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Nine novel heteronuclear complexes of Ln(Ⅲ)-Cu(Ⅱ) with salicylidene tetraethvlcne glycol diamine (SALTTA) have been synthesized and characterized.They have the general formulae [LnCu2(SALTTA)2(NO3)3](NO3)4 3H2O (Ln=La,Pr.Nd,Srn) and [LnCu3(SALTTA)3(NO3)5]-(NO3)4-4H2O (Ln=Gd,Tb,Er,Yb,Y).The IR spectra show that vc=N in the Ln(Ⅲ)-Cu(Ⅱ) het-eronuclear complexes are splitted up into two peaks with a far distance.It has been confirmed that oxygen atoms in oxyethylene of the ligand are not all coordinated to the central metal ions by both IR and NMR methods. 相似文献
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研究与探讨了多C==N—基空间不对称Schiff碱的合成, 合成了含有2个以上不同位置C==N— 基团的Schiff碱, 即四甘醇醛和2,4-二羟基苯甲醛缩双赖氨酸(TBLY)与稀土的配合物, 经元素分析、磁化率、光谱及1H NMR, 1H,1H COSY, 13C NMR谱等表征, 确定其组成为Ln3(TBLY)(NO3)3·nH2O (Ln = La, n= 3; Ln = Nd, n= 5; Ln = Gd, Dy, Yb, Y, n= 7). 以半经验量子化学AM1法计算并探讨了在红外光谱和核磁共振谱中所观察到的烯胺键的存在. 该类新Schiff碱配合物不需助催化剂即可单独催化聚合甲基丙烯酸甲酯(MMA), 转化率可达80%, 黏均分子量约为22万. 相似文献
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Three ethylene-vinyl alcohol copolymers were studied by means of the substituent chemical shift (SCS) method. The SCS parameters of hydroxy (-OH) in two different solvents were obtained: in deuterium oxide/phenol (20/80 W/W ) the parameters are S_1 = 42.77±0.08ppm, S_2 = 7.15±0.06 ppm, S_3 (s)= -4.08±0.02ppm, S_3 (t) =-3.09±0.20ppm,S_4 = 0.48±0.03ppm, S_5 = 0.26±0.05ppm. In o-dichloro-benzen-d_4 S_1(s)=44.79±0.61ppm, S_2=7.40±0.00ppm, S_3(s)=-4.51±0.17ppm, S_3(t)=-3.13 ±0.00 ppm, S_4 =0.63±0.04ppm, S_5=0.36±0.00ppm.Simultaneously the ~(13)CNMR spectra of EVA copolymers were assigned by using the SCS parameters obtained. 相似文献
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稀土与四甘醇醛缩苯丙氨酸Schiff碱配合物的合 成、性能与催化 总被引:3,自引:0,他引:3
合成了直链醚-氨基酸新型Schiff碱(四甘醇醛缩苯丙氨酸Schiff碱)及其与稀土新配合物,[Ln~3L~2(NO~3)~2]·(NO~3)~3·nH~2O(Ln=La,Nd,Sm,n=3;Ln=Gd,Dy,Er,Y,n=5),以元素分析、磁化率、红外光谱、^1HNMR等进行了表征,研究了的配位作用,根据预期设想,见到此类配合物在有机溶剂中的溶解性有明显改善。以EPR波谱探讨了配合物的晶体场强,并计算了晶体场参数。此外,发现在不加助催化剂条件下,此类配合物对MMA(甲基丙烯酸甲酯)聚合有一定的催化效果。 相似文献
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