Analysis and Parametric Study of Reinforced Concrete Two-Way Ribbed Slabs by using ANSYS

This paper presents the results of finite element analysis for two experimental works (taken from other research works). The aim of this study is to use finite element method (FEM) by using ANSYS (v.15) software to analyse the specimens of experimental work to verify the validity of FEM by comparison with experimental results. In addition, some parametric studies on these works are done to cover the effect of some important variables on the ultimate load capacity and deflection which were not covered in the experimental work. The results of ANSYS software for chosen examples shows good agreement with the experimental results. Load-deflection curves for ANSYS models are higher than the experimental curves. The average value of correlation factor is (98.85%)for first example and (73.7%) for the second one. Results have shown that the percentage of increase in stiffness increases with increasing of slab thickness, but this increase is governed by the spacing between ribs

Unimolecular decomposition reactions of propylamine and protonated propylamine

A detailed computational study of the decomposition reaction mechanisms of cis-propylamine (cis-PA), trans-propylamine (trans-PA), and the cis-isomer of its protonated form (cis-HPA) has been carried out. Fourteen major pathways with their kinetic and thermodynamic parameters are reported. All reported reactions have been located with a concerted transition state, leading to significant products that agree with previous theoretical and experimental studies. Among six decomposition pathways of trans-PA, the formation of propene and NH3 is the significant one, kinetically and thermodynamically, with an activation energy barrier of 281 kJ mol–1. The production of two carbenes is found via two different transition states, where the reactions are thermodynamically controlled and reversible. Furthermore, five decomposition pathways of cis-PA have been considered where the formation of ethene, methylimine, and H2 is the most plausible one with an activation energy barrier of 334 kJ mol–1. The results show that the formation of propene and NH4+ from the decomposition of cis-HPA is the most favorable reaction with an activation barrier of 184 kJ mol–1, that is, the lowest activation energy calculated for all decomposition pathways

Preparation of 3-(9-Anthryl)acrylates and 9-Aroylethenylanthracenes as Pi-Extended Anthracenes and Their Diels–Alder Type Adducts with Electron-Poor Dienophiles

<p>(E)<b>-</b>3-(9-Anthryl)acrylates and (E)-9-aroylethenylanthracenes have been prepared by solventless Wittig olefination with conjugated phosphoranes. The (E)-3-(9-anthryl)acrylates were brominated to give (E)-3[10-{9-bromoanthryl}]acrylates, which could be subjected to Suzuki reactions with arylboronic acids to produce (E)-3-[10-{9-arylanthryl}]acrylates as pi-extended systems. The compounds thus prepared were subjected to Diels–Alder reactions, partly under solventless conditions.</p