One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific object...One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water.展开更多
建立基于前处理技术结合液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)对鲤鱼基质中苦参碱和氧化苦参碱残留量测定的分析方法.样品采用乙腈均质提取的萃取方式,用硫酸钠作为除水剂,样品经过C18色谱柱...建立基于前处理技术结合液相色谱-串联质谱法(liquid chromatography-tandem mass spectrometry,LC-MS/MS)对鲤鱼基质中苦参碱和氧化苦参碱残留量测定的分析方法.样品采用乙腈均质提取的萃取方式,用硫酸钠作为除水剂,样品经过C18色谱柱分离,以水-乙腈为流动相,基质匹配标准曲线外标法定量.苦参碱和氧化苦参碱在质量浓度范围1—50 ng·mL^(−1)内,具有良好的线性关系,相关系数R^(2)均大于0.99.苦参碱方法检出限为0.21 ng·mL^(−1),定量限为0.69 ng·mL^(−1);氧化苦参碱方法检出限为0.17 ng·mL^(−1),定量限为0.52 ng·mL^(−1).添加浓度水平1.0、2.0、5.0 ng·mL^(−1),平均回收率为72.5%—108.7%,相对标准偏差(relative standard deviation,RSD,n=6)为4.2%—8.2%.苦参碱和氧化苦参碱的基质效应均表现为抑制.该方法前处理方法简单,灵敏度高,稳定性好,适合鲤鱼基质苦参碱和氧化苦参碱残留量的测定,同时为后续同类样品检测提供参考,也为今后相关标准制定提供数据积累.展开更多
基金Supported by the National Natural Science Foundation of China(42474239,41204128)China National Space Administration(Pre-research project on Civil Aerospace Technologies No.D010301)Strategic Priority Research Program of the Chinese Academy of Sciences(XDA17010303)。
文摘One of the detection objectives of the Chinese Asteroid Exploration mission is to investigate the space environment near the Main-belt Comet(MBC,Active Asteroid)311P/PANSTARRS.This paper outlines the scientific objectives,measurement targets,and measurement requirements for the proposed Gas and Ion Analyzer(GIA).The GIA is designed for in-situ mass spectrometry of neutral gases and low-energy ions,such as hydrogen,carbon,and oxygen,in the vicinity of 311P.Ion sampling techniques are essential for the GIA's Time-of-Flight(TOF)mass analysis capabilities.In this paper,we present an enhanced ion sampling technique through the development of an ion attraction model and an ion source model.The ion attraction model demonstrates that adjusting attraction grid voltage can enhance the detection efficiency of low-energy ions and mitigate the repulsive force of ions during sampling,which is influenced by the satellite's surface positive charging.The ion source model simulates the processes of gas ionization and ion multiplication.Simulation results indicate that the GIA can achieve a lower pressure limit below 10-13Pa and possess a dynamic range exceeding 10~9.These performances ensure the generation of ions with stable and consistent current,which is crucial for high-resolution and broad dynamic range mass spectrometer analysis.Preliminary testing experiments have verified GIA's capability to detect gas compositions such as H2O and N2.In-situ measurements near 311P using GIA are expected to significantly contribute to our understanding of asteroid activity mechanisms,the evolution of the atmospheric and ionized environments of main-belt comets,the interactions with solar wind,and the origin of Earth's water.
