Search results for " Oxidation"

Formation of 3-methyl-1,2,3-butanetricarboxylic acid via gas phase oxidation of pinonic acid – a mass spectrometric study of SOA aging

2012

Abstract. This paper presents the results of mass spectrometric investigations of the OH-initiated oxidative aging of α-pinene SOA under simulated tropospheric conditions at the large aerosol chamber facility AIDA, Karlsruhe Institute of Technology. In particular, the OH-initiated oxidation of pure pinic and pinonic acid, two well-known oxidation products of α-pinene, was investigated. Two complementary analytical techniques were used, on-line atmospheric pressure chemical ionization/mass spectrometry (APCI/MS) and filter sampling followed by liquid chromatography/mass spectrometry (LC/ESI-MS). The results show that 3-methyl-1,2,3-butanetricarboxylic acid (MBTCA), a very low volatile α-pine…

Considering syntrophic acetate oxidation and ionic strength improves the performance of models for food waste anaerobic digestion.

2021

Current mechanistic anaerobic digestion (AD) models cannot accurately represent the underlying processes occurring during food waste (FW) AD. This work presents an update of the Anaerobic Digestion Model no. 1 (ADM1) to provide accurate estimations of free ammonia concentrations and related inhibition thresholds, and model syntrophic acetate oxidation as acetate-consuming pathway. A modified Davies equation predicted NH3 concentrations and pH more accurately, and better estimated associated inhibitory limits. Sensitivity analysis results showed the importance of accurate disintegration kinetics and volumetric mass transfer coefficients, as well as volatile fatty acids (VFAs) and hydrogen up…

AMPK regulates macrophage polarization in adipose tissue inflammation and NASH

2013

Molecular and Translational Medicine, Dept. of Medicine I, University Medical Center, Johannes Gutenberg University Mainz, Langenbeckstrase 1,55116 Mainz, GermanyCOMMENTARY ON:Hematopoietic AMPK beta1 reduces mouse adipose tissue mac-rophage inflammation and insulin resistance in obesity. Galic S,Fullerton MD, Schertzer JD, Sikkema S, Marcinko K, Walkley CR,Izon D, Honeyman J, Chen ZP, van Denderen BJ, Kemp BE, Stein-berg GR. J Clin Invest 2011;121(12):4903–15. Copyright 2011.Reprinted with permission of American Society for ClinicalInvestigation.http://www.ncbi.nlm.nih.gov/pubmed/22080866Abstract: Individuals who are obese are frequently insulin resistant,putting them at increased risk of d…

Fibrillation of Human Serum Albumin at physiological pH is inhibited by oxidation

2014

Corrosion and wear resistance of coatings produced on AZ31 Mg alloy by plasma electrolytic oxidation in silicate-based K2TiF6 containing solution: Ef…

2022

Abstract In this research, plasma electrolytic oxidation coatings were prepared on AZ31 Mg alloy in a silicate-based solution containing K2TiF6 using bipolar and soft sparking waveforms with 10, 20, and 30% cathodic duty cycles. The coatings displayed a net-like surface morphology consisted of irregular micro-pores, micro-cracks, fused oxide particles, and a sintered structure. Due to the incorporation of TiO2 colloidal particles and the cathodic pulse repair effect, most of the micro-pores were sealed. Long-term corrosion performance of the coatings was investigated using electrochemical impedance spectroscopy during immersion in 3.5 wt.% NaCl solution up to 14 days. The coating grown by t…

Effect of simulated gastrointestinal digestion on plant sterols and their oxides in enriched beverages

2013

Abstract This study evaluates the bioaccessibility (percentage of soluble compound available for absorption) of plant sterols (PS) and their oxides (phytosterol oxidation products, POPs) after simulated gastrointestinal digestion in fruit (Fb), milk (M) and fruit-based milk beverages with (FbM a ) or without (FbM b ) tangerine juice. In beverages and their bioaccessible fraction (BF), campesterol, campestanol, stigmasterol, β-sitosterol and sitostanol were detected. Bioaccessibility of total PS ranged between 2.62 and 6.48%, FbM b yielding the highest value, followed by FbM a  > Fb > M. Campesterol/campestanol were the most bioaccessible PS. Only oxides of β-sitosterol were detected in beve…

Combination of different advanced oxidation processes and activated carbons for treatment of salt water

2015

Bilgewater is a corrosive polluted effluent from the bilge of ships that mainly originates from seawater infiltration and leakage of engine oil and fuel. Each year, thousands tons of hydrocarbons from bilge are discharged at sea. In order to prevent hydrocarbon discharge at sea from the bilge of ships, the Internation Maritime Organization (IMO) enacted the MARPOL 73/78 convention in which effluents are now limited to those with maximun oil content of 15 ppmv.

Carbons from second generation biomass as sustainable supports for catalytic systems

2018

In this study activated carbons were produced from the wood of three different wood species (pine, birch, spruce). The resulting activated carbons were characterized in bulk for ash content, carbon content (elemental analyses), specific surface area, and pore size distribution, and at the surface by measuring the autogenerated pH and studying their structure by XPS. All the samples presented high surface areas and appeared to be mesoporous materials (mesopores >80%). The carbons were then used as support for AuPt nanoparticles and tested in the liquid phase oxidation of glycerol (GLY) and in the hydrogenation of levulinic acid (LA), two important chemicals from cellulose-based biomass. The …

Chicken adaptive response to low energy diet: main role of the hypothalamic lipid metabolism revealed by a phenotypic and multi-tissue transcriptomic…

2019

AbstractBackgroundProduction conditions of layer chicken can vary in terms of temperature or diet energy content compared to the controlled environment where pure-bred selection is undertaken. The aim of this study was to better understand the long-term effects of a 15%-energy depleted diet on egg-production, energy homeostasis and metabolism via a multi-tissue transcriptomic analysis. Study was designed to compare effects of the nutritional intervention in two layer chicken lines divergently selected for residual feed intake.ResultsChicken adapted to the diet in terms of production by significantly increasing their feed intake and decreasing their body weight and body fat composition, whil…

Fine chemistry by TiO2 heterogeneous photocatalysis

2021

Abstract Heterogeneous TiO2 photocatalysis is a promising technology based on the capability of the semiconducting material to generate charges upon irradiation of suitable energy. The photogenerated electrons and holes, in turn, induce redox reactions involving species adsorbed on the surface of the photocatalyst, giving rise to chemical transformations. The presence of highly oxidizing radicals, thus generated, has long led to consider TiO2 photocatalysis only a nonselective oxidation process. In fact, so far it is possible to find in the literature many examples of its use in the field of environmental remediation aimed at the degradation of harmful molecules, although the studies are al…