Complexation of ligand?5 answersComplexation of ligands plays a crucial role in various processes such as wastewater treatment, metal extraction, and stabilization of metal clusters. Different ligands exhibit varying complexation behaviors with metals, impacting processes like ammonia removal, selective extraction of lanthanides over actinides, and stabilization of metal clusters like Cu, Ag, and Au. Techniques like FT-IR, NMR spectroscopy, UV-vis, and fluorescence spectrophotometry are utilized to study complexation mechanisms. The thermodynamics, stability constants, and bonding nature of metal-ligand complexes are investigated to understand the complexation process better. Additionally, studies using mass spectrometry reveal how the electrospray process can accelerate the formation kinetics of metal-ligand complexes, influencing solution equilibria. Overall, complexation of ligands with metals is a diverse and intricate field with significant implications across various scientific disciplines.
How to synthesize Schiff base metal complexes?4 answersSchiff base metal complexes can be synthesized by condensing primary amines with aldehydes or ketones to form Schiff bases (SBs). These SBs can then be utilized to form mononuclear or dinuclear metal complexes by reacting them with metal salts in specific ratios. For instance, Co(II) and Cr(III) metal complexes of Schiff bases were synthesized by condensing specific substrates and investigating their structures through various spectroscopic techniques. Additionally, the synthesis of metal complexes using Schiff base ligands was demonstrated by the condensation of different substrates to form ligands that can bind to metal ions, leading to the formation of various metal complexes with distinct geometries and properties. Furthermore, the synthesis and characterization of Cu(II), Ni(II), Co(II), and Fe(III) complexes of Schiff bases were achieved through a series of analytical and spectroscopic methods.
What is the method of anti tyrosinase study on skin animal, using topical preparation?4 answersThe method of anti-tyrosinase study on skin animals using topical preparation involves the use of various compounds and techniques. One method involves combining a metal chelate compound with a human manganese SOD or an ascorbic acid compound to inhibit tyrosinase activity. Another method utilizes a transdermal tyrosinase inhibitor prepared by synthesizing zinc oxide quantum dots and connecting them with BQ-788 to form BQ-788/NH2@ZnO. Additionally, theaflavin, a compound extracted from black tea, has been found to inhibit tyrosinase activity and hinder melanin synthesis in zebrafish. Furthermore, an oxime ether group-containing hydroxypyridone derivative has been developed as a tyrosinase inhibitor. Lastly, a tyrosinase inhibitor has been prepared using radix puerariae and saffron extracts, which effectively inhibits tyrosinase activity without side effects.
What is the cristalline structure of Sb2Se3?3 answersThe crystalline structure of Sb2Se3 is Pnma.
What are the similarities and differences between arsenic, bismuth, and antimony?3 answersArsenic, bismuth, and antimony are elements that belong to Group V of the Periodic Table. They have similar properties and have been used for various purposes in medicine, pest control, and the production of semiconductors. Arsenic and antimony exhibit chemistry that is different from their lighter congeners due to their larger radii, high polarizability, and low electronegativity. Arsenic, antimony, and bismuth can coexist in arsenic-bearing materials, making their separation difficult. The chemistry of these elements has been extensively studied, including their synthesis, structural investigations, and chemical reactivity. Arsenic has been used in the treatment of clinical illnesses and as a dopant in semiconductors. Antimony compounds have been used as drugs in treating parasitic diseases. Bismuth is a brittle metal with unique physical properties and is found in nature associated with sulfide ores. The toxicological significance of bismuth and its compounds is still unknown.
What is the crystalline structure of antimony selenide?1 answersAntimony selenide (Sb2Se3) has an indirect energy band gap of 1.21 eV, with a possible direct transition only 0.01 eV higher than the band gap (1.22 eV). The crystalline structure of antimony-doped In2Se3, which is isostructural with In1.9As0.1Se3, is orthorhombic with unit cell parameters a = 3.97(1) A and c = 18.87(1) A. InSbSe3, on the other hand, has an orthorhombic structure with unit cell parameters a = 9.43(1) A, b = 14.02(5) A, and c = 3.96(1) A. The room temperature dc resistivity for In1.8Sb0.2Se3 is 4.4 × 104 Ω-cm, while that of InSbSe3 is 15.2(1) Ω-cm. Optical studies indicate that In1.8Sb0.2Se3 is an n-type semiconductor with a band gap of 1.1 eV, while InSbSe3 is a p-type semiconductor with a band gap of 0.92 eV.