A family of ambient-dried polybenzoxazine aerogels is prepared with a facile and scalable process as a high-performance polymeric aerogel with strong and robust thermomechanical properties at elevated temperatures. Those materials are inherently flame-retardant and superhydrophobic over the entire bulk density range (0.24–0.46 g cm–3). In addition, they are mechanically strong with strengths (e.g., 1 MPa at 0.24 g cm–3 at room temperature) higher than those of other high-performance aerogels of similar density, including polyimide and polyamide (Kevlar-like) aerogels as well as polymer-cross-linked X-silica and X-vanadia aerogels, at a significantly lower cost. Furthermore, unlike most other glassy polymeric materials, the maximum strength of the synthesized aerogels occurs at service temperatures slightly higher than room temperature (about 50 °C), which eliminates the possibility of any drop in strength with respect to the room temperature strength up to 150 °C at all densities. At higher temperatures (up to 250 °C), the overall performance of those aerogels is also stable and robust without any significant drop in Young’s modulus or strength levels, which makes them suitable for various industrial applications including high-performance structural and thermal protection applications as an alternative to the significantly more expensive polyimides.

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The simulations of fluid dynamics in a float glass furnace are performed by using the FLOTRAN module of ANSYS software. The velocity, turbulent kinetic energy, and density distribution of the fluids are determined. Three flowing cycle modes of the fluids are revealed, and this accounts for the heterogeneity in the glasses solidified from the fluids flowing out of the furnace. The simulation results are evaluated with the experimental measurements obtained via the side stripe image technique. The comparison of the simulation and experimental results reveals remarkable consistency.

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Atmospheric Pressure Plasma Jet (APPJ) has many applications in material processing such as surface modification and biomedical material processing. APPJ has been generated by a high voltage power supply (0-20 KV) at an operating frequency of (20-30) 23 kHz. This paper reports the generation and characterization of APPJ in Argon environment and its application in the surface modification of polymeric materials. The discharge has been characterized by optical and electrical methods. In order to characterize the plasma jet, its electron temperature and electron density has been determined by optical emissions spectroscopy. The surface properties of the untreated and plasma treated Polyamide (PA) samples were characterized by contact angle measurement and surface energy analysis. BIBECHANA 17 (2020) 133-138

Simulations of the fluid dynamics of daily quantity of outflow from different locations (flowing cycles) in a float glass furnace were performed using a FLOTRAN module in ANSYS software. Simulation results were compared with experimental data obtained from side stripe images of the produced glass ribbon. Results showed that, with increased daily melting quantities, the daily quantity of outflow through the furnace outlet from cycle I and cycle III increased, but the daily quantity of outflow from cycle II decreased. The comparison of the simulation and the experimental results reveals remarkable consistency.

Fluid dynamic simulations within a float glass furnace model with a variable siege height were performed by using the FLOTRAN module within an ANSYS software package. Steady circulatory patterns of glass fluid are established and identified in various regions of the furnace, and corresponding daily flow rates within the furnace were calculated. By increasing the siege height, the region of bottom backward flow was found to have decreased at the waist and working chamber. For a typical siege height of 0.3 m, the furnace required 5.39 × 1010 J/day less energy to reheat the glass fluids, as compared with a traditional siege height.