資源描述：
《硬x射線位相襯度成像的實驗分析》由會員上傳分享，免費在線閱讀，更多相關內(nèi)容在行業(yè)資料-天天文庫。
1、窒壁墨型查蘭堡主蘭竺笙苧一一——Theteststudyofhardx-rayofphasecontrastimagingAbstractBackgroundsandobjectiveSincethediscoveryofx。raysbyConradRontgenin1895，almostallthepracticalusesofradiographyforhumanimaginghavebeenbasedonX．rayabsorbfioncontrastandopticgeometric．Thisabsorbtioncontrastimagingutilizedthehighpene
2、trabilityofX—ray，whenitpassthroughanobjectalonedifferentpathswillbedifferentiallyabsorbedandtheintensitypattemoftheemergingbeamrecordsthedistributionofabsorbingmaterialswithinthesample．thismethedcangivethematerialsinnerinformationwhichotherscannotsupply．eventhrough，asthesofttissuewhichbasedonlig
3、htelementsbecausethesofttissueonlyhavelittleabsorbtionornoabsorbtionorhavelittlediffrentialinabsorbtionSOitonlyinvestigatedfewinformationwithinsofttissue．in1965，doctorBonse．Ufind，forlightelements，e．g．carbon，hydrogen，oxygen，nitrogen．，thecrosssectionofthephaseshiftis1000timeslargerthanthatofabsorb
4、tion，itmeansthesensitivityofthismethodisaboutathousandtimeslargerthantheabsorbtioncontrast，indicatingthepossibilityofobtainingequivalentinformationaboutanobject，withaconsiderablyreducedabsorbeddose．a(chǎn)scomparedwithabsorbtionimaging．thistechniqueshaveadvantagestoimagethe，internalstructureofthicksam
5、ple，atthesametimeitcallimprovetheresolutiongreatlyandreachseveralmicron．wimtheadventofsynchrotronradiationfacility,thisphasecontrastimagingtechniquesgointorealityandgainedhighattation．a(chǎn)tpresent，thistechniquesaboutphasecontrastimaginghaveimprovedgreatlyandphsecontrast—CTisavailable．inOLlrcountryi
6、tisinitial，inthisarticleweintroduceourtestthatperfomedinBeijingsynchrotronradiationfacility(BSRF)，severalbiologicalobjectwereusedinthistestandobtainedphasecontrastimaging．thequality&thisimagingwereanalysisedandcomparedwiththatabsorbtionimagingSOthattofindthedifferencebetweenthattwoimaging．Method
7、sweperformedsomeexperimentstoobtainphasecontrastimagingsand7安徽匿科大學碩士學位論文absorbtioncontrastimagingsofseveraldifferentbiologicalobjectsinBeijingsynchrotronradiationfacility(BSRF4WIA)．theobjectincludesmallaquariumgoldfish，phyma
