Co/CoO/C@B three-phase composite derived from ZIF67 modified with NaBH4 solution as the electrocatalyst for efficient oxygen evolution
ELECTROCHIMICA ACTA
Authors: Wei, Xuedong; Li, Na; Zhang, Xianming
Abstract
Two kinds of three-phase composite materials, Co/Co(OH)(2)/C@B directly from ZIF67 modified by NaBH4 and Co/CoO/C@B through pyrolyzation of Co/Co(OH)(2)/C@B material, are successfully synthesized and used as catalysts for the oxygen evolution reaction (OER). The structure and morphology are mainly characterized by X-ray diffraction (XRD), high resolution transmission electron microscopy (HRTEM), energy dispersive X-ray analysis (EDX), X-ray photoelectron spectroscopy (XPS). HBZ-1 sample with the structure of Co/Co(OH)(2)/C@B has the best onset potential of 1.075 V vs. RHE at 0.1 mA cm(-2) and the best catalyst stability among all of the materials researched. Especially as its pyrolyzing product, the CBZ-1 sample with the structure of Co/CoO/C@B behaves the most excellent synthetically electrocatalytic performance with low onset potential of 1.444 V vs. RHE at 0.1 mA cm(-2) and a small overpotential of 390 mV at 10 mA cm(-2), which is better than that of RuO2. This good catalytic activity is mainly attributed to the generation of CoO phase and synergistic effect of all the phases in the composite structure. Furthermore, the CBZ-1 sample has the appropriate catalytic stability which attributed to the three-phase structure of Co/CoO/C@B composite and the existing of a little B element. (c) 2018 Elsevier Ltd. All rights reserved.
Requirement of the human T-cell leukemia virus p12 and p30 products for infectivity of human dendritic cells and macaques but not rabbits
BLOOD
Authors: Valeri, Valerio W.; Hryniewicz, Anna; Andresen, Vibeke; Jones, Kathy; Fenizia, Claudio; Bialuk, Izabela; Chung, Hye Kyung; Fukumoto, Risaku; Parks, Robyn Washington; Ferrari, Maria Grazia; Nicot, Christophe; Cecchinato, Valentina; Ruscetti, Frank; Franchini, Genoveffa
Abstract
The identification of the genes necessary for human T-cell leukemia virus (HTLV-1) persistence in humans may provide targets for therapeutic approaches. We demonstrate that ablation of the HTLV-1 genes encoding p12, p30, or the HBZ protein, does not affect viral infectivity in rabbits and in this species, only the absence of HBZ is associated with a consistent reduction in virus levels. We observed reversion of the HTLV-1 mutants to the HTLV-1 wild-type genotype in none of the inoculated rabbits. In contrast, in macaques, the absence of HBZ was associated with reversion of the mutant virus to the wildtype genotype in 3 of the 4 animals within weeks from infection. Similarly, reversion to the wild type was observed in 2 of the 4 macaque inoculated with the p30 mutant. The 4 macaques exposed to the p12 knock remained seronegative, and only 2 animals were positive at a single time point for viral DNA in tissues. Interestingly, we found that the p12 and the p30 mutants were also severely impaired in their ability to replicate in human dendritic cells. These data suggest that infection of dendritic cells may be required for the establishment and maintenance of HTLV-1 infection in primate species. (Blood. 2010;116(19):3809-3817)