The umbilical cable is a vital component of subsea production systems that provide power,chemical agents,control signals et al.,and its requirement for reliability is exceedingly high.However,as the umbilical cable is...The umbilical cable is a vital component of subsea production systems that provide power,chemical agents,control signals et al.,and its requirement for reliability is exceedingly high.However,as the umbilical cable is a composite structure comprising multiple functional units,the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency.In this paper,the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed.The global dynamic analytical model is first established to determine the maximum tension load,then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM).Based on the mechanical analytical model,the reliability of umbilical cable under tension load is studied using response surface method(RSM)and Monte Carlo method.During the calculation process,a new tangent plane sampling method to calculate the response surface function(RSF)is proposed in this paper,which could make sampling points faster come close to the RSF curve,and it is proved that the calculation efficiency increases about 33%comparing with traditional method.展开更多
Considering their superior theoretical capacity and low voltage plateau,bismuth(Bi)-based materials are being widely explored for application in potassium-ion batteries(PIBs).Unfortunately,pure Bi and Bibased compound...Considering their superior theoretical capacity and low voltage plateau,bismuth(Bi)-based materials are being widely explored for application in potassium-ion batteries(PIBs).Unfortunately,pure Bi and Bibased compounds suffer from severe electrochemical polarization,agglomeration,and dramatic volume fluctuations.To develop an advanced bismuth-based anode material with high reactivity and durability,in this work,the pyrolysis of Bi-based metal-organic frameworks and in-situ selenization techniques have been successfully used to produce a Bi-based composite with high capacity and unique structure,in which Bi/Bi_(3)Se_(4)nanoparticles are encapsulated in carbon nanorods(Bi/Bi_(3)Se_(4)@CNR).Applied as the anode material of PIBs,the Bi/Bi_(3)Se_(4)@CNR displays fast potassium storage capability with 307.5 m A h g^(-1)at 20 A g^(-1)and durable cycle performance of 2000 cycles at 5 A g^(-1).Notably,the Bi/Bi_(3)Se_(4)@CNR also showed long cycle stability over 1600 cycles when working in a full cell system with potassium vanadate as the cathode material,which further demonstrates its promising potential in the field of PIBs.Additionally,the dual potassium storage mechanism of the Bi/Bi_(3)Se_(4)@CNR based on conversion and alloying reaction has also been revealed by in-situ X-ray diffraction.展开更多
为探明Φ12.5 mm 82B硬线盘条网状渗碳体形成机理,采用碳元素分析与金相组织检测相结合的方法,研究盘条径向上碳元素分布规律及不同级别网状渗碳体的显微金相组织。研究结果表明:在铸坯冷却过程中渗碳体沿奥氏体晶界析出,而w(C)高是形...为探明Φ12.5 mm 82B硬线盘条网状渗碳体形成机理,采用碳元素分析与金相组织检测相结合的方法,研究盘条径向上碳元素分布规律及不同级别网状渗碳体的显微金相组织。研究结果表明:在铸坯冷却过程中渗碳体沿奥氏体晶界析出,而w(C)高是形成网状渗碳体的主要原因,在盘条径向上w(C)呈抛物线规律分布,w(C)随距中心点距离的增大先升高后降低,在距中心点4~4.5 mm的点位上w(C)达到峰值,最高为0.827%,C偏析指数为1.02;网状渗碳体等级随着w(C)增大而升高,当网状渗碳体达到2级时,晶界处存在较强的应力集中,裂纹快速发展,盘条的质量大幅降低,引发拉拔脆断;通过优化控冷参数,1级以下级别网碳出现概率提高了4.73%,达到96.33%,钢材质量均匀性大幅提升。展开更多
基金Financial support for this research was provided by the National Natural Science Foundation of China (Grant No.52222111)。
文摘The umbilical cable is a vital component of subsea production systems that provide power,chemical agents,control signals et al.,and its requirement for reliability is exceedingly high.However,as the umbilical cable is a composite structure comprising multiple functional units,the reliability analysis of such cables involves numerous parameters that can impact calculation efficiency.In this paper,the reliability analysis of a new kind of umbilical cable with carbon fiber rod under tension is analyzed.The global dynamic analytical model is first established to determine the maximum tension load,then the local analytical model of umbilical cable including each unit are constructed by finite element method(FEM).Based on the mechanical analytical model,the reliability of umbilical cable under tension load is studied using response surface method(RSM)and Monte Carlo method.During the calculation process,a new tangent plane sampling method to calculate the response surface function(RSF)is proposed in this paper,which could make sampling points faster come close to the RSF curve,and it is proved that the calculation efficiency increases about 33%comparing with traditional method.
基金financially supported by the National Natural Science Foundation of China (22209057)the Guangdong Basic and Applied Basic Research Foundation (2021A1515010362)+1 种基金the Guangzhou Basic and Applied Basic Research Foundation (202102020995)the Open Fund of Guangdong Provincial Key Laboratory of Functional Supramolecular Coordination Materials and Applications (2020B121201005)。
文摘Considering their superior theoretical capacity and low voltage plateau,bismuth(Bi)-based materials are being widely explored for application in potassium-ion batteries(PIBs).Unfortunately,pure Bi and Bibased compounds suffer from severe electrochemical polarization,agglomeration,and dramatic volume fluctuations.To develop an advanced bismuth-based anode material with high reactivity and durability,in this work,the pyrolysis of Bi-based metal-organic frameworks and in-situ selenization techniques have been successfully used to produce a Bi-based composite with high capacity and unique structure,in which Bi/Bi_(3)Se_(4)nanoparticles are encapsulated in carbon nanorods(Bi/Bi_(3)Se_(4)@CNR).Applied as the anode material of PIBs,the Bi/Bi_(3)Se_(4)@CNR displays fast potassium storage capability with 307.5 m A h g^(-1)at 20 A g^(-1)and durable cycle performance of 2000 cycles at 5 A g^(-1).Notably,the Bi/Bi_(3)Se_(4)@CNR also showed long cycle stability over 1600 cycles when working in a full cell system with potassium vanadate as the cathode material,which further demonstrates its promising potential in the field of PIBs.Additionally,the dual potassium storage mechanism of the Bi/Bi_(3)Se_(4)@CNR based on conversion and alloying reaction has also been revealed by in-situ X-ray diffraction.
文摘为探明Φ12.5 mm 82B硬线盘条网状渗碳体形成机理,采用碳元素分析与金相组织检测相结合的方法,研究盘条径向上碳元素分布规律及不同级别网状渗碳体的显微金相组织。研究结果表明:在铸坯冷却过程中渗碳体沿奥氏体晶界析出,而w(C)高是形成网状渗碳体的主要原因,在盘条径向上w(C)呈抛物线规律分布,w(C)随距中心点距离的增大先升高后降低,在距中心点4~4.5 mm的点位上w(C)达到峰值,最高为0.827%,C偏析指数为1.02;网状渗碳体等级随着w(C)增大而升高,当网状渗碳体达到2级时,晶界处存在较强的应力集中,裂纹快速发展,盘条的质量大幅降低,引发拉拔脆断;通过优化控冷参数,1级以下级别网碳出现概率提高了4.73%,达到96.33%,钢材质量均匀性大幅提升。
