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991.
We have applied DFT calculations to devise some (SiH)48X12 heterofullerenes with replacing of 12 Si–H units with a series of the group III and V dopants, P, N, As, B, Al and Ga, with the configuration of one dopant per pentagonal ring. Our results indicate that binding energies of heterofullerenes with group III dopants are smaller than those of heterfullerenes with group V dopants. Density of state obtained for the systems indicate a distinct change near the valence level compared to that of Si60H60, and a local energy level appears after the doping. (SiH)48X12 heterofullerenes with the group III and V dopants are composed of positively and negatively charged dopant atoms, each of which is surrounded by opposite charged Si atoms. The electrophilicity values of (SiH)48X12 heterofullerenes, except for (SiH)48N12, are greater than that of their parent. Because of the higher electronegativity of group V elements and electron transfer from the cages to the group V dopants, electrophilicity values for the (SiH)48X12 heterofullerenes with the group V dopants are always smaller than those of heterofullerenes with the group III dopants. 相似文献
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Research on Chemical Intermediates - Grafting of 4-(sulfoamino)butanoic acid on superparamagnetic γ-Fe2O3@SiO2 nanoparticles afforded γ-Fe2O3@SiO2@4-(sulfoamino)butanoic acid as a novel... 相似文献
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Mohammad Reza Shahsavari Alireza Namjoo Hossein Mohammadian Younes Saadat Soleyman Hosseinzadeh Samira Abdolbaghi 《Colloid Journal》2016,78(3):415-424
Dual-seeded dispersion polymerization (DSDP) of 2-ethylhexyl methacrylate with polystyrene (PS) and poly(methyl methacrylate) (PMMA) seed beads in the presence of saturated hydrocarbon droplets followed by evaporation of the hydrocarbon was studied. The effect of various polymerization conditions including initiator type and content, stabilizer type and concentration, and different hydrocarbon’s content on the shape of the obtained particles was investigated. The increase of concentration of 2,2'-azobis(isobutyronitrile) (AIBN) had no effect on the shape of the produced almond-shell-like PS particles, although it contributes in the formation of associated composite particles along with larger poly(2-ethylhexyl methacrylate) (PEHMA) beads produced by secondary nucleation. The experimental results showed that other initiators led to the formation of stable golf-ball-like PMMA particles as well as PS ones with symmetric shape. The type of stabilizer did not affect the shape of the particles. This observation suggests that unique almond-shelllike PS particles can be produced through a stabilizer-free DSDP process. The lowering of the concentration of hydrocarbons with long alkyl chains yielded stable disc-like PMMA particles. The formation of functional almond-shell-like particles by using light hydrocarbons was another interesting finding of this research. 相似文献
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