Search results for " Oxidation"
showing 10 items of 675 documents
Highly Active Co3O4-Based Catalysts for Total Oxidation of Light C1–C3 Alkanes Prepared by a Simple Soft Chemistry Method: Effect of the Heat-T…
2021
9 figures, 2 tables.
Promoting the activity and selectivity of high surface area Ni–Ce–O mixed oxides by gold deposition for VOC catalytic combustion
2011
Gold supported on nickel cerium oxide catalysts (Ni–Ce–O) have been studied for the total oxidation of propane, as a model for hydrocarbon volatile organic compound emission control. High surface area Ni–Ce–O catalysts were synthesized using a very simple evaporation method, where cerium and nickel salts were evaporated in the presence of a mixture of methanol and oxalic acid. Gold catalysts were prepared following a deposition–precipitation method. A very efficient catalyst for the oxidation of propane, in terms of both activity and selectivity, was obtained. This high activity has been related to the high surface area of the catalyst (and therefore to the presence of more active sites ava…
Heterogeneous fenton oxidation using magnesium ferrite nanoparticles for ibuprofen removal from wastewater: optimization and kinetics studies
2020
In this study, the catalytic properties of Fenton-like catalyst based on magnesium ferrite nanoparticles for IBP degradation were examined. Structural and morphological studies showed the low crystallinity and mesoporous structure for the catalyst obtained via a glycine-nitrate method. The influences of catalyst dosage, oxidant concentration, and solution pH on the pollutant degradation were investigated. The pseudo-first-order model describes kinetic data, and under optimal condition (catalyst dose of 0.5 g L-1, H2O2 concentration of 20.0 mM, and pH of 8.0), apparent rate constant reached 0.091 min-1. It was shown that Fenton reaction was mainly induced by iron atoms on the catalyst surfac…
Total oxidation of naphthalene using bulk manganese oxide catalysts
2013
Several Mn2O3 catalysts have been synthesized using different preparation methods and tested for the total oxidation of naphthalene, a model polycyclic aromatic compound. The catalysts have been characterized by several physico-chemical techniques such as XRD, TPR, XPS, EDX and TEM. The surface area of the catalyst seems to be of paramount importance, since the mass normalized activity of catalysts increases as the surface area of the Mn2O3 catalysts increases. Consequently, a high surface area ordered mesoporous Mn2O3 catalyst, obtained through a nanocasting route using mesoporous KIT-6 silica as a hard template, was the most efficient catalyst for the deep oxidation of naphthalene. In add…
Effects of insulin deficiency on exercise-induced acute responses in the regulation of fatty acid oxidation in mouse gastrocnemius muscles
2014
Insulin is a hormone that plays an important role in the regulation of the metabolism of all the main nutrients. Its main function is to stimulate glucose uptake and disposal or utilization by the cells and thus to decrease blood glucose concentration. However, it also inhibits breakdown of proteins and lipids and promotes their synthesis. Type 1 diabetes is a disease in which insulin secretion is impaired because of destruction of pancreatic β-cells. It is characterized by hyperglycemia and increased reliance on fat oxidation. This is seen also as altered gene expression patterns. The purpose of this study was to look into the effects of insulin deficiency on exercise-induced acute respons…
Eco-friendly cavity-containing iron oxides prepared by mild routes as very efficient catalysts for the total oxidation of VOCs
2018
Iron oxides (FeOx) are non-toxic, non-expensive and environmentally friendly compounds, which makes them good candidates for many industrial applications, among them catalysis. In the present article five catalysts based on FeOx were synthesized by mild routes: hydrothermal in subcritical and supercritical conditions (Fe-HT, Few200, Few450) and solvothermal (Fe-ST1 and Fe-ST2). The catalytic activity of these catalysts was studied for the total oxidation of toluene using very demanding conditions with high space velocities and including water and CO2 in the feed. The samples were characterized by X-ray diffraction (XRD), scanning and high-resolution transmission electron microscopy (SEM and…
Oxidation of silicon nanoparticles produced by ns laser ablation in liquids
2014
The investigation of nanoparticles produced by ns pulsed Nd:YAG laser ablation of silicon in liquids is reported. Combined characterization by morphological and structural techniques shows that these nanoparticles have a mean diameter of ~3 nm and a core-shell structure consisting of a Si-nanocrystal surrounded by a layer of oxidized Si. Time resolved luminescence spectra evidence visible and UV emissions: a broad band around 1.9 eV originates from Si-nanocrystals, while two bands centered at 2.7 eV and 4.4 eV are associated with oxygen deficient centers in the SiO2 shell.
Electrochemical Oxidation of Hf-Nb Alloys as a Valuable Route to Prepare Mixed Oxides of Tailored Dielectric Properties
2018
Metal oxides with high dielectric constant are extensively studied in the frame of substituting SiO2 as gate dielectric in nanoelectronic devices. Here, high-k mixed HfO2/Nb2O5 oxides are prepared by a facile electrochemical route starting from sputtering-deposited Hf–Nb alloys with several compositions. Transmission electron microscopy, grazing incidence X-ray diffraction, and glow discharge optical emission spectroscopy are employed to study the oxide structures, disclosing a crystalline–amorphous transition of the electrochemically prepared oxides by increasing the Nb content. Photo-electrochemical measurements allow the observation of optical transitions ascribed to localized states ins…
Drumstick (
2019
The present work investigated the efficacy of Moringa flower (MF) extract to develop a functional chicken product. Three groups of cooked chicken nuggets—control (C), T1 (with 1% MF) and T2 (2% MF)—were elaborated and their physicochemical, nutritional, storage stability and sensory attributes were assessed during refrigerated storage at 4 °C up to 20 days. In addition, MF extracts were characterised in terms of chemical composition, total phenolic content and its components using high-performance liquid chromatography with a diode-array detector (HPLC-DAD), dietary fibre and antioxidant capacity. MF contained high protein (17.87 ± 0.28 dry matter), dietary fibre (36.14 ± 0.77 dry matter) a…
PPAR in Cardiovascular Disorders
2016
Peroxisome proliferation-activated receptors (PPARs) are ligand-inducible transcription factors that, upon binding their ligands, translocate into the nucleus, where they regulate transcription of numerous genes that have the peroxisome proliferator response element (PPRE) in the promoter region [1]. In humans, there are 3 PPAR isoforms: PPAR-α, PPAR-β/δ, and PPAR-γ. The isoforms have partially overlapping spectra of activity and are differently expressed in organs and tissues [2]. PPAR-α is expressed mostly in tissues characterized by high catabolic activity, including skeletal muscle, liver, proximal tubular cells in kidneys, and brown fat. This PPAR isoform regulates components of β-oxid…