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Abstract: Fullerenes-extracted soot, the by-product of fullerene synthesis, is a carbon composite. The application of this material for water treatment has not yet been developed. Herein, fullerenes-extracted soot in the form of powder containing amino groups was prepared by reacting the soot with ethylenediamine, and was used as an adsorbent of hexavalent chromium [Cr(VI)] for removing Cr(VI) from aqueous solutions; this removal was studied by batch adsorption experiments. The effect of experimental parameters such as the pH, initial Cr(VI) concentration, and agitation time on the adsorption process was investigated. The adsorption of Cr(VI) was highly pH-dependent and the optimal pH for the adsorption process was 3.0. The data of Cr(VI) adsorption by fullerenes-extracted soot modified with ethylenediamine (FES-ED) fit the Langmuir isotherm equation well. The maximum Cr(VI)-uptake capacity of FES-ED was 93 mg g−1. The desorption of Cr(VI) from the adsorbent was also studied. The adsorbed Cr(VI) was eluted with 20 mL of an aqueous solution with pH 12 and the percentage recovery of Cr(VI) was determined as 75%. The adsorption and desorption test using the same FES-ED powder was repeated in triplicate to examine the reusability of the adsorbent. The adsorption was 97% and the desorption was >70% through the adsorption–desorption cycles. The adsorption of methyl orange onto the FES-ED was also examined. The dye was almost quantitatively removed from the aqueous solution by the adsorbent (the initial concentration of methyl orange: 40 μg mL−1; the adsorbent added: 10 mg/40 mL). Thus, we concluded that the FES-ED can be used as a novel adsorbent for removing pollutants from water. [Copyright &y& Elsevier]

Abstract: Acetalized [60]fullerenes were synthesized from cyclohexanone-fused [60]fullerene, which was facilely prepared by Diels–Alder reaction of C60 with silylether diene, on treatment of various aliphatic alcohols under TiCl4 catalyst. The spiro-cyclic acetalized [60]fullerenes having five, six, and seven-membered rings were also synthesized by using the corresponding diols under the same condition. The slightly raised reduction potentials E red (∼0.04V) relative to those of PCBM were observed by cyclic voltammetry measurement, depending on the identity of alkyl group/chain. The noncyclic acetalized [60]fullerenes showed lower thermal stability up to 200°C, while the cyclic ones exhibited the drastically improved thermal stability up to 350°C under nitrogen atmosphere. The acid-catalyzed hydrolysis easily removed the acetal moiety quantitatively, resulting in a considerable change of solvent solubility of the fullerene. [Copyright &y& Elsevier]

Abstract: We report a BF3-mediated novel dehydrative cycloaddition reaction of benzoquinones with stilbene oxides to afford 2,3-diaryl-5-hydroxybenzofurans and 2,3-diaryl-5-hydroxydihydrobenzofurans in good combined yields. No change in the products or the yield is observed when using diphenylacetaldehyde and cis-stilbene oxide instead of trans-stilbene oxides. When stilbene oxide is reacted with hydroquinone instead of the corresponding benzoquinone under the same conditions, dihydrobenzofuran is isolated in high yield. On the basis of these results, we propose the following possible reaction mechanism: stilbene oxide is converted to a phenonium ion (the key intermediate), which undergoes nucleophilic attack by benzoquinone or the simultaneously generated hydroquinone and subsequent dehydrative intramolecular cyclization to afford benzofuran or dihydrobenzofuran, respectively. [Copyright &y& Elsevier]

Objective: Intrauterine infection such as by Escherichia coli and Ureaplasma spp induce placental inflammation and are one of the leading causes of preterm birth. Here we evaluated hydroxylated fullerene (C60[OH]44) for its in vitro antiinflammatory and antioxidant effects against host cellular responses to the ureaplasma toll-like receptor 2 (TLR2) ligand, UPM-1. In addition, we investigated the preventative effects of C60(OH)44 in vivo in a mouse preterm birth model that used UPM-1.Study Design: TLR2-overexpressing cell lines and the primary cultures of mouse peritoneal macrophages were pretreated with C60(OH)44. After UPM-1 addition to the cell lines, the activation of the nuclear factor kappa-light chain-enhancer of activated B cells (NF-kappaB) signaling cascade and the production of reactive oxygen species were monitored. The levels of expression of inflammatory cytokines of interleukin (IL)-6, IL-1β, tumor necrosis factor (TNF)-α, and the production of reactive oxygen species were quantified after stimulation with UPM-1. The in vivo preventative effects of C60(OH)44 on mice preterm birth were evaluated by analyzing the preterm birth rates and fetal survival rates in the preterm birth mouse model with placental histological analyses.Results: Pretreatment with C60(OH)44 significantly suppressed UPM-1-induced NF-kappaB activation and reactive oxygen species production in TLR2-overexpressing cell lines. In the primary culture of mouse peritoneal macrophages, UPM-1-induced production of reactive oxygen species and the expression of inflammatory cytokines such as IL-6, IL-1β, and TNF-α were significantly reduced by pretreatment with C60(OH)44. In the UPM-1-induced preterm birth mouse model, the preterm birth rate decreased from 72.7% to 18.2% after an injection of C60(OH)44. Placental examinations of the group injected with C60(OH)44 reduced the damage of the spongiotrophoblast layer and reduced infiltration of neutrophils.Conclusion: C60(OH)44 was effective as a preventative agent of preterm birth in mice. [ABSTRACT FROM AUTHOR]

Highly fluorescent trans - and cis -tris(fluorenylphenylamino)benzene stereo-isomeric derivatives, trans - and cis -tris(DPAF-C 9 ), respectively, were designed and synthesized to minimize facile planar fluorene ring stacking in the solid state during thin-film device fabrications. Resulting tris-cup cis - and tris-chair trans -conformers were hypothesized to be capable of reducing direct packing contact of light-harvesting fluorene moieties from each other that should reduce the aggregation-related self-quenching effect derived from the π – π stacking packing arrangement. By the fact of closely matching photophysical characteristics of them to those of poly( N -vinylcarbazole) (PVK), we applied the former conformer as the secondary blue hole-transporting material in the study of its electroluminescence properties, using a tricomponent system of PVK‒ cis -tris(DPAF-C 9 )‒tris(2-phenylpyridine)iridium (III) [Ir(ppy) 3 ], as an example. Accordingly, several prototype single-layered or multilayered devices were fabricated with their electroluminescence and external quantum efficiency demonstrated. These analogous 3D-stereoconformers can also be used in other fluorescence-related thin-film applications. [ABSTRACT FROM AUTHOR]

Abstract: Encapsulation of C60, its hydroxides (C60(OH) n , n =10, 36, 44), and its hydride (C60H36) into inner space of carbon nanohorns (CNHs) from solutions or dispersions in various solvents by the nano-condensation method was attempted. The effect of the functional groups on the encapsulation was evaluated by transmission electron microscopy. C60, C60(OH)10, and C60H36 can be efficiently encapsulated inside CNHs using toluene, THF, and DMSO as solvents, whereas C60(OH)36 and C60(OH)44 are hardly encapsulated from any solution. Because the molecular size of C60(OH)10 is similar to that of C60(OH)36 and C60(OH)44, the difference in encapsulation is not caused by molecular size. The efficient encapsulation of C60H36 in CNHs suggests that molecules can be encapsulated in carbon nanomaterials even when the π–π interaction with the sp 2-hybridized carbon walls is weak. These results suggest the polarity of the functional group of the C60 derivatives as the main factor in determining whether they can be encapsulated in CNHs. C60(OH)36 and C60(OH)44 contain many hydroxyl groups, thus these molecules self-aggregate and do not pass the holes of CNHs, resulting in poor encapsulation. [Copyright &y& Elsevier]

We experimentally establish for the first time the influence of oxygen at carbon nanotube (CNT)-Cu interface on CNT/Cu composite electrical performances. We fabricated CNT/Cu films (CCF) with systematically varied oxygen interface characteristics through Cu electron beam deposition of CNT films functionalized by O 3 (g) exposure. By altering O 3 (g) exposure times (30–1000 s), different contents and types of interfacial O-functionalities (sp3C-O and sp2C O) were obtained. CCF with optimal interfacial oxygen type and content showed enhanced CNT-Cu wetting and improvement in 4-probe electrical conductivities and their temperature stability. For e.g., Cu/CNT with interface sp3C-O and sp2C O and O:C at% ratio ~4.6 × 10–1 showed 1.6 × and 1.8 × higher electrical conductivity at room temperature and 110 °C, respectively than composites with only sp3C-O interface and O:C at% ratio ~2.7 × 10–1. Favorable effects of interfacial oxygen in previous literature have chiefly focused on CNT/Cu mechanical performances. Systematic studies on electrical performances vs. interfacial oxygen content and type are absent. Our results fill this knowledge-gap and provide experimental evidence on benefits of optimally tailored interfacial oxygen functionalities for enhancing Cu-nanotube interactions and composite electrical performances. We believe our work will add to existing CNT/Cu interface tailoring toolkits in literature, aiding fabrication and application-development of lightweight composites with rivaling performances. [Display omitted] • Beneficial impact of O-interface in carbon nanotube(CNT)/Cu films(CCF) is reported. • CCF O-interface tailoring was done by CNT film O 3 (g) exposure before Cu deposition. • Varying O 3 (g) treat times led to various amounts of interfacial sp3C-O & sp2 C=O. • Optimal O-interface inclusion (content and type) improved CNT-Cu wetting in CCF. • Optimal O-interface improved CCF electric conductivity & its temperature stability. [ABSTRACT FROM AUTHOR]