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• H 2 injection can enhance methane conversion in fluidized beds by a factor of 3. • Methane conversion is affected by the open area ratio and hole size of the baffle. • The thermal uniformity can be controlled by the open area ratio of the baffle. Methane combustion in fluidized beds is inefficient at bed temperatures of 750 °C or lower, because the ignition delay of methane increases under such conditions. Owing to this, tail-off gases such as methane find limited use as fuel in fluidized beds, such as regenerators of light-naphtha fluid catalytic cracking. In this study, methane combustion in a fluidized bed with a light-naphtha cracking catalyst was investigated to enhance methane conversion using a baffle and H 2 injection as an ignition source. Two design parameters, the open area ratio and hole size of the baffle, were evaluated to determine their effects on methane conversion and thermal uniformity in the fluidized bed. In addition, it was confirmed that the use of a baffle and H 2 injection enhances methane conversion by a factor of three, compared to that without H 2 injection. [ABSTRACT FROM AUTHOR]

Temperature gradient interaction chromatography (TGIC) was applied for the separation of a complex miktoarm star copolymer which has one polystyrene (PS) arm and three polystyrene-b-polyisoprene (PS-b-PI) diblock copolymer arms. Such miktoarm star polymers are much more difficult to characterize than branched homopolymers since the byproduct, typically polymers with missing arm(s) or coupled products, have not only different molecular weights but also different compositions. TGIC was able to fully separate the byproducts, and the composition of the molecular species corresponding to the different separated elution peaks was determined by two methods, fractionation/NMR and multiple detection (UV and RI). A reasonable agreement between the results of the two methods was obtained. By using the composition found, the corresponding molecular weights were determined by multi-angle light scattering detection. Based on the composition and the molecular weight we were able to identify the structure of the different molecular species. [Copyright &y& Elsevier]

• Methane combustion in fluidized beds with inert particles was investigated. • Methane conversion with H2 injection in fluidized beds is 4 times that without H2. • Temperature for complete methane combustion is reduced by injecting H2. The characteristics of methane combustion were investigated in a fluidized bed reactor containing inert SiO 2 particles in the temperature range 700–800 °C. In particular, the methane was combusted using H 2 injection as an ignition source to initiate combustion at the relatively low temperature of 700 °C. It was found that complete combustion can be achieved at a bed temperature above 870 °C without ignition and at 800 °C with ignition. Even though the fast gaseous combustion of methane was initiated by ignition, the fast chain reaction was quenched under the condition of a bed temperature of less than 800 °C and insufficient residence time compared with the ignition delay at a given bed temperature. Moreover, it was confirmed that whereas NO x emission is reduced by decreasing the combustion temperature, the CO concentration of the exhaust gases increases drastically. [ABSTRACT FROM AUTHOR]

Salinization of land is globally increasing due to climate change, and salinity stress is an important abiotic stressor that adversely affects agricultural productivity. In this study, we assessed a halotolerant endophytic bacterium, Pseudoxanthomonas sp. JBR18, for its potential as a plant growth-promoting agent with multiple beneficial properties. The strain exhibited tolerance to sodium chloride concentration of up to 7.5 % in the R2A medium. In vitro evaluation revealed that strain JBR18 possessed proteolytic, protease (EC 3.4), and cellulase (EC 3.2.1.4) activities, as well as the ability to produce indole-acetic acid, proline, and exopolysaccharides. Compared with the controls, co-cultivation of Arabidopsis seedlings with the strain JBR18 improved plant growth, rosette size, shoot and root fresh weight, and chlorophyll content under salinity stress. Moreover, JBR18-inoculated seedlings showed lower levels of malondialdehyde, reactive oxygen species, and Na+ uptake into plant cells under salt stress but higher levels of K+. Additionally, seedlings inoculated with JBR18 exhibited a delayed response time and quantity of salt-responsive genes RD29A , RD29B , RD20 , RD22 , and KIN1 under salt stress. These multiple effects suggest that Pseudoxanthomonas sp. JBR18 is a promising candidate for mitigating the negative impacts of salinity stress on plant growth. Our findings may assist in future efforts to develop eco-friendly strategies for managing abiotic stress and enhancing plant tolerance to salt stress. [Display omitted] • JBR18 significantly increased Arabidopsis biomass under salt and non-salt stress. • JBR18 inoculation stimulated indole-3-acetic acid production in Arabidopsis roots. • JBR18 decreased ROS leves and Na + ion uptake into plant cells under salt stress. • JBR18 reduced the salt stress response gene levels in Arabidopsis under salt stress. • JBR18 is a promising microbial agent that can mitigate the negative effects of salinity stress on plant growth. [ABSTRACT FROM AUTHOR]

Semifluorinated block copolymers of poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(fluorooctyl methacrylates) (PFOMA) were prepared using group transfer polymerisation via sequential monomer addition. Wide ranges of copolymers were obtained with good control over both molecular weight and composition by adjusting the monomers/initiator ratio. The micellar characteristics of the copolymers in water and chloroform were investigated by quasi-elastic light scattering and transmission electron microscopy. The size and morphologies of micelles were greatly influenced by copolymer composition, pH, and temperature. In addition, the solubility of copolymers and the formation of water-in-carbon dioxide (W/C) microemulsions were described in terms of the cloud points. The block copolymers exhibited the excellent ability of stabilizing W/C microemulsions. [Copyright &y& Elsevier]