Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine, Jan 29, 2015
(123)I is widely used for radiodiagnostic procedures. It is produced by reaction of (124)Xe (p,2n... more (123)I is widely used for radiodiagnostic procedures. It is produced by reaction of (124)Xe (p,2n) (123)Cs →(123)Xe →(123)I in cyclotrons. (121)Te and (125)I appear in a photon energy spectrum as impurities. An activity of (121)Te was calibrated absolutely by sum-peak method and its photon emitting probability was estimated, whose results were consistent with published results.
... CIDB updated the scoring system for the CONQUAS in 1995 to allow for more tests on materials ... more ... CIDB updated the scoring system for the CONQUAS in 1995 to allow for more tests on materials and functional ... The quality of a structural frame is of paramount importance as it will affect the long-term ... All assessments for structural works are made at the time of construction. ...
This work presents the experience of the National Laboratory for Ionizing Radiation Metrology (LN... more This work presents the experience of the National Laboratory for Ionizing Radiation Metrology (LNMRI) in the implementation of the requirements of the Mutua l Recognition Arrangement (MRA) signed by 38 National Institutes of Metrology (NMI) in 1999. The degree o f equivalence of activity reported by Bureau Internat ional des Poids et Mesures (BIPM) in the Key Comparison Data Base (KCDB), the main data of a specific radionuclide li sted in the Calibration and Measurement Capabilities (CMC) and the implementation of a quality system are informed .
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012
ABSTRACT A solution containing the positron emitter 22Na has been absolutely standardized using t... more ABSTRACT A solution containing the positron emitter 22Na has been absolutely standardized using the 4πβ–γ coincidence counting method and the sum-peak spectrometry counting method. In the 4πβ–γ coincidence method two ways for the activity concentration measurements were used: gating on the 1275 keV photopeak and on the 1786 keV sum-peak where the knowledge of the β+-branching ratio is required. In the sum-peak method the measurements were carried out using three experimental arrangements: the first composed by a well type 5 in.×5 in. NaI(Tl) scintillation crystal, the second by a 3 in.×3 in. NaI(Tl) scintillation crystal placed on the top of the first, resulting in a 4π counting geometry and the third arrangement is a high purity coaxial germanium detector. The results that are obtained by these two methods are compatible within the standard uncertainty values with a coverage factor of k=2 (∼95% of the confidence level). This means that the sum-peak counting with its more simple experimental setup than the complex coincidence 4πβ–γ counting system gives consistent results for the activity standardization of 22Na with smaller uncertainties. Besides, the time period involved to attain the result of the standardization was quite shorter than the coincidence measurements used in this work.
Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine, 2014
The activity concentration of a solution of (99)Tc was absolutely determined by liquid scintillat... more The activity concentration of a solution of (99)Tc was absolutely determined by liquid scintillation measurements based on the triple-to double-coincidence ratio method (TDCR) and compared with the results given by 4πβ(LS)-γ(NaI) live-timed anticoincidence (with extending dead-time) and classical 4πβ(PC)-γ(NaI) coincidence counting systems based on using (60)Co as the efficiency-tracing radionuclide. The results of anticoincidence and coincidence counting are, respectively, 0.18% and 0.66% higher than the result from TDCR measurements, but they are consistent within uncertainties.
Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine, Jan 29, 2015
(123)I is widely used for radiodiagnostic procedures. It is produced by reaction of (124)Xe (p,2n... more (123)I is widely used for radiodiagnostic procedures. It is produced by reaction of (124)Xe (p,2n) (123)Cs →(123)Xe →(123)I in cyclotrons. (121)Te and (125)I appear in a photon energy spectrum as impurities. An activity of (121)Te was calibrated absolutely by sum-peak method and its photon emitting probability was estimated, whose results were consistent with published results.
... CIDB updated the scoring system for the CONQUAS in 1995 to allow for more tests on materials ... more ... CIDB updated the scoring system for the CONQUAS in 1995 to allow for more tests on materials and functional ... The quality of a structural frame is of paramount importance as it will affect the long-term ... All assessments for structural works are made at the time of construction. ...
This work presents the experience of the National Laboratory for Ionizing Radiation Metrology (LN... more This work presents the experience of the National Laboratory for Ionizing Radiation Metrology (LNMRI) in the implementation of the requirements of the Mutua l Recognition Arrangement (MRA) signed by 38 National Institutes of Metrology (NMI) in 1999. The degree o f equivalence of activity reported by Bureau Internat ional des Poids et Mesures (BIPM) in the Key Comparison Data Base (KCDB), the main data of a specific radionuclide li sted in the Calibration and Measurement Capabilities (CMC) and the implementation of a quality system are informed .
Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2012
ABSTRACT A solution containing the positron emitter 22Na has been absolutely standardized using t... more ABSTRACT A solution containing the positron emitter 22Na has been absolutely standardized using the 4πβ–γ coincidence counting method and the sum-peak spectrometry counting method. In the 4πβ–γ coincidence method two ways for the activity concentration measurements were used: gating on the 1275 keV photopeak and on the 1786 keV sum-peak where the knowledge of the β+-branching ratio is required. In the sum-peak method the measurements were carried out using three experimental arrangements: the first composed by a well type 5 in.×5 in. NaI(Tl) scintillation crystal, the second by a 3 in.×3 in. NaI(Tl) scintillation crystal placed on the top of the first, resulting in a 4π counting geometry and the third arrangement is a high purity coaxial germanium detector. The results that are obtained by these two methods are compatible within the standard uncertainty values with a coverage factor of k=2 (∼95% of the confidence level). This means that the sum-peak counting with its more simple experimental setup than the complex coincidence 4πβ–γ counting system gives consistent results for the activity standardization of 22Na with smaller uncertainties. Besides, the time period involved to attain the result of the standardization was quite shorter than the coincidence measurements used in this work.
Applied radiation and isotopes : including data, instrumentation and methods for use in agriculture, industry and medicine, 2014
The activity concentration of a solution of (99)Tc was absolutely determined by liquid scintillat... more The activity concentration of a solution of (99)Tc was absolutely determined by liquid scintillation measurements based on the triple-to double-coincidence ratio method (TDCR) and compared with the results given by 4πβ(LS)-γ(NaI) live-timed anticoincidence (with extending dead-time) and classical 4πβ(PC)-γ(NaI) coincidence counting systems based on using (60)Co as the efficiency-tracing radionuclide. The results of anticoincidence and coincidence counting are, respectively, 0.18% and 0.66% higher than the result from TDCR measurements, but they are consistent within uncertainties.
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