简介:Letr,1p={f:fr-1isabs.cont.onI=[a,b],fisperiodiewithperiodH(=b-a),f(x1)=0,‖f(r)‖p≤0},wherex1isanyfixedpointin[a,b].TheauthorfindstheKolmogorov,Gel’land,linear,andBerusteinn-widthsofr,1pinLp(I)fornodd,∞>p>1.Theoptimalsubspacesandoperatorsarealsofound.
简介:通过一种取代剂将N-乙基-α-萘胺生产中副产品N,N-二乙基-α-萘胺转化产品N-乙基-α-萘胺.经试验考查了温度、时间以及反应物配比对转化反应收率的影响,确定了最佳操作条件:温度165℃,时间4小时,物料配比1:5(摩尔比).转化反应的总收率为78.4%.由于副产品N,N-二乙基-α-萘胺的转化利用,使N-乙基-α-萘胺产品收率由68.9%提高至84.3%。
简介:NineteenL-N-2-hydroxyethylaminoacidsandL-N,N-bis(2-hydroxyethyl)aminoacidswerepreparedfromthereactionofchlorohydrinwithL-alanine,L-valine,L-leucine,L-isoleucine,L-phenylalanine,L-serine,L-thrcunine,L-glutamicacid,L-asparticacidandglycine.L-N,N,N’,N’-tetra(2-hydroxyethyl)cystinewaspreparedbythereactionofL-cystinewithchlorohydrin.
简介:用荧光光谱法研究了298K下Tris—HCl缓冲溶液(pH=7.1)中不同离子强度下,季铵盐类表面活性剂N-十四烷基-N-羟乙基-N,N-二甲基溴化铵(THDAB)与牛血清白蛋白(BSA)的结合作用.考察了离子强度对二者结合作用的影响,分别用Stern.Volmer方程、位点结合模型探讨了THDAB在浓度较低区域与BSA的作用机制,用位点结合模型计算了不同离子强度下THDAB和BSA结合反应的结合常数K-A和结合位点数n.结果表明:随离子强度的增大,THDAB与BSA的结合作用减弱.
简介:Thecrystalandmolecularstructureofcopper(Ⅱ)dimericcomplexofS-methyl-B-N-(pyridineN-oxide-2-ylmethylidene)dithiocarbazatewithacetonitrile,[CuL(CH3CN)]2(ClO4)2,wasdeterminedbyX-raydiffraction.ThecomplexcrystalizesinmonoclinicsystemwithspacegroupP21/n,a=7.685(2),6=20.160(6),c=10.847(5)A,B=107.89(3),Z=2,Dc=1.788g/cm3,F(000)=835.8,u=18.17cm-1(Moka,R=0.057.EachCu(Ⅱ)ioninthecomplexissurroundedbyadistortedsquarepyramidal.ThebasalplaneiscomprisedofS,NandOatomsofoneligandtogetherwithaNatomofthesolvent--acetonitrile,whiletheaxialpositionisoccupiedbytheSatomoftheotherligand.ThebondlengthofCu-S(bridging)is3.038A.andCu-Cudistanceis3.700A.
简介:AnewchemilurninescencelabelN-(β-carboxypropionyl)luminol(CPL)wasusedtolabelsheepanti-humanIgG(SaHIgG).Thelabeledantibodywasstableandcouldbedetectedatleastdownto10-17~10-16mol.Themolarincorporationratiowasestimatedtobe0.26molofCPLpermolofSaHIgG.TherewerenoapparentchangesintheimmunoreactivityofthelabeledSaHIgGandinthequantumefficiencyoftheCPLafterlabeling.
简介:乙酸(1-二茂铁基乙基)酯1与二甲胺反应制备出N,N-二甲基-1-二茂铁乙胺2,收率74%.在正丁基锂/乙醚的反应体系中,化合物2进一步与二苯基氯化磷反应,制备出N,N-二甲基-1-(2-二苯膦基)二茂铁乙胺3,收率18%.化合物3的结构经1HNMR和31PNMR进行了表征,并进一步研究了其合成机理.