Introduction
TThe Environmental Radioactivity Laboratory currently operates two suits of low-background well-type High-Purity Germanium (HPGe) radiation detection system (GWL-120-15-LB-AWT, AMETEK, USA) that are accredited to measure a series of radionuclides for a range of applications in environmental research and monitoring. To ensure detection limits are maintained as low as possible, monthly background checks are undertaken alongside routine monitoring of the quality of each detector’s signal. Energy and efficiency calibration is accomplished by measuring the spectrum of a source with known full-peak energies.
1. Advantages of the low-background HPGe system:
High absolute counting efficiency:>50 %;
BroadSpectroscopy: 10-10 MeV;
Excellent energy resolution: FWHMat 1.33-MeV photons from 60Co≤ 2.3 keV;
Low radioactive background: 50 KeV to 2000 KeV ≤ 1.2 cps.
Small sample size required: 8-10 g;
Minimum artificial error;
2. Main applications:
Gamma-ray spectrometry is widely applied as a tool for the assay of radioactive source material to identify the isotopes present (e.g. 210Pb,137Cs,226Ra,228Ra and 234Th) and charact
erize radiation fields. Applications include: anthropogenic radioactive contamination monitoring, natural processes tracing, sedimentation rates calculating, etc.
3. Charges:
Each sample will be tested for 24 h to achieve adequate uncertainty level, and the charge is 300 RMB for Tongji University, and 600 RMB for others
4. Pretreatments:
Only sediment or soil samples were currently accepted
Water content of each sample is suggested to be tested in advance;
Dry grinding of materials till no obvious grains;
Sample size better larger than 8-10 g;
Please inform the lab of highly radioactive samples.
Contact Person：Prof. Daidu Fan
Tel: 021-65989073;
E-mail:ddfan@tongji.edu.cn