Topological Indices of Some New Graph Operations and Their Possible Applications

A chemical graph theory is a fascinating branch of graph theory which has many applications related to chemistry. A topological index is a real number related to a graph, as its considered a structural invariant. It’s found that there is a strong correlation between the properties of chemical compounds and their topological indices. In this paper, we introduce some new graph operations for the first Zagreb index, second Zagreb index and forgotten index "F-index". Furthermore, it was found some possible applications on some new graph operations such as roperties of molecular graphs that resulted by alkanes or cyclic alkanes.

EXPERIMENTAL AND NUMERICAL STUDY OF COMBUSTION OF AVIATION KEROSENE TS-1 SURROGATES

The article analyzes two types of kerosene surrogates: six-component SU1 and four-component SU2. The characteristics of the both differ from the accepted reference values no more than by 1%. It is revealed that multicomponent surrogates are necessary for reproducing the physicochemical properties of the real aviation kerosene. In addition, various classes of hydrocarbons such as alkanes, cyclic alkanes, and aromatic hydrocarbons should be included in order to meet these properties. Other parameters such as density, H/C ratio, and molar mass impose additional and important constraints on the development of surrogates. Several methods for combined reactor prediction of the concentrations of carcinogenic polycyclic aromatic hydrocarbons (PAHs) in aircraft kerosene combustion chambers have been proposed and investigated.

FTIR Spectroscopic Study of Aloe vera barbadensis Mill Buds

The objective of this research is to investigate number and types of bioactive compounds present in Aloe Vera buds grown in North East Punjab region of Pakistan by FTIR which is simple, nondestructive, cost effective and user friendly. Aloe vera was cultivated under normal atmospheric conditions. After two years, buds (early stage of flowers) were grown on twigs. The buds were plucked and blended with distilled water in National Juicer machine to have a concentrated blend. The blend was filtered to get clear solution, mixed with ethyl acetate and then solvent extracted. The organic part was isolated and dried at water bath at 60°C. Dried sample was analyzed using FTIR spectroscopic analysis. All activities were performed consecutively to avoid photochemical changes. The characteristic FTIR spectral lines have shown different characteristic peaks that correspond to different functional groups indicating presence of bioactive compounds like substituted cyclic alkanes, alkenes, alcohols, phenols, and aromatics etc. have been investigated.

Correction: The conversion of a high concentration of lignin to cyclic alkanes by introducing Pt/HAP into a Ni/ASA catalyst

Correction for ‘The conversion of a high concentration of lignin to cyclic alkanes by introducing Pt/HAP into a Ni/ASA catalyst’ by Shufang Qin et al., Green Chem., 2020, 22, 2901–2908, DOI: 10.1039/D0GC00243G.

The conversion of a high concentration of lignin to cyclic alkanes by introducing Pt/HAP into a Ni/ASA catalyst

A novel strategy is demonstrated that enables the conversion of highly concentrated lignin to cyclic alkanes.

DFT study of triplet and singlet elementary acts of acyclic and cyclic alkanes oxidation initiated by primary interaction with 3O2

The primary oxidation stages of 3O2 model acyclic and cyclic alkanes and their subsequent triplet and singlet elementary events were studied for the first time by the DFT method with the density functional B3LYP and basis set 6-311++g(df,p). According to quantum chemical DFT calculations the C–H radical cleavage of the bonds of acyclic and cyclic alkanes upon interaction with 3O2 is almost completely thermodynamically shifted toward the initial state of the reaction system. This energy of primary oxidizing events explains the extremely low reactivity of saturated alkanes in comparison with asphaltene structural fragments under the conditions of SCF technology for the extraction of heavy oils and asphaltenes by a propane-butane mixture. It has been demonstrated that for all elementary acts of primary alkane oxidation the product of the direct reaction direction is not a free pair of radicals but a triplet hydrogen complex with a pronounced hydrogen bond between the hydroperoxyl radical and the radical form of the corresponding hydrocarbon. A new, previously not taken into account very exothermic (H = -29.25 – -30.77 kcal/mol) reaction direction is described which corresponds to triplet recombination of alkyl radicals and a hydroperoxyl radical in its oxygen-concentrated part. The products of this recombination are triplet forms of alkane hydroperoxides in which there is a fairly loosened triplet O---O bond with a length of 2.20-2.23 Å, which is ~0.72-0.77 Å more than bond length in the singlet state.

Production of renewable long-chained cycloalkanes from biomass-derived furfurals and cyclic ketones

Renewable cyclic alkanes were produced in high yield via condensation of biomass-based furfurals and cyclic ketones followed by hydrodeoxygenation.

Production of cyclopentanone from furfural over Ru/C with Al11.6PO23.7 and application in the synthesis of diesel range alkanes

Cyclopentanone as the substrate for the synthesis of jet fuel range cyclic alkanes can be prepared through the cyclopentenone route under mild conditions and catalyzed by Ru/C with Al11.6PO23.7 from furfural.