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1.
Youngman MJ  Green DB 《Talanta》1999,48(5):1993-1206
Microwave-assisted extraction (MAE) was examined as an alternative to the traditional Soxhlet method of extracting C60 and C70 from fullerene soot. MAE of 0.20 g of fullerene soot with 95:5 toluene–acetonitrile yielded greater than 7.8 mg of C60 and greater than 0.54 mg of C70 in 4 min with no further increase in yield after 30 min of irradiation. By comparison, exhaustive Soxhlet extraction of the same size sample with the same solvent yielded 7.1 mg of C60 and 0.58 mg of C70 in 340 min. Reextraction by MAE of soot initially extracted by Soxhlet increased the yield of Soxhlet alone. Although MAE was limited to less than 0.5-g sample per extraction vessel, multiple samples were extracted with minimal increased extraction time and no reduction in the amount of material recovered.  相似文献   

2.
综述了近年来C60及其卤化衍生物在阴离子聚合中的研究进展。在阴离子聚合中,C60可以直接与反应而进入主链,形成超枝化结构;C60可作为阴离子聚合的偶联剂,形成星形和线形结构;C60阴离子可以引发阴离子聚合。介绍了偶联产物结构控制的方法,以及偶联产物的稳定性。氯化富勒烯也可以作为阴离子聚合的偶联剂,生成星形结构聚合物。  相似文献   

3.
研究了C60分别在有机玻璃(PMMA)和正己烷中的吸收光谱,发现C60在有机玻璃中的吸收峰同在正己烷中相互对应,同时前者的吸收峰相对于后者峰宽变大,峰位产生红移,分析了产生这种现象的原因。  相似文献   

4.
Synthesis and Characterization of the Fullerene Co-Crystals C60 · 12 C6H12, C70 · 12 C6H12, C60 · 12 CCl4, C60 · 2CHBr3, C60 · 2CHCl3, C60 · 2H2CCl2 By crystallization of fullerenes from non-polar solvents (C6H12, CCl4, CHBr3, CHCl3, H2CCl2) compounds of the following compositions were obtained: C60 · 12C6H12, C70 · 12C6H12, C60 · 12CCl4, C60 · 2CHCl3, C60 · 2CHBr3 and C60 · 2H2CCl2. Lattice parameters have been determined by X-ray diffraction of powder samples; according to single-crystal examinations on C60 · 12C6H12, C60 · 12CCl4 and C60 · 2CHBr3 the fullerene is orientationally disordered. C60 · 12C6H12, cubic, a = 28.167(1) Å; C70 · 12C6H12, cubic, a = 28.608(2) Å; C60 · 12CCl4, cubic, a = 27.42(1) Å; C60 · 2CHBr3, hexagonal, a = 10.212(1), c = 10.209(1) Å; C60 · 2CHCl3, hexagonal, a = 10.08(1), c = 10.11(2) Å; C60 · 2H2CCl2, tetragonal, a = 16.400(1) Å, c = 11.645(7) Å.  相似文献   

5.
6.
Co-aggregation of fullerene C60 and thiophene has been studied calorimetrically in cyclohexene at 25 °C. The total aggregation heat is found to depend on initial concentration of thiophene and fall between −1.9 and −5.8 kJ mol−1. The corresponding thiophene/fullerene molar ratio (“co-aggregation number”) ranges from 7 to 12. The data are rationalized by formation of heteromolecular nanoaggregates with intermolecular contacts of both fullerene–thiophene and fullerene–fullerene types. A physical model describing interaction between fullerenes and π-donors in solution is substantiated and used to explain heterogeneity of composites containing fullerenes.  相似文献   

7.
8.
尽管目前人们对富勒烯[C60]的过渡金属有机物研究较多[1],但通过氮卡宾方式连接的C60二茂铁衍生物尚未见报道。鉴于对C60反应的浓厚兴趣及二茂铁的广泛应用价值[2]我们 利用C60的缺电子性[3]将其与二茂铁甲基氮卡宾进行[1+2]环加成反应,分离并表征了一种具有齿轮式结构的新奇C60二茂铁衍生物(CpFeC5H4CH2N)5C60(l)。  相似文献   

9.
The PM3, AM1, and MINDO3 semiemperical methods are used to calculate the the energy difference between C60ON and C60ON- and the bond dissociation energy necessary to cleave neutral and negatively charged (C60)2 dimers and epoxide dimers, (C60)2ON, to their respective monomers C60, and C60ON/2. The results show that the anions of the dimers are significantly more stable than neutral dimers. This result may explain the higher thermal stability of the observed ferromagnetic phase in photolyzed C60. which has been attributed to epoxide dimers and oligomers. It also provides an explanation for the origin of unpaired electron spin necessary for ferromagnetism.  相似文献   

10.
11.
The spectral analysis indicates that all isomers of C60O, C70O and C60O2 have an epoxide-like structure (an oxygen atom bridging across a C–C bond). According to the geometrical structure analysis, there are two isomers of fullerene monoxide C60O (the 5,6 bond and the 6,6 bond), eight isomers of fullerene monoxide C70O and eight isomers of fullerene dioxide C60O2. In order to simulate the real reaction conditions at 300 K, the calculation of the different isomers of C60O, C60O2 and C70O fullerene oxides was carried out using the semiempirical molecular dynamics method with two different approaches: (a) consideration of the geometries and thermodynamic stabilities, and (b) consideration of the ozonolysis mechanism. According to the semiempirical molecular dynamic calculation analysis, the probable product of this ozonolysis reaction is C60O with oxygen bridging over the 6–6 bond (C2v). The most probable product in this reaction contains oxygen bridging across in the upper part of C70 (6–6 bond in C70O-2 or C70O-4) an epoxide-like structure. C60O2-1, C60O2-3 and C60O2-5 are the most probable products for the fullerene dioxides. All of these reaction products are consistent with the experimental results. It is confirmed that the calculation results with the semiempirical molecular dynamics method are close to the experimental work. The semiempirical molecular dynamics method can offer both the reaction temperature effect by molecular dynamics and electronic structure, dipole moment by quantum chemistry calculation.  相似文献   

12.
The interaction between fullerene C60 and catalase enzyme was studied with a fullerene C60‐coated piezoelectric (PZ) quartz crystal sensor. The partially irreversible response of the C60‐coated PZ crystal sensor for catalase was observed by the desorption study, which implied that C60 could chemically react with catalase. Thus, immobilized fullerene C60‐catalase enzyme was synthesized and applied in determining hydrogen peroxide in aqueous solutions. An oxygen electrode detector with the immobilized C60‐catalase was also employed to detect oxygen, a product of the hydrolysis of hydrogen peroxide which was catalyzed by the C60‐catalase. The oxygen electrode/C60‐catalase detection system exhibited linear responses to the concentration of hydrogen peroxide and amount of immobilized C60‐catalase enzyme that was used. The effects of pH and temperature on the activity of the immobilized C60‐catalase enzyme were also investigated. Optimum pH at 7.0 and optimum temperature at 25 °C for activity of the insoluble immobilized C60‐catalase enzyme were found. The immobilized C60‐catalase enzyme could be reused with good repeatability of the activity. The lifetime of the immobilized C60‐catalase enzyme was long enough with an activity of 93% after 95 days. The immobilized C60‐catalase enzyme was also applied in determining glucose which was oxidized with glucose oxidase resulting in producing hydrogen peroxide, followed by detecting hydrogen peroxide with the oxygen electrode/C60‐catalase detection system.  相似文献   

13.
C60的加成反应   总被引:2,自引:0,他引:2  
唐光诗  董树安 《化学进展》1997,9(3):300-310
富勒烯化学是以全碳分子球烯为母体的新兴有机化学领域,在材料、医学及立体化学合成方法等方面具有广泛的应用和发展前景。本文综述了C60的加成反应,较全面地展示了富勒烯的化学性质。  相似文献   

14.
The interaction between fullerene C60 and heparin was studied using a fullerene C60‐coated piezoelectric quartz crystal sensor. The irreversible response of the piezoelectric quartz crystal was found which could be attributed to the quite strong adsorption of heparin onto the C60 molecule. Immobilized fullerene C60‐Heparin was prepared and successfully applied as a good inhibitor for blood clotting. Like solvated heparin, both wet and dry C60‐heparin solid all demonstrated excellent ability of anticoagulation of blood. The blood clotting time with C60‐heparin solid was found to be > 7 days, while only 17.9 min required for blood clotting time in the absence of C60‐heparin solid. Furthermore, the C60‐heparin coated artificial PVC blood vessels were prepared by coating fullerene C60 onto the surface of artificial PVC blood vessels, followed by the adsorption of water solvated heparin onto the fullerene C60 molecule to form C60‐heparin coating. The blood clotting time of blood in artificial PVC blood vessels with C60‐heparin coating was found to be > 30 days, while only ≤ 30 min. of blood clotting time without the C60‐Heparin coating was observed. The C60‐heparin coated artificial PVC blood vessels can be expected to be employed in human body for the anticoagulation of blood.  相似文献   

15.
A chemically bonded C60 silica phase was synthesized as a stationary phase for liquid chromatography (LC) and its retention behavior evaluated for various polycyclic aromatic hydrocarbons (PAHs) using microcolumn LC. The results indicate that the C60 bonded phase offers selectivity different from that of octadecylsilica (ODS) bonded phases in the separation of isomeric PAHs. With the C60 phase, PAH molecules having a partial structure similar to that of the C60 molecule, e.g. triphenylene and perylene, were retained longer than with ordinary ODS stationary phases. The results also show that good correlation exists between the retention data with this C60 bonded phase and with C60 itself as the stationary phase.  相似文献   

16.
Immobilized fullerene C60/anti‐insulin antibody was prepared and applied in shear horizontal surface acoustic wave (SH‐SAW) immunosensors to detect insulin in aqueous solutions. The immobilizations of anti‐insulin onto fullerene were studied through a C60/PVC coated SH‐SAW sensor system in liquid. The partially irreversible frequency response for an anti‐insulin antibody was observed by the desorption study, which implied that fullerene could chemically react with anti‐insulin. C60/anti‐insulin coating materials were successfully prepared and identified with an FTIR spectrometer. The C60/anti‐insulin coated SH‐SAW immunosensors were developed and applied for detection of insulin in aqueous solutions. Within the range of normal human insulin concentration, the SH‐SAW immunosensors immobilized with C60/anti‐insulin exhibited linear frequency responses to the concentration of insulin with a sensitivity of 130 Hz/pM. The SH‐SAW immunosensor immobilized with C60/anti‐insulin showed a detection limit of 0.58 pM for insulin in aqueous solution. The interference of various common bio‐species in human blood, e.g. urea, ascorbic acid, tyrosine, and metal ions, to the SH‐SAW immunosensor immobilized with C60/anti‐insulin for insulin was investigated. These common bio‐species interferences showed nearly no interference to the SAW immunosensors coated with C60/anti‐insulin. The reproducibility of the SH‐SAW immunosensor immobilized with C60/anti‐insulin for insulin was also investigated and is discussed.  相似文献   

17.
通过电化学方法合成了一种具有良好水溶性并能在水及空气中长期稳定存在的C60衍生物,经电泳实验证实该衍生物带负电荷。红外光谱及近红外光谱显示该水溶物有稳定键合的CO和OH基,所以表现出强亲水性。在可见区(从420nm到700nm)有非常宽的发光谱带,这是由于Jahn-Teller效应以及C60和OH基之间的相互作用引起的。  相似文献   

18.
C60甲苯介质聚结动力学研究   总被引:1,自引:1,他引:1  
应琦琮等[1]研究了C60-溶液的聚结动力学,发现在质量浓度0.78~1.29 mg*mL-1和室温(23 ℃~27 ℃)时为慢聚结.用分形理论得到维数为2.1;流体力学半径Rh=(0.64±0.01) nm;Meidine等[2]用X射线测定C60苯溶剂化的单晶(结构是C60*4C6H6,苯环平行于C60分子表面),溶剂苯中心到C60的距离为0.67~0.68 nm,与文献[1]的结果很接近.  相似文献   

19.
The catalytic hydrogenation of C60 on Ru, Rh and Ir produced C60H18 mainly, while Pd, Pt, Co and Ni catalysts gave C60H36 principally. Very little activity was observed on Au and Fe. The higher hydrogenated fullerene obtained on Pd, Pt, Co and Ni was ascribed to the smaller % d-character of the metallic bond, on which the fullerene and hydrogen may more strongly be adsorbed. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

20.
The rotation dynamics of C60 molecules in organic superconductor K3C60 has been investigated from the viewpoint of intramolecular interaction.It is determined that the rotation of C60 at room temperature has been frozen up within a small region of rotation angle (0→50°),and pointed out that the reason for the freeze is the physical interaction rather than the geometrical hindrance.The computations of the interactions for alkali-doped compounds A3-xAxC60(x=1,2,3;A,A'= K,Rb,Cs) other than K3C60 have also been carried out.From the obtained results,it is seen that the superconducting transition temperatures Tc are strongly connected with the interactions in them,and this observation is consistent with the discovery of the correlation between Tc and lattice constants a  相似文献   

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