Search results for "LUE"
showing 10 items of 8383 documents
Effect of cooking on oxalate content of pulses using an enzymatic procedure.
2003
An enzymatic method proposed for the determination of oxalate in urine is adapted for the estimation of soluble oxalate content in beans, chickpeas and lentils. Oxalates were extracted in water by refluxing for 2 h. The method is based on the oxidation of oxalate by the oxidase and the determination of the resulting hydrogen peroxide, which in presence of peroxidase, 3-methyl-2 benzotiazinolone and 3-dimethylamino benzoic, gives an indamine compound with an absorption maximum at 590 nm. The linearity (from 0.015 to 0.6 mM) of the method is adequate to the analysis of oxalate contents in pulses, and the inter-day precision of the method expressed as relative standard deviation was good (3.01…
Vacuum-ultraviolet absorption of interstitial O2 and H2O molecules in SiO2 glass
2006
Abstract Vacuum-ultraviolet (VUV) absorption of O 2 and H 2 O molecules incorporated in interstitial voids in SiO 2 glass by thermal annealings was examined. Interactions of the interstitial molecules with the surrounding SiO 2 glass network lead to a redshift of the VUV absorption band of interstitial O 2 , while a blueshift of that of interstitial H 2 O, both accompanied by an increase in the intensity of the absorption bands. The Coulomb repulsion, London dispersion, and hydrogen bonding are the main interactions responsible for the modification of the VUV absorption bands.
University Transitions and Gender: From Choice of Studies to Academic Career Development
2014
Based on the results of the authors' research using a case study of a Spanish university, the sociological component of gender is an important factor in building transitions at university. When the authors refer to university transitions they are talking about two periods. Firstly, they refer to the transition of undergraduate students from upper secondary education. The authors detect differences in the choices of studies, in the identification of professional models and in the university admission process. Secondly, they refer to the transition from research grant-holders to teaching and research staff. They explore the construction of social expectations and representations that researc…
La herencia clásica palladiana en dos proyectos catedralicios valencianos: la renovación de la Puerta de los Apóstoles
2005
El presente artículo pretende analizar los proyectos de renovación de la Puerta de los Apóstoles, en la catedral de Valencia. Estos proyectos son los de Vicente Marzo y José García, realizados ambos en el año 1796. A partir de ellos se buscarán sus influencias que remiten, especialmente, a I Quattro Libri dell'Architettura de Palladio. (A)
Mindfulness, acceptance and value-based intervention for burnout : mediational roles of learning the elements of the intervention on outcomes
2015
The effects of mindfulness-based interventions and ACT on mindfulness and well-being have received a lot of interest, and their mechanisms of change have been studied recently, but still some mechanisms are missing the research attention. The mechanisms of the change that happens during an intervention with people who suffer from work related burnout, have been examined by only a couple of studies. The present study aimed to investigate these mechanisms by looking at the mediating effects of learning mindfulness, acceptance and value-based working (MAV) skills which were measured with a novel Learning Questionnaire developed for the present research project. The data of the present study wa…
INTEGRAL observations of the peculiar BeX System SAX J2103.5+4545
2004
We present an INTEGRAL data analysis of the X-ray transient \object{SAX J2103.5+4545} during two outbursts detected in December 2002. The INTEGRAL coordinates and error circle agree with the position of the recently proposed optical counterpart. A power-law plus cut-off model provided a good fit to the 4-150 keV spectrum yielding a photon index of 1.0+-0.1, a cut-off energy E_cut=7.6+-2.0 keV and a folding energy E_fold=30.9+-2.5 keV. The X-ray luminosity in the 4-150 keV energy range was found to be 6.0x10^36 erg/s, assuming a distance of 6.5 kpc. This luminosity, together with the derived photon index, indicate that the source is in a bright state. A 354.9$+-0.5 second pulse period is mea…
Development of a GC–MS/MS strategy to determine 15 mycotoxins and metabolites in human urine
2014
The widespread mycotoxins contamination of food commodities has made the monitoring of their levels essential. To overcome the disadvantages of the indirect approach by food analysis, detection of mycotoxin as biomarkers in urine provides a useful and specific data for exposure assessment to these food contaminants. In this work, a sensitive, rapid and accurate method based on gas chromatography-tandem mass spectrometry procedure to determine 15 mycotoxins and metabolites in human urine was optimized and validated taking into consideration the guidelines specified in Commission Decision 2002/657/EC and 401/2006/EC. A salting-out assisted acetonitrile-based extraction was used for sample pre…
Determination of free formaldehyde in cosmetics containing formaldehyde-releasing preservatives by reversed-phase dispersive liquid-liquid microextra…
2017
Abstract An analytical method for the determination of traces of formaldehyde in cosmetic products containing formaldehyde-releasing preservatives has been developed. The method is based on reversed-phase dispersive liquid–liquid microextraction (RP-DLLME), that allows the extraction of highly polar compounds, followed by liquid chromatography–ultraviolet/visible (LC–UV/vis) determination with post-column derivatization. The variables involved in the RP-DLLME process were studied to provide the best enrichment factors. Under the selected conditions, a mixture of 500 μL of acetonitrile (disperser solvent) and 50 μL of water (extraction solvent) was rapidly injected into 5 mL of toluene sampl…
Renewable polyol obtained by microwave-assisted alcoholysis of epoxidized soybean oil: Preparation, thermal properties and relaxation process
2019
[EN] The soybean oil polyol (SOP) use as feedstock in the polyurethane industry has been recently emphasized due to its excellent resistance to hydrolysis, which is also applicable in coatings and thermal insulation. In this article, the SOP was obtained by a very fast microwave-assisted alcoholysis of epoxidized soybean oil (ESO). The preparation method, thermal properties, and relaxation process were evaluated. High yields as opening and consumption epoxy group and selectivity of 99.8 mol%, 985 mol%, and 71.2 mol% were obtained. Through titrations, nuclear magnetic resonance and gel permeation chromatography were identified parameters as 0.32 mg KOH.g(-1) acid number, 190 mg KOH.g(-1) hyd…
Nano-magnetic potassium impregnated ceria as catalyst for the biodiesel production
2019
Abstract The main objective of this work comprises the investigation of biodiesel production from rapeseed oil using potassium impregnated Fe3O4-CeO2 nanocatalyst. The various concentration of potassium impregnated Fe3O4-CeO2 was screened for catalytic conversion of rapeseed oil to triglyceride methyl ester. The 25 wt % potassium impregnated Fe3O4-CeO2 nanocatalyst showed best biodiesel production. Nanocatalyst was characterized by FTIR, XRD, SEM, TEM, BET and Hammett indicator for basicity test. The characterization of biodiesel was performed with GC-MS, 1H and 13C NMR. Moreover, the optimum reaction parameters such as catalyst amount (wt %), oil to methanol ratio, reaction time and reacti…