天冬氨酸(ASP)自身热缩聚产物聚琥珀酰亚胺(PSI)通过与氨基化聚乙二醇单甲醚(α-胺基-ω-甲氧基-聚乙二醇)和十二胺(DDA)进行连续两步开环反应,制备了双亲性蜈蚣形聚合物聚琥珀酰亚胺接枝聚乙二醇与十二胺(PSI-g-PEG-DDA).随着改变疏水链段DDA的接枝比例,通过胶束粒径的变化确定了最佳的接枝比例.核磁共振波谱(1H-NMR)及凝胶渗透色谱(GPC)对聚合物的性质进行了表征.通过相转移法,聚合物对油溶性超顺磁性氧化铁纳米粒子进行包覆,制备了新型的水溶性超顺磁性氧化铁纳米粒子(PSI-g-PEGDDA@IONPs).动态光散射(DLS)和透射电镜(TEM)对新型的水溶性氧化铁纳米粒子的粒径与形貌进行了表征.体外T2核磁造影成像(MRI in vitro)确定了制备的氧化铁纳米粒子的R2质子驰豫率.肝癌小鼠模型的体内核磁造影成像(MRI in vivo)结果表明新型氧化铁纳米粒子对肿瘤部位有明显的T2核磁造影增强效应,并有很长的体内循环半衰期.以上实验结果表明,新型的水溶性纳米氧化铁粒子可以作为一种潜在的用于肿瘤检测的核磁造影剂.
A novel supramolecular sodium N,N-piperazinebis(methylenephosphonate) Na 2[(HO 3PCH 2)\5NC 4H 8N(CH 2PO 3H)](H 2O) 8·2H 2O, self-assembled into infinite 1D chains, was synthesized by the reaction of N,N-piperazine bis(methylenephosphonic acid) with NaOH. Its structure was characterized by single crystal X-ray diffraction, ICP and elemental analysis. The compound crystallizes in triclinic system, space group P1 with a=0.659 06(2) nm, b=0.726 73(2) nm, c= 1.158 25(4) nm, α=79.751(2)°, β=75.833(2)°, γ=74.122(2)°, V=0.513 68(3) nm 3, Z=2, D c=1.611 Mg/m 3, μ=0.331 mm -1, F(000)=264, S=1.098, R 1=0.045 2, wR=0.136 0. In the crystal, edge sharing octahedron Na 2O 10 dimers and tetrahedron PO 3C are assembled to an 1D chain via the bridges of heterocycle. 3D supramolecular framework is self-assembled from 1D chains through H-bonds.
This work describes a novel method to synthesize NaY zeolite at high temperature(100-140 ℃)by using NaY seeds solution as a silica source,which is also a method for the activation of silica source in the synthesis of NaY zeolite.Conventionally,the synthesis temperature of NaY zeolite from water glass is about 100 ℃,and higher temperature(>100 ℃)leads to the formation of impurity.However,this work shows that high-temperature synthesis(100-140 ℃)still exhibits a pure phase NaY.It is very interesting that,compared with conventional temperature,high-temperature in the synthesis of NaY zeolite has obvious advantages such as short crystallization time and high n(Si)/n(Al)ratio in the product.More importantly,this method is possible to extend to the synthesis of NaA,NaX,Ω,ECR-1and MOR.
提出了应用高效NaY沸石导向剂快速合成A型沸石的新方法.在合成过程中,NaY沸石导向剂提供了全部硅源(无需另加硅源).与用水玻璃提供硅源的合成方法相比,该法晶化速度快,合成温度低,并可在低碱度条件下合成超细A型沸石.29S i NMR表征和UV Ram an研究表明,高效NaY沸石导向剂中含有大量的六元环等低分子量硅铝酸根前驱体,它们有利于A型沸石成核与晶体生长.
