简介：BasedontheFenlon‘stheorytheparametriceffectsinfluidsduetothenonlinearinteractionofalowfrequencypumpingwaveandahighfrequencyprobingwaveareanalysed.TheexpressionsofpressureamplitudeofsumordifferencefrequencysidebandandthefromulaofnonlinearityparameterB/Aforlossymediumarederived.Theoreticalcalculationdemonstrated,thatthesidebandcomponentsincreaselinearlywithpumpsignal.Therefore,amethodfordeterminationofB/Aisprovidedandtheval-uesforseveralbiologicalfluidsandmixturesaremeasured.

简介：Thisworkbrieflysummarizedtherecentresearcheffortsmadeonthephaseheattransferprocessesinvolvingbiologicalaggregates,withparticularattentiononthecorrelationofaggregatestructureandstateofwaterwiththeprocessefficiency.Thephasechangeprocessesincludeboiling,drying,freezing,sintering,pyrolysis,andsupercriticalextraction,whiletheformerthreewerediscussedinsomedetail.

简介：Thefieldofmechanicsofbiologicalandbio-inspiredmaterialsunderwentanexcitingdevelopmentoverthepastseveralyears,whichmadeitstandatthecuttingedgeofbothengineeringmechanicsandbiomechanics.Asanintriguinginterdisciplinaryresearchfield,itaimsatelucidatingthefundamentalprinciplesinnature'sdesignofstrong,multi-functionalandsmartMaterialsbyfocusingontheassembly,deformation,stabilityandfailureofthematerials.Theseprinciplesshouldhavewideapplicationsinnotonlymaterialsciencesandmechanicalengineeringbutalsobiomedicalengineering.Forinstance,theknowledgeinMechanicalprinciplesofbiologicalmaterialsisveryhelpfulforaddressingsomemajorchallengesinmaterialsciencesandengineering.Theyalsohavethepotentialtoprovidequantitativeunderstandingabouthowforcesanddeformationaffecthumanbeing'shealth,diseasesandtreatmentattissue,cellularandmolecularlevels.

简介：Manybiologicalmaterials,suchaswoodandbone,possesshelicoidmicrostructuresatmicroscale,whichcanserveasreinforcingelementstotransferstressbetweencracksurfacesandimprovethefracturetoughnessoftheircomposites.Failureprocesses,suchasfiber/matrixinterfacedebondingandslidingassociatedwithpull-outofhelicalfibers,areresponsiblemainlyforthehighenergydissipationneededforthefracturetoughnessenhancement.Herewepresentsystemicanalysesofthepull-outbehaviorofahelicalfiberfromanelasticmatrixviathefiniteelementmethod(FEM)simulation,withimplicationsregardingtheunderlyingtougheningmechanismofhelicoidmicrostructures.Wefindthat,throughtheiruniformcurvatureandtorsion,helicalfiberscanprovidehighpull-outforceandlargeinterfaceareas,resultinginhighenergydissipationthataccounts,toalargeextent,forthehightoughnessofbiologicalmaterials.Thehelicityoffibershapeintermsofthehelicalanglehassignificanteffectsontheforce-displacementrelationshipsaswellasthecorrespondingenergydissipationduringfiberpull-out.

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简介：Systemsofphotosyntheticreactioncentreshavebeenmodelledasheatengines,whileithasalsobeenreportedthattheefficiencyandpowerofsuchheatenginescanbeenhancedbyquantuminterference—atraitthathasattractedmuchinterest.Wecomparetwodefinitionsoftheworkofsuchaphotosyntheticheatengine,i.e.definitionAusedbyWeimeretal.andBbyDorfmanetal.Wealsointroduceacoherentinteractionbetweendonorandacceptor(CIDA)todemonstrateareversibleenergytransport.Weshowthatthesetwodefinitionsofworkcanimpartcontradictoryresults,thatis,CIDAenhancesthepowerandefficiencyofthephotosyntheticheatenginewithdefinitionBbutnotwithA.Additionally,wefindthatbothreversibleandirreversibleexcitation-energytransportcanbedescribedwithdefinitionA,butdefinitionBcanonlymodelirreversibletransport.Asaresult,weconcludethatdefinitionAismoresuitableforphotosyntheticsystemsthandefinitionB.

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简介：Biologicalmaterialssuchasbone,tooth,andnacreareload-bearingnanocompositescomposedofmineralandprotein.Sincethemineralcrystalsoftenhaveslendergeometry,thenanocompositesaresusceptibletobuckleunderthecompressiveload.Inthispaper,weanalyzethelocalbucklingbehaviorsofthenanocompositestructureofthebiologicalmaterialsusingabeam-springmodelbywhichwecanconsiderplentyofmineralcrystalsandtheirinteractioninouranalysiscomparedwithexistingstudies.Weshowthatthereisatransitionofthebucklingbehaviorsfromalocalbucklingmodetoaglobalonewhenwecontinuouslyincreasetheaspectratioofmineral,leadingtoanincreaseofthebucklingstrengthwhichlevelsofftothestrengthofthecompositesreinforcedwithcontinuouscrystals.Wefindthatthecontactconditionatthemineraltipshasastrikingeffectonthelocalbucklingmodeatsmallaspectratio,buttheeffectdiminisheswhentheaspectratioislarge.Ouranalysesalsoshowthatthestaggeredarrangementofmineralplaysacentralroleinthestabilityofthebiologicalnanocomposites.

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简介：Aseriesoffuroxan-basednitricoxide-releasingmatrinederivatives(10a-f)weresynthesized.Thebiologicalevaluationshowedthatcompounds10a,10b,10eand10fhadstrongercytotoxicactivitiesthan5-fluorouracilagainsthumanhepatomacells(HepG2)invitro.

简介：Fromthepress-residueofthefreshroottuberofTrichosantheskirilowiiMaxim(Cu-curbitaceae),anewribosome-inactivatingprotein(RIP),trichobitacin,wasisolated.IthastheactivityofRNAN-glycosidaseandcaninhibitthegrowthofhumanplacentaltrophoblasticcells.Itsmolecularweightis27,228Da(ES-MS)andpI9.6.ItisasinglechainbasicRIP.Itsaminoacidcompositionwasdetermined.ItisanewRIP.Itconsistsof0.7~0.9%galactoseandmaybeaglycoprotein.ItsA’-andC-terminalaminoacidisAspandAla,respectively.ItsN-terminalpreliminaryaminoacidsequencehasbeendetermined.

简介：高光的放大三维的成像系统用谁的一台眼的显微镜被建议眼睛(接眼镜)被保留，传播模式的结构没被破坏。元素的图象数组通过微透镜数组被捕获。由于前面传播传播元素，每个微透镜看到景色的一个稍微不同的空间观点，和一幅不同独立图象在每条微透镜隧道被形成。每条微透镜隧道被一个Fourier透镜想象并且由电荷耦合器件捕获了。在x或y翻译阶段的设计不提供视差。与常规不可分的成像相比微目标，光放大在显著地提高的建议系统罐头微目标。图象深度的改进的原则详细被解释，试验性的结果被介绍。

简介：Thetwocompounds,2,2-dimethyl-4-S-(N,N-dimethyldithiocarbamato)-5-(1,2,4-triazol-l-yl)-propione(1)and2,2-dimethyl-4-S-(N,N-diethyldithiocarbamato)-5-(1,2,4-triazol-1-yl)-3-propione(2),werepreparedbyreactingN,N-dialkyldithiocarbamatesodiumwith2,2-dimethyl-4-bromo-5-(1,2,4-triazol-1-yl)-propione.Theirstructureswereidentifiedbyelementalanalysis,IRand^1HNMRspectroscopy.Thestructureof1hasbeendeterminedbyX-raysinglecrystalstructureanalysis.ItcrystallizesinmonoclinicsystemwithspacegroupP21/c,a=1.2315(3)nm,b=1.2057(2)nm,c=1.2532(3)nm,β=118.55(3)°,Z=4,V=1.6345(6)nm^3,Dc=1.221g/cm^3,μ=0.324mm^-1,F(000)=640,finalR1=0.0449.ThereisobviouspotentiallyweakC—H...Nintermolecularinteractioninthecrystal,whichstabilizesthecrystalstructure.Theresultofthebiologicaltestshowedthatthetwocompoundshavefungistasisandplantgrowthregulatingactivities.

简介：TwoN-dichloroacetyloxazolidinesweresynthesizedwithasimple,mildandconvenientmethod.AllthecompoundswerecharacterizedbyIR,^1HNMRandelementalanalysis.Thepreliminarybiologicaltestshowedthatthecompoundsprotectedmaizeagainstinjurybysomeherbicidestosomeextent.

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简介：Aseriesofethyl6-alkoxy-7-phenyl-4-hydroxy-3-quinolinecarboxylatesweredesignedandsynthesized.Theirstructureswereconfirmedby~1HNMR,~(13)CNMR,IRandHRMS.ThebiologicalactivitieswereprimarilyevaluatedagainstEimeriatenellaaccordingtoAnticoccidialIndex(ACI)methodinvivo.Theresultsshowedthatcompounds5e,5fand5iexhibitedanticoccidialactivitiesagainstE.tenellaat27mgkg~(-1).

简介：Shortpeptidesbasedonthetripeptides,Leu-Arg-ProandLeu-Lys-Pro,weresynthesizedbymicrowaveassistedsolid-phasesynthesismethod,inordertomakeasearchforpotentialinhibitorsforangiotensinI-convertingenzyme(ACE)withminimumsideeffectsinthetreatmentofhypertension.OnepeptidewiththesequenceLeu-Arg-Pro-Phe-PheshowsthestrongestinhibitiontowardsACEwithanIC50valueof0.26μmol/Linvitro.Thestudyofstructure-activityrelationshipshowsthattheintroductionofabulkygroupintotheN-terminalofthisseriesofinhibitorsmayenlargesterichindrance,resultinginthepoorinhibitoryactivitytowardsACE.TheinhibitoryactivitydecreasedinturnwhenL-Pro,D-ProorAc6cwasattheC-terminalrespectively.ThebindinginteractionbetweeneachoftheseinhibitorsandtesticularACE(tACE)wasperformedbymoleculardocking.TheresultssuggestthatLeu-Arg-Pro-Phe-PhemainlyoccupiedtheS1subsiteoftACE,andmadecontactwithtACEviasevenH-bonds.ItappearedthatthesiteonthepeptidethatboundwithtACEwasinfluencedbytheconfigurationoftheaminoacid,LorD-form,attheC-terminalofthepeptide.