Prediction of urban surface water quality scenarios using hybrid stacking ensembles machine learning model in Howrah Municipal Corporation, West Bengal.

In the pursuit of understanding surface water quality for sustainable urban management, we created a machine learning modeling framework that utilized Random Forest (RF), Cubist, Extreme Gradient Boosting (XGB), Multivariate Adaptive Regression Splines (MARS), Gradient Boosting Machine (GBM), Support Vector Machine (SVM), and their hybrid stacking ensemble RF (SE-RF), as well as stacking Cubist (SE-Cubist), to predict the distribution of water quality in the Howrah Municipal Corporation (HMC) area in West Bengal, India. Additionally, we employed the ReliefF and Shapley Additive exPlanations (SHAP) methods to elucidate the underlying factors driving water quality. We first estimated the water quality index (WQI) to model seven water quality parameters: total hardness (TH), pH, total dissolved solids (TDS), dissolved oxygen (DO), biochemical oxygen demand (BOD), calcium (Ca), magnesium (Mg).

Eliminating all bonds from the ground state gives rise to ionic bonding in high-spin states of heterodiatomics.

Understanding chemical bonding in second-row diatomics has been central to elucidating the basics of bonding itself. Bond strength and the number of bonds are the two factors that decide the reactivity of molecules. While bond strengths have been theoretically computed accurately and experimentally determined, the number of bonds is a more contentious issue, especially for complicated multi-reference systems like C.

The curious saga of dehydrogenation/hydrogenation for chemical hydrogen storage: a mechanistic perspective.

Hydrogen storage is an indispensable component of hydrogen-based fuel economy. Chemical hydrogen storage relies on the development of lightweight compounds which can deliver high weight percentage of H at moderate temperatures through dehydrogenation and can be recovered from the dehydrogenated mass by hydrogenation for reuse. In this feature article we primarily discuss the mechanistic underpinnings of the catalytic dehydrogenation of ammonia-borane, a potential candidate for hydrogen storage and the challenges associated with its regeneration from the dehydrogenated mass.

Comprehending the quadruple bonding conundrum in C from excited state potential energy curves.

The question of quadruple bonding in C has emerged as a hot button issue, with opinions sharply divided between the practitioners of Valence Bond (VB) and Molecular Orbital (MO) theory. Here, we have systematically studied the Potential Energy Curves (PECs) of low lying high spin sigma states of C, N, Be and HC[triple bond, length as m-dash]CH using several MO based techniques such as CASSCF, RASSCF and MRCI. The analyses of the PECs for the Σ (with 2 + 1 = 1, 3, 5, 7, 9) states of C and comparisons with those of relevant dimers and the respective wavefunctions were conducted.

Frustrated Lewis Acid-Base-Pair-Catalyzed Amine-Borane Dehydrogenation.

Metal-free catalysis by sterically encumbered Lewis Acid-Base pairs, popularly known as frustrated Lewis pairs (), is gaining importance by the day due to its promise of providing a greener alternative to transition-metal-based catalysis. One of the stumbling blocks in achieving catalytic dehydrogenation of amine-boranes is catalyst deactivation by the reaction product. Herein, we have theoretically investigated the routes of a dimethylxanthene-derived B,P--catalyzed dehydrogenation of dimethylamine-borane , a rare instance which avoids catalyst inhibition by the reaction product.

Pulmonary Function Studies of Healthy Non-smoking Male University Students of Kolkata, India - Revisited.

Background: Pulmonary function tests (PFTs) need to be revisited in light of rapid economic growth and industrial development. Questions have been raised about the validity of existing population-specific norms for predicting PFTs, and therefore, the present study aimed to determine the applicability of existing norms for PFTs in young healthy non-smoking male university students of Kolkata.

Methods: PFTs were carried out for 87 non-smoking male university students who were randomly sampled from the University of Calcutta, Kolkata, India.