Synthesis of novel β-amino alcohols from phenylacetylcarbinol: cytotoxicity activity against A549 cells and molecular docking

Research on Chemical Intermediates - Synthesis of novel β-amino alcohols 7a–d and 9a–d have been disclosed by in situ formation of Schiff base from phenylacetylcarbinol 1 (PAC),...     

Crystal growth,spectral, thermal and optical properties of an organic single crystal – Dye doped hippuric acid

A new organic dye doped hippuric acid (DHA) single crystals have been grown from aqueous solution of acetone by doping with rhodamine using slow evaporation technique. Rhodamine is a dye, an organic molecule well-studied in laser physics and nonlinear optics for its fluorescent properties. Dyeing of crystals is a practice that was developed particularly for quantum optical applications because of the very significant increase in surface area achieved in growing crystals. In the present work, The DHA single crystals were successfully grown by the slow evaporation method. Good quality single crystals were harvested after 5 days. The grown crystal was characterized by various techniques namely Single crystal X-ray diffraction, FT-IR, UV–vis, NLO and thermal analysis. The FT-IR analysis confirms the presence of various functional groups available in DHA. The optical transmission study and Kurtz and Perry SHG measurement shows the suitability of doped crystals for NLO applications.     

Electromagnetic soliton propagation in an anisotropic Heisenberg helimagnet

We study the nonlinear spin dynamics of Heisenberg helimagnet under the effect of electromagnetic wave (EM) propagation. The basic dynamical equation of the spin evolution governed by Landau–Lifshitz equation resembles the director dynamics of the twist in a cholestric liquid crystal. With the use of reductive perturbation technique the perturbation is invoked for the spin magnetization and magnetic field components of the propagating electromagnetic wave. A steady-state solution is derived for the weakly nonlinear regime and for the next order, the components turn around s plane perpendicular to the propagation direction. It is found that as the electromagnetic wave propagates in the medium, both the magnetization and magnetic field modulate in the form of kink soliton modes by introducing amplitude fluctuation in the tail part of the same.     

Synthesis and Characterization of 5′-Hexyl-2,2′-bithiophene Based on Organic Dyes for Dye-Sensitized Solar Cell Applications

A series of new organic dyes, 2-(2,6-bis((E)-2-(5′-hexyl-2,2′-bithiophen-5-yl)vinyl)-pyran-4-ylidene)-2-cyanoacetic acid (OD-1) and 2,2′-(2-((E)-2-(5′-hexyl-2,2′-bithiophen-5-yl)vinyl)-1H-indene-1,3(2H)-diylidene)bis(2-cyanoacetic acid) (OD-2), were synthesized as a sensitizers for the application of dye-sensitized solar cells (DSSCs). The introduction of the 5′-hexyl-2,2′-bithiophene units as an electron donor group and 2,6-dimethyl-pyran-4-one or 1,3-indandione as a π-spacers units increased the conjugation length of the sensitizers and thus improved their molar absorption coefficient and light harvesting efficiency.     

Displacement Reaction Using Ibuprofen in a Mixture of Bioactive Imidazole Derivative and Bovine Serum Albumin—a Fluorescence Quenching Study

The mutual interaction of imidazole derivative (PIPP) with bovine serum albumin (BSA) was investigated using photoluminescent studies. The fluorescence quenching mechanism of BSA by PIPP was analyzed and the binding constant was calculated. The binding distance between PIPP and BSA was obtained based on the theory of Forester’s non-radiation energy transfer. Displacement experiments were performed by using ibuprofen to identify PIPP binding site in BSA. The effect of some common ions on the binding constant between PIPP and BSA was also examined.     

Iridium(III) Complexes with Orthometalated Phenylimidazole Ligands Subtle Turning of Emission to the Saturated Green Colour

A series of novel six iridium complexes (1–6) bearing two substituted phenylimidazole and an additional acetylacetone as the third co-auxilary ligand are reported. The lowest absorption band for all iridium complexes consist of a mixture of heavy atom Ir(III) enhanced ³MLCT and ³ π-π* transitions and the phosphorescent peak wavelength can be fine-tuned to cover the spectral range 455–518 nm with high quantum efficiencies. The peak wavelength of the dopants can be finely tuned depending upon the electronic properties of the substituents. On the basis of onset potentials of the oxidation and reduction, the HOMO-LUMO energies were calculated and the reported iridium complexes emit green light with exceeding higher efficiency.     

Synthesis of cobalt-doped cadmium sulphide nanocrystals and their optical and magnetic properties

Cobalt-doped cadmium sulphide (CdS) nanocrystals (NCs) were synthesized with three different cobalt concentrations by aqueous chemical coprecipitation method. Dopant incorporation was recognised using X-ray diffraction (XRD) analysis with a shift in the diffraction peaks and compression in the lattice. The size and crystallinity of the cobalt-doped CdS NCs were studied by high resolution transmission electron microscopy (HRTEM). The blue shift in the spectra and the band gap value of Co-doped CdS NCs was estimated using reflectance UV spectrophotometer. Variation in the luminescence properties was studied by fluorescence spectroscopy. The change in the optical properties supports the Co incorporation in the CdS NCs. The BET measurement revealed that the powders had a relatively high specific surface area of 131.30, 106.93 and 102.04 m²/g for 2, 4 and 6% Co:CdS, respectively. Room temperature magnetisation was studied using vibrating sample magnetometer for both 4 and 6% cobalt-doped CdS NCs, which revealed a weak ferromagnetic signal and strong ferromagnetic hysteresis respectively.     

Synthesis of 3,4-disubstituted 2,5-dihydrofurans starting from the Baylis-Hillman adducts via consecutive radical cyclization, halolactonization, and decarboxylation strategy

A facile synthetic method of 3,4-disubstituted 2,5-dihydrofurans and 2,5-dihydropyrroles starting from the Baylis-Hillman adducts was developed. The 2,5-dihydrofuran skeleton was constructed via the consecutive radical cyclization, hydrolysis, halolactonization, and spontaneous decarboxylation strategy starting from the modified Baylis-Hillman adducts.     

Jump-reduced immersed boundary method for compressible flow

The main challenge of the immersed boundary approach is the proper enforcement of boundary conditions on the body interface without any spurious oscillations, which are induced by the nongrid-conforming boundary configuration. In this study, a new sharp interface ghost-cell immersed boundary method (IBM) is proposed for obtaining solutions near the immersed boundary with a high order of accuracy. The main idea is “jump-reduction” instead of jump-correction across the boundary interface by combining the ghost-cell method with the flow reconstruction method. In the proposed IBM, the unknown values at the three points, that is, boundary points, ghost cell, and flow field reconstruction point are solved simultaneously using equations formulated by the moving least-squares interpolation method. It is a hybrid of ghost-cell and flow reconstruction methods, correlated with interface values, which result in a reduced jump-discontinuity. In addition, a discontinuity-distinguishing algorithm is introduced so that the low-order method is applied only to the discontinuous or non smooth region, while the current high-order method is applied elsewhere. Reduced jump-discontinuity of the proposed IBM has been verified in both subsonic and supersonic flow using fundamental benchmark problems. We observed that the reduced jump-discontinuity does not hamper the mass conservation and shows even better conservation property than conventional methods due to the nonoscillatory performance in smooth regions. The numerical results further confirm the ability of the proposed IBM to solve complex flow physics with high-order accuracy and improved stability.     

Preliminary measurements of natural radioactivity at Madurai district of Tamilnadu, India

In dwellings, the radon and their daughter products contribute the largest fraction to the doses received from natural background radiation. In the present study, the radon levels at Madurai district of Tamilnadu have been measured initially for 15 dwellings using cellulose nitrate (C₆H₈O₉N₂) LR-115 type II (non-pelliculable) films and the dose assessment due to radon and its daughter product concentrations is calculated. These results were intercompared with other terrains viz. Jodhpur district of Rajasthan which is considered as semi-desert terrain and Jammu district of Jammu & Kashmir which is the hilly area. Also the natural radioactivity in soil samples of Madurai have been measured using NaI(Tl) detector based gamma spectrometry. From these radioactivity levels, the radium equivalent activity is calculated and a correlation between this and radon concentration has been tried out.