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Wyniki wyszukiwania dla: reversed phase high-pressure liquid chromatography (rphplc)
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Method for the determination of carboxylic acids in industrial effluents using dispersive liquid-liquid microextraction with injection port derivatization gas chromatography–mass spectrometry
PublikacjaThe paper presents a new method for the determination of 15 carboxylic acids in samples of postoxidative effluents from the production of petroleum bitumens using ion-pair dispersive liquid-liquid microextraction and gas chromatography coupled to mass spectrometry with injection port derivatization. Several parameters related to the extraction and derivatization efficiency were optimized. Under optimized experimental conditions,the...
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Silica-Based Ionogels: Nanoconfined Ionic Liquid-Rich Fibers for Headspace Solid-Phase Microextraction Coupled with Gas Chromatography–Barrier Discharge Ionization Detection
PublikacjaIn this work, hybrid silica-based materials with immobilized ionic liquids (ILs) were prepared by sol–gel technology and evaluated as solid-phase microextraction (SPME) fiber coatings. High loadings of the IL 1-methyl-3-butylimidazolium bis(trifluoromethylsulfonyl)imide ([C4MIM][TFSI]) were confined within the hybrid network. Coatings composition and morphology were evaluated using scanning electron microscopy and energy dispersive...
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Retention time and peak width in the combined pH/organic modifier gradient high performance liquid chromatography
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Effect of sample-preparation methods on the quantification of selected flavonoids in plant materials by high performance liquid chromatography
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Investigations on mixture preparation for two phase adiabatic pressure drop of R134a flowing in 5 mm diameter channel
PublikacjaThe article presents detailed two-phase adiabatic pressure drops data for refrigerant R134a. Study cases have been set for a mass flux varying from 200 to 400 kg/m2 s, at the saturation temperature of 19.4 ◦C. Obtained experimental data was compared with the available correlations from the literature for the frictional pressure drop during adiabatic flow. Influence of mixture preparation on pressure drop was investigated, for...
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Badania nad doborem najkorzystniejszego składu eluentu do rozdzielenia metabolitów wtórnych z grupy naftochinonów i flawonoidów z zastosowaniem chromatografii planarnej w normalnym i odwróconym układzie faz = A research on the composition of the eluent for separation of plant metabolities by reversed phase planar chromatography
PublikacjaIn the paper the results of separation of plant extracts by RP-TLC with different composition of the eluents are presented. Analysis of retention data allowed to select components of the eluent with favorable retention parameters, which can be used in the future for separation of this type of plant extracts by column liquid chromatography techniques.
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Dispersive liquid-liquid microextraction combined with gas chromatography–mass spectrometry for in situ determination of biogenic amines in meat: Estimation of meat's freshness
PublikacjaA dispersive liquid-liquid microextraction (DLLME) gas chromatography–mass spectrometry (GC–MS) technique was developed for the determination of selected biogenic amines (BAs) in samples of poultry, pork and beef. Prior to the extraction process, an appropriate volume of sodium hydroxide solution was added to each of the portioned samples. Next, samples were homogenized, centrifuged and finally sonicated at an increased temperature....
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A natural deep eutectic solvent - protonated L-proline-xylitol - based stationary phase for gas chromatography
PublikacjaThe paper presents a new kind of stationary phase for gas chromatography based on deep eutectic solvents (DES) in the form of a mixture of L-proline (protonated with hydrochloric acid) as a hydrogen bond acceptor (HBA) and xylitol as a hydrogen bond donor (HBD) in a molar ratio of HBA:HBD 5:1. DES immobilized on a silanized chromatographic support was tested by gas chromatography (GC) in order to determine its resolving power for...
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Evaluation of the High-Pressure Gas Transmission Network Impact for Environmental - Construction Phase and Network Operation
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Signal Processing in the Investigation of Two-phase Liquid-gas Flow by Gamma-ray Absorption
Publikacjan this paper, the use of the gamma-absorption method applied in the investigation of the two-phase liquid-gas flow in the pipeline is described. An example of its application to the air transported by water in a horizontal pipeline is evaluated. In the measurements, Am-241 radioactive sources and probes with Nal (Tl) scintillation crystals have been used. The signals from the radiometric set were used to determine the velocity...
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An evaluation of sucrose as a possible contaminant in e-liquids for electronic cigarettes by hydrophilic interaction liquid chromatography–tandem mass spectrometry
PublikacjaThe influence of sucrose combustion products on smoking and nicotine addiction is still controversial because the presence of the sucrose may be treated as a source of aldehydes and organic acids. In e-liquids used as refills for electronic cigarettes, which are made primarily of poly(propylene glycol), glycerine and ethanol, sucrose may be present at trace levels, and its impact on mainstream smoke formation, and hence on human...
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High Pressure Luminescence of Cr-Related Centers in (3CaO-Ga 2 O 3 -3GeO 2 ) Glasses
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Determination of isoprostanes in exhaled breath condensate samples by liquid chromatography coupled with tandem mass spectrometry
PublikacjaOxidative stress (OS) is a state of imbalance between continuously generating reactive oxygen species (ROS) during normal cell metabolism and mechanism of detoxifying oxygen radicals through a network of antioxidative enzymes. Isoprostanes are prostaglandin -like substances that are produced in vivo primarily by free radical-induced peroxidation of arachidonic acid. The measurement of isoprostanes in biological fluids and/or tissue...
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Partition coefficients of selected environmentally important volatile organic compounds determined by gas - liquid chromatography with polydimethylsiloxane stationary phase
PublikacjaPrzedstawiono wartości współczynników podziału (stałych podziału) 14 lotnych związków organicznych istotnych dla stanu środowiska (często oznaczanych w powietrzu w pomieszczeniach zamkniętych) między fazą gazową (N2) a ciekłą (PDMS). Wyznaczano je dwiema technikami (izotermiczną i z liniowo programowanym wzrostem temperatury). Dowiedziono, że istnieje możliwość wyznaczania współczynników podziału techniką LTPRI w oparciu o skalę...
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Determination of tocopherols and tocotrienols in human breast adipose tissue with the use of high performance liquid chromatography-fluorescence detection
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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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An in situ derivatization – dispersive liquid–liquid microextraction combined with gas-chromatography – mass spectrometry for determining biogenic amines in home-made fermented alcoholic drinks
PublikacjaA novel dispersive liquid–liquid microextraction (DLLME) gas chromatography mass-spectrometry(GC–MS) method was developed for the determination of 13 biogenic amines in home-made wine sam-ples. The method allows to simultaneous extraction and derivatization of the amines providing a simpleand fast mode of extract enrichment. During the study, two different procedures were examined. Sta-tistical analysis was performed to choose...
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Application of dispersive liquid-liquid microextraction and gas chromatography with mass spectrometry for the determination of oxygenated volatile organic compounds in effluents from the production of petroleum bitumen
PublikacjaWepresent a new procedure for the determination of oxygenated volatile organic compounds in samples of postoxidative effluents from the production of petroleum bitumens using dispersive liquid–liquid microextraction and gas chromatography with mass spectrometry. The eight extraction parameters were optimized for 43 oxygenated volatile organic compounds. The detection limits obtained ranged from 0.07 to 0.82 g/mL for most of the...
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Separation of toluene from gas phase using supported imidazolium ionic liquid membrane
PublikacjaInvestigation on utilization of supported ionic liquids membranes for hydrocarbon separation from the gas phase was performed. Properties of membrane phase, wettability of supports, swelling effects and solubility of toluene were taken into account. Toluene permeation rates were significantly higher than those of pure nitrogen, the selectivity in a range of 17–341 was satisfying for separation. Despite the increase of viscosity...
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Troubleshooting of the determination of bisphenol A at ultra-trace levels by liquid chromatography and tandem mass spectrometry
PublikacjaDetermination of trace amounts of bisphenol A (BPA) may cause problems mainly related to the presence of BPA in solvents (even in LC-MS grade), laboratory vessels, and plastic equipment used for sample preparation. Variable and sometimes significant amounts of BPA present in the background cause problems in obtaining good repeatability of measurements at the ultra-trace levels. Such observations (i.e., poor repeatability of results)...
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Measurement of activity coefficients at infinite dilution of organic solutes in the ionic liquid 1-hexyl-1,4-diaza[2.2.2]bicyclooctanium bis(trifluoromethylsulfonyl)imide using gas–liquid chromatography
PublikacjaBased on gas–liquid chromatography (GLC) retention data, activity coefficients at infinite dilution of 39 different solutes in the ionic liquid 1-hexyl-1,4-diaza[2.2.2]bicyclooctanium bis(trifluoromethylsulfonyl)imide ([HDABCO][NTf2]) have been determined. Measurements covered a broad range of types of organic solutes including alkanes, alcohols, ketones, benzene derivatives and McReynold’s compounds. Activity coefficients were...
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Determination of Pesticide Residues in Honeybees using Modified QUEChERS Sample Work-Up and Liquid Chromatography-Tandem Mass Spectrometry
PublikacjaIncreasing emissions of chemical compounds to the environment, especially of pesticides, is one of factors that may explain present honeybee colony losses. In this work, an analytical method employing liquid chromatography-tandem mass spectrometry (LC-MS/MS) was optimized for the simultaneous screening of 19 pesticides which have not been yet determined in honeybee samples from northern Poland (Pomerania). The sample preparation,...
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Development of a liquid chromatography–tandem mass spectrometryprocedure for determination of endocrine disrupting compounds infish from Mediterranean rivers
PublikacjaA new, sensitive and rapid method based on QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe)approach followed by ultra high performance liquid chromatography coupled with tandem mass spec-trometry (UHPLC–MS/MS) was developed for the determination of nineteen endocrine disruptors (EDCs)and related compounds belonging to different classes in various fish species. Matrix effect on the analyti-cal performance was evaluated,...
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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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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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Simulation of fluid structure interaction in a novel design of high pressure axial piston pump
PublikacjaA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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A nontargeted approach to determine the authenticity of Ginkgo biloba L. plant materials and dried leaf extracts by liquid chromatography-high-resolution mass spectrometry (LC-HRMS) and chemometrics
PublikacjaThe lack of stringent regulations regarding raw materials for herbal supplements used for medicinal purposes has been a constant challenge in the industry. Ginkgo biloba L. leaf extracts attract consumers because of the supposed positive effect on mental performance and memory. Supplements are produced using dried leaf materials and standardized leaf extracts such as EGb 761. Adulteration of Ginkgo biloba L. plants and extracts...
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A headspace solid-phase microextraction method development and itsapplication in the determination of volatiles in honeys by gas chromatography
PublikacjaThe first part of the paper presents the detailed optimisation of all steps of the determination procedureof volatiles from Polish honeys by headspace solid-phase microextraction (HS-SPME) as the sample preparationmethod and gas chromatography/mass spectrometry (GC-MS) as the method of final determination.The methodology of semi-quantative analysis allowed the isolation and identification of volatile fractioncompounds from popular...
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Sensitive simultaneous determination of 19 fluorobenzoic acids in saline waters by solid-phase extraction and liquid chromatography–tandem mass spectrometry
PublikacjaA solid-phase extraction (SPE) procedure using C18 stationary phase was optimized for the preconcentration of 19 fluorinated derivatives of benzoic acid (FBA): mono-, di-, tri-, and tetrafluorosubstituted in the ring, trifluoromethylbenzoic acid and 3,5-bistrifluoromethyl benzoic acid from undiluted salt-rich (>20%) reservoir waters. Quantitative (>90%) retention/elution of 16 out of 19 analyte compounds was achieved allowing a...
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Determination of Nine Intense Sweeteners in Foodstuffs by High-Performance Liquid Chromatography and Evaporative Light-Scattering Detection: Interlaboratory Study
PublikacjaW pracy przedstawiono wyniki badań międzylaboratoryjnych, opracowanej wcześniej metody jednoczesnego oznaczania dziewięciu słodzików o wysokiej mocy w produktach żywnościowych. W badaniach wzięło udział siedem laboratoriów (Belgia, Niemcy, Portugalia). W rezultacie dowiedziono, iż opracowana metoda umożliwia uzyskanie dokładnych, powtarzalnych i odtwarzalnych wyników analiz dla wszystkich badanych słodzików i typów żywności.
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A Fast and Validated Method for the Determination of Malondialdehyde in Fish Liver Using High-Performance Liquid Chromatography with a Photodiode Array Detector
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Application of multivariate mathematical-statistical methods to compare reversed-phase thin-layer and liquid chromatographic behaviour of tetrazolium salts in Quantitative Structure-Retention Relationships (QSRR) studies
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High-performance liquid chromatography of di- and trisubstituted aromatic positional isomers on 1,3-alternate 25,27-dipropoxy-26,28-bis-[3-propyloxy]-calix[4]arene-bonded silica gel stationary phase.
PublikacjaOtrzymano nową fazę stacjonarną na bazie dipropyloksy pochodnej kaliks[4]arenu w konformacji 1,3-naprzemianległej chemicznie związaną z żelem krzemionkowym. Przeprowadzono badanie selektywności i sprawności tej fazy w rozdzielaniu izomerów konstytucyjnych benzenu. Zaprezentowano wyniki badania wpływu warunków chromatograficznych (pH fazy ruchomej, temperatura, stężenie modyfikatora organicznego) na zdolność rodzielczą tej nowej...
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Uncertainty of antioxidant profiling in complex mixtures using liquid chromatography involving post-column derivatisation
PublikacjaThe main goal of this paper is to discuss the problems associated with antioxidant profiling in complex samples using a high-throughput HPLC system coupled with post-column derivatisation reactor. Based on the experimental data reported in the literature, we demonstrated that improper optimisation of temperature and/or pH assay conditions performed using an on-line derivatisation reactor may substantially change the antioxidant...
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Simulation of fluid structure interaction in a novel design of high pressure axial piston hydraulic pump
PublikacjaA novel type of an axial, piston-driven high pressure hydraulic pump with variable capacity marks a significant improvement in the area of the hydraulic machinery design. Total discharge from hydrostatic forces eliminates a need for a servomechanism, thus simplifying operation, reducing weight and introducing the possibility of the pump displacement control by computer. PWK-type pumps, invented in the Gdansk University of Technology,...
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Free silanols and ionic liquids as their suppressors in liquid chromatography
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Can high hydrostatic pressure processing be the best way to preserve human milk?
PublikacjaBreastfeeding is one of the most important factors influencing proper child development. When a mother cannot breastfeed, the best alternative, especially for feeding premature infants, is to then use of human milk (HM) which has been collected, preserved and stored in Human Milk Banks (HMB). Scope and approach: In this review, the impact of some stages of the management of HM in HMB on its final biological value and microbiological...
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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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Analysis of serum homocysteine in the laboratory practice - comparison of the direct chemiluminescence immunoassay and high performance liquid chromatography coupled with fluorescent detection
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Molecularly imprinted stir bar sorptive extraction coupled with high-performance liquid chromatography for trace analysis of naphthalene sulfonates in seawater
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Procedure for and results of simultaneous determination of aromatic hydrocarbons and fatty acids methyl esters in diesel fuels by high performance liquid chromatography
PublikacjaW pracy przedstawiono taki sposób modyfikacji metody EN-12916 /ASTM D-6591, który zapewnia jednoczesne oznaczenie poszczególnych grup węglowodorów aromatycznych, całkowitej zawartości węglowodorów poliaromatycznych oraz zawartości FAME w oleju napędowym. Stosuje się nadal detektor refraktometryczny i elucję n-heptanem, jednak przepływ zwrotny eluentu jest wykonywany po elucji policyklicznych węglowodorów aromatycznych. Dodatkowo...
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Impact of high-pressure processing on the bioactive compounds of milk - A comprehensive review
PublikacjaHigh-pressure processing (HPP) is a promising alternative to thermal pasteurization. Recent studies highlighted the effectivity of HPP (400–600 MPa and exposure times of 1–5 min) in reducing pathogenic microflora for up to 5 logs. Analysis of modern scientific sources has shown that pressure affects the main components of milk including fat globules, lactose, casein micelles. The behavior of whey proteins under HPP is very important...
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The role of fluids in high-pressure polymorphism of drugs: different behaviour of β-chlorpropamide in different inert gas and liquid media
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The effect of high pressure on formation of volatile amines in minced meat of cod (Gadus morhua)
PublikacjaThe effects of high pressure at subzero temperature (193 MPa, at −20 °C) on inactivation of natural microflora of cod meat and degradation of trimethylamine oxide (TMAO) to trimethylamine (TMA) during refrigerated storage and to dimethylamine (DMA) and formaldehyde (FA) during frozen storage were investigated. The content of TMA, DMA and FA in cod meat did not change immediately after pressure treatment. During 40 days of frozen...
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Energetics of formation and stability in high pressure steam of barium lanthanide cobaltite double perovskites
PublikacjaThis study concerns energetics of formation and the stability in high water partial pressure of BaLnCo2O6−δ, (Ln = La, Pr, Nd, and Gd) (BLnC) and BaGd1−xLaxCo2O6−δ, where x = 0.2, 0.5, and 0.7 (BGLC) double perovskite cobaltites. Those materials are extensively studied due to their potential applications as a positrode in electrochemical devices. Therefore, their stability under such conditions is a key issue. All investigated...
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Comparison of noise reduction methods in radiometric correlation measurements of two-phase liquid-gas flows
PublikacjaTwo-phase liquid-gas flows occur frequently in the mining, energy, chemical, and petrochemical industries. One of non-contact methods used to analyse these flows is the gamma ray absorption method. However, the signals received from radiation detectors contain a significant stochastic noise, which makes them difficult to analyse. The article describes four methods of noise reduction in cross-correlation measurements of water-air...
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First deep eutectic solvent-based (DES) stationary phase for gas chromatography and future perspectives for DES application in separation techniques
PublikacjaThe paper presents the first application of deep eutectic solvents (DES) as stationary phases for gas chromatography. DES obtained by mixing tetrabutylammonium chloride (TBAC) as a hydrogen bond acceptor (HBA) with heptadecanoic acid being a hydrogen bond donor (HBD) in a mole ratio of HBA:HBD equal to 1:2 was characterized by its ability to separate volatile organic compounds (VOCs). The Rohrschneider – McReynolds constants determined...
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Effectiveness of toluene separation from gas phase using supported ammonium ionic liquid membrane
PublikacjaAmmonium ionic liquids (ILs) are relatively cheap in synthesis and environmentally benign and despite that they have been very rarely used in gas separation. In this research we used several ammonium ILs as liquid membranes for removal of residual toluene from gas phase. Ionic liquids used in this study were composed of bis(trifluoromethylsulfonyl)imide anion [Tf2N] and trimethylbutylammonium [N1114], trietylbutylammonium [N2224],...
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Pressure effects on the electronic structure and superconductivity of (TaNb)0.67(HfZrTi)0.33 high entropy alloy
PublikacjaEffects of pressure on the electronic structure, electron-phonon interaction, and superconductivity of the high entropy alloy ( TaNb ) 0.67 ( HfZrTi ) 0.33 are studied in the pressure range 0–100 GPa. The electronic structure is calculated using the Korringa-Kohn-Rostoker method with the coherent potential approximation. Effects of pressure on the lattice dynamics are simulated using the Debye-Grüneisen model and the Grüneisen...
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Comprehensive determination of flavouring additives and nicotine in e-cigarette refill solutions. Part I: Liquid chromatography-tandem mass spectrometry analysis
PublikacjaLiquid chromatography-tandem mass spectrometry with electrospray ionization (HPLC-ESI–MS/MS) methods were developed for the simultaneous determination of 42 flavouring compounds and nicotine in liquids for e-cigarettes. The chromatographic separation was performed using an Ace® Ultracore™ SuperC18™ (100 × 2.1 mm, 2.5 μm) column in both acidic and alkaline pH conditions to separate all the compounds. A simple “dilute & shoot” approach...
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Application of high performance liquid chromatography with ultraviolet diode array detection and refractive index detection to the determination of class composition and the analysis of gasoline.
PublikacjaZaprezentowano nową metodę HPLC oznaczania składu grupowego benzyn i komponentów benzyn tj. oznaczania zawartości olefin, węglowodorów aromatycznych i parafinowo-naftenowych.
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Direct solid phase microextraction combined with gas chromatography – Mass spectrometry for the determination of biogenic amines in wine
PublikacjaA direct method based on immersion solid phase microextraction (DI-SPME) gas chromatography mass-spectrometry (GC-MS) was optimized and validated for the determination of 16 biogenic amines in Polish wines. In the analysis two internal standards were used: 1,7-diaminoheptane and bis-3-aminopropylamine. The method allows for simultaneous extraction and derivatization, providing a simple and fast mode of extraction and enrichment....
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Experimental study of flow boiling pressure drop and heat transfer of R1233zd(E) at moderate and high saturation temperatures
PublikacjaThe paper presents the results of experimental study of flow boiling of R1233zd(E) in minichannel at moderate and high saturation temperatures. The heat transfer coefficient and pressure drop were measured for flow boiling in a stainless steel tube with 2 mm inside diameter and a length of 300 mm. Experiment has been conducted for saturation temperatures ranging from 83 to 145 °C which corresponds to values of reduced pressures...
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Origin of the liquid-liquid phase transition for trans-1,2-dichloroethylene observed by IR spectroscopy
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Phenomenon of hydraulic jump formed on liquid layer by single-phase impinging liquid jet
PublikacjaPrzedstawiono analizę teoretyczną zjawiska uskoku hydraulicznego tworzonego przez uderzającą strugę. rezultaty analizy teoretycznej porównano z wynikami badań eksperymentalnych.
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Changes in enzymatic activity of fish and slaughter animals meat after high pressure treatment at subzero temperatures
PublikacjaThe aim of this study was to determine changes in the activity of proteolytic enzymes and transglutaminase of fish and mammal meat after pressurization at subzero temperatures. The activity was measured at the optimal pHs determined for enzymes from particular types of tested meat. It was found that increasing the pressure in the range of 60–193 MPa, did not change significantly the activity of acidic proteases of cod flesh, while...
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Low-temperature high-pressure cryogelation of nanooxides
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Influence of high pressure on Sr2SiO4:Eu2+ luminescence
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Energy levels in CaWO4:Tb3+ at high pressure
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High pressure evolution of YVO4:Pr3+luminescence
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High pressure luminescence spectra of CaMoO4:Pr3+
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Determination of antifreeze substances in the airport runoff waters by solid-phase microextraction and gas chromatography–mass spectrometry method
PublikacjaA new method has been developed for the determination of antifreeze agents such as ethylene glycol (EG), propylene glycol (PG), and diethylene glycol (DEG) in the samples of airport runoff water. The method is based on headspace solid–phase microextraction (HS–SPME) of target analytes, which is coupled with gas chromatography–mass spectrometry (GC–MS). Until now, there was a lack of appropriate methodology for collecting reliable...
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The simultaneous determination of hydrophobicity and dissociation constant by liquid chromatography–mass spectrometry
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Application of dispersive liquid-liquid microextraction for the determination of selected organochlorine pesticides in honey by gas chromatography - mass spectrometry
PublikacjaDispersive liquid-liquid microextraction (DLLME) is a rapid and easy technique that consumes minute amounts of organic solvents. In this work, we present chemometric study on optimization of DLLME parameters for the extraction of aldrin, endrin, lindane, alfa-endosulfan, 4,4'-DDT and its metabolites from honey matrix. Method quantification limits (MQLs) vary between 0.3 ng/g for 2,4'-DDE and 4,4'-DDE to 13.2 ng/g for alfa-endosulfan...
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High temperature monoclinic-to-tetragonal phase transition in magnesium doped lanthanum ortho-niobate
PublikacjaMagnesium doped lanthanum ortho-niobate (La0.98Mg0.02NbO4) was prepared by the molten salt synthesis method. X-ray diffraction and dilatometry methods were used to study high temperature behavior of the ceramic material. Special attention was paid to the phase transition between the monoclinic and tetragonal phases. The values of spontaneous strain on the basis of unit cell parameter, obtained by Rietveld refinement, have been...
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Application of Headspace Solid-phase Microextraction with Poly(1-vinyl-3- Hexylimidazolium Chloride) Polymeric Ionic Liquid Coating using GC - MS to Determine Volatile Fatty Acids in Dairy Wastewater
PublikacjaVolatile fatty acids were determined in this study using headspace solid-phase microextraction (HS-SPME) with a poly(1-vinyl-3-hexylimidazolium chloride) polymeric ionic liquid coated fiber followed by gas chromatography - mass spectrometry. Experimental parameters such as extraction time and temperature, sample volume as well as desorption time and temperature were optimized. Detection limits of the method were in the range of...
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Monolithic capsule phase microextraction prior to gas chromatography-mass spectrometry for the determination of organochlorine pesticides in environmental water samples
PublikacjaIn this study, a capsule phase microextraction (CPME) protocol followed by gas chromatography-mass spectrometry is proposed for the accurate and sensitive monitoring of organochlorine pesticides (OCPs) in environmental water samples. Different monolithic sol–gel encapsulated sorbents were compared and monolithic sol–gel poly(ethylene glycol)-based sorbent incorporated into porous microextraction capsules resulted in the highest...
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Fast, sensitive and reliable multi-residue method for routine determination of 34 pesticides from various chemical groups in water samples by using dispersive liquid – liquid microextraction coupled with gas chromatography – mass spectrometry
PublikacjaA simple and efficient dispersive liquid-liquid microextraction technique (DLLME) was developed by using a mixture of two solvents: 40 μL of tetrachlorethylene (extraction solvent) and 1.0 mL of methanol (disperser solvent), which was rapidly injected with a syringe into 10mL ofwater sample. Some important parameters affecting the extraction efficiency, such as type and volume of solvents, water sample volume, extraction time,...
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Rapid ion-exchange matrix removal for a decrease of detection limits in the analysis of salt-rich reservoir waters for fluorobenzoic acids by liquid chromatography coupled with tandem mass spectrometry
PublikacjaA matrix removal procedure with ion-exchange resin prior to analysis for 18 fluorinated benzoic acids (FBAs) tracers in saline (>25% salt) reservoir water was optimized. The elimination of >98% of salt and the simultaneous matrix sample cleanup allowed the direct analysis using the supernatant by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). This resulted in a gain in detection limits for most of the tracers...
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Dispersive solid-phase extraction using multi-walled carbon nanotubes combined with liquid chromatography–mass spectrometry for the analysis of β-blockers: Experimental and theoretical studies
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Experimental and comparative study on the two-phase pressure drop of air-water mixture in U-bend and straight pipe annuli
PublikacjaIn this paper, the experimental and theoretical analysis of pressure drop in singlephase and two phase-flow were presented for straight and U-bend smooth tube annulus and tube annulus with wire coil insert. Experiments for various boundary conditions were performed. In case of U-tube and straight tube with and without turbulator, tests were made for the water-water and air-water systems. The study covered a wide measuring range,...
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High-Energy-Low-Temperature Technologies for the Synthesis of Nanoparticles: Microwaves and High Pressure
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Chemically Bonded Silica Stationary Phases: Synthesis, Physicochemical Characterization, and Molecular Mechanism of Reversed-Phase HPLC Retention
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Determination of fluoride as fluorosilane derivative using reversed-phase HPLC with UV detection for determination of total organic fluorine
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Physical properties of homogeneous TiO2 films prepared by high power impulse magnetron sputtering as a function of crystallographic phase and nanostructure
PublikacjaOptical, photo-electrochemical, crystallographic and morphological properties of TiO2 thin films prepared by high power impulse magnetron sputtering at low substrate temperatures (<65 ◦C) without post-deposition thermal annealing are studied. The film composition-anatase, rutile or amorphous TiO2-is adjusted by the pressure (p ∼ 0.75-15 Pa) in the deposition chamber. The different crystallographic phases were determined with grazing...
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The effect of high pressure at subzero temperature on proteins solubility, drip loss and texture of fish (cod and salmon) and mammal’s (pork and beef) meat
PublikacjaOne of the possibilities of using high pressure technique in inactivation of microorganism is conducting this process at subzero temperature. However, for its practical application in meat preservation the appropriate properties of meat should be kept. Therefore, the aim of this work was to examine the effect of pressure at subzero temperature (without freezing of water) on proteins and texture of mammal’s and cold-adapted fish...
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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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General practitioners ignore high normal blood pressure
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Effect of high pressure of selected bacteria at subzero temperature
PublikacjaCelem pracy było określenie przeżywalności wybranych bakterii gramdodatnich i gramujemnych poddanych działaniu podwyższonego ciśnienia w zakresie od 60 do 193 MPa w ujemnej temperaturze. Wrażliwość bakterii na zwiększone ciśnienie zależy od fazy wzrostu w jakiej się one znajdują. Z reguły bakterie gramdodatnie są bardziej odporne na ciśnienie niż bakterie gramujemne. Wykazano, że różnice w odporności pojawiają się nie tylko pomiędzy...
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High pressure effect on charge transfer transition in Y2O2S:Eu3+
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Luminescence properties of MgF2:Yb2+ at high hydrostatic pressure
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High-pressure luminescence ofCr3+-dopedCaO−Ga2O3−GeO2glasses
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High pressure luminescence of Y V O4:Pr3+
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High Pressure Spectroscopy of Ce Doped Yag Crystal
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Comparison of mouse plasma and brain tissue homogenate sample pretreatment methods prior to high-performance liquid chromatography for a new 1,2,4-triazole derivative with anticonvulsant activity
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Stabilities of bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and their derivatives under controlled conditions analyzed using liquid chromatography coupled with tandem mass spectrometry
PublikacjaBisphenol A diglycidyl ether (BADGE), bisphenol F diglycydyl ether (BFDGE), and their related compounds are widely used as precursors in production of epoxy resins. The high reactivity of these compounds makes the development of analytical methodologies that ensure appropriate metrological accuracy crucial. Consequently, we aimed to determine whether and to what extent the composition of the solution and storage conditions affect...
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Spectroscopic study of atmospheric pressure 915 MHz microwave plasma at high argon flow rate
PublikacjaIn this paper results of optical emission spectroscopic (OES) study of atmospheric pressure microwave 915 MHz argon plasma are presented. The plasma was generated in microwave plasma source (MPS) cavity- resonant type. The aim of research was determination of electron excitation temperature Texc gas temperature Tg and electron number density ne. All experimental tests were performed with a gas flow rate of 100 and 200 l/min and...
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Gaoya Wuli Xuebao/Chinese Journal of High Pressure Physics
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Review of High Pressure Science and Technology/Koatsuryoku No Kagaku To Gijutsu
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Data points of structures of R1233zd(E) flowing in a circular minichannel at low, medium and high values of saturation pressure
Dane BadawczeDatabase present structures of two-phase flow of R1233zd(E) in 3 mm vertical channel. Database contains datapoints which contain information of reduced pressure (ratio of saturation pressure and critical pressure), quality and mass velocity. 4 two phase structures are distinguished: bubbly flow, slug flow, intermittent flow and annular flow.
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The high impedance measuring probe for gain-phase analysers.
PublikacjaAutorzy opracowali tanią sondę pomiarową przeznaczoną do pracy z analizatorami gain-phase jak Solartron 1260 Impedance/Gain-phase Analyser, 1255 Frequency Response Analyser (FRA) lub starszymi wersjami 1250, 1253. Przedstawiona architektura sondy wyznacza jej parametry metrologiczne. Pomiary możliwe są w 8 zakresach obejmujących wartości 100ohm<|Zx|<100Gohm w szerokim zakresie częstotliwości 10uHz-1MHz. Obwód wejściowy sondy pozwala...
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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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Thermotropic Biaxial Nematic Phase in Liquid Crystalline Organo-Siloxane Tetrapodes
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Mechanism of a Four-Phase Liquid Membrane Oscillator Containing Hexadecyltrimethylammonium Bromide
PublikacjaBadano zachowanie nitrometanowego oscylatora z membraną ciekłą zawierającego kationowy surfaktant. Początkowo układ składał się z trzech faz: wodnej donorowej zawierającej surfaktant i etanol, membrany ciekłej (kwas pikrynowy w nitrometanie) oraz fazy wodnej akceptorowej zawierającej sacharozę. Podczas procesu oscylacyjnego wytwarzała się nowa fazą X między membraną ciekłą, a fazą akceptorową. Stwierdzono oscylacje różnicy potencjału...
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Stability of liquid film formed due to impingement of a two-phase jet
PublikacjaPrzedstawiono analizę teoretyczną i badania eksperymentalne zjawiska rozrywania się warstwy cieczy powstałej na powierzchni ciała stałego z uderzającej strugi.
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High-performance liquid chromatography thermodynamic study of new potential antiepileptic compounds on a cholesterol column using isocratic elution with methanol/water and acetonitrile/water eluent systems
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Pressure-induced phase transition in LiLuF4:Pr3+investigated by an optical technique
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Rapid and Green Separation of Mono- and Diesters of Monochloropropanediols by Ultrahigh Performance Supercritical Fluid Chromatography–Mass Spectrometry Using Neat Carbon Dioxide as a Mobile Phase
PublikacjaThis study demonstrates the effect of column selectivity and density of supercritical carbon dioxide (SC-CO2) on the separation of monochloropropanediol (MCPD) esters, known as food toxicants, using SC-CO2 without addition of cosolvent in ultrahigh performance supercritical fluid chromatography–mass spectrometry (UHPSFC-MS). This study shows that over 20 2-monochloropropanediol (2-MCPD) and 3-monochloropropanediol (3-MCPD) mono-...
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Solid phase microextraction–comprehensive twodimensional gas chromatography–time-of-flight mass spectrometry: a new tool for determining PAHs in airport runoff water samples
Publikacjafundamental aspect of airport operations is the pollution caused by airport runoff waters. Polycyclic aromatic hydrocarbons (PAHs) are one of the most important groups of xenobiotics which are commonly found in runoff water originating from airports. Only very limited data on the analysis of airport runoff water have been published until now. Therefore, a reliable and accurate analytical method based on headspace solid-phase microextraction...
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Liquid chromatography tandem mass spectrometry study of urinary nucleosides as potential cancer markers
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