The oil pan used in car engine is one of the important structureparts in the car, which is, in general, deep drawn and difficult toform. The deep-drawing processes of the oil pan used in the enginefor 'Small Flag&...The oil pan used in car engine is one of the important structureparts in the car, which is, in general, deep drawn and difficult toform. The deep-drawing processes of the oil pan used in the enginefor 'Small Flag' Car of the First Automobile Manufactory is analyzedby using the integrative CAD/CAE/CAM technique of stamping die,including the CAD software CATIA and the sheet-metal stamping CAEsoftware KMAS developed independently.展开更多
为探究进气口宽度对火旋风燃烧特性的影响,利用自然驱动的四面边墙夹缝式装置对不同进气口宽度使用150,200,250 mm 3种直径进行实验研究。由燃料质量随时间变化曲线得出准稳态阶段火旋风的质量燃烧速率;利用摄像机记录火焰的连续图像并...为探究进气口宽度对火旋风燃烧特性的影响,利用自然驱动的四面边墙夹缝式装置对不同进气口宽度使用150,200,250 mm 3种直径进行实验研究。由燃料质量随时间变化曲线得出准稳态阶段火旋风的质量燃烧速率;利用摄像机记录火焰的连续图像并获得火焰高度。结果表明:针对实验室小型火旋风(150~250 mm),在进气口宽度为35 mm左右时,火旋风的燃烧速率最大,即火旋风的燃烧强度存在1个最佳的进气口宽度;当火焰高度达到最高时,环量也存在1个临界值。展开更多
The effect of etching environment(opened or closed)on the synthesis and electrochemical properties of V_(2)C MXene was studied.V_(2)C MXene samples were synthesized by selectively etching of V2AlC at 90℃in two differ...The effect of etching environment(opened or closed)on the synthesis and electrochemical properties of V_(2)C MXene was studied.V_(2)C MXene samples were synthesized by selectively etching of V2AlC at 90℃in two different environments:opened environment(OE)in oil bath pans under atmosphere pressure and closed environment(CE)in hydrothermal reaction kettles under higher pressures.In OE,only NaF(sodium fluoride)+HCl(hydrochloric acid)etching solution can be used to synthesize highly pure V_(2)C MXene.However,in CE,both LiF(lithium fluoride)+HCl and NaF+HCl etchant can be used to prepare V_(2)C MXene.Moreover,the V_(2)C MXene samples made in CE had higher purity and better-layered structure than those made in OE.Although the purity of V_(2)C obtained by LiF+HCl is lower than that of V_(2)C obtained using NaF+HCl,it shows better electrochemical performance as anodes of lithium-ion batteries(LIBs).Therefore,etching in CE is a better method for preparing highly pure V_(2)C MXene,which provides a reference for expanding the synthesis methods of V_(2)C with better electrochemical properties.展开更多
基金the National Natural Science Foundation of China (No.19832020)the Key Proiect of Ministry of Education of China
文摘The oil pan used in car engine is one of the important structureparts in the car, which is, in general, deep drawn and difficult toform. The deep-drawing processes of the oil pan used in the enginefor 'Small Flag' Car of the First Automobile Manufactory is analyzedby using the integrative CAD/CAE/CAM technique of stamping die,including the CAD software CATIA and the sheet-metal stamping CAEsoftware KMAS developed independently.
文摘为探究进气口宽度对火旋风燃烧特性的影响,利用自然驱动的四面边墙夹缝式装置对不同进气口宽度使用150,200,250 mm 3种直径进行实验研究。由燃料质量随时间变化曲线得出准稳态阶段火旋风的质量燃烧速率;利用摄像机记录火焰的连续图像并获得火焰高度。结果表明:针对实验室小型火旋风(150~250 mm),在进气口宽度为35 mm左右时,火旋风的燃烧速率最大,即火旋风的燃烧强度存在1个最佳的进气口宽度;当火焰高度达到最高时,环量也存在1个临界值。
基金supported by the National Natural Science Foundation of China(51772077)the Program for Innovative Research Team(in Science and Technology)in University of Henan Province(19IRTSTHN027)+5 种基金the Fundamental Research Funds for the Universities of Henan Province(NSFRF200101)the China Postdoctoral Science Foundation(2019M652537)the Henan Postdoctoral Foundation(19030065)the Henan Province Key Science and Tech-nology Research Projects(202102310628)the Foundation of Henan Educational Committee(20B430006)the Doctoral Foundation of Henan Polytechnic University(B2019-41).
文摘The effect of etching environment(opened or closed)on the synthesis and electrochemical properties of V_(2)C MXene was studied.V_(2)C MXene samples were synthesized by selectively etching of V2AlC at 90℃in two different environments:opened environment(OE)in oil bath pans under atmosphere pressure and closed environment(CE)in hydrothermal reaction kettles under higher pressures.In OE,only NaF(sodium fluoride)+HCl(hydrochloric acid)etching solution can be used to synthesize highly pure V_(2)C MXene.However,in CE,both LiF(lithium fluoride)+HCl and NaF+HCl etchant can be used to prepare V_(2)C MXene.Moreover,the V_(2)C MXene samples made in CE had higher purity and better-layered structure than those made in OE.Although the purity of V_(2)C obtained by LiF+HCl is lower than that of V_(2)C obtained using NaF+HCl,it shows better electrochemical performance as anodes of lithium-ion batteries(LIBs).Therefore,etching in CE is a better method for preparing highly pure V_(2)C MXene,which provides a reference for expanding the synthesis methods of V_(2)C with better electrochemical properties.
