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[en] Based on the analysis of the data formats of HPGe Gamma-ray Spectra, one data format transformation software for HPGe γ spectra has been developed on the platform for Microsoft visual C++ 6.0. Using this software, different data formats of analysis software for HPGe gamma-ray spectra can be transformed mutually. (authors)

[en] The paper introduces the method of dating the zero time by utilizing the activity ratio of two fission products in no-isobaric or parent-daughter fission products in isobaric. The method was applied to determine the zero time of filter sample in the CTBT radionuclide laboratories intercomparison from 2001 to 2004. The calculated results are very good agreement with referent values in the range of uncertainty. (authors)

[en] The paper introduces the process of 2005 CTBT Inter comparison of aerosol sample. After elaborate analysis 13 radio nuclides in five reference spectra was identified,and calculated activity of all the radio nuclides are very good agreement with referent values in the range of uncertainty. (authors)

[en] Based on the process of 2003 Comprehensive Nuclear-Test-Ban Treaty (CTBT) intercomparison of atmospheric particle filter sample that organized by the organization, the structure of HPGe detector and the geometry of sample used in the comparison were described in detail. The peak efficiency and total efficiency of the filter sample were simulated by using the MCNP. The simulation results are agreed with referenced values in 3.5% and 6.5%, respectively. This work makes quantitative analysis of sample more accurate. (authors)

[en] Monitoring radioactive Xenon concentration in air is effective way to screen nuclear event in CTBT verification regime. This article introduces the theory and process of radioactive Xenon measurement by HPGe gamma spectrometer and researches MDA trend of Xenon isotope base on background data. (authors)

[en] A Compton-suppress spectrometer was introduced and its performance was tested. The measurement geometry position of Φ20mm plate source, Φ50mm and Φ70mm filter source were optimized. (authors)

[en] The β-γ coincidence technique is a kind of the key important method to detect radioactive xenon isotopes for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). This paper describes noble gases memory effects of β-γ coincidence detector. Xenon memory effects were measured and its influence on detector's minimum detectable activity (MDA) was evaluated. The methods of reducing xenon memory effects were studied. In conclusion, aluminium coated plastic scintillator and YAP scintillator can remarkably decrease xenon memory effects. (authors)

[en] The radioactivity concentrations of ⁷Be, ²¹²Pb and ²¹⁴Pb in the atmosphere of Xi'an suburb were determined from April 2002 to April 2003. A high-volume air sampler and a high resolution gamma-ray spectrometer were used to measure the radioactivity. The annual average concentrations of ⁷Be, ²¹²Pb and ²¹⁴Pb were 6.68 x 10^-3 Bq·m^-3, 0.65 Bq/m³ and 16.06 Bq·m^-3, respectively. The ⁷Be levels were higher in spring than those in other seasons, with a maximum concentration of 16.64 x 10^-3 Bq·m^-3. They reflected obvious seasonal trends. The concentrations of ²¹²Pb and ²¹⁴Pb have strong seasonal trends. The maximum concentrations were 1.71 Bq·m^-3 for ²¹²Pb and 50.11 Bq·m^-3 for ²¹⁴Pb in winter. Precipitation is a major factor affecting the concentrations of ⁷Be, ²¹²Pb and ²¹⁴Pb, the monthly mean values reach minimum in August, when precipitation is the biggest of all the months. Artificial radionuclides, such as ¹³⁷Cs, have not been found. (authors)

[en] This paper reports the brief process and results of radioxenon monitoring and analysis in Beijing following the Fukushima Daiichi nuclear power plant accident. The accident and release of volatile radionuclides were caused by 9.0 magnitude earthquake and tsunami on March 11, 2011. The maximum concentrations of ¹³³Xe and ^131mXe were in excess of 0.90 Bq.m⁻³ and 0.047 Bq.m⁻³, respectively. The activity ratio of ^131mXe to ¹³³Xe and the dynamic trend of ¹³³Xe activity concentration were analyzed