摘要
基于四极质谱交变电场和静电场中离子运动轨迹对离子源、质量分析器和离子检测器的物理参数及几何结构尺寸进行设计,研制了宽量程四极质谱计,其物理部分核心质量为2.05 kg,体积为(315×145×60)mm^(3),仪器功耗为86 W,并对质谱计的质量范围、灵敏度等核心性能指标开展实验研究。结果表明,该质谱计的质量范围为2~614 u,采用氩气测试其他性能,法拉第和倍增器的检测灵敏度分别为2.62×10^(-6)、13 A/Pa,不同质量段50%峰高处的分辨能力分别为0.95 u(m/z 2)、0.72 u(m/z 40)、0.78 u(m/z 132)和1.32 u(m/z 614),线性工作压力上限为1.39×10^(-3)Pa,仪器在4 h内的信号强度稳定性为2.6%,8 h内的质量轴稳定性为±0.1 u。该质谱计有望应用于空间探测,军事技术,食品安全等领域。
Monitoring of gas composition in long term manned confined spaces such as space stations and submarines has raised the requirement for a wide mass range quadrupole mass spectrometer.In the present work,according to the ion motion trajectory in the alternating electric field and electrostatic field,the physical parameters and structure dimensions of the ion source,mass analyzer and ion detector were designed,and a wide-range quadrupole mass spectrometer was developed at the Lanzhou Institute of Physics.The weight of its physical unit is 2.05 kg,its dimensions are approximately(315×145×60)mm^(3),and the power consumption is 86 W.The key performance indexes of the instrument were tested,and the results showed that the mass spectrometer can record mass range from 2 u to 614 u,and that the Faraday and multiplier detection sensitivity were 2.62×10^(-6),and 13 A/Pa for argon,respectively.According to the calculation of RF power supply voltage,the upper limit of mass number can reach 1048 u,but no reference material testing was conducted.The mass resolution of the spectrometer at full width half maximum(FWHM)are 0.95 u(m/z 2)、0.72 u(m/z 40)、0.78 u(m/z 132)and 1.32 u(m/z 614)in different mass segments.It was shown that the resolution of the instrument is similar in the middle mass range,but poor in small mass range and high mass range.The reason for the poor resolution at m/z 2 is that the ion mass to charge ratio is small,the axial velocity is high,so the ions have left the quadrupole field before being fully separated.There are two reasons for the poor resolution at m/z 614.One is that the ion mass charge ratio is large and the axial speed is small,which is greatly affected by the edge field at the entrance edge of the quadrupole mass analyzer.The other is that the stability becomes worse when the RF power supply outputs high voltage.These factors will lead to the poor resolution in the large mass range.The upper limit of linear working pressure is nearly 1.39×10^(-3)Pa,the instrument signal strength stability i
作者
冯天佑
成永军
陈联
董猛
王星辉
郭文
戎振华
孙雯君
FENG Tian-you;CHENG Yong-jun;CHEN Lian;DONG Meng;WANG Xing-hui;GUO Wen;RONG Zhen-hua;SUN Wen-jun(Science and Technology on Vacuum Technology and Physics Laboratory,Lanzhou Institute of Physics,Lanzhou 730000,China)
出处
《质谱学报》
EI
CAS
CSCD
北大核心
2023年第6期787-796,I0003,共11页
Journal of Chinese Mass Spectrometry Society
基金
国家自然科学基金(61901203)。
关键词
四极质谱计
宽量程
灵敏度
分辨能力
稳定性
quadrupole mass spectrometer
wide-range
sensitivity
resolution power
stability
