ASTM E263-00

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: E 263 – 00
Standard Test Method for
Measuring Fast-Neutron Reaction Rates by Radioactivation
of Iron
This standard is issued under the fixed designation E263; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
This standard has been approved for use by agencies of the Department of Defense.
1. Scope metric Monitors for Reactor Vessel Surveillance,
E706(IIIA)
1.1 This test method describes procedures for measuring
54 54
E1018 Guide for Application of ASTM Evaluated Cross
reaction rates by the activation reaction Fe (n,p) Mn .
Section Data File, Matrix E706(IIB)
1.2 Thisactivationreactionisusefulformeasuringneutrons
withenergiesaboveapproximately2.2MeVandforirradiation
3. Terminology
times up to about 3 years (for longer irradiations, see Practice
3.1 Definitions:
E261).
3.1.1 Refer to ASTM Standard E170 for definitions of
1.3 With suitable techniques, fission-neutron fluence rates
8 −2 −1 terms relating to radiation measurements and neutron dosim-
above 10 cm ·s can be determined. However, in the pres-
etry.
enceofahighthermal-neutronfluencerate(forexample,>2 3
14 −2 −1 54
10 cm ·s ) Mn depletion should be investigated.
4. Summary of Test Method
1.4 Detailed procedures for other fast-neutron detectors are
4.1 High-purity iron is irradiated in a neutron field, thereby
referenced in Practice E261.
54 54 54
producing radioactive Mn from the Fe (n,p) Mn activa-
1.5 This standard does not purport to address all of the
tion reaction.
safety concerns, if any, associated with its use. It is the
4.2 The gamma rays emitted by the radioactive decay of
responsibility of the user of this standard to establish appro-
Mn are counted in accordance with Methods E181 and the
priate safety and health practices and determine the applica-
reaction rate, as defined by Practice E261, is calculated from
bility of regulatory limitations prior to use.
the decay rate and irradiation conditions.
2. Referenced Documents 4.3 Radioassay of the Mn activity may be accomplished
by directly counting the irradiated iron dosimeter, or by first
2.1 ASTM Standards:
chemically separating the Mn activity prior to counting.
D1193 Specification for Reagent Water
4.4 The neutron fluence rate above about 2.2 MeVcan then
E170 Terminology Relating to Radiation Measurements
be calculated from the spectral-weighted neutron activation
and Dosimetry
cross section as defined by Practice E261.
E181 Test Methods for Detector Calibration and Analysis
of Radionuclides
5. Significance and Use
E261 Practice for Determining Neutron Fluence Rate, Flu-
5.1 Refer to Guide E844 for guidance on the selection,
ence, and Spectra by Radioactivation Techniques
irradiation, and quality control of neutron dosimeters.
E844 Guide for Sensor Set Design and Irradiation for
5.2 Refer to Practice E261 for a general discussion of the
Reactor Surveillance, E706(IIC)
determination of fast-neutron fluence rate with threshold de-
E944 Guide for Application of Neutron Spectrum Adjust-
tectors.
ment Methods in Reactor Surveillance, (IIA)
5.3 Pure iron in the form of foil or wire is readily available
E1005 TestMethodforApplicationandAnalysisofRadio-
and easily handled.
5.4 Fig. 1 shows a plot of cross section as a function of
54 54
neutron energy for the fast-neutron reaction Fe (n,p) Mn .
ThistestmethodisunderthejurisdictionofASTMCommitteeE-10onNuclear
(1) This figure is for illustrative purposes only to indicate the
Technology and Applications and is the direct responsibility of Subcommittee
54 54
range of response of the Fe (n,p) Mn reaction. Refer to
E10.05 on Nuclear Radiation Metrology.
Current edition approved Jan. 10, 2000. Published April 2000. Originally
published as E263–65T. Last previous edition E263–93.
2 4
Annual Book of ASTM Standards, Vol 11.01. Theboldfacenumbersinparenthesesrefertothelistofreferenceslocatedatthe
Annual Book of ASTM Standards, Vol 12.02. end of this test method.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
E 263
6.2 Precision Balance, able to achieve the required accu-
racy.
6.3 Digital Computer, useful for data analysis (optional).
6.4 Cylinder, borosilicate glass, about 25-mL capacity,
equipped with stopcock and funnel. This apparatus is illus-
trated in Fig. 2.
6.5 Beakers,borosilicateglass,50mL; volumetric flasks,25
and 50 mL, and volumetric pipets, 1 mL.
7. Reagents and Materials (Note 1)
7.1 Purity of Reagents—Reagent grade chemicals shall be
used in all tests. Unless otherwise indicated, it is intended that
all reagents shall conform to the specifications of the Com-
54 54
FIG. 1 Fe (n,p) Mn Cross Section
merce on Analytical Reagents of the American Chemical
Society, where such specifications are available. Other grades
may be used, provided it is first ascertained that the reagent is
Guide E1018 for descriptions of recommended tabulated
of sufficiently high purity to permit its use without lessening
dosimetry cross sections.
the accuracy of the determination.
5.5 Mn has a half-life of 312.12 days (2) and emits a
7.2 Purity of Water— Unless otherwise indicated, refer-
gamma ray with an energy of 834.8 eV. (3) ences to water shall be understood to mean reagent water
5.6 Competing activities from thermal or fast neutrons are
conforming to Specification D1193.
56 59 60
7.3 Anion Exchange Resin, strongly basic type, 100 to 200
2.58-h Mn , 44.5-d Fe , and 5.271-y Co . (Consult
mesh size.
reference 2 for more precise values currently accepted for the
halflives.)Interferencefrom Mncanbeeliminatedbywaiting
48 h before counting. Although chemical separation of Mn
“ReagentChemicals,AmericanChemicalSocietySpecifications,”Am.Chemi-
from the irradiated iron is the most effective method for
cal Soc., Washington, DC. For suggestions on the testing of reagents not listed by
59 60 54
eliminating Fe and Co , direct counting of iron for Mn is
theAmerican Chemical Society, see “Analar Standards for Laboratory Chemicals,”
BDH Ltd., Poole, Dorset, U.K., and the “United States Pharmacopeia.”
possibleusinghigh-resolutiondetectorsystemsorunfoldingor
stripping techniques, especially if the dossimeter was covered
withcadmiumorboronduringirradiation.Alteringtheisotopic
composition of the iron dosimeter is another useful technique
for eliminating interference from extraneous activities when
direct sample counting is to be employed.
5.7 Thevaporpressuresofmanganeseandironaresuchthat
manganesediffusionlossesfromironcanbecomesignificantat
temperatures above about 700°C. Therefore, precautions must
be taken to avoid the diffusion loss of Mn from iron
dosimeters at high temperature. Encapsulation in quartz, vana-
dium, or other materials will contain the manganese for
temperatures up to about 900°C.
5.8 Sections6,7&8thatfollowwerespecificallywrittento
describe the method of chemical separation and subsequent
countingofthe Mnactivity.Whenoneelectstocounttheiron
dosimeters directly those portions of Sections 6,7&8 that
pertain to radiochemical separation should be disregarded.
NOTE 1—Thefollowingportionsofthistestmethodapplyalsotodirect
sample-counting methods: 6.1-6.3, 7.4, 7.9, 7.10, 8.1-8.5, 8.18, 8.19, and
9-12.
6. Apparatus (Note 1)
6.1 NaI(Tl) or High–Resolution Gamma-Ray Spectrometer,
becauseofitshighresolution,thegermaniumdetectorisuseful
when contaminant activities are present. See Methods E181
and E1005.
Reference (3) gives a value of 834.848 keVas the most precise value currently
accepted for the Mn decay gamma-ray energy. FIG. 2 Ion-Exchange Separation Apparatus
E 263
7.4 Iron Foil or Wire, high purity. 8.6 After irradiation, dissolve the sample in 10 mL of
concentrated hydrochloric acid to which 2 drops of nitric acid
7.5 Hydrochloric Acid (sp gr 1.19, 1190 kg/m )—
have been added. The solution may be heated gently to hasten
Concentrated hydrochloric acid (HCl).
dissolution.
7.6 Hydrochloric Acid (1 + 3)—Mix 1 volume of concen-
8.7 After dissolution is complete, transfer the solution with
trated HCl (sp gr 1.19) with 3 volumes of water.
washing to a 25-mLvolumetric flask. Wash only with concen-
7.7 Manganese Carrier Solution (10 mg MnCl /cm ).
trated hydrochloric acid and use this also in diluting to the
7.8 Nitric Acid (sp gr 1.42, 1420 kg/m )—Concentrated
calibration mark on the volumetric flask.
nitric acid (HNO ).
3 8.8 Prepareaslurryofanionexchangeresinwithdistilledor
7.9 Encapsulating Materials—Brass,stainlesssteel,copper, deionized water and pour it into the ion exchange column
aluminum, quartz, or vanadium have been used as primary apparatus (see Fig. 2) to a height of 100 mm. Place a
encapsulating materials. The container should be constructed glass-wool plug above the resin and keep the column under
liquid at all times.
in such a manner that it will not create significant flux
perturbation and that it may be opened easily, especially if the 8.
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