学科分类
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331 个结果
  • 简介:Wedevelopatheoreticalmodelforpredictingtheultrasonicattenuationintheliquid-solidsystemcontainingmixedparticles.Theultrasonicattenuationcoefficientisobtainedbycountingthenumberofphononsthatreachthereceiver.UsingtheMonteCarlomethod(MCM),numericalsimulationswereperformedtopredicttheultrasonicattenuationswithnotonlyasingleparticletypebutalsomonodisperseandpolydispersemixedparticles.Thesimulationresultsforthesystemswithasingleparticletypewerecomparedwithvariousstandardmodels.Theresultsshowthattheyagreewellatrelativelylowparticlevolumeconcentrations(within10%).Forsystemswithmixedparticles,theparticlevolumeconcentrationwasfoundtoincreasetoaround10%,andthevariationoftheultrasonicattenuationagainstthemixingratioyieldsanonlineartrend.Moreover,theultrasonicattenuationissignificantlyaffectedbyparticleproperties.Thenumericalresultsalsoshowthatboththeparticletypeandparticlesizedistributionshouldbecarefullytakenintoaccountinthedispersionswithpolydispersemixedparticles,wheretheMCMcangiveamoredirectdescriptionofthephysicsofsoundpropagationcomparedwiththeconventionalmodels.

  • 标签: ULTRASOUND ULTRASONIC ATTENUATION Monte Carlo method
  • 简介:Theboilingbehavioroftheliquidnitrogen(LN2)underthetransienthighheatfluxurgentlyneedstoberesearchedsystematically.Inthispaper,thehighpowershortpulsedurationlaserwasusedtoheatthesaturatedLN2rapidly,andthehigh-speedphotographyaidedbythesparklightsystemwasemployedtotakeseriesofphotoswhichdisplayedtheprocessofLN2'sboilingbehaviorundersuchconditions.Also,aspecialtemperaturemeasuringsystemwasappliedtorecordthetemperaturevariationoftheheatingsurface.TheexperimentsindicatedthatanexplosiveboilinghappenedwithinLN2bythelaserheating,andaconventionalboilingfollowedupafterthenewly-definedchangeovertime.Byanalyzingthetemperaturevariationoftheheatingsurface,itisfoundthatthelatentheatreleasedbythecrackofthebubblesinthebubbleclusterinducedbytheexplosiveboilingisanimportantfactorthatgreatlyinfluencestheboilingheattransfermechanism.

  • 标签: 爆炸沸腾 脉冲激光加热 液态氮气 状态转换时间
  • 简介:Methodsfordeterminingnienelowmolecular-weightoragnicacidsinrootexudatesweredevelopedbyusingreversed-phasehighperformanceliquiedchromatographywithUV(ultraviolet)detectionat214nm.Themobilephasewas18mmolL^-1kH2PO4adjustedtopH2.25withphosporicacidndtheflowratewas0.3mLmin^-1,Theanalyticalcolumnwasareversed-phasesilicabasedC-18column(shim-packCLC-ODS).Therootexudateswerecollectedthroughsubmergingthewholerootsystemintoaerateddeionizedwaterfor2hours,Thefilteredexudatesolutionswereconcentratedtodrynessbyrotaryevaporationat40℃,dissolvedin10mLmobilephase.Thechromatoraphicconditionsoforganicaciddeterminationwereanalyzed.Theresultsshowedthattherewasahighselectivityandsensitivityintheorganicaciddeterminationbyreversed-phasehighperformanceliquidchromatography.Coefficientsofvariationfororganicacieddeterminationwerelowerthan10%exceptlacticacid.Therecoverieswereconsistentlybetween80.1%to108.3%.Detectionlimitswereapproximately0.05to4.5mgL^-1fororganicacidsexceptsuccinicacidwiththedetectionlimitof7.0mgL^-1.Phosphorusdeficiencymaycontributetothereleaseoforganicacidsinsoybeanrootexudatesespeciallymalic,lacticandcitricacids.

  • 标签: 高效液相色谱法 有机酸 大豆 根围 根部分泌液 测定
  • 简介:WepresentseveralcomparisonsofGEANT4simulationswithtestbeamdataandGEANT3simulationsfordifferentliquidargon(LAr)calorimetersoftheATLASdetector,Allrelevantpartsofthetestbeamsetup(scintilators,multiwireproportionalchambers,cryostatetc.)aredescribedinGEANT4aswellasinGEANT3.MuonandelectrondataatdifferentenergieshavebeencomparedwithMonteCarloprediction.

  • 标签: ATLAS实验 电磁量热器 液态氩量热器 探测束数据模拟
  • 简介:Thesolvent-freemechanochemicalreactionandtheliquid-phasereactionofC60withethyl2-diazopropionatepreparedinsituorpreformedfromalanineethylesterhydrochlorideandsodiumnitritehavebeeninvestigated.Methanofullerene1andfulleroids2and3fromthesereactionswereobtained,meanwhilethepyrazolineintermediatewasnotobserved.Fulleroids2and3canbeconvertedtomethanofullerene1inrefluxingtoluene.

  • 标签: 乙基2-二重氮丙酸盐 碳60 液相反应 溶剂化作用 作用机理 富勒烯
  • 简介:Inthispaper,thetotalsugarconcentration,proteinconcentration,lipidyieldandmorphologycharacteristicsofthealgaeresidueweredeterminedtoexplainthemechanismoflipidsextractionfromwetmicroalgaeScenedesmussp.byionicliquidassistedsubcriticalwater.Theresultsshowedsimilarvariationforthesugar,proteinandlipid.However,thetotalsugarwasmoresimilartolipidsyield,sotheresultsshowedthatthereactionbetweenionicliquidandcelluloseandhemicelluloseincellwallwasthemostimportantstepwhichdeterminedthelipidsextrationdirectly.Andthetotalsugarvariationmayberepresentingthelipidsyield.Forlaterlipidsextraction,wecandeterminethetotalsugarconcentrationtopredicttheextractionendproduct.

  • 标签: 油脂提取 离子液体 亚临界水 栅藻 微藻 蛋白质含量
  • 简介:简单、快速、精确的高效液体色析法(HPLC)技术结合了化合光(CL)察觉为肾上腺素(E),noradrenaline(NA)和多巴胺(DA)的同时的决心被开发。它在在发光氨和钾铁氰酸盐之间的CL反应上基于analyte改进效果。各种各样的参数的效果发光氨集中,pH价值和analytes(E,NA和DA)的色析法的行为上的活动阶段的部件例如钾铁氰酸盐集中,被调查。分离用0.01mol/L钾氢phthalate答案和甲醇的活动阶段在C18列上被执行(92:8,V/V)。在1愠?桰獹潩潬楧慣?潣摮瑩潩?眠楨档椠?的范围在最佳条件,E,NA和DA下面显示出好线性关系???鶍?????鐿?醭靠??颮題????鞪吗??

  • 标签: 高性能液体色谱法 化学发光 去甲肾上腺素 多巴胺 血液样本
  • 简介:Theenantiomersofthirty-nineO-ethylO-phenylN-isopropylphosphoroamidothioateshavebeenseparatedbyhighperformanceliquidchromatographyonaPirklemodelchiralstationaryphaseusingtenmobilephase.Chromatographicdataarepresentedfortheseparationoftheseorganicphosphorusenantiomersonthechiralphase.Theinfluencesofmolecularstructuresandcompositionsofmobilephaseshavebeendescribed.

  • 标签: HPLC phosphorus ENANTIOMER SEPARATION PESTICIDE ENANTIOMERS
  • 简介:密度功能的理论(DFT)被采用了调查电子struc-turgsEMM+(1-emyl-3-methylimidazolium+),CuCl_2~-,Cu2Cl3~-CuCl_2~-,EMIM+-Cu2Cl3-和EMIM+-CuCl_2~-,EMIM+-Cu2Cl3-对。完整,EMIM~+的优化和频率分析,CuCl2,Cu2Cl_3~-,八起始的EMIM+-CuCl_2~-,并且六起始,EMTM+-Cu2Cl_3~-几何学在6-31+G用Gaussian-94软件包裹被执行了(d,p)基础,为氢的集合水平,碳,氮,氯原子和Hay-Wadt为铜原子的有效核心潜力。EMIM+-CuCl_2~-的最低精力的电子结构,EMIM+-Cu2Cl_3~-pairs,单身地,EMIM+,CuCl_2~-,和Cu_2Cl_3~-比较地被学习了。计算结果证明最低精力的优化EMIM+-CuCl_2~-对conformer是到有距离的CuCl_2~-飞机的五戒指一半平行在3.5A附近,当最低精力的EMIM+-Cu2Cl_3~-对conformer是对有在终端氯原子和EMIM+.The的5戒指飞机之间的约3.0A的距离的Cu2Cl_3~-飞机垂直的EMIM+的五戒指一半时,在阳离子和阴离子之间的结合是静电的相互作用和C-H-Cl氢键被费用帮助增强。频率分析建议因为想象的频率的缺席,所有静止的点是最小的点。EMIM~+的笨重不对称现象引起的相互作用的低精力,和阳离子和阴离子的费用分散产生离子的液体EMTM+-CuCl_2~-,和EMTM+-Cu2Cl_3~-的低融化的点;在阳离子和阴离子之间的距离引起的.The相互酌能被单个点精力调查扫描。

  • 标签: 离子液体 密度函数理论 1-乙基-3甲基咪唑 氯铜酸盐
  • 简介:Acylationreactionofanthracenewithoxalylchlorideinthepresenceof[Emim]C1-A1C13ionicliquidhasbeeninvestigated.Pure1,2-aceanthryenedione,whichisusedasintermediateoffunctionalaromaticpolymermaterial,wasobtainedbyrecrystallingthereactionmixturewithaetherandwasdeterminedbyGC/MS,1HNMRandFTIRanalysis.Theinfluencesofvariousparameters,suchasthecontentsofAlCl3in[Emim]C1-A1C13,theamountofacylationagent,amountof[Emim]C1-A1C13,reactiontemperatureandreactiontimewereinvestigated.Theoptimumconditionswereasfollows:themolarfractionofA1C13inionicliquid[x(AlCl3)]being0.67,molarratioofionicliquidtoanthracenebeing2:1,molarratioofoxalylchloridetoanthracenebeing2:1,reactiontemperaturebeing40℃andreactiontimebeing6h.Underaboveconditions,theyieldandselectivityof1,2-aceanthrylenedionecanreach91.5%and98.3%respectively.Furthermore,[Emim]C1-A1C13ionicliquid,comparedwithmetalhalidessuchasAlCl3,wasfoundtocatalyzethereactionasanovelenvironmentalfriendlycatalystandsolventandcanbereused.

  • 标签: 芳香烃 功能性大分子 酰基甘油 催化作用
  • 简介:Objective:Impairedactivefluidtransportofalveolarepitheliummayinvolveinthepathogenesisandresolutionofalveolaredema.Thcobjectiveofthisstudywastoexplorethechangesinalveolarepithelialliquidclearanceduringlungedemafollowingacutelunginjuryinducedbyoleicacid.Methods:Forty-eightWistarratswererandomlydividedintosixgroups,I.e.,injured,amiloride,ouabain,amilorideplusouabainandterbutalinegroups.Twenty-fourhoursaftertheinductionofacutelunginjurybyintravenousoleicacid(0.25ml/kg),5%albuminsolutionwith1.5μCi125Ⅰ-labeledalbumin(5ml/kg)wasdeliveredintobothlungsviatrachea.Alveolarliquidclearance(ALC),extravascularlungwater(EVLW)contentandarterialbloodgasesweremeasuredonehourthereafter.Results:At24haftertheinfusionofoleicacid,theratsdevelopedpulmonaryedemaandseverehypoxemia,withEVLWincreasedby47.9%andALCdecreasedby49.2%.Additionofeither2×10-3Mamilorideor5×10-4MouabaintotheinstillationfurtherreducedALCandincreasedEVLW.ALCincreasedbyapproximately63.7%andEVLWdecreasedby46.9%withimprovedhypoxemiaintheTerbutaline(10-4M)group,comparedthoseininjuredrats.AsignificantnegativecorrelationwasfoundbetweentheincrementofEVLWandthereductionofALC.Onclusions:Activefluidtransportofalveolarepitheliummightplayaroleinthepathogenesisoflungedemainacutelunginjury.

  • 标签: 急性肺损伤 动物模型 牙槽上皮细胞 油酸 离子转运
  • 简介:Inthisstudywesystematicallyanalyzedtheelutionconditionoftrypticpeptidesandthecharacteristicsofidentifiedpeptidesinreversephaseliquidchromatographyandelectrospraytandemmassspectrometry(RPLC-MS/MS)analysis.Followingproteindigestionwithtrypsin,thepeptidemixturewasanalyzedbyon-lineRPLC-MS/MS.Bovineserumalbumin(BSA)wasusedtooptimizeacetonitrile(ACN)elutiongradientfortrypticpeptides,andCytochromeCwasusedtoretestthegradientandthesensitivityofLC-MS/MS.Thecharacteristicsofidentifiedpeptideswerealsoanalyzed.Inourexperiments,thesuitableACNgradientis5%to30%fortrypticpeptideelutionandthesensitivityofLC-MS/MSis50fmol.Analysisofthetrypticpeptidesdemonstratedthatlonger(morethan10aminoacids)andmulti-chargestate(+2,+3)peptidesarelikelytobeidentified,andthehydropathicityofthepeptidesmightnotberelatedtowhetheritismorelikelytobeidentifiedornot.Thenumberofidentifiedpeptidesforaproteinmightbeusedtoestimateitsloadingamountunderthesamesamplebackground.Moreover,inthisstudytheidentifiedpeptidespresentthreetypesofredundancy,namelyidentification,charge,andsequenceredundancy,whichmayrepresslowabundanceproteinidentification.

  • 标签: 胰蛋白酶肽鉴定 蛋白质组 反相液相色谱 静电离子阱质谱 系统分析
  • 简介:Inordertosolvethemagneto-hydrodyna-mics(MHD)problems,itisneccessarytocombineMaxwell'sequationswithfluidmechanicsequations.But,underthefirstorderapproximationthemasspointmotivationequationsandelectromagneticbasiclawsare

  • 标签: MHD 不稳定性 喷气流 流体力学 麦克斯韦方程
  • 简介:Inthispaper,theflowpatternsobservedinhorizontalCouette-Taylorflow(CTF)werecorrelatedusingdimensionlessnumbers.Theanalysisoftheresultsshowedthatthestructureoftheflowwasanoutcomeofinteractionbetweenfluidinertiarelatedtoaxialandrotationalflowsandgravitation.Therefore,theflowstructureswerecorrelatedusingaxialandangularReynoldsnumbers,andArchimedesnumberforthegivenvalueofgas-to-liquidflowratio.Finally,thecorrelationforthepredictionofthetransitiontotheflowregimeobservedathighrotationalspeedswasproposed.ThecomparisonwithexperimentscarriedoutintheverticalCTFfromtheliteratureshowedthatthiscorrelationcanalsobeusefulinthecaseofverticalflow.

  • 标签: 无量纲准则 泰勒 分类 流型 气液
  • 简介:AhighsensitivityD-shapedholedouble-claddingfibertemperaturesensorbasedonsurfaceplasmonresonance(SPR)isdesignedandinvestigatedbyafull-vectorfiniteelementmethod.WithintheD-shapedholedoublecladdingfiber,thehollowD-sectioniscoatedwithgoldfilmandtheninjectedinahighthermo-opticcoefficientliquidtorealizethehightemperaturesensitivityforthefiberSPRtemperaturesensor.ThenumericalsimulationresultsshowthatthepeakinglossoftheD-shapedholedouble-claddingfiberSPRishugelyinfluencedbythedistancebetweentheD-shapedholeandfibercoreandbythethicknessofthegoldfilm,butthetemperaturesensitivityisalmostinsensitivetotheaboveparameters.Whenthethermo-opticcoefficientis-2.8×10-4∕℃,thethicknessofthegoldfilmis47nm,andthedistancebetweentheD-shapedholeandfibercoreis5μm,thetemperaturesensitivityoftheD-shapedholefiberSPRsensorcanreachto-3.635nm∕℃.

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  • 简介:Directsimulationof3-DMHD(magnetohydrodynamics)flowsinliquidmetalfusionblanketwithflowchannelinsert(FCI)hasbeenconducted.Twokindsofpressureequilibriumslot(PES)inFCI,whichareusedtobalancethepressuredifferencebetweentheinsideandoutsideofFCI,areconsideredwithaslotinHartmannwalloraslotinsidewall,respectively.ThevelocityandpressuredistributionofFCImadeofSiC/SiC_farenumericallystudiedtoillustratethe3-DMHDfloweffects,whichclearlyshowthatt...

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  • 简介:Amain-chainliquidcrystallineionomer(MLCI)containingsulfonicgroupwassynthesizedbyaninterfacialcondensationreaction.TheMLCIwasblendedwithpolybutyleneterephthalate(PBT)andpolypropylene(PP).MLCIinteractedwithboththedispersed(PP)phaseandthematrix(PBT)phasetomodifytheinterfacialinteractionofPBTandPP.Differentialscanningcalorimetry(DSC),scanningelectronmicroscopy(SEM)andFTIRimagingsystemanalysisdemonstratedthesignificanceofinterfacialinteractioninthepolymerblends.MLCIbroughtaboutgoodadhesionattheinterfacial,whichreducedthedispersephasesizeandenabledafinePPphaseatmatrix.ThemechanicalpropertiesoftheternaryblendswereimprovedwhenaproperamountofMLCIwasadded.Thiswasattributedtoenhancedadhesionattheinterface,whichinvokedbettermechanicalpropertiesintheblends.

  • 标签: 界面相互作用 液晶离聚物 PBT 磺酸基 PP 共混改性