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Determination of tributyltin in marine sediment: Comit� Consultatif pour la Quantit� de Mati�re (CCQM) pilot study P-18 international intercomparison
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Ultrasound assisted dispersive solid phase microextraction using polystyrene-polyoleic acid graft copolymer for determination of Sb(III) in various bottled beverages by HGAAS
PublikacjaA new polyoleic acid-polystyrene (PoleS) block/graft copolymer was synthesized and applied as adsorbent for ultrasound assisted dispersive solid phase microextraction (UA-DSPME) of Sb(III) in different bottled beverages and analysis using hydride generation atomic absorption spectrometry (HGAAS). Adsorption capacity of the PoleS was 150 mg g−1. Several sample preparation parameters such as sorbent amount, solvent type, pH, sample...
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Określenie szybkości korozji stopu AlSi13Mg1CuNi nadtopionego laserowo w warunkach kriogenicznych = Corrosion rate determination of AlSi13Mg1CuNi alloy laser remelted at cryogenic conditions
PublikacjaW pracy przedstawiono wyniki badania szybkości korozji stopu AlSi13Mg1CuNi nadtopionego laserowo w warunkach kriogenicznych. Stop eksponowano w 0,01 M roztworze kwasu siarkowego H2SO4
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Determination of denaturation temperature of connective tissue proteins by viscometric measurements.
Dane BadawczeViscometric denaturation temperature of connective tissue proteins was determined by measuring viscosity with a Brookfield viscometer, using a LV SC4 - 18, 25 or LV3 spindle and shear rates from 50 to 110 s-1 (Fig.1). Freeze-dried protein samples were dissolved in 0.5 M acetic acid at 4 °C and concentration of 20 mg/mL. The solution was stirred with...
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Determination of viscosity changes in dietary supplement solutions depending on temperature.
Dane BadawczeThe rheological characteristics of dietary supplement solutions were made based on viscosity measurement using a Brookfield viscometer, using the LV SC4 - 18 spindle and a shear rate of 53 s-1 (Fig.1).
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Determination of changes in viscosity of chitosan solutions depending on shear rate.
Dane BadawczeThe rheological characteristics of chitosan solutions were based on viscosity measurements using a Brookfield viscometer, using LV SC4 - 25 spindles and shear rates from 4 to 53 s-1 (Fig. 1). Chitosan solutions with different molecular weights (low, medium and high) were prepared in concentrations from 1.5 to 3.0% in 0.5M acetic acid. The data allowed...
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Determination of eight artificial sweeteners and common Stevia rebaudiana glycosides in non-alcoholic and alcoholic beverages by reversed-phase liquid chromatography coupled with tandem mass spectrometry.
PublikacjaThe method for the determination of acesulfame-K, saccharine, cyclamate, aspartame, sucralose, alitame, neohesperidin dihydrochalcone, neotame and five common steviol glycosides (rebaudioside A, rebaudioside C, steviol, steviolbioside and stevioside) in soft and alcoholic beverages was developed using high-performance liquid chromatography and tandem mass spectrometry with electrospray ionisation (HPLC-ESI-MS/MS). To the best of...
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Determination of parent and methylated polycyclic aromatic hydrocarbons in water samples by dispersive liquid–liquid microextraction–two dimensional gas chromatography–time-of-flight mass spectrometry
PublikacjaPolycyclic aromatic hydrocarbons (PAHs) are contaminants frequently found in environmental waters. Owing to their toxic effects, it is important to develop analytical methodologies that allow their fast and reliable determination. Dispersive liquid–liquid microextraction (DLLME) allows a quick extraction of analytes with little organic solvent consumption. The best results regarding sample preparation are obtained when 40 mL of...
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Current trends in analytical strategies for determination of polybrominated diphenyl ethers (PBDEs) in samples with different matrix compositions – Part 1.: Screening of new developments in sample preparation
PublikacjaPolybrominated diphenyl ethers (PBDEs) are ubiquitous compounds in the environment. Restrictions on the use of PBDEs introduced at the beginning of the 21st century have not eliminated these highly persistent and bioaccumulative compounds from the environment. Despite many existing regulations to control and phase out, extensive research on PBDEs is still necessary to fully evaluate the hazard their create to the environment. In...
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Chromium‑based metal organic framework for pipette tip micro‑solid phase extraction: an effective approach for determination of methyl and propyl parabens in wastewater and shampoo samples
PublikacjaAbstract Background A chromium-based metal organic framework was synthesized and employed as an efficient sorbent for pipette tip micro-solid phase extraction and preconcentration of parabens from wastewater and shampoo samples up to sub-ppb level before their spectrophotometric analysis. Results Factors affecting preconcentration including volume and type of solvent, amount of sorbent, number of extraction, and volume and pH of...
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Multi-residue method for the determination of 16 recently used pesticides from various chemical groups in aqueous samples by using DI - SPME coupled with GC-MS
PublikacjaA simple and solvent-free multi-residue method has been optimized to determine 16 currently used pesticides from different chemical groups in aqueous samples. The extraction of analytes was carried out with direct immersion solid-phase microextraction (DI-SPME) and for the identification and quantitative determination gas chromatography coupled with mass spectrometry (GC-MS) was applied. Two commonly used adsorbent coatings have...
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Novel liquid chromatography method based on linear weighted regression for the fast determination of isoprostane isomers in plasma samples using sensitive tandem mass spectrometry detection
PublikacjaA simple, fast, sensitive and accurate methodology based on a LLE followed by liquid chromatography–tandem mass spectrometry for simultaneous determination of four regioisomers (8-iso prostaglandin F2α, 8-iso-15(R)-prostaglandin F2α, 11β-prostaglandin F2α, 15(R)-prostaglandin F2α) in routine analysis of human plasma samples was developed. Isoprostanes are stable products of arachidonic acid peroxidation and are regarded as the...
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Sensitive method for determination of benzoic acid in beverages and food samples using air–assisted hydrophobic deep eutectic solvent-based dispersive liquid-liquid microextraction
PublikacjaA simple, reliable and rapid air–assisted hydrophobic deep eutectic solvent-based dispersive liquid–liquid microextraction (AA-HDES-DLLME) was developed for analysis of benzoic acid in various beverages and food samples. The final determination stage was performed via UV–visible spectrophotometry. The key parameters (extraction time, HDES type and volume, dispersant volume, pH and sample volume) of the AA-HDES-DLLME method were...
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Ultrasound assisted solvent extraction of porous membrane-packed samples followed by liquid chromatography-tandem mass spectrometry for determination of BADGE, BFDGE and their derivatives in packed vegetables
PublikacjaThe problem of the presence of trace organic pollutants in food is of growing importance due to increasing awareness about their impact on newborns, infants and adults of reproductive age. Despite the fact that packaged food products offer many advantages, packaging can be a source of contamination for stored food. Thus, monitoring such pollution in food is of high importance. In this work, a novel methodology based on the solvent...
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Comparison of hydrophilic interaction and reversed phase liquid chromatography coupled with tandem mass spectrometry for the determination of eight artificial sweeteners and common steviol glycosides in popular beverages
PublikacjaHydrophilic interaction liquid chromatography (HILIC) coupled with tandem mass spectrometry (MS/MS) was used to separate artificial and natural sweeteners approved for use in European Union (EU). Among three tested HILIC columns (BlueOrchid PAL-HILIC, Ascentis Express Si and Acclaim™ Trinity™ P2) the last one was selected for the development of HILIC method due to the best results obtained with it. Early eluting and coeluting compounds...
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Determination of profenofos in seawater and foodstuff samples after its molecularly imprinted polymer pipette-tip micro solid phase extraction optimized by response surface methodology
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Application of response surface methodology for optimization of metal–organic framework based pipette-tip solid phase extraction of organic dyes from seawater and their determination with HPLC
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Comparison of Air-Assisted, Vortex-Assisted and Ultrasound-Assisted Dispersive Liquid–Liquid Microextraction for the Determination of BTEX Compounds in Water Samples Prior to GC-FID Analysis
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Przegląd metod oznaczania pozostałości pestycydów i polichlorowanych bifenyli w próbkach żywności = Methods of determination of residues of pesticides and polychlorinated biphenyls in food samples - a review
PublikacjaOznaczanie pozostałości pestycydów i analitów z grupy polichlorowanych bifenyli w próbkach żywności wymaga zastosowania specyficznych technik w zakresie przygotowania próbki do analizy, jak i samych technik analizy instrumentalnej, pozwalających na uzyskanie bardzo niskiej granicy oznaczalności. Problemem związanym ze stosowaniem związków z grupy pestycydów i polichlorowanych bifenyli jest konieczność kontroli ich pozostałości...
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Use of porous glass and silica gel as support media of a surface compound for generation of analytes in gaseous standard mixtures. New method for the determination of the amount of analyte generated
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Wyznaczanie współczynników dyfuzji tlenku węgla (IV) przez membrany wysycone cieczą jonową = Determination of carbon dioxide diffusion coefficients in supported ionic liquids membranes
PublikacjaWykazano możliwość zastosowania imidazoliowych cieczy jonowych osadzonych na nośnikach polimerowych SILM (supported ionic liquids membranes) do absorpcji CO2. W badaniach wykorzystano sole imidazoliowe posiadające w strukturze aniony fluoroalkilowe typu [Tf2N] i [TfO], które selektywnie separują tlenek węgla (IV). Wyznaczono współczynniki dyfuzji CO2 przez poszczególne SILM na podstawie ilości dyfundującego CO2 przez powierzchnię...
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Problemy z oznaczaniem zawartości fazy stałej z zastosowaniem normy ISO 8292 = Problems with the solid fat content determination using the ISO 8292 standard.
PublikacjaZawartość fazy stałej (SFC) jest parametrem charakteryzującym właściwości fizyczne i użytkowe tłuszczów stałych. Otrzymanie prawidłowego wyniku zależy od zastosowania odpowiedniej procedury termostatowania próbki przed pomiarem, a ta z zależy od rodzaju badanego tłuszczu. Przed oznaczeniem SFC wszystkie TAG, które są stałe w temperaturze 0oC powinny wykrystalizować, a tłuszcz osiągnąć trwałą formę krystaliczną. Pierwsza norma IUPAC...
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Determination of mechanical properties of human stomach tissues subjected to uniaxial stretching
Dane BadawczeThe aim of the study was to determine the biomechanical properties of the walls of the human stomach. The samples were fragments of the human stomach obtained after sleeve gastrectomy. Samples cut parallel to the stomach curves and perpendicular to the stomach curves were tested in each series. All samples were subjected to uniaxial stretching. During...
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Determination of the ratio resistors in the input circuits of the NTC10k thermistor calibration system
Dane BadawczeThe presented data set is part of the research aimed at determining the actual characteristics of each thermistor in a package of twenty NTC10k type sensors.
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Determination of viscosity changes of protein hydrolyzate solutions depending on shear rate
Dane BadawczeRheological characteristics of connective tissue protein solutions were made on the basis of viscosity measurement using a Brookfield viscometer using LV SC4 - 27 spindles and shear rate of 85 s-1 (Fig. 1). Solutions of protein hydrolysates with a concentration of 2% in 0.5M acetic acid were prepared.
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Determination of changes in viscosity of chitosan cosmetic preparations depending on shear rate.
Dane BadawczeThe rheological characteristics of chitosan were made on the basis of a viscosity measurement using a Brookfield viscometer, using LV SC4 - 25 spindles and shear rates from 0.3 to 32 s-1 (Fig. 1). Chitosan solutions at 1% concentrations in acetic acid were prepared. The samples were subjected to storage tests.
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Green, simple analytical method for biogenic amines determination in fruit juice samples using salting-out assisted liquid-liquid microextraction and gas chromatography-mass spectrometry
PublikacjaSalting-out assisted liquid-liquid microextraction (SALLME) was integrated with the derivatization procedure to establish a one-step sample pre-treatment approach for rapid analysis of 14 biogenic amines (BAs) in fruit juices. The methodology consists of salting-out of analytes, derivatization with ethyl chloroformate (ECF), extraction with ethyl acetate (EtAc), and the analysis of the derivatized BAs using gas chromatography-mass...
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Investigation of vortex assisted magnetic deep eutectic solvent based dispersive liquid–liquid microextraction for separation and determination of vanadium from water and food matrices: Multivariate analysis
PublikacjaA new and simple vortex assisted magnetic deep eutectic solvent dispersive liquid–liquid microextraction procedure (VA-MDES-DLLME) was developed for the determination of vanadium (V) in food and water samples by flame atomic absorption spectrometry (FAAS). In the extraction medium, a bis(acetylpivalylmethane) ethylenediimine (H2APM2en) was used for the complexation of V(V) in sample solution at pH 6. The VA-MDES-DLLME was optimized...
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A Comparative Quantitative Structure-Retention Relationships Study for Lipophilicity Determination of Compounds with a Phenanthrene Skeleton on Cyano-, Reversed Phase-, and Normal Phase-Thin Layer Chromatography Stationary Phases
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Correction to: Chromium‑based metal organic framework for pipette tip micro‑solid phase extraction: an effective approach for determination of methyl and propyl parabens in wastewater and shampoo samples
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PCN-222 metal–organic framework: a selective and highly efficient sorbent for the extraction of aspartame from gum, juice, and diet soft drink before its spectrophotometric determination
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Determination of tributylotin (TBT) in marine sediment using pressurised liquid extraction-gas chromatography-isotope dilution mass spectrometry (PLE-GC-IDMS) with a hexane-tropolone mixture
PublikacjaOpracowano metodę oznaczania zawartości tributylocyny w próbkach osadu morskiego. Na etapie izolacji zastosowano technikę przyspieszonej ekstrakcji za pomocą roztworu tropolonu w heksanie.Na etapie oznaczeń końcowych wykorzystano technikę chromatografii gazowej, stosując metodę spektrometrii mas rozcieńczenia izotopowego. Wyznaczono parametry walidacyjne opracowanej metody: granicę wykrywalności, precyzję, poprawność i niepewność.
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Interference-Free Determination of Trace Copper in Freshly Ripened Honeys by Flame Atomic Absorption Spectrometry Following a Preconcentration by Solid-Phase Extraction and a Two-Step Elution Process
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Determination of tributyltin (TBT) in marine sediment using pressurised liquid extraction–gas chromatography–isotope dilution mass spectrometry (PLE–GC–IDMS) with a hexane–tropolone mixture
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Determination of phenol biodegradation pathways in three psychrotolerant yeasts, Candida subhashii A011, Candida oregonensis B021 and Schizoblastosporion starkeyi-henricii L012, isolated from Rucianka peatland
PublikacjaIn this study, three psychrotolerant phenol-degrading yeast strains Candida subhashii (strain A011), Candida oregonenis (strain B021) and Schizoblastosporion starkeyi-henricii (strain L012) isolated from Rucianka peatland were examined to determine which alternative metabolic pathway for phenol biodegradation is used by these microorganisms. All yeast strains were cultivated in minimal salt medium supplemented with phenol at 500,...
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Uncertainty of Postmortem Time Estimation Based on Potassium Ion Determination in Vitreous Humor Using Potentiometric Ion-Selective Electrode and Microwave-Induced Plasma with Optical Emission Spectrometry Methods
PublikacjaThere is a need for a reliable and independent evaluation and confirmation of the post-mortem interval (PMI) based on objective factors other than only postmortem changes or temperature measurements. Estimating the PMI by examining the concentration of potassium ions in the vitreous humor (VH) has a tradition in forensic toxicology dating back to the mid-20th century. So far, the methods for determining the presence of potassium...
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Magnetic hydrophobic deep eutectic solvents for orbital shaker-assisted dispersive liquid-liquid microextraction (MAGDES-OS-DLLME) - determination of nickel and copper in food and water samples by FAAS
PublikacjaIn this work, a cheap and widely applicable dispersive liquid-liquid microextraction (DLLME) method was developed for the extraction of Ni(II) and Cu(II) from water and food samples and analysis using flame atomic absorption spectrometry. DLLME was assisted by orbital shaker, while ferrofluid as an extractant was based on deep eutectic solvent (DES). This ferrofluid was made of hydrophobic DES (hDES), composed of lauric acid and...
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The presence of polycyclic aromatic hydrocarbons in disposable baby diapers: A facile determination method via salting-out assisted liquid-liquid extraction coupled with gas chromatography-mass spectrometry
PublikacjaIn this paper we demonstrate the development of the extraction procedure of polycyclic aromatic hy- drocarbons from baby diapers along with their quantification by gas chromatography-mass spectrometry. Apart from covering plastic foil, disposable baby diapers contain sorbents intended to absorb urine and feces. A hygroscopic, adsorptive, and tough-to-homogenize fibrous sorbent, represents an analytical chal- lenge to analytical...
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Simultaneous determination of droxidopa and carbidopa by carbon paste electrode functionalized with NiFe2O4 nanoparticle and 2-(4-ferrocenyl-[1,2,3]triazol-1-yl)-1-(naphthalen-2-yl) ethanone
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Application of gas flow headspace liquid phase micro extraction coupled with gas chromatography-mass spectrometry for determination of 4-methylimidazole in food samples employing experimental design optimization
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The Mesoporous Porphyrinic Zirconium Metal-Organic Framework for Pipette-Tip Solid-Phase Extraction of Mercury from Fish Samples Followed by Cold Vapor Atomic Absorption Spectrometric Determination
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Coupling of cold vapor generation with an atmospheric pressure glow microdischarge sustained between a miniature flow helium jet and a flowing liquid cathode for the determination of mercury by optical emission spectrometry
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Application of Alanine Scanning to Determination of Amino Acids Essential for Peptide Adsorption at the Solid/Solution Interface and Binding to the Receptor: Surface-Enhanced Raman/Infrared Spectroscopy versus Bioactivity Assays
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Determination of the effective concentration of oxyteracycline solutions on the inhibition of bioluminescence of Vibrio fischeri (Microtox)
Dane BadawczeIn this study an attempt was made to determine the effective concentration for oxytetracycline solutions on the inhibition of bioluminescence of Vibrio fischeri (Microtox).
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Determination of the effective concentration of ketoprofen against the germination of Sorghum bicolor (sorghum) seeds
Dane BadawczeResearch data includes an attempt to determine the effective concentration of ketoprofen that inhibits germination of Sorghum bicolor (sorghum) seeds.
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SEM and Raman studies B:CNWs and BDD electrode used for electrochemical paraquat determination
Dane BadawczeThe dataset contains the scanning electron micrographs (SEM) and Raman spectra of B:CNWs and BDD samples deposited by MW-PECVD. SEM was used to characterise the morphology of BDD and B:CNW. In contrast, RAMAN was used to reveal the main differences in the crystalline structure of BDD and B:CNWs.
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Rapid and simple multi-analyte LC–MS/MS method for the determination of benzodiazepines and Z-hypnotic drugs in blood samples: Development, validation and application based on three years of toxicological analyses
PublikacjaBenzodiazepines (BZDs) and Z-drugs have been particularly important treatments for sleeping and anxiety disorders for many years. However, recently, a number of new benzodiazepines (named designer benzodiazepines, DBZDs) were synthesised, but some of them have never been used in the clinic; they reached the black drug market as new psychoactive substances and are used for recreational purposes. The abuse of these substances has...
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Application of Box-Behnken design in response surface methodology for the molecularly imprinted polymer pipette-tip solid phase extraction of methyl red from seawater samples and its determination by spectrophotometery
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Synthesis, characterization and application of a zirconium-based MOF-808 functionalized with isonicotinic acid for fast and efficient solid phase extraction of uranium(VI) from wastewater prior to its spectrophotometric determination
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Separation and determination of ciprofloxacin in seawater, human blood plasma and tablet samples using molecularly imprinted polymer pipette‐tip solid phase extraction and its optimization by response surface methodology
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