Search results for "quantitative analysi"
showing 10 items of 307 documents
Food and Environment: Trace Element Content of Hen Eggs from Different Housing Types
2013
AbstractEleven trace elements (Ba, Cu, Fe, Mn, Ni, Pb, Rb, Se, Sr, V, Zn) were quantitatively determined in hen egg samples collected from different poultry housing types (large-scale poultry farms, organic farms and domestic farms) over the territory of Latvia. Samples were wet digested and quantitatively analysed by total reflection X-ray fluorescence spectrometry (TXRF). The accuracy of analytical method was verified with analysis of certified reference material NCS ZC73017 (GSB-10)-Apple. The most variable range of concentrations and the highest content of elements were determined for hen egg samples derived from organic farms, while egg samples from domestic farms and poultry farms mos…
Analysis of Diuretics in Urine by Column-Switching Chromatography and Fluorescence Detection
1997
The potential of column-switching chromatography and fluorescence detection for the analysis of diuretics in urine is evaluated. Sample cleanup and chromatographic parameters have been optimized to achieve maximum sensitivity for the detection and quantification of some relevant diuretics. On the basis of these studies, an on-line procedure for the simultaneous determination of amiloride, furosemide, bumetanide and triamterene is presented. The linearity, precision, accuracy and sensitivity of the method are discussed. The utility of the described approach has been tested by analysing urine samples obtained after administration of bumetanide.
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…