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A series of poly(methyl acrylate) copolymers of different pore structures were synthesized and functionalized by polyethylene polyamine.The lipase from porcine pancreas was adsorbed on these polymer carriers. It was found that the proe structure and functional group were basic factors which affected the activity of immobilized lipase,The optimal conditions for adsorbing lipase were studied and the effects of pH,ionic strength and temperature on the immobilized lipase were compared with those on the dissolved lipase. 相似文献
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Emulsifier-free emulsion polymerization of styrene in the presence of β-hydroxy propyl acrylate was studied.The emulsifier-free self cross linked polystyrene latex microspheres was obtained.Monomer conversion is higher than 90% when [St],[β-HPA],[KPS] is 2.66,0.228,and 5.8×10^-3mol/L respectively under 80℃ for 5h.The mono-dispersed latex particle diameter and colloidal particle concentration were given as D=0.23um,N=3.13×10^13/cm^3 by TEM analyse,The factors of influencing latex stability were discussed.Thecopolymer was characterized by IR and dissolution experiment.The apparent activation energy of polymerization and polymerization rate constant were obtained to be 78.7KJ/mol and 514.4/mol.s respectively. 相似文献
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1INTRODUCTIONRecently,considerableattentionhasbeenpaidtotheinvestigationofcoordinationchemistryofmanganeseindifferentoxidationstatesnotonlybecauseofthediscoveryoftightlyboundmanganeseatomsinvariousbiomolecules[libutalsobecauseoftheirinterestingstructural,magneticandspectroscopicfeatures.Wehavepreparedseveralcomplexesofmanganese(n)withdifferentligands.Thestructuresandfeaturesofthesecompoundsarestudiedsystematically.Inthispaperwedescribethestructureofthecomplexwiththeligandsofphenanthroline… 相似文献
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CRYSTAL STRUCTURE OF(Bu4N)2[Pt(C3S5)2] 总被引:1,自引:0,他引:1
<正> The title compound C38H72N2PtS10(Mr=1072.74)crystallizes in triclinic system,space group P1 with cell constants a=11.994(4),b=18.117(7),c=11.855(6)A,α=95.55(4),β=99.14(3),γ=75.71(3)°,V=2460.0A3,Z=2 and Dc=1.45 gcm-3.The structure is solved by direct methods and refined by full-matrix least-squares technique to final R=0.046 and Rw=0.045 based on 5919 independent reflections with I≥3.0(I).The anion [Pt(C3S5)2]2-is approximately planar,of which the platinum-sulfur coordination polyhedron takes a square form with mean Pt-S bond length of 2.310(4)A. 相似文献