射线英语.docx
- 文档编号:10288485
- 上传时间:2023-02-09
- 格式:DOCX
- 页数:54
- 大小:51.01KB
射线英语.docx
《射线英语.docx》由会员分享,可在线阅读,更多相关《射线英语.docx(54页珍藏版)》请在冰豆网上搜索。
射线英语
NondestructiveTestingEncyclopedia
RT
GlossaryofTermsforRadiographicTesting
Absorbdose:
Theamountofenergyimpartedbyionizingradiationperunitmassofirradiatedmatter.Indicatedby"rad";1rad=0.01j/kg.SIunitsis"gray";1gray=1J/kg.
Seealsogray(Gy),SIunits
Absorbdoserate:
theabsorbeddoseperunitoftime;rad/sorasSIunitgray/s.
Seealsogray(Gy),Kerma
Absorption:
Theprocesswherebytheincidentparticlesorphotonsofradiationarereducedinanumberorenergyastheypassthroughmatter,i.e.theenergyoftheradiationbeamisattenuated.Notethatthetotalattenuationisthesumofthecomponentsduetophotoelectricabsorption,Rayleighscattering,Comptonscatteringandpairproduction.
SeealsoAttenuation
Acceleratingpotential:
ThedifferenceinelectricpotentialbetweenthecathodeandanodeinanX-raytubethroughwhichachargedparticleisaccelerated,usuallyspezifiedinunitsofkVorMV.
Activity:
Thenumberofnucleartransitionsoccurringinagivenquantityofradioactivematerialperunitoftime.Forexampleonedisintegration/secondisabecquerel(Bq),whichhasreplacedcurie(Ci)asthestandardunitofactivity.
Acuteradiationsyndrom:
Theimmediateeffectsofashortterm,wholebodyoverexposureofapersontoionizingradiation.Theseeffectsincludenauseaandvomiting,malaise,increasetemerature,andbloodchange.
Ageingfog:
Theincreaseinopticaldensityonanunexposedfilm,measuredafterprocessing,duetolong-termstorage.
Alphaparticle:
Thenucleiofaheliumatom(withtwoneutronsandtwoprotonseach)thataredischargedbyradioactivedecayofmanyheavyelements,suchasuranium-238andplutonium-239.
Anode:
ThepositiveelectrodeofanX-raytube.InanX-raytube,theanodecarriesthetarget.
Anodecurrent:
TheelectronspassingfromthecathodetotheanodeinanX-raytube.Thereisasmalllossincurredbythebackscattedfraction.
Artefact(falseindication):
Aspuriousindicationonaradiographarisinge.g.fromfaultsinthemanufacturing,handling,exposingorprocessingofafilm.
Attenuation:
ThereductioninintensityofabeamofX-orgammaradiationduringitspassagethroughmattercausedbyabsorptionandscattering.
Averagegradient:
Theslopeofalinedrawnbetweentwospecifiedpointsonthesensitometriccurve.
Backscatter/backscatteredradiation:
Radiationwhichisscatteredatanangleofmorethan90?
inrelationtothedirectionoftheincidentbeam.
Beamangle:
Theanglebetweenthecentralaxisoftheradiationbeamandtheplaneofthefilm.
Becquerel:
TheSIunitofactivityequaltoonedisintegrationpersecond.[37billion(3.7x1010)becquerels=1curie(Ci)].
Betatron:
AmachineinwhichelectronsareacceleratedinacircularorbitbeforebeingdeflectedontoatargettoproducehighenergyX-rays.Thistypeofequipmentusuallyoperatesatenergiesbetween10and31MEV.
Blockingmedium:
Aabsorptivematerialsurroundingspecimensorcoveringtheirsectionsusedtoreducetheeffectofscatteredradiationonthefilmorontheimagedetector.
SeealsoMasking
Build-upfactor:
Theratiooftheintensityofthetotalradiationreachingapoint,totheintensityoftheprimaryradiationreachingthesamepoint.
Calibrateddensitystepwedge:
Apieceoffilmhavingaseriesofdifferentopticaldensitieswhichhavebeencalibratedtobeusedasreferencedensities.
Cassette:
Arigidorflexiblelight-tightcontainerforholdingradiographicrecordingmedia(filmorpaper)withorwithoutintensifyingscreens,duringexposure.
Cathode:
ThenegativeelectrodeofanX-raytube.
Characteristiccurve:
Acurve(ofafilm)showingtherelationshipbetweenthecommonlogarithmofexposure,logK,andtheopticaldensity,D.AlsocalledtheD-logEcurveortheHandDcurve.
Clearingtime:
Thetimeneededforthefirststageoffixingofafilm,duringwhichthecloudinessdisappears.
Collimation:
Thelimitingofabeamofradiationtoaformofrequireddimensions,bytheuseofdiaphragmsmadeofabsorbingmaterial.
Collimator:
Adevicemadefromradiationabsorbentmaterialsuchasleadortungsten,designedtolimitanddefinethedirectionandangulardivergenceoftheradiationbeam.
Comptonscatter:
AformofscatteringcausedbyaphotonofX-orgammaradiationinteractingwithanelectronandsufferingareductionofenergy,thescatteredradiationbeingemittedatanangletotheincidentdirection.Sincetheejectedelectronhasashortrangeinmostmaterials,itisnotconsideredpartofthescatteredradiation.Forradiationintheenergyrange100keVto10MeV,itisthemainfactorcontributingtoradiationattenuation.
Computerizedtomography(CT):
Aprocedurebywhichanimageofthedetailinachosenplane,perpendiculartotheaxisofthespecimen,iscomputedfromalargenumberofX-rayabsorptionmeasurementsmadefrommanydirectionsperpendiculartotheaxis.Thisiscomputerizedaxialtomographyanddoesnotapplytoothermeansofperformingtomography.
Constantpotentialcircuit:
AnelectronicconfigurationwhichisdesignedtoapplyandmaintainasubstantiallyconstantpotentialwithinanX-raytube.
Continuousspectrum:
TherangeofwavelengthsorquantumenergiesgeneratedbyanX-rayset.
Contrast:
See"Imagecontrast","Radiationcontrast","Objectcontrast"and"Visualcontrast".
Contrastmedium:
Anysuitablesubstance,solidorliquid,appliedtoamaterialbeingradiographedtoenhanceitsradiationcontrastintotalorinpart.
Contrastsensitivity(thicknesssensitivity):
Thesmallestthicknesschangeinspecimenwhichproducesadiscemiblechangeinopticaldensityona:
radiogragphic(orradioscopiclimage,usuallyexpressedasaperceatageofthetotalspecimenthickness.'
Curie(Ci):
Theunitusedtodescribetheintensityofradioactivityinasampleofmaterial.Thecurieisequalto37billion(3.7x1010)disintegrationspersecond,whichisapproximatelytheactivityof1gramofradium.TheBecquerel(Bq)hasreplacedtheCiintheSIsystem.TheBecquerel(Bq)is1disintegrationpersecond.
Decaycurve:
Tftw,activityofaradioissetope;,,plottedaalInsttime,usuallyAsaIdg/lInoar.jelationship.
Densitometer:
Adeviceforthemeasurement,oftheopticaldensityofaradiographicfilmorreflectivedensityofaphotographicprint.
Development(ofafilmorpaper):
chemicalorphysicalprocesswhichconvertsalatentimageintoavisibleimage.
Diffractionmottle:
Asuperimposedpatternonaradiographicimtoeduetodiffractionoftheincidentradiationbythematerialstructure.
Doseraterreter:
AninstrumentforthemeasurementofX-orgammaradiationdose-rate.
Dosemeter(dosimeter):
AninstrumentformeasuringtheaccumulateddoseofX-orgammaradiation.
Dualfocustube:
AnX-raytubewithtwodifferentsizesoffocus.
Dublexwireimagequalityindicator:
Animagequalityindicatorspecificallydesignedtoassesstheoverallunsharpnessofaradiographicimageandcomposedofaseriesofpairsofwireelementsmadeofhighdensitymetal.
Edge-blockingmaterial:
Materialappliedaroundaspecimenorincavitiestoobtainamoreuniformabsorption,toreduceextraneousscatteredradiation,andtopreventlocalover-exposure,e.g,fineleadshot(seealso"Blockingmedium").
Equalizingfilter(beamflattener):
AdeviceusedtoequalizetheintensityacrosstheprimaryX-raybeaminmegavoltageradiographyandsoextendtheusefulfieldsize.
EquivalentX-rayvoltage:
ThevoltageofaX-raytubewhichproducesaradiographmostnearlyequivalenttoagammaradiographtakenwithaparticulargamma-raysource.
Exposure:
Theprocesswherebyradiationisrecordedonanimagingsystem.
Exposurecalculator:
Adevice(forexampleasliderule)whichmaybeusedtodeterminetheexposuretimerequired.
Exposurechart:
Achartindicatingthetimeforradiographicexposuresfordifferentthicknessesofaspecifiedmaterialandforagivenqualityofabeamradiation,
Exposurelatitude:
Therangeofexposurescorrespondingtotheusefulopticaldensityrangeoftheemulsion.
Exposuretime:
Durationoftheprocessofexposingarecordingmediumtoradiation.
Filmbase:
Thesupportmaterialonwhichthephotosensitiveemulsioniscoated.
Filmgradient(G):
TheslopeofthecharacteristiccurveofafilmataspecifiedopticaldensityD.
Filmilluminator(viewingscreen:
(viewingscreen)Equipmentcontainingasourceoflightandatranslucentscreenusedforviewingradiographs.
Filmprocessing:
Theoperationsnecessarytotransformthelatentimageonthefilmintoapermanent,visibleimage,consistingnormallyofdeveloping,fixing,washinganddryingafilm.
Filmsystemspeed:
Aquantitativemeasureoftheresponseofafilmsystemtoradiation,energy,forspecificexposure.conditions.
Filter:
Uniformlayerofmaterial,u!
sualhigheratomicnumberthanthespectmen,placedbetween1hp.radiationsourceandthefilmorepurposeofPreferentiallyabsorbing:
:
.the-softerradiations.
Fixing:
Thechemicalremovalofsilverhalidesfromafilmemulsionafterdevelopment.
Flawsensitivity:
Theminimumflawsizedetectableunderspecifiedtestconditions.
Fluorescentintensifying,screen:
AscreenconsistingofacoatingofphosphorswhichfluoresceswhenexposedtoX-orgammaradiation.
Fluorometallicintensifyingscreen:
Ascreenconsistingofametallicfoil(usuallylead)coatedwithamaterialthatfluoresceswhenexposedtoX-orgammaradiation.
Fluoroscopy:
TheproductionofavisibleimageonafluorescentscreenbyX-raysandfordirectviewingofthescreen.
Focalspotsize:
ThedimensionacrossthefocalspotofanX-raytube,measu
- 配套讲稿:
如PPT文件的首页显示word图标,表示该PPT已包含配套word讲稿。双击word图标可打开word文档。
- 特殊限制:
部分文档作品中含有的国旗、国徽等图片,仅作为作品整体效果示例展示,禁止商用。设计者仅对作品中独创性部分享有著作权。
- 关 键 词:
- 射线 英语