一种新型四极杆质谱仪数据采集系统的研制  

Development of a Novel Data Acquisition System for Quadrupole Mass Spectrometer

作　　者：王愉天 陈吉文 Wang Yutian;Chen Jiwen(North China University of Technology,Beijing 100144,China)

机构地区：[1]北方工业大学,北京100144

出　　处：《实验与分析》2024年第2期53-59,共7页LABOR PRAXIS

摘　　要：电子倍增器是目前大多数四极杆质谱仪采用的检测器方案,这种检测器输出的是微弱电流信号,这种微弱电流信号在后续的处理、采集过程中容易被噪声信号干扰,导致仪器信噪比降低。针对传统四极杆质谱仪数据采集系统易受干扰且信噪比较低的问题,研制了一种新型数据采集系统,对于模拟模式,使用VFC(电压-频率转换Voltage-Frequency Conversion)方案替代了传统的ADC方案;对于脉冲模式,研制了一种新型脉冲信号调理电路,可将脉冲模式输出的不规则电流脉冲信号转换为幅值、脉宽信号一致的电压脉冲以方便采集。在本团队自制的ICP-MS样机平台上利用本套系统测试含有9Be、59Co、89Y、115In、140Ce、209Bi的梯度浓度标准溶液,实验结果表明,在ICP源强烈的电磁干扰影响下,新型数据采集系统的稳定性、精度等关键指标满足仪器需求。The electron multiplier is currently the preferred detector solution for most quadrupole mass spectrometers.However,the detector outputs a weak current signal,which is prone to interference from noise signals during subsequent processing and acquisition,resulting in a decrease in the instrument's signal-to-noise ratio.Aiming at the issues of susceptibility to interference and low signal-to-noise ratio in traditional quadrupole mass spectrometer data acquisition systems,a novel data acquisition system has been developed.For analog mode,the traditional ADC scheme is replaced by the VFC(Voltage-Frequency Conversion)solution.For pulse mode,a novel pulse signal conditioning circuit is developed,which can convert the irregular current pulse signals output in pulse mode into voltage pulses with consistent amplitude and pulse width for convenient acquisition.Utilizing this system on our self-made ICP-MS prototype platform to test gradient concentration standard solutions containing 9Be,59Co,89Y,115In,140Ce,and 209Bi,the experimental results demonstrate that under the strong electromagnetic interference of the ICP source,the stability,accuracy,and other key indicators of the novel data acquisition system meet the instrument's requirements.

关 键 词：四极杆质谱仪 数据采集系统 VFC 脉冲信号调理 

分 类 号：O657[理学—分析化学]