简介:在蜗的听觉的信号transduction是包含非线性的扩大和自发的otoacoustic排出物的一个活跃过程。当振荡器关门到Hopf分叉,信号transduction包含由全球性联合的毛细胞组成的单个子单元,它能被建模。联合可以向同步导致转变,它接着导致强壮的非线性的回答。在这里学习的模型,子单元的同步转变是不连续的(炸药)当外部刺激不在时。我们显示出那,面对外部刺激,为acoupling,力量稍微比导致爆炸同步的批评价值降低,子单元的反应有更好的频率选择和更大的signal-to-noise比率。从子单元自己一起被联合的生理的观察,我们进一步建议完全的蜗的一个模型,为机关能检测的频率的整体的财务。
简介:Soundisoneoftheinformationcarriersoftenusedinanimalcommunication.Soundproducedbyani-malsisusefulnotonlyinintraspecificcommunication,butalsoinalarmoraggression.Threebasicproblemsinhearingshouldberesolvedi.e.frequencyselectivity,patternrecognitionandsounddirection.Withintracellularrecordingandsinglecellstainingtechniques,frequencyselectivityofprimaryauditoryneuronsinthebushcrickethasbeenstudied.Eachneuronhasitscharacteristicbestfrequency(BF)andtuningcurveinresponsetosound.Thecentralprojectionsoftheiraxonsintheprothoracicganglionareunilateral,non-transsegmentalandofsomecorrespondingrelationtotheirBFs.Neuralmechanismsforfrequencyanalysisinspecies-specificsongrecognitionofthebushcricketarediscussed.
简介:有bis-thiourea的4functionalized武装的新奇器官无机的nanohybrided受体然后集合在金nanoparticles上被综合。preorganized系统为dicarboxylates察觉到的spectrophotometric拥有phenylthiourea单位,特别malonate,基于在金nanoparticles(GNP)的表面电浆子吸收的变化。吸收度乐队的紧张与dicarboxylates增加的集中逐渐地增加。但是在电浆子乐队的如此的一个离子选择的变化没在测试由mono-thiourea-modifiedGNP执行了的控制被观察,受体第3a免费receptor2。当它从协会常数被显示出,源于量的滴定,受体4能有选择地认出更短的碳链的dicarboxylate阴离子,并且有最高的亲密关系到malonate。为受体4的阴离子的相互作用性质被1HNMR和紫外力的分光镜的方法评估。
简介:Overthepastfewdecades,extremechangeshaveoccurredinthecharactersofexploitedfishpopulations.Themajorityofthesechangeshaveaffectedthegrowthtraitsoffishlifehistory,whichincludeasmallersize-at-age,anearlierage-at-maturationandamongothers.Currently,thecausesoftheselifehistorytraitschangesstillrequiresystematicanalysesandempiricalstudies.Theexplanationsthathavebeencitedaremerelyexpressedintermsoffishphenotypicadaptation.Ithasbeenclaimedthattheoriginaltraitsoffishcanberecoveredoncetheintensityofexploitationofthefishiscontrolled.Sustainedenvironmentalandfishingpressurewillchangethelifehistorytraitsofmostfishspecies,sothefishindividual’straitsarestillinsmallsize-at-ageandatearlierage-at-maturationinexploitedfishpopulations.Inthispaper,weexpressedourviewofpointsthatfishinggearhasimposedselectivityonfishpopulationsandindividualsasvariousotherenvironmentalfactorshavedoneandsuchchangesareunrecoverable.Accordingtotheexistingtendofexploitedfishindividual’slifehistorytraits,wesuggestedfurtherresearchesinthisfieldandprovidedbettermethodsoffisherymanagementandtherebyfisheryresourcesprotectionthanthoseavailableearly.
简介:制作合成马赛克膜的一个新奇方法被涂层根据界面的聚合(IP)学习薄选择的层到多微孔的空纤维的膜的表面上,在哪个,2,5-diaminobenzene酸性硫酸基的酸被用作IP反应的一单体,并且trimesoyl氯化物(TMCl)和4-(chloromethyl)的混合物benzoyl氯化物作为另外的单体。通过与否定地为充电的组一起的薄选择的层能是的IP反应,第一在polyethersulfone(足)上形成了支持膜。然后,trimethylamine答案被介绍通过quaternization反应修改IP层。因此,否定地两个都包含的这合成的膜的选择的层收费了并且断然为组充电了执行马赛克功能。合成马赛克膜的描述用不同的无机的盐和染料通过浸透实验被执行。试验性的结果证明膜能渗入一价、二原子价的无机的盐,但是拒绝更大的器官的分子。如此的马赛克膜为从水溶性的organics的盐的分离是潜在地有用的,特别在染料和纺织品工业。
简介:BimetallicFe-Mnnanocatalystssupportedoncarbonnanotubes(CNTs)werepreparedusingmicroemulsiontechniquewithwater-to-surfactantratiosof0.4-1.6.ThenanocatalystswereextensivelycharacterizedbydifferentmethodsandtheiractivityandselectivityinFischer-Tropschsynthesis(FTS)havebeenassessedinafixed-bedmicroreactor.Thephysicochemicalpropertiesandperformanceofthenanocatalystswerecomparedwiththecatalystpreparedbyimpregnationmethod.Verynarrowparticlesizedistributionhasbeenproducedbythemicroemulsiontechniqueatrelativelyhighloadingofactivemetal.TEMimagesshowedthatsmallmetalnanoparticlesintherangeof3–7nmwerenotonlyconfinedinsidetheCNTsbutalsolocatedontheoutersurfaceoftheCNTs.Usingmicroemulsiontechniquewithwatertosurfactantratioof0.4decreasedtheaverageironparticlesizesto5.1nm.Thereductionpercentageanddispersionpercentagewerealmostdoubled.Activityandselectivitywerefoundtobedependentonthecatalystpreparationmethodandaverageironparticlesize.COconversionandFTSrateincreasedfrom49.1%to71.0%and0.144to0.289gHC/(gcath),respectively.WhiletheWGSratedecreasedfrom0.097to0.056gCO2/(gcath).C5+liquidhydrocarbonsselectivitydecreasedslightlyandolefinsselectivityalmostdoubled.
简介:Cu-Fecompositeoxideswerepreparedbyco-precipitationmethodandtestedforhigheralcoholsynthesisfromsyngas.TheselectivitytoC2+OHandC6+OHinalcoholdistributionwasveryhighwhilethemethaneproductfractioninhydrocarbondistributionwasratherlow,demonstratingapromisingpotentialinhigheralcoholssynthesisfromsyngas.ThedistributionofalcoholsandhydrocarbonsapproximatelyobeyedAnderson-Schulz-Florydistributionwithsimilarchaingrowthprobability,indicatingalcoholsandhydrocarbonsderivedfromthesameintermediates.TheeffectsofCu/Femolarratio,reactiontemperatureandgashourlyspacevelocity(GHSV)oncatalyticperformancewerestudiedindetail.ThesamplewithaCu/Femolarratioof10/1exhibitedthebestcatalyticperformance.Higherreactiontemperatureacceleratedwater-gas-shiftreactionandledtolowertotalalcoholsselectivity.GHSVshowedgreateffectoncatalyticperformanceandhigherGHSVincreasedthetotalalcoholselectivity,indicatingthereexistedvisibledehydrationreactionofalcoholintohydrocarbon.
简介:Variousmesoporouschromiaaluminacatalystswerepreparedbyfivedifferentmethodsbasedonametal-organicframeworkMIL-101andtheircatalyticperformancesoverisobutanedehydrogenationwereinvestigated.ThehighlydispersedchromiumspecieswereproducedoncatalystKCrAl-I1withlargestspecificsurfaceareaof198m2g-1preparedwithaluminiumisopropoxide(Al(i-OC3H7)3)byultrasonicimpregnationmethod.However,thecatalystKCrAl-I2synthesizedbystirringimpregnationpossessedcrystallineα-Cr2O3phase,whichwaspoorlydispersed.TwotypesofCr-richandAl-richCrxAl2-xO3solidsolutions,designatedasCrAl-IandCrAl-IIphase,wereformedoverthecatalystsKCrAl-I3(preparedbyAl(i-OC3H7)3withnitricacidregulation),KCrAl-C4(preparedbyaluminiumchloridehexahydrate)andKCrAl-N5(preparedbyaluminiumnitratenonahydrate).CatalyticevaluationresultsrevealedthatKCrAl-I1exhibitedthehighisobutaneconversionduetoitshighlydispersedchromiumspecies.However,KCrAl-I3,KCrAl-C4andKCrAl-N5showedthehigherisobuteneselectivity(95.2%-96.4%)onaccountoftheformationofchromiaaluminasolidsolutionsinthecatalysts.Moreover,thesolidsolutionoverthechromiaaluminacatalystscouldgreatlysuppressthecokeformation.
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简介:在在甲醇的9-vinyladenine和嘧啶库胸腺嘧啶之间的有约束力的机制与紫外可见的spectrophotometric方法被学习。把学习基于这,用象一个模板分子的胸腺嘧啶,是的9-vinyladenine是的新奇功能的单体和diethylene乙二醇dimethacrylate新cross-linker,特定的diethylene乙二醇基于dimethacrylate的分子地印的聚合的膜在纤维素支持上被准备。然后,结果地聚合的膜形态学与扫描电子显微镜学被设想,它的permselectivity作为底层用胸腺嘧啶,uracil,cytosine,腺嘌和guanine被检验。这结果证明印与diethylene乙二醇dimethacrylate准备的聚合的膜比另外的nucleic酸底为模板分子胸腺嘧啶和它的最佳的模拟uracil展出了更高的运输能力。膜也比作为cross-linker与乙烯乙二醇dimethacrylate做的印的膜呈现了更高的permselectivity。包括五nucleic酸的混合物什么时候基于胸腺嘧啶,uracil,cytosine,腺嘌和guanine,通过了diethylene乙二醇基于dimethacrylate的印胸腺嘧啶的聚合的膜,为模板分子胸腺嘧啶和它的最佳的模拟uracil的膜的识别被表明。因为它的高选择,作为cross-linker与diethylene乙二醇dimethacrylate准备的分子地印的膜可能对DNA的绝对hydrolysates的胸腺嘧啶试金或在生物样品的RNA的绝对hydrolysates的uracil试金适用,这被预言。
简介:Metalion-imprintedlycrosslinkedchitosanresin1andresin2werepreparedbytheuseofCu^2+andNi^2+astemplateionsandglutaraldehydeascrosslinkingagent,respectively,ThroughinvestigationontheadsorptioncapactiesandbindingconstantsforCu^2+,Ni^2+andCo^2+ionsonchitosanresins,resin1andresin2exhibittheadsorptionselectivityforthemixturesolutionof1L1Cu^2+andNi^2+ions.Theadsorptionselectivityofmetalion-imprintedresinsfortheirtemplateionsinmuchhigherthanthatofuncrosslinkedchitosanresin.