1、Designation:C122110Standard Test Method forNondestructive Analysis of Special Nuclear Materials inHomogeneous Solutions by Gamma-Ray Spectrometry1This standard is issued under the fixed designation C1221;the number immediately following the designation indicates the year oforiginal adoption or,in th
2、e case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the determination of the con-centration of gamma-ray emitting specia
3、l nuclear materialsdissolved in homogeneous solutions.The test method correctsfor gamma-ray attenuation by the solution and its container bymeasurement of the transmission of a beam of gamma raysfrom an external source(Refs.(1),(2),and(3).21.2 Two solution geometries,slab and cylinder,are consid-ere
4、d.The solution container that determines the geometry maybe either a removable or a fixed geometry container.This testmethod is limited to solution containers having walls or a topand bottom of equal transmission through which the gammarays from the external transmission correction source mustpass.1
5、.3 This test method is typically applied to radionuclideconcentrations ranging from a few milligrams per litre toseveral hundred grams per litre.The assay range will be afunction of the specific activity of the nuclide of interest,thephysical characteristics of the solution container,countingequipme
6、nt considerations,assay gamma-ray energies,solutionmatrix,gamma-ray branching ratios,and interferences.1.4 This standard does not purport to address all of thesafety concerns,if any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and heal
7、th practices and determine the applica-bility of regulatory limitations prior to use.For specifichazards,see Section 9.2.Referenced Documents2.1 ASTM Standards:3C1133 Test Method for Nondestructive Assay of SpecialNuclear Material in Low-Density Scrap and Waste bySegmented Passive Gamma-Ray Scanning
8、C1490 Guide for the Selection,Training and Qualification ofNondestructive Assay(NDA)PersonnelC1592 Guide for Nondestructive Assay MeasurementsC1673 Terminology of C26.10 Nondestructive Assay Meth-odsC1168 Practice for Preparation and Dissolution of PlutoniumMaterials for AnalysisE181 Test Methods fo
9、r Detector Calibration and Analysis ofRadionuclides2.2 ANSI Standards:4ANSI N15.20 Guide to Calibrating Nondestructive AssaySystemsANSI N15.35 Guide to Preparing Calibration Material forNondestructiveAssay Systems that Count Passive GammaRaysANSI N15.37 Guide to the Automation of NondestructiveAssay
10、 Systems for Nuclear Material ControlANSI N42.14 American National Standard for Calibrationand Use of Germanium Spectrometers for the Measure-ment of Gamma-Ray Emission Rates of RadionuclidesANSI/IEEE 645 Test Procedures for High-Purity Germa-nium Detectors for Ionizing Radiation3.Terminology3.1 For
11、 definitions of terms used in this test method,refer toCommittee C26.10s Terminology standard,C1673.4.Summary of Test Method4.1 Many nuclear materials spontaneously emit gamma rayswith energies and intensities characteristic of the decayingnuclide.The analysis for these nuclear materials is accom-pl
12、ished by selecting appropriate gamma rays and measuringtheir intensity to identify and quantify the nuclide.4.1.1 The gamma-ray spectrum of a portion of solution isobtained with a collimated,high resolution gamma-ray detec-tor.1This test method is under the jurisdiction ofASTM Committee C26 on Nucle
13、arFuel Cycle and is the direct responsibility of Subcommittee C26.10 on NonDestructive Assay.Current edition approved March 1,2010.Published April 2010.Originallyapproved in 1992.Last previous edition approved in 2004 as C1221 92(2004).DOI:10.1520/C1221-10.2The boldface numbers in parentheses refer
14、to the list of references at the end ofthis test method.3For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact ASTM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.4Available
15、 from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 4.1.2 Count-rate-dependent losses are determined and cor-rections are made for
16、these losses.4.1.3 A correction factor for gamma-ray attenuation in thesolution and its container is determined from the measurementof the transmitted intensity of an external gamma-ray source.The gamma rays from the external source have energies closeto those of the assay gamma rays emitted from the solution.Figs.1 and 2 illustrate typical transmission source,solution,and detector configurations.Gamma rays useful for assays of235U and239Pu are listed in Table 1.4.1.4 The relationship between th