MCM-41-nPrNH2 as a Recoverable Nanocatalyst for the Synthesis of New Phenylpyrido[4,3-d]pyrimidin-2-amine Derivatives

MCM-41 anchored n-propylamine (MCM-41-nPrNH2) was found to be a highly efficient and recoverable nanocatalyst for the synthesis of new class of phenylpyrido[4,3-d]pyrimidin-2-amine derivatives under solvent free conditions in high to quantitative yields. All the structures of title compounds 3a-j were elucidated by comprehensive 1H NMR, 13C NMR, IR and Mass spectra When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3500

Electro-catalytic Oxidation of Formaldehyde on Copper Electrode: a New Kinetics Model

Abstract Electro-catalytic oxidation of formaldehyde on copper electrode in 100 mM NaOH solution at different concentrations of formaldehyde was studied in the steady state polarization technique. The CV curve shows evidence for two processes occurring at the interface: one is associated with the formaldehyde electro-oxidation leading to formic acid formation on the surface and the other is assigned to the oxidation of formic acid that leads to CO 2 evolutions with low yield. Reaction orders for the faradic current on copper electrode have been determined as 0.21 for the higher and 0.76 for the lower concentration of formaldehyde. Reaction orders for CO 2 evolution during formaldehyde oxidation are 1.4 times higher in each case. Tafel slopes in the range of 140-160 mV are found. This signifies that the first reaction step involving the formation of adsorbed CO 2 is largely determining the overall reaction rate

Poly-dopamine-Beta-Cyclodextrin Modifi ed Glassy Carbon Electrode as a Sensor for the Voltammetric Detection of L-Tryptophan at Physiological pH

ABSTRACT The main purpose of this report was to develop application of poly-dopamine-beta-cyclodextrin modifi ed glassy carbon electrode (PDA-β-CD-GCE) towards electrooxidation and determination of L-Tryptophan (L-Trp) and also the evaluation its kinetic parameters. In continuation of our efforts to use PDA-β-CD-GCE for amino acids detection, our objective in the present work was to expand application of this sensor for the determination of L-Trp which is very sensitive

Ion-Transfer Voltammetric Behavior of Propranolol at Nanoscale Liquid-Liquid Interface Arrays

In this work, the ion-transfer voltammetric detection of the protonated β-blocker propranolol was explored at arrays of nanoscale interfaces between two immiscible electrolyte solutions (ITIES). Silicon nitride nanoporous membranes with 400 pores in a hexagonal arrangement, with either 50 or 17 nm radius pores, were used to form regular arrays of nanoITIES. It was found that the aqueous-to-organic ion-transfer current continuously increased steadily rather than reaching a limiting current plateau after the ion-transfer wave; the slope of this limiting current region was concentration dependent and associated with the high ion flux at the nanointerfaces. Electrochemical data were examined in terms of an independent nanointerface approach and an equivalent microdisc approach, supported by finite element simulation. In comparison to the larger interface configuration (50 nm radius), the array of 17 nm radius nanoITIES exhibited a 6.5-times higher current density for propranolol detection due to the enhanced ion flux arising from the convergent diffusion to smaller electrochemical interfaces. Both nanoITIES arrays achieved the equivalent limits of detection, 0.8 μM, using cyclic voltammetry. Additionally, the effect of scan rate on the charging and faradaic currents at these nanoITIES arrays, as well as their stability over time, was investigated. The results demonstrate that arrays of nanoscale liquid–liquid interfaces can be applied to study electrochemical drug transfer, and provide the basis for the development of miniaturized and integrated detection platforms for drug analysis

A review of novel methods for Diuron removal from aqueous environments

Runoff from intensive agriculture, which contains many sources of pollutants, including herbicides, for instance, Diuron, has threatened the environment and human health. The intrusion of these toxins into water sources poses a serious challenge to human society, and the rising release of these toxins has always been of concern to water researchers. The consequences of the release of these toxins into water sources are destructive and debilitating to human life. Today, the contamination of surface water and wastewater by pesticide residues, especially from agricultural activities and pesticide factories, has grown significantly. One of the pesticides commonly applied around the world is Diuron. There are various techniques for removing Diuron, the most important of which are adsorption and advanced oxidation. This review presents the characteristics, mechanisms, and emerging methods of removing Diuron. The use of absorbents, such as sludge-derived modified biochar (SDMBC600) and bottom ash waste (BAW-200), is discussed in detail. Additionally, the main features, benefits, and limitations of new technologies like hydrodynamic cavitation are enumerated. The effectiveness of novel adsorbents in Diuron removal is also discussed