Fabrication and electrochemical property modification of mixed matrix heterogeneous cation exchange membranes filled with Fe<Subscript>3</Subscript>O<Subscript>4</Subscript>/PAA core-shell nanoparticles

In the current research, iron oxide nanoparticles were functionalized by acrylic acid polymerization. The Fe₃O₄/PAA core-shell nanoparticles were utilized for the modification of cation exchange membranes. Ion exchange membranes were prepared by solution casting technique using cation exchange resin powder as functional group agent and tetrahydrofuran as solvent. FTIR analysis proved the formation of PAA on nanoparticles. The SOM images also showed uniform particle distribution for the prepared membrane relatively. The membrane water content was declined from 30 to 17 % by increase of nanoparticle content ratio in membrane matrix. The contact angle measurements showed that membrane surface hydrophilicity was improved by utilizing of nanoparticles in the membrane matrix. The membrane potential, permselectivity, and transport number were improved initially by increase of nanoparticle concentration in the casting solution and then began to decrease by more additive concentration. Membrane ionic flux and permeability were enhanced initially by increase of nanoparticle loading ratio up to 0.5 %wt in membrane matrix and then showed decreasing trend by more increase of nanoparticle concentration from 0.5 to 4 %wt. Membrane areal electrical resistance was decreased sharply by utilization of nanoparticles up to 0.5 %wt in membrane matrix then began to increase by more additive concentration. The prepared membranes exhibited superior selectivity and low ionic flux at neutral condition compared to other acidic and alkaline environments.     

Manganese(II), cobalts(II) and nickel(II) complexes of tris(2-pyridyl)phosphine and their catalytic activity toward oxidation of tetralin

Abstract  

Monomeric Mn²⁺, Co²⁺ and Ni²⁺ complexes of tris(2-pyridyl)phosphine (P(2-py)₃ were synthesized through the reaction of the hydrated metal(II) chlorides with P(2-py)₃ in near-quantitative yields. The solid-state structure of the Mn complex was determined by single-crystal X-ray diffraction. All three complexes were tested as homogeneous catalysts for the oxidation of tetralin to α-tetralone with tert-butyl hydroperoxide (TBHP) as oxidant. The influences of temperature, solvent, catalyst molar ratio and time of the reaction on the catalyzed reactions were investigated.     

Adapting the ionic transfer behavior of cation exchange membrane incorporated with SiO2/PAA composite nanoparticles

Ionics - In this study, silicon dioxide nanoparticles (SiO2 NPs) were functionalized by polyacrylic acid (PAA) then used as the modifier agent in polyvinyl chloride (PVC)-based heterogeneous cation...     

Synthesis and structural studies of some fluorescent group XII metal complexes with a terpyridine based ligand

Three 4′-(2-thienyl) substituted terpyridine (thioterpy) complexes of cadmium(II) and mercury(II) have been synthesized and fully characterized by spectroscopies. According to the crystallographic studies, the packing of these complexes was stabilized by several intermolecular interactions such as hydrogen bonding, C-H?π and π?π. Finally, the florescent properties of the prepared complexes have been investigated.     

铯改性的沸石Y上醇类和胺类的氰乙基化反应(英文)

Zeolite Y modified by cesium and magnesium ions was prepared by ion-exchange and impregnation methods, and its activity in the cyanoethylation of aliphatic and aromatic alcohols and amines was investigated. During the preparation of some samples, the transformation of zeolite Y into a pollu-cite-type phase occurred. This phase exhibited good activity in the cyanoethylation of aliphatic alcohols. The prepared solids modified by the impregnation method were more active than the ion-exchanged solids. The activities of the catalysts, in contrast to other basic solids, were scarcely affected by the presence of air or moisture. A correlation between catalyst basicity and catalytic activity is discussed. The catalysts were characterized by X-ray diffraction, volumetric nitrogen adsorption surface area measurement, and CO2 temperature-programmed desorption. Scanning electron microscopy revealed that the particles of the modified nanocatalysts were 40 nm. The reaction of acrylonitrile with linear alcohols in the presence of the catalysts was accelerated by microwave irradiation.     

Cellulose-Supported Ni(NO3)2 · 6H2O/2,4,6-Trichloro-1,3,5-triazine (TCT) as a Mild,Selective, and Biodegradable System for Nitration of Phenols

Nitration of certain phenols and naphthols in the presence of biodegradable cellulose-supported Ni(NO₃)₂ · 6H₂O/2,4,6-trichloro-1,3,5-triazine was carried out in acetonitrile at room temperature. Ortho nitrated phenols were obtained regioselectively within a short reaction time with good yields. The reaction condition was mild, and the employed cellulose could be recovered several times for further use.      

Analysis of concrete labyrinth shielding and radiation dose for APF plasma focus neutron source by FLUKA Monte Carlo code

In this paper Monte Carlo simulations have been performed for the attenuation of neutrons radiation produced by a 4 kJ plasma focus device through labyrinth shielding design with various thicknesses. At the test site that will be fired with deuterium and deuterium fusion (D–D) resulting in a yield of about 10⁹ fusion neutrons of 2.45 MeV. This poses a radiological hazard to scientists and personnel operating the device. The goal of this study is to evaluate various shielding options under consideration for the plasma focus operating with D–D fusion. Shields of varying neutrons-shielding effectiveness were investigated using concrete materials. The most effective shield between labyrinth structure allowed almost 9.52E+6 shots per year while keeping personnel under 20 mSv of dose. The most expensive shield that is used labyrinth shield with 75 cm concrete thickness on the walls allowed almost 9E+8 shot per year.     

A Rapid Determination of Taurine in Human Plasma by LC

Taurine is an amino acid which is not incorporated into proteins but found in the cytosol of many mammalian cells, in high concentrations (2–30 mM). Increase in plasma taurine concentration has already been reported after surgical trauma, X-radiation, muscle necrosis, carbon tetrachloride-induced liver damage, and paracetamol overdose. Plasma taurine concentration was measured using LC with fluorescence detection following derivatization by o-phtalaldehyde plus 3-mercapto-propionic acid and α-aminobutyric acid as internal standard. Under these conditions the retention time of taurine was 10 min. This method was sensitive enough, to quantify 150 pg mL⁻¹ and detect 50 pg mL⁻¹ of taurine ranging normally between 65 and 179 mmol L⁻¹ (8–22 μg mL⁻¹). The validated method allowed simple determination of human plasma taurine in pharmacokinetic and biomarker studies.

     

Effect of synthesis parameters on the crystallinity of EU-1 zeolite for the m-xylene isomerization reaction

Russian Journal of Applied Chemistry - The EU-1 zeolite with Si/Al = 25 was synthesized by hexamethonium bromide as a template. The effects of crystallization time, synthesis temperature, and the...