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Wyniki wyszukiwania dla: reversed phase high-pressure liquid chromatography (rphplc)
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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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Origin of the liquid-liquid phase transition for trans-1,2-dichloroethylene observed by IR spectroscopy
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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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A gap waveguide-based mechanically reconfigurable phase shifter for high-power Ku-band applications
PublikacjaThis paper presents a novel design of a low-loss, reconfgurable broadband phase shifter based on groove gap waveguide (GGW) technology. The proposed phase shifter consists of a folded GGW and three bends with a few pins forming the GGW and one bend attached to a movable plate. This movable plate allows for adjustments to the folded waveguide length, consequently altering the phase of electromagnetic waves. The advantage of GGW...
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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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Determination of five sulfonamides in medicated feedingstuffs by liquid chromatography with ultraviolet detection
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Amphenicols stability in medicated feed – development and validation of liquid chromatography method
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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 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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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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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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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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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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High pressure impact on changes in potato starch granules
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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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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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General practitioners ignore high normal blood pressure
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Micellar liquid chromatography for lipophilicity determination of new biologically active 1,3‐purinodiones
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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 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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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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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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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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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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Thermotropic Biaxial Nematic Phase in Liquid Crystalline Organo-Siloxane Tetrapodes
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Pressure-induced phase transition in LiLuF4:Pr3+investigated by an optical technique
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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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Spectroscopic properties of high-temperature sintered SrS:0.05%Ce3+ under high hydrostatic pressure
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Effect of the working liquid compressibility on the picture of volumetric and mechanical losses in a high pressure displacement pump used in a hydrostatic drive Part II Mechanical losses in a pump
PublikacjaŚciśliwość cieczy roboczej może znacząco zmienić wartości i proporcje współczynników strat objętościowych i mechanicznych w pompie wyporowej zastosowanej w układzie napędu hydrostatycznego. Wpływ ten jest szczególnie widoczny w trakcie pracy pod wysokim ciśnieniem a także wówczas, gdy występuje zapowietrzenie cieczy roboczej. W części II przedstawiono model matematyczny momentu strat mechanicznych w pompie oraz jego laboratoryjną...
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Treatment of high blood pressure in elderly and octogenarians: European Society of Hypertension statement on blood pressure targets
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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-...