简介:双人脚踏车催化系统,由乙烯二度(indenyl)组成有二不同cocatalysts,alkylaluminum(diethylaluminium氯化物或trialkylaluminum)和methylaluminoxane的锆二氯化物,在作为唯一从乙烯准备分叉的聚乙烯被采用单体。催化系统racet(Ind)2ZrCl2/AlEt2Cl/MAO展出了高加入(29.0/1000C)。oligomerization和copolymerization反应在双人脚踏车调节催化系统,以及不同cocatalysts,在催化活动和获得的聚合物的性质有效果例如融化温度,crystallinity,分子的重量和分子的重量分发。而且,oligomerization反应条件是在改变聚乙烯的性质和结构的主要因素。
简介:Recently,Cristofaro-GardinerandHutchingsprovedthatthereexistatleasttwoclosedcharacteristicsoneverycompactstar-shapedhypersufaceinR~4.ThenGinzburg,Hein,Hryniewicz,andMacarinigavethisresultasecondproof.Inthispaper,wegiveitathirdproofbyusingindexiterationtheory,resonanceidentitiesofclosedcharacteristicsandaremarkabletheoremofGinzburgetal.
简介:AftercompositingthreerepresentativeENSOindices,ElNioeventshavebeendividedintoaneasternpattern(EP)andacentralpattern(CP).ByusingEOF,correlationandcompositeanalysis,therelationshipandpossiblemechanismsbetweenIndianOceanDipole(IOD)andtwotypesofElNiowereinvestigated.IODevents,originatingfromIndo-Pacificscaleair-seainteraction,arecomposedoftwomodes,whichareassociatedwithEPandCPElNiorespectively.TheIODmoderelatedtoEPElNioevents(namedasIOD1)isstrongestatthedepthof50to150malongtheequatorialIndianOcean.Besides,itshowsaquasi-symmetricdistribution,strongerinthesouthoftheEquator.TheIODmodeassociatedwithCPElNio(namedasIOD2)hasstrongestsignalintropicalsouthernIndianOceansurface.Intermsofmechanisms,beforeEPElNiopeaks,anomalousWalkercirculationproducesstronganomalouseasterliesinequatorialIndianOcean,resultinginupwellingintheeast,decreasingseatemperaturethere;acoupleofanomalousanticyclones(strongerinthesouth)formofftheEquatorwherewarmwateraccumulates,andthustheIOD1occurs.WhenCPElNiodevelops,anomalousWalkercirculationisweakerandshiftsitscentertothewest,thereforeanomalouseasterliesinequatorialIndianOceanislessstrong.Besides,theanticyclonesouthofSumatrastrengthens,andthesoutherlieseastofitbringcoldwaterfromhigherlatitudesandnortherlieswestofitbringwarmwaterfromlowerlatitudestothe15°to25°Szone.Meanwhile,thereexistsstrongdivergenceintheeastandconvergenceinthewestpartoftropicalsouthernIndianOcean,makingseatemperaturefallandriseseparately.Therefore,IOD2liesfarthersouth.
简介:Indoxacarb和metaflumizone属于钠隧道blocker杀虫药剂(SCBI)的一个相对新的班。由于indoxacarb的集中的使用,演变地的indoxacarb抵抗在几个鳞翅类的害虫被报导了,包括有菱形斑纹的蛾Plutellaxylostella,饰有十字架的庄稼的一个严肃的害虫。特别地,P的BY12人口。xylostella,从Baiyun镇定,在2012的中国的广东省,对indoxacarb和对metaflumizone更抵抗的70褶层更抵抗的750褶层与易受影响的Roth相比拉紧。编码Roth和BY12的钠隧道基因的互补DNA序列的比较在PxNa在BY人口的v蛋白质。两个变化位于被预言基于哺乳动物的钠隧道涉及局部麻醉和SCBI的有约束力的地点的一个高度保存的顺序区域以内。重要关联在在变异的等位基因(Y1845或I1848)之间的10张地镇定的人口之中被观察频率(1.7%~52.5%)和到indoxacarb(到870褶层的34-)和metaflumizone(到70褶层的1-)的抵抗层次。二个变化从来没被发现在PxNa建议他们独立地产生了的v,。这是钠隧道变化与抵抗的高水平被联系了到SCBI的第一次。F1845Y和V1848I是为在有菱形斑纹的蛾并且可能监视另外的昆虫害虫种类的抵抗的分子的标记。
简介:ThestrongadaptabilityofBroussonetiapapyrifera(L.)Vent.tolowphosphorus(P)conditionscanbeattributedtothelargeamountofroot-exudedorganicacidsandthehighef?ciencyofPextraction.However,microelementcontentsarein?uencedbylow-Pstress,andtheireffectsonthephotosyntheticcapabilityofB.papyriferaremainunknown.Inthisstudy,weinvestigatedtheeffectsoflow-Ptreatmentonnetphotosyntheticrate(P_N);chlorophylla?uorescence(ChlF)characteristics;andFe,Mn,Cu,andZncontentsofB.papyriferaandMorusalbaL.seedlings.ResultsshowthatB.papyriferaexhibitedbetterphotosyntheticcapabilityundermoderatePde?-ciency(0.125,0.063,and0.031mmol/LPtreatments),whereasthephotosyntheticcapabilityofM.albadecreasedundermoderateandseverePde?ciency(0.016and0mmol/LPtreatments).UndermoderatePde?ciency,thedecreaseinCuandZncontentsinB.papyriferawaslowerthanthatinM.alba.UnderseverePde?ciency,aconsiderabledecreaseofphotosyntheticcapabilityinB.papyriferaandM.albawasassociatedwithlowCuandZncontents.ThePNofthetwoMoraceaespeciesexhibitedabettercorrelationwithCuandZncontentsthanwithFeorMncontent.Pde?ciencycouldnotonlydecreasecyclicphotophorylationandphotosyntheticef?ciency,butcouldalsoaffectthestabilityofthylakoidmembranestructureandelectrontransportef?ciencybyin?uencingthecontentsofCuorZn,therebyaffectingphotosynthesis.
简介:连续统wavepacket干扰被数字地解决时间依赖者Schr调查?为有激光地的氢原子的相互作用的dinger方程。获得的wavepacket进化显示那,在over-the-barrier电离政体(1016W/cm2),电离的continuumcontinuum(CC)干扰电子在highorder泛音产生(HHG)成为主要过程,与连续统界限(CB)相比转移,由Kohler等报导了。[Phys。加快。Lett。105(20),203902(2010)].We为控制电离的量轨道建议一个二颜色的激光地计划电子并且为扩大CC泛音精力。作为结果,一个高精力平台发生在HHG光谱,它完全从CC泛音发源,与由二颜色的域的相对阶段可调节的截止。这在超级强烈激光地里提供原子和分子的动态特征的进一步的理解并且提供一个机会想象原子或分子的潜力。
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简介:Codfishisakindofabyssalfishspecieswithagreatvalueinfoodindustry.However,theflavorofcodfish,especiallytheunpleasantodor,hascausedseriousproblemsinitsprocessing.Toaccuratelyidentifythevolatilecompoundsincodfish,acombinationofsolidphasemicro-extraction(SPME)methodandsimultaneousdistillationextraction(SDE)methodwasusedtoextractthevolatiles.Gaschromatography-massspectrometry(GC-MS)alongwithKovatsindices(KI)andauthenticstandardcompoundswereusedtoidentifythevolatiles.Theresultsshowedthatatotalof86volatilecompoundswereidentifiedincodfish,ofthem24wereextractedbySDE,69compoundsbySPME,and10compoundsbybothSDEandSPME.Seventyvolatilecompoundswerefoundtohavespecificodors,ofthem7typicalcompoundscontributedsignificantlytotheflavorofcodfish.Alcohols(i.e.,(E)-2-penten-1-oland2-octanol),esters(i.e.,ethylbutyrateandmethylgeranate),aldehydes(i.e.,2-dodecenalandpentadecanal)contributedthemosttofreshflavorwhilenitrogencompounds,sulphurcompounds,furans,aswellassomeketones(i.e.,2-hydroxy-3-pentanone)broughtunpleasantodor,suchasfishyandearthyodor.ItwasindicatedthatthecombinationofmultipleextractionmethodsandGC-MSanalysiscanenhancetheaccuracyofidentification,andprovideareferenceforthefurtherstudyonflavorofaquaticproducts.
简介:Withthebirthofgraphenewithfasnicatingproperties,noveltwo-dimensionalnanomaterialshaveobtainedconsiderabledevelopmentsinthelastdecade.Amongthem,BNnanosheetshavebeenintensivelyinvestigatedbecauseoftheirlargeelasticmodulus,highmelting-point,superbthermalconductivityandlargedirectbandgap,whichcanbeusedinultraviolet-lightemitter,
简介:ItisnodoubtthatNewMissionofanOldState,BaiTongDong'srecentwork,ismoreremarkablethanmanycurrentresearchresultsincomparativestudiesofConfucianpoliticalphilosophy.IthasconductedinsightfulandinspirationalcomparisonandanalysisontherelationshipbetweenConfucianpoliticsanddomesticsociety.Theauthorisapprovedofmostofanalysisdetailsandconclusionsandhasnodoubtonitsresearchvalue.
简介:Two-dimensionalatomic-layeredmaterialisarecentresearchfocus,andsinglelayerTa2O5usedasgatedielectricinfield-effecttransistorsisobtainedviaassembliesofTa2O5nanosheets.However,theelectricalperformanceisseriouslyaffectedbyelectronicdefectsexistinginTa2O5.Therefore,spectroscopicellipsometryisusedtocalculatethetransitionenergiesandcorrespondingprobabilitiesfortwodifferentchargedoxygenvacancies,whoseexistenceisrevealedbyx-rayphotoelectronspectroscopyanalysis.SpectroscopicellipsometryfittingalsocalculatesthethicknessofsinglelayerTa2O5,exhibitinggoodagreementwithatomicforcemicroscopymeasurement.NondestructiveandnoncontactspectroscopicellipsometryisappropriatefordetectingtheelectricaldefectslevelofsinglelayerTa2O5.
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简介:Heavyionirradiationattractalargeinterestfortwoapplications:radiotherapyandspaceradiationprotectioninmannedspacemissions.ExposuretoheavyionsradiationresultsinmultipleeffectsthroughDNAdamageinduction.Single-cellgelelectrophoresisorcometassayisknownforitsabilitytodetectDNAdamageatthesinglecelllevelandhasbeenusedforyearstoassessDNAdamage.ItcandetectlowlevelsofDNAstrandbreaksinashorttime,justusingafewsamplecells.DNAdoublestrandbreaks(DSBs)aremeasuredattheneutralcometassaycondition;underthealkalinecometassayconditionbothDNAsinglestrandbreaks(SSBs)andpartDSBsaredetected.Thetwodimensionalcometassayisamodificationofthetwooriginalcometassay,cansimultaneouslydetectDNASSBsandDSBsinthesamehumanspermatozoa.
简介:Twonewcompounds,(22E)-25-carboxy-8β,14β-epoxy-4α,5α-dihydroxyergosta-2,22-dien-7-one(1)andfusidione(3),alongwithtwoknowncompounds,5α,8α-epidioxyergosta-6,22-diene-3β-ol(2)andmicroperfuranone(4),wereisolatedfromthefermentationproductsofthemarine-sourcedfungusAcremoniumfusidioidesRZ01.Thestructuresofcompounds1and3wereelucidatedbyextensivespectroscopicmethods,especially2DNMR,andtheirabsoluteconfigurationsweresuggestedonthebasisofthecirculardichroismspectralanalysisandtheNOESYdata.BothnewcompoundsshowedinhibitoryactivityagainstHL-60cellswithIC50valuesbeing16.6and44.9μmol·L-1,respectively.
简介:Soilmacroinvertebratesarehighlydiverseandtheirmajorecologicalserviceincludebreakdownoforganicmatterandinturnimprovesoilfertilityandpill-millipedesarewell-knownfortheirsigni?cantroleiningestion,disintegrationanddecompositionoforganicmatterinsoil.Thisstudycharacterizedthefeed,thedecomposingleaflitterofcoconut(Cocosnucifera),andfaecesoftwoendemicgiantpill-millipedesArthrosphaeradistictaandA.fumosacollectedfromforestsoftheWesternGhatsofIndiabasedonchemicalfeaturesandmicrobialpro?le.Inbothmillipedes,electricconductivityandtotalphosphorusweresigni?cantlyincreasedinfaeces,whilethecrudeprotein,organiccarbon,totalnitrogenandtotalphenolicsweresigni?cantlydecreased,ascomparedtothoseinfeed.Heterotrophicbacteria,actinomycetes,rhizobiaandphosphate-solubilizingbacteriaweresigni?cantlyhigherinfaecesthaninfeed,while?lamentousfungiandyeastsubstantiallydecreasedinfacescomparedtofeedinboththemillipedes.Spectrumoffattyacidmethylesterswasconsiderablydifferentbetweenfeedandfaecesofboththemillipedes.Thetotalsaturatedfattyacidswerehigherthanthetotalunsaturatedfattyacidsinfeedaswellasfaeces,whiletheratioofunsaturated/saturatedfattyacidsdecreasedfromfeedtofaeces.DodecanoicandtetradecanoicacidsinA.distictaandoctadecanoicacidinA.fumosasigni?cantlyincreased,while(9Z)-octadec-9-enoicand(9E,12E)-octadeca-9,12-dienoicacidsinA.distictaandhexadecanoic,tetracosanoicand(9E,12E)-octadeca-9,12-dienoicacidsinA.fumosasigni?cantlydecreasedinfaecescomparedtofeed,indicatingmillipede-dependentchangesinfattyacids.Icosanoicacidwaspresentinfaecesofboththemillipedes,andhexadec-9-enoicacidwascon?nedtofaecesofA.disticta,whilepentadecanoic,heneicosanoic,(9Z,12Z,15Z)-9,12,15-octadecatrienoicandeicosenoicacidswerecon?nedtofaecesofA.fumosa.Pill-millipedesenrichthesoilqualitybyleaflitterconditioningintheirgutthroughspeci?cmi
简介:Background:Seedproduction,seeddispersalandseedlingestablishmentarerelevantlifephasesofplants.Understandingtheseprocessesandtheirpatternsisessentialtorecognizevegetationdynamicsandtoapplyittoforestrestoration.Methods:ForOleaeuropaeaandScheffleraabyssinica,fecunditywasestimatedusingrandomizedbranchsampling.Seeddispersalandseedlingestablishmentweremonitoredusingspatiallyexplicitseedtrapsandplots.Dispersalfunctionswerecalibratedapplyinginversemodeling.Results:O.europaeaproducedmoreseedsandhadlongerdispersaldistancescomparedtoS.abyssinica.Correlationsbetweenobservedandpredictednumberofrecruitswerestatisticallysignificant.Seedlingsofthetwospeciesshoweddifferentnicherequirements.Conclusions:Thestudiedspecieswererecruitment-limitedduetolowdispersalactivityorlackofsuitablemicrosites.Restorationrelyingonnaturalregenerationshouldovercometheselimitationsbyincreasingdisperservisitationandreducingbioticandabioticstresses.