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Strontium amidoborane, Sr(NH 2 BH 3 ) 2 , is synthesized by gently milling the powder mixtures of SrH 2 and ammonia borane (in a 1:2 molar ratio), followed by isothermally processing the postmilled mixtures at 45°C for 2 h. It is found that Sr(NH 2 BH 3 ) 2 crystallizes with a monoclinic structure in space group C2, with lattice parameters a ) 8.1660(4) Å, b ) 5.0969(3) Å, c ) 6.7258(4) Å, and ) 94.392(4)°, and with Z ) 2. In the structure, each Sr 2+ bonds with two [NH 2 BH 3 ] 2-ions with a Sr-N distance of 2.68 Å. Thermal analyses show that the decomposition of Sr(NH 2 BH 3 ) 2 into Sr(NBH) 2 and H 2 initiates at about 60°C and becomes violent as the temperature increases to 93°C in the heating process at a rate of 2°C min -1 . With the release of H 2 , a considerable amount of NH 3 and small amounts of B 2 H 6 are also emitted due to the decomposition of Sr(NBH) 2 .

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The ultrasound-assisted extraction process of phenolics including anthocyanins from wine lees was modeled and optimized in this research. An ultrasound bath system with the frequency of 40 kHz was used and the acoustic energy density during extraction was identified to 48 W/L. The effects of extraction time, extraction temperature, solvent-to-solid ratio and the solvent composition on the extraction yields of total phenolics and total anthocyanins were taken into account. The extraction process was simulated and optimized by means of artificial neural network (ANN) and genetic algorithm (GA). The constructed ANN models were accurate to predict the extraction yields of both total phenolics and total anthocyanins according to the statistical analysis. Meanwhile, the input space of the ANN models was optimized by GA, so as to maximize the extraction yields. Under the optimal conditions, the experimental yields of total phenolics and total anthocyanins were 58.76 and 6.69 mg/g, respectively, which agreed with the predicted values. Furthermore, more amounts of total phenolics and total anthocyanins were extracted by ultrasound at the optimal conditions than by conventional maceration. On the other hand, the stability of phenolics in the liquid extracts obtained from ultrasound-assisted extraction during storage was evaluated. After 30-day storage, the total phenolic contents in extracts stored at 4 °C and 20 °C decreased by 12.5% and 12.1%, respectively. Moreover, anthocyanins were more stable at 4 °C while tartaric esters and flavonols exhibited a better stability at 20 °C. Overall, the loss of phenolics during storage found in this study could be acceptable.

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Mitigation of soot emissions from combustion devices is a global concern. For example, recent EURO 6 regulations for vehicles have placed stringent limits on soot emissions. In order to allow design engineers to achieve the goal of reduced soot emissions, they must have the tools to so. Due to the complex nature of soot formation, which includes growth and oxidation, detailed numerical models are required to gain fundamental insights into the mechanisms of soot formation. A detailed description of the CoFlame FORTRAN code which models sooting laminar coflow diffusion flames is given. The code solves axial and radial velocity, temperature, species conservation, and soot aggregate and primary particle number density equations. The sectional particle dynamics model includes nucleation, PAH condensation and HACA surface growth, surface oxidation, coagulation, fragmentation, particle diffusion, and thermophoresis. The code utilizes a distributed memory parallelization scheme with strip-domain decomposition. The public release of the CoFlame code, which has been refined in terms of coding structure, to the research community accompanies this paper. CoFlame is validated against experimental data for reattachment length in an axi-symmetric pipe with a sudden expansion, and ethylene-air and methane-air diffusion flames for multiple soot morphological parameters and gas-phase species. Finally, the parallel performance and computational costs of the code is investigated.

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