Internal Pressure Carrying Capacity for Different Loading Modes of Filament-Wound Pipes from Glass Fiber-reinforced Epoxy Composites

Development of a low-cost filament-winding machine is initially described in this paper. The filament-winding machine was used to fabricate composite pipes and the materials used were woven glass fiber and epoxy resin. The pipes were tested under three loading modes, namely mode I (hoop pressure loading), mode II (biaxial pressure loading), and mode III (biaxial pressure with axial compressive loading). The results reveal that filament-wound composite pipes should be wound at 75° for hoop pressure loading (mode I), 55° for biaxial pressure loading (mode II), and 85° for biaxial pressure with axial compressive loading (mode III).     

Efficacy of novel organotin(IV) complexes on non-durable tropical wood against decay fungi

Interest in organotin(IV) compounds is increasing due to their interesting structural features and possession of biological activities. The objective of this study was to determine the efficacy of novel organotin(IV) complexes against Trametes versicolor and Gloeophyllum trabeum decay fungi. Soil block decay test was performed using T. versicolor and G. trabeum for 16 weeks. Ten 19 × 19 × 19 mm³ sized wood cubes of Alstonia scholaris, Macaranga triloba and Hevea brasiliensis were treated with three levels of concentration (0.1, 0.5 and 1 %) of monomethyltin(IV) (MMT) and monophenyltin(IV) (MPT) of monosubstituted organotin(IV) and dimethyltin(IV) (DMT), diphenyltin(IV) (DPT) and dibutyltin(IV) (DBT) of disubstituted organotin(IV) complexes with 2-acetylpyridine-N(4)-cyclohexyl thiosemicarbazone (APCT) ligand and their respective retention uptake was determined. The best protection against decay fungi was provided by dibutyltin(IV) complex followed by diphenyltin(IV), dimethyltin(IV), monophenyltin(IV) and monomethyltin(IV) complexes with mean weight loss ranging from 4 to 5, 5 to 7, 8 to 9, 10 to 11 and 14 to 19 percent, respectively while the weight loss of the untreated wood cubes varied from 51 to 65 %. Wood densities decreased with increased weight loss. Density reduction of monosubstituted organotin(IV) treated wood cubes was higher than disubstituted organotin(IV) treated wood cubes. Soil block test showed that selected organotin(IV) complexes are effective and among all of them dibutyltin(APCT) complex gave the best protection against the tested T. versicolor and G. trabeum decay fungi.     

Two-dimensional numerical modeling of combustion of Jordanian oil shale

A two-dimensional (2-D) modeling of the burning process of Jordanian oil shale in a circulating fluidized bed (CFB) burner was done in this study. The governing equations of continuity, momentum, energy, mass diffusion, and chemical combustion reactions kinetics were solved numerically using the finite volume method. The numerical solution was carried out using a high-resolution 2-D mesh to account for the solid and gaseous phases, k-ε turbulence, non-premixed combustion, and reacting CFD model with the same dimensions and materials of the experimental combustion burner used in this work. The temperature distribution and evolution of species were also computed.

Proximate and ultimate analyses were also performed to evaluate the air–fuel ratio and ash content. The required thermophysical properties, such as heating value, density, and porosity were obtained experimentally, while the activation energy was obtained from published literature.

It was found that the temperature contours of the combustion process showed that the adiabatic flame temperature was 1080 K in a vertical burner, while the obtained experimental results of maximum temperature at various locations of the burner in actual, non-adiabatic, non-stoichiometric combustion reached 950 K, showing good agreement with the model.     

Refocus attention span networks for handwriting line recognition

International Journal on Document Analysis and Recognition (IJDAR) - Recurrent neural networks have achieved outstanding recognition performance for handwriting identification despite the enormous...