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671.
富勒烯衍生物引发的富勒烯末端封端聚己内酯的合成   总被引:2,自引:1,他引:1  
利用带活性羟基的N-取代3,4-富勒烯吡咯烷作为引发剂,引发ε-己内酯开环聚合,制备了一种具有新型结构的富勒烯末端封端聚己内酯,通过核磁共振(1H NMR,13C NMR)、红外光谱(FTIR)和基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)等手段对产物进行了结构表征,并用热重(TG)分析和差示扫描量热(DSC)分析的方法进行了热学性能分析.结果表明,与聚己内酯相比产物热稳定性增加.  相似文献   
672.
利用紫外-可见吸收光谱、瞬态吸收光谱及X射线衍射等方法研究了苝醌染料竹红菌素镁离子配合物(Mg2+-HA)与富勒烯C60的相互作用. 结果表明, Mg2+-HA与C60在溶液和固体状态下都能够形成稳定的超分子. Mg2+-HA存在条件下, C60能够溶于多种极性溶剂, 在二甲基亚砜(DMSO)中的溶解度能够达到1×10-4 mol·L-1. 作为超分子体系中的光捕获分子, Mg2+-HA能显著地提高C60与N,N-二甲基苯胺(DMA)的光诱导电子转移反应效率, 生成的C60负离子自由基的电子自旋共振光谱(ESR)信号强度比未加入Mg2+-HA时增强了9倍左右.  相似文献   
673.
Fullerene black (FB) - a product of electric arc graphite vaporization after extraction of fullerenes - was modified with the di(2-ethylhexyl)phosphoric acid (D2EHPA). The distribution of D2EHPA between FB and aqueous HNO3 solutions has been studied. The effect of HNO3 concentration in the aqueous phase and that of D2EHPA concentration in the sorbent phase on the adsorption of microquantities of La, Ce, Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb, Lu, and Y nitrates from HNO3 solutions by D2EHPA-modified FB are considered. The stoichiometry of the sorbed complexes has been determined by the slope analysis method. The efficiency of lanthanides’ adsorption increases with an increase in the element atomic number. A considerable synergistic effect has been observed upon the addition of the neutral bidentate tetraphenylmethylenediphosphine dioxide ligand to D2EHPA in the sorbent phase.   相似文献   
674.
The AM1 semiempirical calculation method was employed to study the structures and electronic properties of a series of isoxazolo fullerene derivatives. Based on the AM1 geometry optimization, the electronic spectra of molecules were studied by using ZINDO/CIS methods. The results indicated the HOMO LUMO energy gaps of those isoxazolo fullerenes were lower than that of C60. There existed the intramolecular electron transfer from the additional section to C60 moiety. The electronic spectrum data showed that the exception of the absorption was beyond 400 nm.The results were in good accordance with the experiment results. Nonlinear optical susceptibilities α, β and γ of molecules were calculated according to Finite Field(FF)/AM1, and the influence of molecular structures on nonlinear optical properties was examined.  相似文献   
675.
We have recently developed methods of preparation of fluorofullerenes with specific fluorine content. Our previous successful synthesis of C60F36 and C60F18 with the use of transition metal fluorides inspired us to probe other high oxidation metal fluorides. In this work we report on the use of the binary lead fluorides (PbF2, PbF4, Pb2F6) and their complexes with alkali metal and alkaline earth metal fluorides (M2PbF6, M3PbF7 and M′PbF6) as fluorinating reagents for fullerenes.  相似文献   
676.
EFFICIENT POLYMER PHOTOVOLTAIC DEVICES BASED ON POLYMER D-A BLENDS*   总被引:1,自引:0,他引:1  
Recent work demonstrated that efficient solar-energy conversion could be achieved in polymer photovoltaic cells(PVCs) based on interpenetrating bi-continuous networks. In this paper we present a comprehensive study on improvingenergy conversion efficiencies of PVCs based on composite films of MEHPPV and fullerene derivatives. Carrier collectionefficiency of ca. 30% el/ph and energy conversion efficiency of 3.9% were achieved at 500 nm. At reverse bias of 15 V, thephotosensitivity reached 0.8 A/W, corresponding to a quantum efficiency over 100% el/ph. These results suggest that highefficiency photoelectric conversion can be achieved in polymer devices with M-P-M structure. These devices are promisingfor practical applications such as plastic solar cells and plastic photodetectors.  相似文献   
677.
新型共价键连的富勒烯-卟啉化合物的合成与表征   总被引:1,自引:0,他引:1  
为了构造一个具有有效电荷转移的给-受体体系,通过1,3-偶极加成反应,由5-[2-'(4″-醛基苯氧丙氧苯基)]-10,15,20-三苯基卟啉(H2P-CHO)、肌氨酸和C60首次合成了一种新的以共价键相连的富勒烯-卟啉配体(H2P-C60),同时用该配体制备了其锌配合物(ZnP-C60),并用红外光谱、元素分析、电子光谱、核磁共振氢谱和质谱等方法进行了表征.  相似文献   
678.
Elliptical carbon onions were produced from amorphous carbon by electron beam irradiation. Atomic structure and structural stability of the onion were investigated by high-resolution electron microscopy, molecular mechanics calculation and molecular orbital calculation, and a structure model of C24@ C84 was proposed at the center of the elliptical onion. Received 30 November 2000  相似文献   
679.
王乃兴 《合成化学》2000,8(5):422-424
将常用的有机催化剂如N,N′-二环乙基碳二亚胺、4-二甲氨基吡啶和1-羟基苯并三唑用于亚甲基「60」富勒烯羧酸的经典酯化反应,没有得到所期待的哑铃形偶联物,而得到单亚甲基富勒烯乙基酯,用柱色谱分离的产物经MALPI和FT-IR证实,并提出可能的反应机理。  相似文献   
680.
在ITO(indium-tin-oxide)透明电极和石英基片上,分别制备了两种C60吡咯环多羧基衍生物的自组装膜,并用接触角、紫外光谱和电化学循环伏安进行表征.测定了这两种自组装膜体系的光电转换性质,研究了电子受体、偏压和光强等因素对它的影响.  相似文献   
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