Hydrogen abstraction from organic acids by hydroxyl radicals is the initial rate- and selectivity-determining step in the photochemical oxidation of organic acids in the troposphere. To quantify the rate and selectivity of these reactions, the abstraction of hydrogen atoms at the acid, alpha, beta, gamma, and methyl positions was studied for valeric acid, C(4)H(9)COOH, using first principles ca...

In recent years, plasma treatments have given good results since they offer high technological efficiency with low waste generation. One of the most important characteristics of plasma methods is their action only on a thin surface layer, whereas the bulk of sample remains unchanged and the modified material keeps its chemical and mechanical properties. In this research, polyurethane membrane s...

In the current study, piezosensors based on molecularly imprinted polyimides with imprints of potassium sorbate and sodium benzoate were obtained. Molecularly Imprinted Polymers (MIPs) synthesized using a polyimide non-covalent imprinting technique. It was established that use 0.1 g/mL template concentration at thermochemical stage led to formation maximum number molecular film surface. Using s...

The present work describes the construction of a new modified electrode by casting the appropriate mixture of a metallocene, which has been introduced in the experimental part, as a mediator at the surface of glassy carbon (GC) electrode. The proposed modified GC electrode was used for the determination of ascorbic acid (AA) in phosphate buffer (PB) solution (pH = 4.0). When compared to bare GC...

Covalent organic framework (COF) membranes used for selective removal of CO2 were believed as an efficient and low-cost solution to energy and environmental sustainability. In this study, the amide modified COF nanosheet cluster with a 2D structure was facilely prepared through solid reaction, exhibiting good adsorption-based CO2 selectivity (223 at 273 K and 90 at 298 K) toward N2. Remarkably,...

a liquid membrane containing diethylene glycol monobutyl ether (2) shows specificity for k ion in transport while diethylene glycol dibutyl ether (1) was selective for na over k . as an extractant, ligand 2 exhibited pronounced extraction selectivity for k over na in comparison with ligand 1

Most work on ion selectivity in membrane channels has regarded K + channels and the structural and local field aspects that determine K + selectivity. Much less is known about little selective channels, such as the acetylcholine (ACh) receptor (AChR) channel. In general, multiple factors appear to underlie K + versus Na + selectivity; in addition to structural aspects, external forces derived f...