N-Hydroxyphthalimide-Catalyzed Oxidative Production of Phthalic Acids from Xylenes Using O2/HNO3 in an Ionic Liquid

A simple and mild process for oxidation of xylenes to phthalic acids using N-hydroxyphthalimide/O₂/HNO₃ in an ionic liquid, wherein the ionic liquid can be successfully recovered and reused, is described.     

Turbulent heat transfer and nanofluid flow in an annular cylinder with sudden reduction

Journal of Thermal Analysis and Calorimetry - In this study, catalyst formation [Pb(H2O)6][ATZ]·H2O (ATZ?=?azo tetrazolium anion) was successfully synthesized originally;...     

Synthesis and application of a novel functionalized magnetic MIL-101(Cr) nanocomposite for determination of aflatoxins in pistachio samples

Research on Chemical Intermediates - Herein, a novel method entitled magnetic solid-phase extraction based on MIL-101(Cr)/Fe3O4@SiO2@propylthiouracil composite was developed using the magnetite...     

A method for self-attenuation and sample-height correction for counting efficiency of HPGe using Marinelli beaker geometry

A procedure for self-attenuation and sample height correction in HPGe gamma spectrometry efficiency has been presented. An MCNP model of an HPGe detector was used to calculate the full energy peak efficiency (FEPE) for a group of different samples with different heights in Marinelli beaker geometry. A proper function has been fitted to the simulation results to obtain the correction function. The function has been used to calculate the FEPE of a spiked soil sample in different sample heights by considering the experimentally known FEPE of another standard solution source. A good agreement between the experiments and calculations have been shown.     

A study on optical,photoluminescence and thermoluminescence properties of ZnO and Mn doped-ZnO nanocrystalline particles

Pure ZnO and Mn (1%wt.) doped-ZnO nanocrystalline particles were synthesized by reverse micelle method. The structural properties of the nanoparticles were investigated by X-Ray Diffraction (XRD) and Transmission Electron Microscopy (TEM) techniques. UV–vis and photoluminescence (PL) spectroscopy was used for analyzing the optical properties of the nanoparticles. XRD and TEM results revealed the formation of ZnO and Mn doped-ZnO nanocrystalline particles with pure wurtzite crystal structure and average particle size of 18–21 nm. From UV–vis studies, the optical band gap energy of 3.53 and 3.58 eV obtained for ZnO and Mn doped-ZnO nanoparticles, respectively. Further optical analysis showed that the refractive index decreases from 2.35 to 1.35 with the change of wavelength. Room-temperature photoluminescence analysis of all samples showed four main emission bands including a strong UV emission band, a weak blue band, a week blue–green band, and a weak green band which indicated their high structural and optical quality. Moreover, the samples exposed to gamma rays sources of ¹³⁷Cs and ⁶⁰Co and their thermoluminescence properties were investigated. The thermoluminescence response of ZnO and Mn doped-ZnO nanocrystalline particles as a function of dose exhibited good linear ranges, which make them very promising detectors and dosimeters suitable for ionizing radiation.