Search results for "quantitative analysis"

Determination of triamterene in urine by HPLC using fluorescence detection and column-switching

1994

A liquid chromatographic method incorporating column-switching and fluorimetric detection for the determination of triamterene in untreated urine, is described. The urine samples (5 μL) were directly introduced onto an Hypersil ODS-C18, 30 μm (20 mm×2.1 mm I.D.) pre-column. Polar urinary compounds were removed by flushing the pre-column with water for 1 min, and the analyte was then switched onto an HP-LiChrospher RP C18,5 μm (125 mm×4mm ID) analytical column using an acetonitrile/phosphate buffer gradient elution. Fluorescence detection was performed at 230 nm excitation and 430 nm emission wavelengths. The recovery of drug was 102±2% in the 0.10–20.0 μg/mL concentration range, the limit o…

Enantioseparation of nuarimol by affinity electrokinetic chromatography-partial filling technique using human serum albumin as chiral selector

2008

The present paper deals with the enantiomeric separation of nuarimol enantiomers by affinity EKC-partial filling technique using HSA as chiral selector. Firstly, a study of nuarimol interactions with HSA by CE-frontal analysis was performed. The binding parameters obtained for the first site of interaction were n(1) = 0.84; K(1) = 9.7 +/- 0.3x10(3 )M(-1) and the protein binding percentage of nuarimol at physiological concentration of HSA was 75.2 +/- 0.2%. Due to the moderate affinity of nuarimol towards HSA the possibility of using this protein as chiral selector for the separation of nuarimol using the partial filling technique was evaluated. A multivariate optimization approach of the mo…

Transnationalism and Settlement of Latvian Emigrants in the Nordic Countries

2021

The intra-European migration flows have fostered debates about the intentions of migrants to settle in their destination country or return to their countries of origin. Based on a quantitative analysis of survey data ('N' = 1391), this article presents a typology of migration patterns among migrants from Latvia in the Nordic countries. Using two dimensions—attachment to the destination country and attachment to the country of origin—the article identifies and characterises the following four migration patterns: (1) bi-nationals, (2) settlers, (3) footloose migrants and (4) isolated migrants who focus on their country of origin and are willing to return (separated).

Elaboración un instrumento para conocer las características de la banda sonora de la programación infantil de televisión

2014

Television is one of the most important elements in the construction of the musical and audible reality of children and teenagers. It offers a selected and edited version of a musical environment, with an indisputable level of communicative and patrimonial influence. This paper is part of a research project that sets out to know what children are listening to in children’s television programming, in a sample of Latin American television coverage. The general objective has been to establish the parameters of everyday listening experiences and to create an instrument which is able to determine the objective elements of listening environments through their most notable medium: the soundtrack o…

Salikteņi rakstos par tirgvedību

2018

Rakstība angļu valodā vienmēr ir bijusi diezgan sarežģīta. Salikteņi ir vārdi, kam nav noteiktas rakstības sistēmas, tādēļ cilvēki tos raksta dažādi. Tādējādi šī darba mērķis ir analizēt salikteņus rakstos par tirgvedību. Kvalitatīvā un kvantitatīvā analīze tika izmantota kā pētniecības metode, un analīze tika veikta par salikteņiem, kas atrodami rakstos par tirgvedību vienā britu un vienā amerikāņu tirgvedības žurnālā. Šis pētījums ir parādījis, ka pārstāvētākais salikteņu veids ir īstie salikteņi (proper compounds) un izplatītākā salikteņu rakstība ir tos rakstīt kā vienu vārdu jeb “koprakstījumā” (solid compounds). Pētījuma rezultāti apstiprina, ka rakstos par tirgvedību izmantoto salikt…

Quantitative analysis of vitamin K1 and vitamin K1 2,3-epoxide in plasma by electron-capture gas-liquid chromatography.

1979

Improved method for quantitative analysis of vitamin K1i and vitamin K1 2,3-epoxide in human plasma by electron-capture gas-liquid capillary chromato…

1984

Determination of ascorbic acid in plasma and urine by high performance liquid chromatography with ultraviolet detection.

1999

Abstract A reliable simple reversed-phase liquid chromatographic method for the routine determination of ascorbic acid in plasma and urine with ultraviolet detection is described. This method enables the complete separation of the ascorbic acid peak from others with a recovery of above 95 % within 8 minutes. The method can be used for analysing multiple samples within a day. In addition, the storage conditions and stability of ascorbic acid in plasma and urine were investigated. Samples of plasma and urine can be stored on ice in darkness for at least 60 min without reduction of ascorbic acid concentration. Prepared samples can be stored in darkness at 4 °C for at least 120 min and in liqui…

2019

This paper describes data collected on 2 sets of 8 French red wines from two grape varieties: Pinot Noir (PN) and Cabernet Franc (CF). It provides, for the 16 wines, (i) sensory descriptive data obtained with a trained panel, (ii) volatile organic compounds (VOC) quantification data obtained by Headspace Solid Phase Micro-Extraction - Gas Chromatography - Mass Spectrometry (HS-SPME-GC-MS) and (iii) odor-active compounds identification by Headspace Solid Phase Micro-Extraction - Gas Chromatography - Mass Spectrometry - Olfactometry (HS-SPME-GC-MS-O). The raw data are hosted on an open-access research data repository [1].

An on-line system for preconcentration and determination of lead in wine samples by FAAS

2002

A flow injection method has been developed for the direct determination of free available Pb(II) and total Pb content in wine samples. The method is based on the chemical sorption of Pb(II), from pH 7 buffered solutions, on a packed polyurethane foam column, modified by addition of 2-(2-benzothiazolylazo)-p-cresol (BTAC). After this step, lead was directly eluted with a stream of 0.1 mol l(-1) HCl into an air C(2)H(2) flame in which lead was determined by atomic absorption spectrometry. Total lead was analyzed after sample digestion with nitric acid and hydrogen peroxide, being free available lead determined by direct sample on-line preconcentration and elution. The method provides a limit …