简介:Threepolymericadsorbentswithhydrogenbondingacceptors,methylamine,N-methyl-acetamideandaminotri(hydroxymethyl)methanemodifiedresinsaresynthesizedfromchloromethylatedX-5resin.AdsorptionisothermsofphenolandtheophyllineontothethreemodifiedresinsandtheoriginalX-5resinfromaqueoussolutionaremeasured.TheresultsshowthatadsorptionofcompoundswithhydrogenbondingdonorontomethylamineandN-methylacetamidemodifiedresinsisenhancedascomparedwiththatontoX-5resin,andadsorptionmechanismbetweentheadsorbentsandtheadsorbatesismainlybasedonhydrogenbondingandhydrophobicinteraction.Whileadsorptionofcompoundswithhydrogenbondingdonorontoaminotri(hydroxymethyl)methanemodifiedresinisloweredascomparedwiththatontoX-5resin,andadsorptionmechanismbetweentheadsorbentandtheadsorbatesismainlybasedonhydrophobicinteraction.
简介:Thetransitionsandmorphologyofaseriesofmain-chainliquidcrystallinepolymerwithX-shapedmesogenswerestudiedbymeansofDSC,SALSandpolarizingmicroscopytechniques.Aneven-oddeffectwasobservedforsampleswithdifferentsizeofthesubstituentsonthemesogenends.Theisotropizationprocesswassimilartothatofmain-chainpolymerswithrod-likemesogens.Nocrystallizationwasdetectedforspecimenscoolingdownfromtheirisotropicmeltstate.Howevertwoofthesamplesmaycrystallizeincoolingprocessdirectlyfromtheliquidcrystallinestate.
简介:Thecopolymersofchloroethylmethacrylate(CMA),glycidylmethacry-late(GMA),andmethylmethacrylate(MMA)weresynthesizedinbenzenesolution.Theirbreadthsofthemolecularweightdistributionsare2.1and2.3,respectivelyThether-malstabilityofP(GMA-CMA)issuperiortothatofP(CMA-MMA).TheresolutionsofP(CMA-MMA)andP(GMA-CMA)photoresistswerefoundtobe0.1~0.16μmand0.17~0.2μm,respectively.
简介:无论是以前的村民代表大会,还是现在的议事会,其面临的主要问题,都是如何解决决策权的虚设问题高仁天被逼着做了一次"官"。这个已经做了14年司机的邛崃市油榨乡马岩村农民,去年3月底被同组村民推举
简介:BymeansoftheintensitytheoryofX-rayscatteringandthetwo-phaseconceptofhighpolymer,thebasicformulaofthecrystaUinityinblockcopolymershasbeenproposedafterthecorrectionsofatomic,temperature,absorption,Lorentzandpolarizationfactor.Applicationofthismethodtodifferenttypepoly(oxyethylene-styrene)blockcopolymersandthesametypeblockcopolymerswithdifferentEOcontentsindicatesthatthecrystallinityinpoly(oxyethylene-styrene)blockcopolymersincreaseswiththeincreaseoftheEOcontentanddecreasesintheorder:PEO-PS-PEO>PEO-PS>PS-PEO-PS.