摘要
该标准装置由２台４πγ高气压电离室（ＩＣ／２Ｃ（１．０ＭＰａ），ＩＧ１２／Ａ２０（２．０ＭＰａ））、微电流测量系统、铅屏蔽室、标准样品瓶和一套长寿命监督源（￣（２２６）Ｒａ）组成。２台４πγ高气压井型电离室，用于系统的互检。装置具有测量快速、长期稳定性好和量程宽等特点。
The standard consists of 4πγ pressurized ionization chambers(IC/2C(1.0MPa)and IG12/A20(2.0MPa)),small current measurement system,standard bottles,one set of long-live refe-rence sources(￣(226)Ra),and lead shields. It has the following advantages:1)long-term stability lessthan 0.1%per year;2)fast speed for activity measurement;3)allow the direct measurement ac-tivity of solutions in ampoules;4)permit measurement over a fong range of activity(10￣4-10￣(10)Bq).For short-live nuclides,it is necessary to know the efficiency of the ionization chamber. Thecalibration factors can be calculated according to the efficiency curve and the probability of γ-rayemission. The calibration factors of some nuclides are calculated and the deviation of the calcula-tion factors from experiment is less than ± 3%, The half-life of￣(99)Tc￣m is measured, the result is6.0053±0.0018h.
出处
《原子能科学技术》
EI
CAS
CSCD
北大核心
1994年第3期231-235,共5页
Atomic Energy Science and Technology
关键词
4πγ高气压电离室
微电流测量
刻度
效率曲线
4πγ high presure ionization chamber
Micro-current measurement
Calibration
Efficiency curve
