简介:摘要:本文综述了水溶性聚合物的应用及其特点。重点介绍了其在传感器方面、组织工程及医疗领域中的应用。然而,水溶性聚合物的应用也存在一些挑战,如对环境的影响和生产工艺的优化等。因此,进一步研究水溶性聚合物的制备工艺和应用性能,将有助于其在不同领域中的发展和应用。
简介:摘要:树枝形聚合物是一类围绕中心核,外围链段随着代数的增加呈指数级别增长的支化大分子。与传统高分子相比,它具有高度的几何对称性,精确的分子结构,分子内存在空腔,分子大小为纳米尺寸等特点。在树枝形聚合物的核心、骨架和外围修饰上各种功能基团可以实现树枝形聚合物的功能化。本文通过对树枝形聚合物发展历史的梳理浅析其应用。
简介:摘要:树枝形聚合物是一类围绕中心核,外围链段随着代数的增加呈指数级别增长的支化大分子。与传统高分子相比,它具有高度的几何对称性,精确的分子结构,分子内存在空腔,分子大小为纳米尺寸等特点。在树枝形聚合物的核心、骨架和外围修饰上各种功能基团可以实现树枝形聚合物的功能化。本文通过对树枝形聚合物发展历史的梳理浅析其应用。
简介:【摘要】:幼儿健康成长,需要家庭和幼儿园的通力合作。家园共育在幼儿成长的道路上发挥着极其重要 的作用。家园沟通是家园共育的有效途径。只有家长与教师之间形成有效的沟通,才能共同商讨、解决 幼儿成长中出现的问题,从而搭起幼儿健康成长的桥梁。但是,现实中,在家园沟通中还存在不少的问题,需要家园双方的大力配合,采取有效措施,积极推进家园沟通工作的顺利展开。
简介:本发明属于用于双烯烃聚合或共聚合的稀土催化剂的制备方法。该稀土催化剂制备方法的步骤和条件如下:在氮气保护下向干燥的催化剂配制器中依次加入上述的稀土卤化物的醇合物(LnX3·nROH),单体,烷基铝(Al)的饱和烃溶液。各组分之间的摩尔比:Al与Ln的摩尔比为10-200,单体与Ln的摩尔比为2-50。于40-100℃下陈化5分钟-24小时待溶液变色后,得到用于双烯烃聚合或共聚合的稀土催化剂。该催化剂适用于双烯烃聚合或共聚合,聚合在有机溶剂存在下也可在无溶剂情况下进行;该催化剂的组成为卤化稀土醇合物、烷基铝及单体:在高温下陈化待溶液变色后具有较高的催化活性,能制得顺-1,4结构,含量高于95.8%、高分子量的聚异戊二烯。
简介:AsthetopologicalpropertiesofeachspotinDNAmicroarrayimagesmayvaryfromoneanother,weemployedgranulometriestounderstandtheshape-sizecontentcontributedduetoasignificantintensityvaluewithinaspot.Analysiswasperformedonthemicroarrayimagethatconsistedof240spotsbyusingconceptsfrommathematicalmorphology.Inordertofindoutindicesforeachspotandtofurtherclassifythem,weadoptedmorphologicalmultiscaleopenings,whichprovidedmicroarraysatmultiplescales.Successiveopenedmicroarraysweresubtractedtoidentifytheprotrusionsthatweresmallerthanthesizeofstructuringelement.Spot-wisedetails,intermsofprobabilityoftheseobservedprotrusions,werecomputedbyplacingaregularlyspacedgridonmicroarraysuchthateachspotwascenteredineachgrid.Basedontheprobabilityofsizedistributionfunctionsoftheseprotrusionsisolatedateachlevel,weestimatedthemeansizeandtextureindexforeachspot.Withthesecharacteristics,weclassifiedthespotsinamicroarrayimageintobrightanddullcategoriesthroughpatternspectrumandshape-sizecomplexitymeasures.Thesesegregatedspotscanbecomparedwiththoseofhybridizationlevels.
简介:Apoptosiscanbetriggeredbyavarietyofstimuliincludingdeathfactors,anti-cancerdrugsandfactor-deprivation.Theseapoptoticcellsareswiftlyphagocytosedbymacrophagestopreventthereleaseofnoxiousorinflammatorymaterialsfromdyingcells.ThemolecularanalysisofFasligand(adeathfactor)-inducedapoptosisindicatedthatacascadeofproteases(caspases)isactivatedduringthisprocess,whicheventuallyactivatesaspecificDNase(caspase-activatedDNase).CADexistsasacomplexwithitsinhibitor(ICAD)inproliferatingcells.Whenthecellsaretriggeredtoapoptosis,caspases,inparticularcaspase3,inthedownstreamofthecaspasecascadecleaveICAD,whichreleasesCADtocauseDNAdegradationinnuclei.
简介:ThebindingofCo(bpy)2dppz3+tocalfthymusDNAwasinvestigatedbyusingabsorptionandemissionspectroscopy,DNAmeltingtechniques,cyclicvoltammetry,viscosityandelectro-phoresismeasurements,wherebpyis2,2’-bipyridyl,dppzisdipyrido[3,2-o:2’,3’-c]phenazine.Thebindingcompoundshowsabsorptionhypochromicity,fluorescenceenhancement,andincreasingofDNAmeltingtemperatureandthespecificviscosity.CVmeasurementshowstheshiftsinoxidation-reductionpotentialandchangeinpeakcurrentwithadditionofDNA.ThecompoundisalsoshowntobemoreefficientphotosensitisersforstrandbreaksinplasmidDNA.
简介:DNAcondensationisanimportantprocessinmanyfieldsincludinglifesciences,polymerphysics,andappliedtechnology.Inthenucleus,DNAiscondensedintochromosomes.Inpolymerphysics,DNAistreatedasasemi-flexiblemoleculeandapolyelectrolyte.Manyagents,includingmulti-valentcations,surfactants,andneutralpoorsolvents,cancauseDNAcondensation,alsoreferredtoascoil–globuletransition.Moreover,DNAcondensationhasbeenusedforextractionandgenedeliveryinappliedtechnology.ManyphysicaltheorieshavebeenpresentedtoelucidatethemechanismunderlyingDNAcondensation,includingthecounterioncorrelationtheory,theelectrostaticzippertheory,andthehydrationforcetheory.Recentlyseveralsingle-moleculestudieshavefocusedonDNAcondensation,sheddingnewlightonoldconcepts.Inthisdocument,themulti-fieldconceptsandtheoriesrelatedtoDNAcondensationareintroducedandclarifiedaswellastheadvancesandconsiderationsofsingle-moleculeDNAcondensationexperimentsareintroduced.
简介:TheeffectofCdionsonsalmonspermDNAwasstudiedbymeansofcirculardichroism(CD),Ramanspectroscopy,X-rayphotoelectronspectroscopy(XPS)andfluorescencespectroscopy.TheCDspectralandfluorescentprobe-acriflavineresultsindicatethattheDNAunderwentaconformationchangeupontheadditionofCdions.XPSandRamanstudiesrevealthatthereexistedinteractionsbetweenCdionsandthephosphategroupsoftheDNA.Inaddition,anewbandappearedat803cm-1intheRamanspectra,whichcanbeattributedtocharacterizing"marker"bandofA-DNA.ItisconcludedthatCdionscanbecoordinatedbythephosphategroupsoftheDNAandinducetheconformationchangesoftheDNAfromB-DNAtoA-DNA.