Effect of Crystallinity of β- and βbc-Nickel Hydroxide Samples on Chemical Cycling

β-phases of nickel hydroxide and cobalt hydroxide samples crystallize in cadmium iodide type structure. β-cobalt hydroxide on oxidation generates β-CoOOH which crystallized in 3R1 polytype while the structure of β-phase of NiOOH polytype is less well understood. β- and βbc-phases of nickel hydroxide samples were prepared by using ammonium hydroxide and sodium hydroxide as precipitating agents. Powder X-ray diffraction data shows that β-phase of nickel hydroxide is perfectly crystalline in nature while βbc-phase of nickel hydroxide is poorly ordered. β- and βbc-phases of nickel hydroxide samples were subjected to chemical oxidation using sodium hypochlorite. The oxidized phases of β- and βbc-phases of nickel oxyhydroxide are highly disordered and the broadening of reflections in the powder X-ray diffraction patterns is due to the presence of structural disorder, variations in the crystallite size, and strain. On reduction of β- and βbc-phases of nickel oxyhydroxide, the powder X-ray diffraction patterns visually match the powder X-ray diffraction data of the pristine phases of β- and βbc-phases of nickel hydroxide indicating that the β-phase of nickel hydroxide does not transform to βbc-phase of nickel hydroxide, but the particle sizes are significantly affected

Binding Ability Studies of Arginine, Citrulline, N-Acetyl Citrulline and Thiocitrulline with SARS Cov-2 Main Protease Using Molecular Docking Studies

To Editor in Chief Chemarxiv Respected Sir/Madam Subject: submission of preprint of an article to ChemRxiv on molecular docking studies of arginine and its structural analogues on COV-19 for publication. I am herewith submitting the preprint of an article entitled “Binding ability studies of arginine, citrulline, N-acetyl citrulline and thiocitrulline with SARS Cov-2 main protease using molecular docking studies.” for publication as preprint in “ChemRxiv”. In this paper the binding abilities of arginine, citrulline, N-acetyl citrulline and thiocitrulline with SARS-COV-2 protease have been examined using molecular docking studies. The ligands used for docking has moderate binding affinity to active sites of main protease in terms of values. The binding affinities of these ligands are in the range of -3.1 to -5.1 kcal mol-1. All the ligands bind selectively to Cys-145 and also to other amino acids surrounding to it in the main protease. Of which arginine forms less number of weaker bonds compared to the other ligands, it by itself is a precursor for the formation of citrulline analogues with in the cell. Major advantage of using the above ligands is that in addition to its preferential binding these molecules also have the ability to enhance the immunity of the cells by the generation of nitric oxide in presence of enzymes thereby protecting them. Our results show that N-acetyl citrulline, citrulline, thiocitrulline and arginine may be used as a supplement during the treatment of SARS-COV-2. I request your good self to kindly accept the article and get it published as pre-print in your esteemed ChemRxiv. Thanking you With regards Ramesh T N ([email protected])</p

Calcium hydroxide as low cost adsorbent for the effective removal of indigo carmine dye in water

Adsorption of indigo carmine dye onto calcium hydroxide was investigated in this work. The variation in the pH, adsorbent dose, dye concentration, duration and the temperature was evaluated. Adsorption of indigo carmine dye onto calcium hydroxide was effective at pH 12 (50 min) and follows Langmuir-type isotherm behaviour. The adsorption process follows pseudo-second order rate kinetics. Enthalpy, entropy, free energy and the activation energy parameters have been reported

Structure and morphological studies of curcuminoids and curcuminoid mixture

Turmeric and commercial curcumin contains curcumin, desmethoxycurcumin and bisdesmethoxycurcumin as major components and they exhibit potential biological applications. Controlled crystallization of curcuminioids could lead to formation of new polymorphs/with different morphological features. In this report the structure and morphological changes taking place during the crystallization of curcuminoid mixture as well as individual curcuminoid polymorphs at different temperatures have been reported. The samples have been characterized using powder X-ray diffraction, infrared spectroscopy, H-1 and C-13 NMR and scanning electron microscopy. Our results show that curcumin exhibit polymorphs of which curcumin form 1 (monoclinic crystal system) has rod like morphology while curcumin form 2 (orthorhombic crystal system) shows sheet like morphology. Desmethoxycurcumin and bisdesmethoxycurcumin does not exhibit polymorphism and possess spherical shape and irregular morphology respectively