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This study presents density functional theory based computational analysis of geopolymeric materials of varied Si:Al ratios and extra‐framework cations. Due to the absence of crystallinity and long‐range order in geopolymers, no standard molecular models are present for quantum chemical analysis of these materials. Therefore, computationally feasible molecular models conforming to experimental reports and constraints are developed that accounted for all combinatorially possible local structures in the material. The computational analysis conclusively proved the effect of Si:Al ratio and the identity of the extra‐framework cation on the stability of the material with Si:Al = 2:1 decorated with Ca2 + ions exhibiting the highest stability. No significant effect of local structure is observed on the stability of the systems. Insights into the stability and adsorption property are developed on the basis of partial charge distribution thereby providing the details on the effects of constituent elements on the structure‐property relationships in geopolymers. [ABSTRACT FROM AUTHOR]

• CuO loaded mesoporous geopolymer was synthesised. • The catalytic activity of the synthesised compound was tested for the oxidation of aldehydes to carboxylic acids. • The synthesised catalyst was observed to be active, stable and recyclable for the reaction. • DFT calculations were carried out to probe the details on the catalytic chemistry. • Mechanistic details along with the associated energetics were developed. This article focuses on the synthesis of copper (II) oxide impregnated mesoporous geopolymer (CuO/Geo) catalyst and its catalytic activity for the oxidation of aldehydes to the corresponding carboxylic acids. CuO/Geo was synthesised by a two-step method. Mesoporous geopolymer was prepared which was used as a support for CuO through incipient wetness method. The synthesized catalyst was characterized using FE-SEM, FT-IR, BET surface area, XRD and XPS. For the oxidation reaction, water was used as the solvent and oxygen as the sole oxidant. On the basis of the experimental observations, CuO/Geo was found to be a good catalyst with 67% conversion of benzaldehyde to benzoic acid, observed in 10 h at 80 °C. It was established from XPS analysis that the oxidation reaction took place via Cu2+/Cu+/Cu2+ transformations. Density functional theory calculations provided insights into the adsorption energetics and the reaction mechanism. The mechanism for benzaldehyde oxidation was developed and the rate determining step was identified. The product formation step was observed to be the rate determining step with the free energy barrier of 59.6 kcal/mol. [Display omitted] [ABSTRACT FROM AUTHOR]

Analysis of protein thermostability is vital in protein science to aid the understanding of evolutionary aspects of organic life as well as in protein engineering for modern day industrial applications. In the present study, supervised machine learning (ML) algorithms are employed to unravel potential patterns behind protein thermostability. This computational analysis conclusively shows inverse gamma turns, VIII turns, and the propensity of cysteine (Cys) to be the most important biophysical–biochemical attributes responsible for protein thermostability. From the propensity analysis of amino acids, polar residues, specifically glutamine (Gln) and serine (Ser), and charged residues, specifically glutamic acid (Glu) and lysine (Lys), are found to favor the enhancement of protein thermostability. The study demonstrates the feasibility of assigning quantifiable descriptors of thermostability which is expected to aid protein engineering. [ABSTRACT FROM AUTHOR]