Prabhat Kumar College

About: Prabhat Kumar College is a based out in . It is known for research contribution in the topics: Schiff base & Scalar field. The organization has 39 authors who have published 109 publications receiving 574 citations.

First principles Raman study of boron and nitrogen doped planar T-graphene clusters

Abstract: Tetragonal graphene (TG) is one of the theoretically proposed dynamically stable graphene allotropes. In this study, the Raman spectra, IR spectra and some electronic properties of pristine and doped (single boron (B) and nitrogen (N)) TG have been investigated by first-principles based density functional theory (DFT) at the B3LYP/6-31G(d) level. Formation energy computation indicates that for the pristine structures, stability increases with increasing cluster size. In addition, for a particular cluster size, single B doping introduces some distortion in the system while single N doping increases the stability of it. The Raman spectrum of the N doped system is dominated by a single peak but for the B doped system several intense lines are found. For all the structures low intensity similar breathing-like modes have been observed. Besides, relatively low (high) intensity Raman lines are found for single B (N) doping compared to those of the pristine one. The vibrational study also reveals the existence of a prominent phonon Raman line for pristine clusters which hardly changes its position and nature of vibration with varying cluster size. So this mode can be used for identification of pristine TG structures. Unlike pristine TG, the doped structures possess non-zero finite dipole moments due to asymmetry in charge distribution. Large values of the HOMO–LUMO gap as well as the absence of DOS at the Fermi level lead to the semiconducting nature of all the structures. All these theoretical predictions from DFT calculations may shed light on experimental observations involving TG systems.

The Hawking temperature in the context of dark energy

Abstract: An emergent-gravity metric incorporating k-essence scalar fields ? having a Born-Infeld?type Lagrangian is mapped into a metric whose structure is similar to that of a blackhole of large mass M that has swallowed a global monopole. However, here the field is not that of a monopole but rather that of a k-essence scalar field. If ?emergent are the solutions of the emergent-gravity equations of motion under cosmological boundary conditions at ?, then for the rescaled field has exact correspondence with ? with ?(r,t)?=??1(r)?+??2(t). The Hawking temperature of this metric is , taking the speed of light c?=?1. Here is the kinetic energy of the k-essence field ? and K is always less than unity, kB is the Boltzmann constant. This is phenomenologically interesting in the context of Belgiorno et al.'s gravitational analogue experiment.

A multi-warehouse partial backlogging inventory model for deteriorating items under inflation when a delay in payment is permissible

Abstract: In this paper we develop a multi-item multi-warehouse inventory model for deteriorating items for m secondary warehouses (SWs) and one primary warehouse (PW) with displayed stock and price dependent demand under permissible delay in payment. Items are sold from PW which is located at the main market and due to large stock and insufficient space of existing PW, excess items are stored at m SWs of finite capacity. Due to different preserving facilities and storage environment, inventory holding cost is considered to be different in different warehouses. Here the demand of items is a deterministic function of corresponding selling price and the displayed inventory. Shortages are allowed and partially backlogged. The items of SWs are transported to the PW in continuous release pattern and associated transportation cost is proportional to the distance from PW to SWs. Here $$M_{i} (

Adaptable sensor for employing fluorometric detection of methanol molecules: theoretical aspects and DNA binding studies

Abstract: The multifunctional Schiff base ligand N,N′-bis(5-nitro-salicylaldehyde)azine (NO2-H2SALNN) has been successfully synthesized and characterized by ESI-MS+, 1H-NMR spectroscopy and CHN elemental analysis. The very feeble intrinsic fluorescence exerted by the ligand was found to be enhanced by several folds in the presence of methanol (∼168 fold) and water (∼10 fold) molecules. This enhancement of fluorescence intensity is supposed to occur as a result of blocking of rotational isomerization along the azomethine group (CN) due to its coordination with solvent molecules, thereby causing turn on fluorescence at two distinct wavelengths in the presence of methanol and water having a large difference between the two emission wavelengths (Δλ = 125 nm). The hydrogen bond-assisted enhancement fluorescence (HAEF) for methanol and water at two different wavelengths giving two different emissions may be due to the different size/nature of the solvents as well as differences in solvent polarity. The binding of NO2-H2SALNN and the solvent molecules was investigated and described by spectroscopic and computational studies. The bioactivity of NO2-H2SALNN has also been inspected by DNA binding measurements through spectrometric and thermodynamic studies. DNA binding studies reveal that the ligand interacts with double stranded CT-DNA through a groove binding mode and the intrinsic binding constant was determined by calorimetric studies to be (2.24 ± 0.04) × 105 M−1.