Studies on Piparwar Open Cast Mines of North Karanpura Coalfield

This paper deals with the study on coal deposits of Piperwar block of north Karanpura coalfield. A detailed geological map with its geological features in relation to the exposed rock has been prepared. The litholog of borehole up to a depth of 67 m is prepared to observe the geological characteristics and the decomposition of coal seams. The coal deposits with a view to find out its grade, quality and reserves have been studied and a general data about the environmental condition of desolation of sediments and deposition of coal has been presented. The structural units and where ever interesting features observed are photographed. The rank and grade of coal is interpreted based on the present study. However, more boreholes in the unexplored areas of the coalfield are required for the preparation of an elaborated geological map

Fenton’s Reagent Catalyzed Release of Carbon Monooxide from 1,3-Dihydroxy Acetone

Triose sugar, 1,3-dihydroxy acetone (DHA) on treatment with Fenton’s reagent releases CO under physiological conditions. The release of CO has been demonstrated by myoglobin assay and quantum chemical studies. The mechanistic study has been carried out using B3LYP/6-311++G­(d,p), M06-2X/6-311++G­(d,p) and CCSD­(T)//M06-2X/6-311++G­(d,p) level of theories in aqueous medium with dielectric constant of 78.39 by employing the polarized continuum model (PCM). The theoretical investigation shows that DHA breaks down completely into 2 equiv of CO, 1 equiv of CO₂, and 6 equiv of H₂O without formation of toxic metabolites. The activation barriers of some steps are as high as ∼50 kcal mol^–1 along with barrierless intermediate steps resulting from highly stabilized intermediates. The quantum tunneling mechanism of proton transfer steps has been confirmed through kinetic isotope effect study. The natural bond orbital analysis is consistent with the proposed mechanism. The present protocol does not require any photoactivation and thus it can serve as a promising alternative to transition metal CO-releasing molecules. The present work can initiate the study of carbohydrates as CO-releasing molecules for therapeutic applications and it could also be useful in generation of CO for laboratory applications

Theoretical Investigation of Photomagnetic Properties of Oxoverdazyl-Substituted Pyrenes

We have investigated the ground state spin of 10 pairs of possible photochromic diradical isomers by quantum chemical methods. Dihydrogen pyrenes and dinitrile pyrenes have been chosen as spacers with radical centers attached at (1,7) and (1,8) locations. Oxoverdazyl has served as a radical center, and both C and N linkages have been investigated. Triplet molecular geometries have been optimized at the UB3LYP/6-311G­(d,p) level. Single-point calculations on triplet and broken symmetry states have been performed using the 6-311++G­(d,p) basis set. Careful designs have led to the prediction of strongly coupled dihydropyrene (DHP) isomers, and the cyclophenadiene (CPD) isomers have always been found as weakly coupled. The effect of the functional M06-2X has been investigated. Calculated TDDFT spectra have been sufficient to guarantee photochromism of the designed diradicals. It has been estimated that compounds of diradicals with large coupling constants in the DHP form would show a pronounced change in molar susceptibility on photoconversion. This has led us to identify two molecules that can serve as a photomagnetic switch at room temperature

Ligand Chirality Transfer from Solution State to the Crystalline Self‐Assemblies in Circularly Polarized Luminescence (CPL) Active Lanthanide Systems

The synthesis of a family of chiral and enantiomerically pure pyridyl‐diamide (pda) ligands that upon complexation with europium [Eu(CF3SO3)3] result in chiral complexes with metal centered luminescence is reported; the sets of enantiomers giving rise to both circular dichroism (CD) and circularly polarized luminescence (CPL) signatures. The solid‐state structures of these chiral metallosupramolecular systems are determined using X‐ray diffraction showing that the ligand chirality is transferred from solution to the solid state. This optically favorable helical packing arrangement is confirmed by recording the CPL spectra from the crystalline assembly by using steady state and enantioselective differential chiral contrast (EDCC) CPL Laser Scanning Confocal Microscopy (CPL‐LSCM) where the two enantiomers can be clearly distinguished