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wszystkich: 28
Wyniki wyszukiwania dla: ELUTION
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Studies of the separation performance of silanized silica gel for simulated distillation
PublikacjaWe present the results of investigations of the chromatographic (sorptive) properties of silanized silica gel as a stationary phase for gas chromatography used for simulated distillation. Commercially available silanized sorbent (particle diameter range 63–200 m, average pore size 60 Å) was sieved to obtain the 80–100 mesh fraction (180–150 m). The obtained results revealed that silanized silica gel allows the complete separation...
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Sensitive determination of isoprostanes in exhaled breath condensate samples with use of liquid chromatography-tandem mass spectrometry
PublikacjaOxidative stress is the hallmark of various inflammatory lung diseases. Increased concentrations of reactive oxygen species in the lungs are reflected by elevated concentrations of oxidative stress markers in the breath, airways, lung tissue and blood. The aim of this work was to develop a method for the fast measurement of F2 isoprostanes in exhaled breath condensate (EBC) samples using equipment which is nowadays available and...
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Determination of flavanols by liquid chromatography with fluorescence detection. Application to the characterization of cranberry-based pharmaceuticals through profiling and fingerprinting approaches
PublikacjaIn this work, a new method based on reversed-phase high-performance liquid chromatography (HPLC) with fluorescence detection (FLD) was established for the determination of catechins and related oligomeric proanthocyanidins (PACs) in cranberry-based pharmaceuticals. Compounds were recovered by liquid extraction using methanol/water/hydrochloric acid (60:39:1, v:v:v) as the extraction solvent. The chromatographic separation was carried...
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Stopniowa chromatografia cienkowarstwowa w normalnych układach faz (NP-TLC), jako technika rozdzielania i oceny składu grupowego frakcji asfaltenowych z utleniania pozostałości próżniowej ropy naftowej
PublikacjaW pracy opisano wyniki badań nad opracowaniem metodyki oceny składu grupowego i czystości frakcji asfaltenowych techniką chromatografii cienkowarstwowej w normalnych układach faz (NP-TLC). Skupiono się na doborze takich parametrów/warunków rozdzielania, jak stężenie i masa próbki, a także skład i kolejność eluentów stosowanych podczas rozwijania chromatogramów TLC. Zastosowana trój-stopniowa metodyka polega na nałożeniu 5 µL frakcji...
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Determination of high-intensity sweeteners in beverages by high-performance liquid chromatography with mass spectrometry detection.
PublikacjaThe objective of the present study was to measure the concentration of nine high intensity sweeteners (acesulfame-K, aspartame, alitame, cyclamate, dulcin, neohesperidin dihydrochalcon, neotame, saccharin and sucralose) in different types of beverages available on the polish market. The proposed methodology reported here consists of a extraction with buffer composed of formic acid and N,N-diisopropylethylamine (pH 4.5) followed...
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Release of selected chemical elements from shale drill cuttings to aqueous solutions of different pH
PublikacjaThe effect of pH changes on leachability of light and heavy metals from shale drill cuttings generated from unconventional shale gas production was investigated. Cuttings, being the primary byproduct generated from drilling operations, belong to the potentially hazardous type of wastes due to presence of heavy and radioactive elements and remains of drilling fluid. In this regard, assessment of potentially dangerous components...
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The lethal effect of hydrotechnical concrete on freshwater Bivalvia
PublikacjaMost hydrotechnical buildings under construction demand the concrete mixture to be set directly under water. The main reason for such a procedure is to limit the washing away of the the concrete binding mixture and to increase the efficiency of organisation of work so as to ensure continuity in concreting. The impact on the aquatic environment of recent developments in concrete technology and the use of new components has not yet...
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Determination of nine high-intensity sweeteners in various foods by high-performance liquid chromatography with mass spectrometric detection
PublikacjaAn analytical procedure involving solid-phase extraction (SPE) and high-performance liquid chromatography-mass spectrometry has been developed for the determination of nine high-intensity sweeteners authorised in the EU; acesulfame-K (ACS-K), aspartame (ASP), alitame (ALI), cyclamate (CYC), dulcin (DUL), neohesperidin dihydrochalcone (NHDC), neotame (NEO), saccharin (SAC) and sucralose (SCL) in a variety of food samples (i.e. beverages,...