its plotting.
文摘CaSO4 Nanorods/wires were synthesized in quaternary W/O microemulsion soluti on containing triton X-100, cyclohexane and n-pentanol. Transmission electro n microscopy (TEM) was utilized to characterize the shape and size of products a s-prepared, as well as electron diffraction (ED) pattern was obtained for desi gnated nanorods (wires). It is revealed that ù0 (molar ratio of water to surfa ctant),reactants concentration and aging time play an important role in the form ation of different morphologies and size of synthesized CaSO4 nanocrystal.
