Bo Chen¹, Bo Liu^2,*, Yong Chao³, Chao Zhong¹

Journal of Renewable Materials, Vol.10, No.12, pp. 3491-3504, 2022, DOI:10.32604/jrm.2022.021302

Abstract The formation process of aromatic hydrocarbon tar during the pyrolysis process of biomass components of cellulose and lignin was carried out by quantum chemical calculation based on density functional theory method B3LYP/6-31G++(d, p). 5-Hydroxymethylfurfural was chosen as the model compound of cellulose and hemicellulose, and syringaldehyde was chosen as the model compound of lignin. The calculation results show that the formation process of cellulose monocyclic aromatic hydrocarbon tar is the conversion process of benzene ring from furan ring, and the highest reaction energy barrier appears in the process of decarbonylation, which is 370.8 kJ/mol. The formation of lignin monocyclic aromatic… More >

Muhammad Imran^1,*, Ali Ahmad², Muhammad Azeem³, Kashif Elahi⁴

CMC-Computers, Materials & Continua, Vol.71, No.1, pp. 2053-2071, 2022, DOI:10.32604/cmc.2022.022064

Abstract Silica has three major varieties of crystalline. Quartz is the main and abundant ingredient in the crust of our earth. While other varieties are formed by the heating of quartz. Silica quartz is a rich chemical structure containing enormous properties. Any chemical network or structure can be transformed into a graph, where atoms become vertices and the bonds are converted to edges, between vertices. This makes a complex network easy to visualize to work on it. There are many concepts to work on chemical structures in terms of graph theory but the resolvability parameters of a graph are quite advance… More >