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71.
《Composite Interfaces》2013,20(2-3):197-215
This study is focused on fabrication and characterization of multi-walled carbon nanotubes (MWCNTs) reinforced epoxy composites to understand variation of mechanical and thermal properties. Samples were prepared by infusing both amine functionalized and non-functionalized MWCNT into commercially available EL-350 epoxy resin. Flexure, quasi-static compression and high strain rate (HSR) tests were performed with 0.1%, 0.2% and 0.3% of MWCNTs to observe variation in mechanical properties. The optimum loading was found at 0.2%. Nanocomposites with amine functionalized MWCNTs showed better properties compared to that with unmodified MWCNTs. Scanning electron microscopy (SEM) analysis was performed to confirm an improvement in dispersion with functionalization. Thermal properties were investigated by thermogravimetric analysis (TGA). 相似文献
72.
《Composite Interfaces》2013,20(4):301-318
Polyacrylamide (PAM) doped by multiwalled carbon nanotube (MWNT) gels were prepared with different amounts of MWNTs varying in the range between 0.1 and 15 wt%. The PAM–MWNT composite gels were characterized by the steady state fluorescence technique (SSF). The alternative electrical conductivity (AC) of PAM–MWNT composite gels was measured by the dielectric spectroscopy technique. Observations around the gel point, t gel for PAM–MWNTs composite gels showed that the gel fraction exponent β obeyed the percolation result. The critical exponent r of AC electrical conductivity for the composite PAM–MWNT gel was also measured and found to be about 2.0, which agrees with a random resistor network. 相似文献
73.
《Composite Interfaces》2013,20(7):525-535
Reaction of herring-bone graphitic carbon nanofibers (GCNFs) containing surface-bound acid chloride functional groups with 3-aminopropyl triethoxysilane (APTES) leads to amide condensation and formation of carbon nanofibers surface-derivatized with pendant Si—OEt and Si—OH functional groups, GCNF-[C(O)NH(CH2)3Si(OEt)(OH)2] x . Addition of these GCNFs containing covalently bound 3-amidopropylsilyl linker molecules to silica sol-gel formulations gives GCNF/silica xerogels as dry black powders. Covalent binding of the linker molecule across the GCNF/ceramic interface is indicated by intermediate formation of especially stable GCNF/silica sol dispersions and the isolation of uniformly black GCNF/silica xerogel powders. SEM micrographs reveal excellent wetting of the carbon nanofiber surface by the silica xerogel matrix, and the presence of amido-carbonyl groups is confirmed from infrared spectral data. TGA plots show mass losses consistent with dehydration of the gel matrix and thermal decomposition of linker molecules at elevated temperature. 相似文献
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利用CO和NO作为双探针分子对Rh2Co2/Al2O3的吸附中心类型和吸附性能进行了详细的研究。结果表明Rh2Co2/Al2O3上存在Rh上的孪生和桥式CO吸附中心以及Co上的线式CO吸附中心。其中Rh上的孪生和桥式CO吸附中心对CO和NO的吸附性能与Rh4/Al2O3上的孪生和桥式CO中心相似。Co上的线式CO吸附中心以预吸附的CO能被NO取代, 预吸附的NO不能被CO取代而区别于Rh4/Al2O3上的Rh的线式CO吸附中心; 又以既能吸附CO又能吸附NO而不同于Co2/Al2O3和Rh+Co/Al2O3上的Co中心。与母体簇的结构相关联, 表明H2还原后的Rh2Co2/Al2O3上Rh2Co2(CO)12簇结构仍保持, 且Rh-Co相互作用强。 相似文献
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酰氧基甲酸酯热分解反应的量子化学研究 总被引:1,自引:0,他引:1
本文用AM1方法研究了酰氧基甲酸酯热分解反应的机理,结果表明这类化合物可消除二氧化碳得到酯,也可消除烯酮得到烷氧基甲酸,后者比前者易于进行 相似文献
79.
测定了15℃和30℃时炭黑自水和环己烷中吸附非离子型表面活性剂TritonX-100和Triton X-305的等温线;计算了吸附过程的标准热力学函数;测定了石墨/水/环己烷和石墨/水/空气的接触角与表面活性剂浓度的关系, 分析所得结果,可得结论:在炭黑/水或石墨/水界面上,Triton型表面活性分子形成单分子吸附层,分子以憎水的iso-C8H17C6H4基团附着在表面,而以亲水的聚氧乙烯链伸入水相的方式取向;在炭黑/环已烷或石墨/环己烷界面上,分子是通过聚氧乙烯链吸附到表面上的,当浓度增加时分子在表面可能通过聚氧乙烯链间的相互作用而发生聚集,即可能形成表面反式胶团。 相似文献
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本文研究了氮, 氧和二氧化碳在25℃, 10-15atm范围在全氟三丙胺(FTPA)和全氟萘烷(FDC)中的溶解度. 在上述压力范围内, 氮氧和二氧化碳三种气体的溶解度都符合Hanry定律, 测量误差在3%以内. 相似文献