简介：IntroductionAlthoughtheapplicationofmicrowavetechniquehasbeenreportedasanewtypeofenergysourcechemically,itisonlyinrecentyearsthatthistechniquehasbeenusedastheenergysourcefororganicsynthesis.In1986,R.Gedye,etal.,publishedthereportofthebenzoatesynthesisfromtherespectivereactionsbetweenbenzenecarboxylicacidandmethanol,propanolorbutanolundermicrowaveheatingandthecatalysisofH2SO4.
简介：Severalaspectsoftheapplicationofsilverelectrodetotheelectrochemicalstudiesofhemoglobinhavebeendiscussedinthispaper.Thesilverelectrodecouldnotonlybeuseddirectlyastheelectrodefortheelectrochemicalstudiesofhemoglobin,butalsoreactwithphenothiazineandbenzimidazoletogivestableandusefulmediator-coatedelectrodes.Inaddition,thesilverelectrodecouldhelpsodiumdodecylsulfatetogivefullplaytoitspromotingeffectontheprotein.
简介：Carbonnanotubesusedforconstructingbiosensorwasdescribedforthefirsttime.Single-wallcarbonnanotubes(SWNTs)functionalizedwithcarboxylicacidgroupswereusedtoimmobilizeglucoseoxidaseformingaglucosebiosensor.Thebiosensorresponsecanbedeterminedbyamperometricmethodatalowappliedpotential(0.40V).
简介：INthepreviouspapersoftheauthor’s,theelementaryreactionoperatorconcerningpointgroupwasdiscussed.Inthispaper,morecomplexreactionoperatorswillbeanalysed.Byusingtheskillinreactionoperator,theelectrocyclicandcy-cloadditionreactionsareillustrated.
简介：——PhaseBehavioroftheAqueousSolutionofPoly(vinylmethylether)SensitivetoTemperatureandtheModificationoftheBehaviorbyUsingPoly(acrylicacid)Thephasebehavioroftheaqueoussolutionofpoly(vinylmethylether)(PVME)sensitivetotemperatureandthemodificationofthebehaviorbyusingpoly(acrylicacid)(PAA)havebeenstudiedbyultrasonicattenuationmeasurementsandfluorescenceprobetechniques.IthasbeenobservedthatPVMEsolutionistransparentatroomtemperatureandbecomesturbiduponheating.Thesolutionturnsclearagainassoonasthetemperatureisdecreasedtoroomtemperature.Theheatingandcoolingprocesscanberepeatedformanytimes.Thephasebehaviorofthesolutionsensitivetotemperatureisattributedtotheconformationalchangesofthepolymer.PVMEmayadoptanopencoilconformationatroomtemperature.Withthisconformation,thepolymeriswellmisciblewiththesolvent,water,andtherebythesystemisarealsolution.Thepolymermayadoptacompactcoilconformationwhenthetemperatureishigherthanaspecificvalue,whichiscalledtheLCST(thelowercriticalsolutiontemperature)ofPVME.Inthiscase,thepolymertanglestoeachotherandformsvariousaggregates,whichcanscatterincidentlightandultrasonicwavesgreatly,resultinginthephaseseparation.IntroductionofPAAdecreasesthetemperaturesensitivityofthephasebehaviorofthepolymer.ThenatureoftheinhibitionisattributedtothecomplexationofPAAwithPVMEandthestronghydrophilicityofPAA.Resultsfromfluorescenceprobestudiesareinaccordancewiththosefromultrasonicattenuationmeasurements,indicatingagainthattheultrasonicattenuationmethodcanbesuccessfullyusedforthequalitativestudiesofpolymerconformationsandcomplexationbetweenpolymers.
简介：钴hexacyanoferrate(CoHCF)nanoparticle(尺寸ca。60nm)化学上修改的电极(CME)被制作，在这nanosizedCoHCFCME的血红素(Hb)的电气化学的行为被学习。与一个赤裸的玻璃质的碳电极(GCE)和以一种传统的方式的一般CoHCFCMEelectrodeposited比较，现在的nanosizedCoHCFCME高效地与相对高的敏感，稳定性，和longlife为Hb执行了electrocatalytic减小。与液体层析(LC)结合了，nanosizedCoHCFCME在确定的流动注射被用作Hb的电气化学的察觉者分析电气化学的决心(FIA-ECD)系统。山峰水流是在从2.5楳?景映牯業?捡摩映潲?慣'R湯搠潩楸敤愠摮栠摹潲敧?獵湩?的范围的集中的线性功能?楳楬慣椠浭扯汩穩摥爠瑵敨楮浵挠瑡污獹?獡瀠敲畣獲牯栠獡戠敥?瑳摵敩?湩搠晩敦敲瑮爠慥瑣潩?潣摮瑩潩獮?桔?敲?瑬?敲敶污摥琠慨?桴?佔?琨牵?癯牥映敲畱湥祣?景?佃?愠档敩敶????栠?漠?浩潭楢楬敺?畲桴湥畩?慣慴祬瑳渠慥?桴?牣瑩捩污瀠敲獳牵?潰湩?景??眠瑩??瀠敲獳牵?景???慐?敲捡楴湯琠浥数慲畴敲漠吗？？？？
简介：TakingthetransportoftotalphosphorpollutantsintheBeijingMiyunreservoirforexample,wehaveobtainedthreedimensionaldistributingregularityoftotalphosphorpollutantsbythecalculationofthelinearinterpolationvalueofeachpointbetweenhorizontallayers.Thecredibilityanalysisinallusiontothismethodwascarriedoutandtheprogrammingschemeforrealizingthismethodwassetforth.
简介：Theinteractionofbromothymolblue(BB)withhumanserumalbumin(HSA)wasstudiedbyelectrochemicaltechniquesandasensitivemethodforproteinsassaywasdeveloped.WhenBBinteractedwithHSA,thevoltammetricpeakcurrentvalueofBBdecreasedlinearlywiththeconcentrationofHSAinarangeof1.0―40.0mg/L,andthepeakpotentialshiftednegatively.Basedontheresults,asensitiveassaymethodforproteins,suchasHSA,bovineserumalbumin(BSA),andeggalbuminetc.wasestablished.ThismethodwasfurtherappliedtodeterminingtheHSAinhealthyhumanbloodsamples,andtheresultsarenotsignificantlydifferentfromthoseobtainedbytheclassicCoomassieBrilliantBlueG-250spectrophotometicmethod.Thedetectingconditionsofthismethodwereoptimizedandtheinteractionmechanismwasdiscussed.Theresultsshowthattheelectrochemicalparameters(formalpotentialE0,standardrateconstantoftheelectrodereactionks,parameterofkineticnα)ofBBhavenoobviouschangesbeforeandaftertheinteraction,whichindicatethatBBcaninteractwithHSA,forminganelectrochemicalnon-activecomplex.Theequilibriumconstant(βs)andthebindingratio(m)forthiscomplexwerecalculated.Themis4andβsis1.41×1019.Thismethodisfast,simple,highlysensitive,andhasgoodselectivity,whichcanbeusedinclinicalmeasurements.
简介：Arapidandeffectivemethod,solidphaseextractioncoupledwithhighperformanceliquidchromatography(SPE-HPLC),wasappliedtotheseparationandanalysisofginsenosides.WatersOASISHLBwasusedforconcentratingandpurifyingsamplesandAlltimaC_(18)(53mm×7mm,3μm)chromatographycolumnwasusedforseparatingginsenosideRg_1,Re,Rb_1,Rc,Rb_2andRd.Theseginsenosideswereanalyzedwithin20mininourgradientelutionprocessandtheequilibriumtimeofthechromatographycolumncostonly5min.Moreover,therewasnoobviousbaselinedriftinourexperiment.Thismethodwasusedtoanalyzethecontentsofginsenosidesindifferentginsengproductsforqualitycontrol.Fourginsengproductswerestudied,includingtwokindsofcapsules,onekindoftabletandonekindofinjection.Theresultsshowthatthemethoddevelopedinthispaperhadgoodaccuracy,linearityandprecision.Therefore,thismethodcouldbeappliedinqualitycontrolofginsengproducts.
简介：Thekineticstudyofin-situcopolymerizationofanilinewitho-andp-methylanilinebyammoniumpersulfate(APS)hasbeencardedout.UV-visspectroscopicmethodwasusedtoinvestigatethecourseofcopolymerization.StructuralcharacterizationwasstudiedbyFT-IRspectralanalysis.Theelectronicspectraofthecopolymerspoly(aniline-co-p-toluidine)andpoly(aniline-co-o-toluidine)showblueshift.Theshifthasbeenobservedinthebandscorrespondingtoπ→π~*transitionaswellasintheexcitontransition.Theincreaseinabsorbancerecordedduringthereactionfordifferentconcentrationofaniline,o-andp-toluidineatvariousintervalsoftimeofpolymerizationreactionindicatesagrowthinthepolymerformation.Theresultingfirst-orderrateconstantwasusedtocalculatetherateofcopolymerformationusingtherateequation-d[A]/dt=kc~n.
简介：
简介：Thedye-dopedsilicananoparticlescanbeusedasnanobiosensorsthatareabletorecognizeanddetectspecificDNAsequence.Inthispaper,sphericalnanosizedluminol/SiO2compositeparticleshavebeensynthesizedwithreversemicellsviahydrolysisoftetraethylorthosilicate(TEOS)inthemicroemulsion.ThenanoparticlesweremodifiedwithchitosanandusedtolabelDNA,formingtheDNAprobewhichwasusedtohybridizewithtargetDNAimmobilizedonaPPymodifiedPtelectrode.Thehybridizationeventswereevaluatedbyelectrogeneratedchemiluminescence(ECL)measurementsandonlythecomplementarysequencecouldformadouble-strandedDNA(dsDNA)withDNAprobeandgivestrongECLsignals.Athreebasemismatchsequenceandanon-complementarysequencehadalmostnegligibleresponses.Duetothelargenumberofluminolmoleculesinsidesilicananoparticles,theassayallowsdetectionatlevelsaslowas2.0×10^-12mol/LofthetargetDNA.TheintensityofECLwaslinearlyrelatedtotheconcentrationofthecomplementarysequenceintherangeof5.0×10^-12—1.0×10^-9mol/L.
简介：ChiralRu-BsDPEN,(1R,2R)-N-p-benzenesulfonyl-1,2-diphenylethylenediamine,catalysthasbeenimmobilizedonamesoporousmolecularsieveofMCM-41typesuccessfully.Ahybridmesoporousmolecularsievewassynthesizedusingaprecursorbearingbenzenegroup,whichinorganosilicaweresulfonylatedandreactedwith(1R,2R)-l,2-diphenylethylenediamineand[RuC1E(p-cymene)]2successivelytoaffordimmobilizedcatalyst.TheBrunauer-Emmett-Teller(BET)surfaceareaandBarrett-Joyner-Halenda(BJH)poresizedecreasedafterimmobilizationofcatalystontothemesoporousmaterial.Enantioselectivetransferhydrogenationofketonescatalyzedbyimmobilizedcatalystshowedthehighestyieldof22.36%ande.e.valueof31.47%byusingacetophenoneassubstratewhenreactiontimewas48and16hrespectively.
简介：Citricacidisanimportantadditiveinfoods,cosmetics,medicineandsoon,butitdischargesabout10tonoffactoryeffluentwhen1tonofcitricacidisproduced.TheCODofthefactoryeffluentisnear20000mg/L.Thetreatmentofcitricacidfactoryeffluentisaseriousprobleminenvironmentalchemistry.Itisfoundthatmolecularsievesupportmetalcomplexeshavehighcatalyticactivityinaerobicoxidationofalkene[1,2].Inthispaper,akindofmolecularsievecatalystwasprepared.Thecatalystwasusedforthetreatmentofcitricacidfactoryeffluentbymethodofcatalyticoxygenoxidation.
简介：Theoreticalconsiderationwasproposedforthefrequencyresponseofaseriespiezoelectricsensortothepropertiesofliquidandverifiedexperimentally.Thiskindofsensorhassensitiveandselectivefrequencyresponsetothepermittivityandspecificconductivityofsolutionwithexcellentstability,andwasappliedtothedeterminationofmicro-contentofwaterinorganicsolvents.Thedetectionlimitis0.01g/Lindioxane.
简介：AstatisticalthermodynamictheoryoflinearproteinsolutionswasproposedwiththeaidofalatticemodelandappliedtotypeⅠantifreezeprotein(AFPI)solutions.ThenumericalresultsforseveralAFPIsolutionsshowthattheGibbsfunctionofthesolutionhasaminimumatacertainproteinconcentration,buttheproteinchemicalpotentialincreaseswithincreasingtheconcentration.TheinfluencesoftemperatureandproteinchainlengthontheAFPIchemicalpotentialwerealsodiscussed.Theevaluationforthecolligativedepressionofthefreezingpointconfirmsthattheantifreezeactionshouldberecognizedasnon-colligative.Thetheoreticaldeductionfortheconcentrationdependenceofthethermalhysteresisactivitycoincidesqualitativelywiththepreviousexperimentalandtheoreticalresults.
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