简介:Thestudyofnucleonresonanceisanimportanttopicinhadronphysics.Themostimportantwaytostudythenucleonresonancesisthecollisionofthephotonandnucleon.Uptonow,theknowledgeaboutthenucleonresonancesaround2GeVisstillscarce.Recently,theCLASCollaborationatJeffersonNationalAcceleratorFacilityreleasedtheirexclusivephotoproductioncrosssectionsfortheΛ(1520),Σ0(1385)andΛ(1405)forenergiesfromnearthresholduptoacenterofmassenergyWof2.85GeVwithlargerangeoftheKproductionangle[1].SincethethresholdforthephotoproductionofΛ(1520)isabout2.01GeV,thenewexperimentaldatawithhighprecisionreleasedbytheCLASCollaborationprovideanopportunitytostudythenucleonresonancesabove2GeV.
简介:LinuxbasednetworkedPCsclustersarereplacingboththeVMEnonuniformdirectmemoryaccesssystemsandSMPsharedmemorysystemsusedpreviouslyfortheonlineeventfilteringandreconstrucion.ToallowanoptimaluseofthedistributedresourcesofPCclustersanopensoftwareframeworkispresentlybeingdevelopedbasedonadataflowparadigmforeventprocessing.Thisframeworkallowsforthedistributionofthedataofphysicseventsandassociatedcalibrationdatatomultiplecomputersfrommultipleinputsourcesforprocessingandthesubsequentcollectionoftheprocessedeventsatmultipleoutputs.Thebasisofthesystemistheeventrepository,basicallyafirst-infirst-outeventstorewhichmaybereadandwritteninamannersimilartosequentialfileaccess.Eventsarestoredinandtransferredbetweenrepositoriesassuitablylargesequencestoenablehighthroughput.Multiplereaderscanreadsimultaneouslyfromasinglerepositorytoreceiveeventsequencesandmultiplewriterscaninserteventsequencestoarepository,Hencerepositoriesareusedforeventdistributionandcollection.Tosupportsynchronisationoftheeventfolowtherepositoryimplementsbaaiers.Abarriermustbewrittenbyallthewritersofarepositorybeforeanyreadercanreadthebarrier,Areadermustreadabarrierbeforeitmayreceivedatafrombehindit.Onlyafterallreadershavereadthebarrieristhebarrieremovedfromtherepository.Abarriermayalsohaveattacheddata,Inthiswaycalibrationdatacanbedistributedtoallproessuingunits.Therepositoriesareimplementedasmulti-threadedCORBAobjectsinC++andCORMAisusedforalldatatransfers,JobsetupscriptsarewritteninpythonandinteractivestatusandhistogramdisplayisprovidedbyaJavaprogram.JobsrununderthePBSbatchsystemprovidingshareduseofresourcesforonlinetriggering,offlinemassreporcessinganduseranalysisjobs.
简介:首先运用Phillips定理和Fattorini定理证明M/Mk,B/1排队模型概率瞬态解的存在唯一性,然后通过研究对应于M/Mk,B/1排队模型的主算子的共轭算子的豫解集得到该主算子的豫解集:在虚轴上除了零点外其它所有点都属于该主算子的豫解集.
简介:Thesymmetryenergywhichcharacterizestheisospindependenceoftheequationofstateofasymmetricnuclearmatter,playsacrucialroleinunderstandingavarietyofissuesinnuclearphysicsandastrophysics,suchasheavyioncollisions,exoticnuclei,stabilityofsuperheavynuclei,fusioncrosssections,thestructures,compositionandcoolingofneutronstars[1??5].Muchtheoreticalandexperimentalefforthasbeenmadetoconstrainthedensitydependenceofsymmetryenergy.Uptonow,wehavegotsomebasicknowledgeaboutthesymmetryenergyatlowdensities,whileathighdensitiesweevendonotknowitsvariationtendencyasafunctionofdensity.Theproblemremainsunsolvedduetothedifficultyofnucleon-nucleoninteractionsandmany-bodyproblems.
简介:InthispaperwestudythetheoreticalpropertiesofmultigridalgorithmfordiscretizationofthePoissonequationin2Dusingamortarelementmethodundertheassumptionthatthetriangulationsoneverysubdomainareuniform.WeprovetheconvergenceoftheW-cyclewithasufficientlylargenumberofsmoothingsteps.ThevariableV-cyclemultigridpreconditionerarealsoavailable.
简介:Pelletinjectionexperimentshavebeenwidelycarriedoutwithvarioustoroidalplasmas,peakeddensityprofileandimprovedconfinementarefrequentlyobserved,andsomeinterestingphenomenahavealsobeenfound.Oneofthemisthelong-livedm=1/n=1oscillationobservedonsoftX-rayemissionandotherdiagnostics(notablythemicrowaveinterferometersandtheECEsystems)afterpelletinjectioninJET,JT-60,
简介:Opticallyactive(R)-(+)-2,2’-bis(2-trifluoro-4-aminophenoxy)-1,1’-binaphthylwaspreparedfrom1,1’-bi-2-naphthol.Theopticallyactivearomaticpolyimidewasalsosuccessfullysynthesized.Thisnewpolymerhasgoodsolubility,thermalstabilityetc.Itsspecificrotationwasfoundtobe+174°,anditschiropticalpropertywasalsostudied.
简介:Novelsulfur-containingcompounds(3a–3c,4a–4c)wereobtainedinethanolwith1,3-diphenyl-2-propanoneasthestartingmaterial.Theadvantagesofthisprocedureweremildreactionconditions,simpleprotocol,andhighyields.ThestructuresoftheproductswerecharacterizedbyIR,1HNMR,MSandelementaryanalysis.Thecrystalofthenewcompound4abelongstomonoclinic,spacegroupC2witha=18.727(3),b=6.5179(9),c=13.7576(18),b=131.0610(10)°,V=1266.2(3)A3,Z=2,Dc=2.136g/cm3,μ=1.078mm-1,F(000)=843,R=0.0490andwR=0.1247for3211observedreflectionwithI>2δ(I).X-rayanalysisrevealsthatthemoleculeisnotsymmetrical,themolecularstructureisstabilizedbyweakp–pstackinginteractions,andnoclassicalhydrogenbondscanbeobserved.
简介:Usingbi-spinorfieldswewritethepseudo-scalarandbi-spinorfieldsthatarecharacterizedbythefieldfunctionsofcoordinatesofseveralparticles,namelymulti-particlefields.Byapplyingthequantizationproceduretothesemulti-particlefields,hadroniccreationandannihilationoperatorshavebeenobtained.
简介:Twoseriesofnovelcompoundsdesignedashybridsof1-arylnaphthalenelignanswithdihydroisoquinolinesorisoquinolinesweresynthesizedandevaluatedfortheircytotoxicitiesonhumantumorcelllines,suchasA549,Hela,PC-3andKB.SomeofthesyntheticcompoundsexhibitedtheirIC50valuesonselectedcelllinesatμmol/Lscale.
简介:Anovertphenotypeofaquaporin-1knockout(AQP1ko)miceisgrowthretardation,suggestingpossibledefectsinbonedevelopmentandmetabolism.Inthepresentstudy,weanalyzedthebonemineraldensity(BMD),bonecalciumandphosphoruscontents,andbonemetabolisminanAQP1komousemodel.TheBMDoffemursinAQP1komicewassignificantlylowerthanthatoflitter-matchedwildtypemiceasmeasuredbydualenergyX-rayabsorptiometry.Consistently,thecontentsofbonetotalcalciumandphosphoruswerealsosignificantlylowerinAQP1komice.ThereducedBMDcausedbyAQP1deficiencymainlyaffectmalemice.Bonemetabolicactivity,asindicatedby99mTc-MDPabsorptionmeasurements,wasremarkablyreducedinAQP1komice.TheseresultsprovidethefirstevidencethatAQP1playanimportantroleinbonestructureandmetabolism.