Abstract:
Due to the small relative mass difference between
m/z 308 and m/z 309, simultaneous data collection was not possible using conventional multi-collection mass spectrometers. To conduct multi-collector measurements of m/z 308 (133Cs210B16O2+) and m/z 309 (133Cs211B16O2+), the Faraday cups were configured to measure m/z 308 and m/z 309 array with zoom optics. We utilize thermal ionization mass spectrometry (Trion) to perform automatic and high-precision determination of boron isotope using static multicollection of Cs2BO2+ ions. The research has been performed to investigate the impact of ion current and filament current on the accuracy and reproducibility of boron isotope measurements for NIST 951 Standard, giving values of 11B/10B were in the range of 4.052 63—4.053 38， when ion current varied 0.1—10 V and filament current varied 1 150—1 350 mA.The phenomenon of this study was filament current. With the higher of filament current, the ion current was corresponding to be higher. Based on this discovery, we have established the conditions for precise boron isotopic measurement using the multicollection technique by automatic mode. The proposed method was used for the determination of NIST 951 H3BO3 and natural samples. The results show that the automatic mode and manual mode has same precision and accuracy. And this technique enables us to do speedy analysis of boron isotopes and greatly improve the efficiency.
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