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Cobalt carbides nanoparticles have great potential as novel materials in magnetic fields. However, it is difficult to synthesize single phase cobalt carbides, especially Co3C. In this paper, we propose a one‐pot wet‐chemistry approach to synthesize single phase ferromagnetic Co3C without using any alkali as nucleation solvent. The particle size of Co3C nanoparticle is about 3 nm. The magnetic properties of Co3C nanoparticles are measured at 300 K from –30 to 30 kOe. Compared with Co2C, Co3C exhibits a large saturation magnetization of 46.1 emu g–1 and a high coercivity of 1.5 kOe. Small amount of carbon and small particle size of the Co3C nanoparticle are believed to contribute to large magnetization and high coercivity. Magnetic measurements also reveal the spin glass behavior caused by the small Co3C nanoparticle at the spin freezing temperature of 43 K. This work provides a facile method to synthesize single phase Co3C nanoparticle which is applicable in magnetic field. [ABSTRACT FROM AUTHOR]

Neuron-restrictive silencer factor (NRSF) blocks the expression of many neuronal genes in non-neuronal cells and neural stem cells. There is growing body of evidence that NRSF functions in mature neurons and plays critical roles in various neurological disorders. Our previous study demonstrated that the expression of NRSF target genes brain-derived neurotrophic factor ( BDNF ), and tyrosine hydroxylase ( TH ) is transiently decreased in 1-methyl-4-phenyl-pyridinium ion (MPP + )-treated SH-SY5Y cells. NRSF neuronal deficient mice are more vulnerable to 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). Here we investigated the effect of epigenetic modulation on the expression of NRSF target genes in in vitro and in vivo models of Parkinson's disease (PD). Trichostatin A (TSA) was further used to study the effects of histone deacetylase inhibition on NRSF-mediated repression. We found that the repression of NRSF target genes was relieved by TSA in vitro . A single dose TSA pretreatment also upregulated the expression of TH and BDNF and protected the nigrostriatal dopaminergic pathway against MPTP-induced degeneration in wild type mice. However, the protective functions of TSA were fully abolished in NRSF neuronal deficient mice. Our results suggest that NRSF serves as an essential mediator for the neuroprotection of TSA in the MPTP model of PD. [ABSTRACT FROM AUTHOR]

Abstract: Fe/SiO2 Fischer–Tropsch synthesis (FTS) catalysts using tetraethoxysilane (TEOS) and acidic silica sol (AcSS) respectively as silica sources were prepared by co-precipitation method. The catalysts were studied through N2 adsorption, X-ray diffraction, Mössbauer effect spectroscopy, and temperature-programmed reduction and desorption. The FTS performances of catalysts were evaluated in a fixed-bed reactor at 280°C, 1.5MPa, 2000h−1, and H2/CO molar ratio of 2. The characterization results indicated that the TEOS derived catalyst displayed a more uniform pore size distribution, easier reduction and higher capability for CO and H2 adsorption than the AcSS derived catalyst. In FTS reactions, the TEOS derived catalyst showed higher activity and C5 + selectivity than the AcSS derived catalyst. [Copyright &y& Elsevier]

Abstract: FeMo/SiO2 catalysts were prepared by co-precipitation, sol–gel, or modified sol–gel (MSG) methods. These catalysts were characterized by N2 physisorption, H2 temperature-programmed reduction, X-ray diffraction, Mössbauer spectroscopy and transmission electron microscopy. Fischer–Tropsch synthesis (FTS) performances of catalysts were evaluated in a fixed-bed reactor at 300°C, 1.5MPa, 6nL/(g of catalyst·h) and H2/CO molar ratio of 2.0. The MSG-derived FeMo/SiO2 catalyst possessed higher surface catalytic sites, smaller iron crystallites, weaker Fe–SiO2 interaction and easier reduction behavior relative to conventional method derived catalysts. The modified catalyst also exhibited higher activity, lower methane selectivity and better stability in FTS reaction. [ABSTRACT FROM AUTHOR]

Highlights: [•] Effects of TiO2 on Co–Si interaction and electronic property of Co/SiO2 were studied. [•] A small amount of TiO2 weakened the interaction between Co and MCM-41 silica (MS). [•] The TiO2 improved electron density of cobalt species on 10Co/Ti–MS–X catalysts. [•] The TiO2 improved CO adsorption, while suppressed H2 adsorption at high Ti loading. [•] High FTS activity and heavy hydrocarbons selectivity were shown on 10Co/Ti–SiO2–10/100. [Copyright &y& Elsevier]