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- Author or Editor: Xiaojun Chen x
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Abstract
New indicators, including the outgrow index, characterizing an article in its ego citation network are introduced. We take full advantage of the existing duality (cites–is cited by) in a citation network. Although algebraic aspects are emphasized, a first step towards their interpretation is attempted. Examples of their calculation and of future applications are provided.
Abstract
Brookite titania nanomaterials modified with gold nanoparticles (NPs) Au–TiO2 were prepared in this research. The photocatalytic activity of the prepared composite was assessed by the photodegradation of organic pollutants. Rhodamine blue was used as a model organic pollutant. The study determined the optimum loading ratio of Au/Ti, which will result in the best photodegradation efficiency. Also, the photocatalytic activity of gold loaded brookite titania nanomaterials was ascertained under visible light. The hydrothermal method was used to prepare brookite titania whiles, gold NPs were loaded on its surface by consecutive ion adsorption and photoreduction. The results revealed that the sample Au–TiO2 (Au/Ti = 2 % molar ratio) had the best photocatalytic degradation efficiency of 100 % after 2 h of irradiation under visible light and was also higher than commercial P25.
Abstract
A simple, rapid, and sensitive method based on UPLC-MS/MS was developed to determine spiraeoside in mouse blood, and was applied to the pharmacokinetics and bioavailability of spiraeoside after mice after intravenous (a dose of 5 mg kg−1) and oral (a dose of 20 mg kg−1) administration. On HSS T3 column set at 40 °C, chromatographic separation was obtained with the mobile phase of acetonitrile and 0.1% formic acid using the gradient elution. Spiraeoside and internal standard (IS) were quantitatively analyzed using multiple reaction monitoring (MRM) mode in electrospray (ESI) positive interface. The MRM mode was monitoring the fragmentation of m/z 465.4→303.1 and m/z 451.3→ 289.2 for spironoside and IS, respectively. The results showed a good linear relationship was in the concentration range of 1–200 ng mL−1 (r > 0.998) and the lower limit of quantification (LLOQ) was 1.0 ng mL−1. The intra- and the inter-day precision (RSD%) of the method was within 14.0%, and the accuracy ranged from 90.0% to 115.0%. The extraction recovery of spriaeoside was better than 63.0%, and the matrix effects were in the range of 86%–98%. It also showed the half-life was short, and the absolute bioavailability was 4.0% in mice. Therefore, the established UPLC-MS/MS method was suitable for the pharmacokinetic and bioavailability study of spiraeoside in mice.
Abstract
Polyether-urethane samples were irradiated at the dose range from 10 to 2000 kGy by 2 MeV electron beams. Volatile species from the polymer degradation were analyzed quantitatively and qualitatively with GC/MS. Thermal properties and micro-phase separation of the samples were examined by TG and the morphology was studied by TEM and SEM. The results show that the irradiated polyether-polyurethane evolves CO2, H2, CH4 and C2H6, etc. The thermal stabilities between the hard and soft segments in the irradiated samples are different. At high doses, the phase separation in the sample is predominant and the hard segment of sample is more stable. The dose rate affects the soft segment of the irradiated sample much more.
