Mn_(3)Si_(2)Te_(6) is a ferrimagnetic nodal-line semiconductor with colossal angular magnetoresistance at ambient pressure.In this work,we investigated the effect of hydrostatic pressure on its electrical transport pr...Mn_(3)Si_(2)Te_(6) is a ferrimagnetic nodal-line semiconductor with colossal angular magnetoresistance at ambient pressure.In this work,we investigated the effect of hydrostatic pressure on its electrical transport properties,magnetic transition,and crystal structure by measuring resistivity,DC and AC magnetic susceptibility,and XRD under various pressures up to~20 GPa.Our results confirmed the occurrence of pressure-induced structural transition at P_(c)≈10–12 GPa accompanied by a concurrent drop of room-temperature resistance in Mn_(3)Si_(2)Te_(6).In the low-pressure phase at PP_(c),the sample exhibits a metallic behavior in the whole temperature range and its resistivity exhibits a kink anomaly at T_(M),characteristic of critical scattering around a magnetic transition.Recovery of the Raman spectrum upon decompression indicated that pressure-induced structural transition is reversible without amorphization under hydrostatic pressure conditions.Our present work not only resolves some existing controversial issues but also provides new insights into pressure-driven diverse behaviors of Mn_(3)Si_(2)Te_(6).展开更多
In this paper,flow of slightly rarefied compressible nitrogen in microchannels has been investigated numerically for low values of Reynolds and Mach numbers.The 2D governing equations were solved using Finite Element ...In this paper,flow of slightly rarefied compressible nitrogen in microchannels has been investigated numerically for low values of Reynolds and Mach numbers.The 2D governing equations were solved using Finite Element Method with first-order slip boundary conditions(Comsol Multiphysics software).A validation was performed by comparing with similar configuration from the literature.It was found that our model can accurately predict the pressure driven flow in microchannels.Several interesting findings are reported about the Relative pressure,longitudinal velocity,Mach number,effect of gas rarefaction and flow rate.展开更多
The ceramic membrane oxygen generation technology has advantages of high concentration of produced oxygen and potential nuclear and biochemical protection capability. The present paper studies the ceramic membrane tec...The ceramic membrane oxygen generation technology has advantages of high concentration of produced oxygen and potential nuclear and biochemical protection capability. The present paper studies the ceramic membrane technology for onboard oxygen generation. Comparisons are made to have knowledge of the effects of two kinds of ceramic membrane separation technologies on oxygen generation, namely electricity driven ceramic membrane separation oxygen generation technology (EDCMSOGT) and pressure driven ceramic membrane separation oxygen generation technology (PDCMSOGT). Experiments were conducted under different temperatures, pressures of feed air and produced oxygen flow rates. On the basis of these experiments, the flow rate of feed air, electric power provided, oxygen recovery rate and concentration of produced oxygen are compared under each working condition. It is concluded that the EDCMSOGT is the oxygen generation means more suitable for onboard conditions. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd.展开更多
Trajectory analysis of fuel injection into supersonic cross flow is studied in this paper. A directly-connected wind tunnel is constructed to provide stable supersonic freestream. Based on the test rig, the schlieren ...Trajectory analysis of fuel injection into supersonic cross flow is studied in this paper. A directly-connected wind tunnel is constructed to provide stable supersonic freestream. Based on the test rig, the schlieren system is established to reveal the fuel injection process visually. Subsequently, the method of quantitative schlieren is adopted to obtain data of both fuel/air interface and bow shock with the aid of Photoshop and Origin. Finally, the mechanism based on two influential factors of fuel injection angle and fuel injection driven pressure, is researched by vector analysis. A dimensionless model is deduced and analyzed. The curve fitting result is achieved. The relationship between the data and the two influential factors is established. The results provide not only the quantitative characteristics of the fuel injection in supersonic cross flow but also the valuable reference for the future computational simulation.展开更多
In this study,we present a calibration methodology for drinking water distribution network models using two hydraulic simulation approaches:Demand Driven Analysis(DDA)and Pressure Driven Analysis(PDA),implemented in E...In this study,we present a calibration methodology for drinking water distribution network models using two hydraulic simulation approaches:Demand Driven Analysis(DDA)and Pressure Driven Analysis(PDA),implemented in EPANET 2.2.The calibration process focuses on determining two critical parameters the discharge coefficient and the pressure exponent which govern flow behavior under pressure-dependent conditions.Unlike DDA,which assumes fixed consumption at nodes regardless of pressure,PDA accounts for variable flow rates based on available pressure,offering a more realistic representation of network performance during low-pressure scenarios.These coefficients were derived from national plumbing standards applicable to different consumer categories in Algeria and Romania,and integrated into the numerical models to enhance simulation accuracy.A detailed comparison between DDA and PDA is provided,highlighting the strengths and limitations of each approach.Importantly,this type of numerical model is especially valuable during the design phase of water distribution systems,when physical measurements are unavailable and planning decisions must rely on regulatory data and theoretical assumptions.展开更多
基金supported by the National Key R&D Program of China (Grant Nos. 2023YFA1406100, 2022YFA1403900, 2024YFA1408400, 2021YFA1400200, 2022YFA1403800, and 2023YFA1406500)the National Natural Science Foundation of China (Grant Nos. 12174424, 12025408, 11921004, U22A6005, and 12274459)+1 种基金the Youth Innovation Promotion Association of Chinese Academy of Sciences (Grant No. 2023007)the Chinese Academy of Sciences President’s International Fellowship Initiative (Grant No. 2024PG0003)。
文摘Mn_(3)Si_(2)Te_(6) is a ferrimagnetic nodal-line semiconductor with colossal angular magnetoresistance at ambient pressure.In this work,we investigated the effect of hydrostatic pressure on its electrical transport properties,magnetic transition,and crystal structure by measuring resistivity,DC and AC magnetic susceptibility,and XRD under various pressures up to~20 GPa.Our results confirmed the occurrence of pressure-induced structural transition at P_(c)≈10–12 GPa accompanied by a concurrent drop of room-temperature resistance in Mn_(3)Si_(2)Te_(6).In the low-pressure phase at PP_(c),the sample exhibits a metallic behavior in the whole temperature range and its resistivity exhibits a kink anomaly at T_(M),characteristic of critical scattering around a magnetic transition.Recovery of the Raman spectrum upon decompression indicated that pressure-induced structural transition is reversible without amorphization under hydrostatic pressure conditions.Our present work not only resolves some existing controversial issues but also provides new insights into pressure-driven diverse behaviors of Mn_(3)Si_(2)Te_(6).
文摘In this paper,flow of slightly rarefied compressible nitrogen in microchannels has been investigated numerically for low values of Reynolds and Mach numbers.The 2D governing equations were solved using Finite Element Method with first-order slip boundary conditions(Comsol Multiphysics software).A validation was performed by comparing with similar configuration from the literature.It was found that our model can accurately predict the pressure driven flow in microchannels.Several interesting findings are reported about the Relative pressure,longitudinal velocity,Mach number,effect of gas rarefaction and flow rate.
文摘The ceramic membrane oxygen generation technology has advantages of high concentration of produced oxygen and potential nuclear and biochemical protection capability. The present paper studies the ceramic membrane technology for onboard oxygen generation. Comparisons are made to have knowledge of the effects of two kinds of ceramic membrane separation technologies on oxygen generation, namely electricity driven ceramic membrane separation oxygen generation technology (EDCMSOGT) and pressure driven ceramic membrane separation oxygen generation technology (PDCMSOGT). Experiments were conducted under different temperatures, pressures of feed air and produced oxygen flow rates. On the basis of these experiments, the flow rate of feed air, electric power provided, oxygen recovery rate and concentration of produced oxygen are compared under each working condition. It is concluded that the EDCMSOGT is the oxygen generation means more suitable for onboard conditions. (C) 2016 Chinese Society of Aeronautics and Astronautics. Production and hosting by Elsevier Ltd.
文摘Trajectory analysis of fuel injection into supersonic cross flow is studied in this paper. A directly-connected wind tunnel is constructed to provide stable supersonic freestream. Based on the test rig, the schlieren system is established to reveal the fuel injection process visually. Subsequently, the method of quantitative schlieren is adopted to obtain data of both fuel/air interface and bow shock with the aid of Photoshop and Origin. Finally, the mechanism based on two influential factors of fuel injection angle and fuel injection driven pressure, is researched by vector analysis. A dimensionless model is deduced and analyzed. The curve fitting result is achieved. The relationship between the data and the two influential factors is established. The results provide not only the quantitative characteristics of the fuel injection in supersonic cross flow but also the valuable reference for the future computational simulation.
文摘In this study,we present a calibration methodology for drinking water distribution network models using two hydraulic simulation approaches:Demand Driven Analysis(DDA)and Pressure Driven Analysis(PDA),implemented in EPANET 2.2.The calibration process focuses on determining two critical parameters the discharge coefficient and the pressure exponent which govern flow behavior under pressure-dependent conditions.Unlike DDA,which assumes fixed consumption at nodes regardless of pressure,PDA accounts for variable flow rates based on available pressure,offering a more realistic representation of network performance during low-pressure scenarios.These coefficients were derived from national plumbing standards applicable to different consumer categories in Algeria and Romania,and integrated into the numerical models to enhance simulation accuracy.A detailed comparison between DDA and PDA is provided,highlighting the strengths and limitations of each approach.Importantly,this type of numerical model is especially valuable during the design phase of water distribution systems,when physical measurements are unavailable and planning decisions must rely on regulatory data and theoretical assumptions.
