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Synthesis, structure and physical properties of new intermetallic spin glass-like compounds RE2PdGe3 (RE = Tb and Dy)
PublikacjaNew intermetallic compounds Tb2Pd1.25Ge2.75 and Dy2Pd1.25Ge2.75 have been synthesized using the arc-melting method. The crystallographic structure and magnetic, electronic transport, and thermal properties are reported. The crystal structure obtained from powder x-ray diffraction analysis suggests that these compounds crystallize in the AlB2-type structure (space group P6/mmm, no. 191) with lattice parameters a = 4.228 53(5)/4.230 54...
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Intermetallic disordered magnet Gd2Pt1.1Ge2.9 and its relation to other AlB2 -type compounds
PublikacjaThe intermetallic germanide Gd 2 Pt 1.1 Ge 2.9 was synthesized using an arc-melting method. The crystal structure was characterized using powder x-ray diffraction, revealing a disordered ternary AlB 2 -type structure (space group P 6 / m m m , No. 191) with lattice parameters a = 4.2092 ( 1 ) Å and c = 4.0546 ( 2 ) Å . Physical properties were investigated by magnetic susceptibility and heat capacity measurements, which...
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New matrix-free reference materials of volatile compounds - application of glass fibres as support materials for surface compounds
PublikacjaTechnika termicznego rozkładu związków powierzchniowych, znana od ponad dziesięciu lat, ulega ciągłym udoskonaleniom w celu otrzymywania coraz szerszej gamy wzorców analitycznych występujących na coraz niższych poziomach stężeń. Początkowo w roli nośnika stosowano żel krzemionkowy, który w trakcie dalszych faz rozwoju tej techniki zastąpiono kolejno szkłem porowatym, a następnie włóknem szklanym. W ostatnim czasie uproszczono układ...
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Recent trends in advanced oxidation process-based degradation of erythromycin: Pollution status, eco-toxicity and degradation mechanism in aquatic ecosystems
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Common methods for the chiral determination of amphetamine and related compounds II: Capillary electrophoresis and nuclear magnetic resonance
PublikacjaAmphetamine group and related ring-substituted substances are generally synthetic compounds, belonging to one of the most heavily abused drug groups in recent years. Some compounds in this class also originate from plants. Analysis of the enantiomers of AM-type compounds and metabolites is extremely important for a number of scientific disciplines. From studies of biological activity or mechanisms through determination of precursor...
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Photocatalytic degradation of acetaldehyde in high temperature reaction chamber
Dane BadawczeThis dataset contains chromatograms recorded during the decomposition of acetaldehyde in a high-temperature reaction chamber under UV irradiation using TiO2 (titanium dioxide) as photocatalysts. It includes data on the influence of flow rate, TiO2 (titanium dioxide) filling the entire reactor, a thin layer of TiO2 (titanium dioxide) supported on KBr...
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Separation of Volatile Oxygen-containing Organic Compounds by Gas Chromatography - selectivity comparison of different polarity stationary phases
PublikacjaThis paper present a results of the separation of 36 reference compounds belonging to the group of Volatile Oxygen-Containing Organic Compounds (OVOCs) using capillary gas chromatography with flame ionization detector (GC-FID) and three stationary phases of different polarity. A selectivity has been studied regarding to OVOCs and n -alkanes. The most useful for the separation of the group OVOCs is a polar ionic liquid stationary...
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Comparison of the content of phenolic compounds and antioxidant activity of white, red and black currants (Ribes sp.) extracts
PublikacjaThe aim of this study was to compare the content of antioxidant compounds and the antioxidant activity of extracts from white, red and black currants (Ribes sp.). The chemical properties verified included determinations of anthocyanins and other phenols by HPLC-DAD-MS, total antioxidant activity by standard spectrophotometric tests (ABTS, DPPH and FCR), and profiles of antioxidants by TLC with visualization reagents (ABTS, DPPH,...
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Formation of chlorinated breakdown products during degradation of sunscreen agent, 2-ethylhexyl-4-methoxycinnamate in the presence of sodium hypochlorite
PublikacjaIn this study, a new degradation path of sunscreen active ingredient, 2-ethylhexyl-4-methoxycinnamate (EHMC) and 4-methoxycinnamic acid (MCA) in the presence of sodium hypochlorite (NaOCl), was discussed. The reaction products were detected using gas chromatography–mass spectrometry (GC-MS). Since HOCl treatment leads to more polar products than EHMC, application of polar extracting agents, dichloromethane and ethyl acetate/n-hexane...
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ZnO-decorated green-synthesized multi-doped carbon dots from Chlorella pyrenoidosa for sustainable photocatalytic carbamazepine degradation
PublikacjaThe promising green synthesis of carbon dots (CDs) from microalga Chlorella pyrenoidosa was achieved using simple hydrothermal and microwave-assisted methods. Doping of nanomaterials by nonmetals (N, S, and P) was confirmed by X-ray photoelectron spectroscopy (XPS), while the existence of metals in the CDs was confirmed by inductively coupled plasma optical emission spectroscopy (ICP-OES) and transmission electron microscopy (TEM),...
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Synthesis, characteristics, and photocatalytic activity of zinc oxide nanoparticles stabilized on the stone surface for degradation of metronidazole from aqueous solution
PublikacjaAbstract Background: The presence of antibiotics such as metronidazole in wastewater even at low concentrations requires searching for a suitable process such as advanced oxidation process (AOP) to reduce the level of pollutants to a standard level in water. Methods: In this study, zinc oxide (ZnO) nanoparticles were synthesized by thermal method using zinc sulfate (ZnSO4) as a precursor, then, stabilized on stone and was used...
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Phenolic compounds from Nerium oleander leaves: microwave assisted extraction, characterization, antiproliferative and cytotoxic activities
PublikacjaA microwave-assisted extraction (MAE) method was used for the extraction of phenolic compounds from Nerium oleander leaves. The influence of variables such as ethanol concentration, microwave power, irradiation time and liquid/solid ratio on polyphenol extraction was modelled using a second-order regression equation based on response surface methodology (RSM). The optimal conditions for MAE were: extraction solvent 35% ethanol...
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Monte Carlo simulations of the fracture resistance degradation of asphalt concrete subjected to environmental factors
PublikacjaThe paper presents the results of laboratory tests of SCB (semi-circular beam) samples of asphalt concrete, subjected to the destructive effect of water and frost as well as the aging processes. The determined values of material parameters show significant dispersions, which makes the design of mixtures difficult. Statistical analysis of the test results supplemented by computer simulations made with the use of the proprietary...
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The thermostability, bioactive compounds and antioxidant activity of some vegetables subjected to different durations of boiling: investigation in vitro
PublikacjaThis research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of theirbioactive compounds, antioxidant activity and thermostability.It was found that polyphenols (mg GAE/g), flavanols (mg GAE/g), flavonoids (mg CE/g), anthocyanins (mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots...
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DETERMINATION OF SURFACTANTS IN ENVIRONMENTAL SAMPLES - PART I. CATIONIC COMPOUNDS = Oznaczanie Surfaktantów W Próbkach Środowiskowych. Część I. Związki Kationowe
PublikacjaCompounds from the group of cationic surfactants are widely applied in household, industrial, cleaning, disinfectant, cosmetic and pharmaceutical products as their specific properties (antimicrobial, emulsifying, anticorrosion, softening). After use, cationic surfactants are disposed to wastewater-treatment plants and finally with effluent water to surface waters due to their incomplete degradation. Moreover, they can freely circulate...
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Stability studies of selected polycyclic aromatic hydrocarbons in different organic solvents and identification of their transformation products
PublikacjaGłównym problemem w laboratoriach analitycznych jest konserwacja próbek i ekstraktów przeznaczonych do analizy. Rozpatrując procesy degradacji z analitycznego punktu widzenia i związanej z tym wiarygodności uzyskiwanych wyników pod uwagę należy wziąć wpływ procesów degradacji w badanym elemencie środowiska na poziom stężenia składników śladowych; wpływ tych samych procesów na poziom składników śladowych w już pobranych próbkach...
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Solvatochromic studies of pull–push molecules containing dimethylaniline and aromatic hydrocarbon linked by an acetylene unit
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Geochemical markers and polycyclic aromatic hydrocarbons in solvent extracts from diesel engine particulate matter
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Synthesis, characterization, and application of 2D/2D TiO2-GO-ZnFe2O4 obtained by the fluorine-free lyophilization method for solar light-driven photocatalytic degradation of ibuprofen
PublikacjaIn this study, we report the potential of 2D/2D TiO2- GO-ZnFe2O4 photocatalyst obtained using the fluorine-free lyophilization technique for the degradation of ibuprofen belonging to the group of active pharmaceutical ingredients (API). The improved ibuprofen degradation under simulated solar light was achieved in the presence of a composite of 2D TiO2 combined with GO and embedded ZnFe2O4, which additionally provides superparamagnetic...
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Application of deep eutectic solvents for separation and determination of bioactive compounds in medicinal plants
PublikacjaThe medicinal plants industry, particularly in regard to products rich in biologically active substances for maintaining health, has grown by leaps and bounds in the last decade, with sales of over-the-counter drugs containing these substances growing by billions of dollars. Attention has thus also been paid to the safety and effectiveness of these medicines. We are currently witnessing a rapid increase in the number of publications...
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The termostability, bioactive compounds and antioxidant activity of some vegetables subjected to different durations of boiling: investigation in vitro.
PublikacjaThis research was performed in order to compare the water and acetone extracts of raw and boiled for 10, 20, 40 and 60 min Korean lotus roots (KLR) and Polish white onion (PWO) in the contents of theirbioactive compounds, antioxidant activity and thermostability. It was found that polyphenols (mg GAE/g), flavanols (mg GAE/g), flavonoids (mg CE/g), anthocyanins(mg CGE/kg) and tannins (mg CE/g) in water extract of raw lotus roots...
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Methods of assaying volatile oxygenated organic compounds in effluent samples by gas chromatography—A review
PublikacjaThe paper is a review of the procedures for the determination of volatile and semivolatile oxygenated organic compounds (O-VOCs) in effluent samples by gas chromatography. Current trends and outlook for individual steps of the procedure for the determination of O-VOCs in effluents are discussed. The available sample preparation techniques and their limitations are described along with GC capillary columns used for O-VOCs separation...
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Understanding the early-stage release of volatile organic compounds from rapeseed oil during deep-frying of tubers by targeted and omics-inspired approaches using PTR-MS and gas chromatography
PublikacjaDuring deep-frying, a plethora of volatile products is emitted with the fumes. These compounds could act as oil quality indicators and change the indoor air composition leading to health risks for occupants. The presented experiments focus on deep-frying of different tubers in rapeseed oil at different frying temperatures. Here, two scenarios for real-time monitoring of volatile organic compounds (VOCs) using proton transfer reaction...
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The role of biodegradable particulate and colloidal organic compounds in biological nutrient removal activated sludge systems
PublikacjaThe efficiency of denitrification and enhanced biological phosphorus removal in biological nutrient removal activated sludge systems is strongly dependent on the availability of appropriate carbon sources. Due to high costs of commercial compounds (such as methanol, ethanol, acetic acid, etc.) and acclimation periods (usually) required, the effective use of internal substrates is preferred. The aim of this study was to determine...
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Possibilities of Phoslock® application to remove phosphorus compounds from wastewater treated in hybrid wetlands
PublikacjaTreatment wetland technologies for wastewater treatment can be easily applied for removal of all pollutants except phosphorous. They are applicable in a small towns and rural areas, places where conventional wastewater treatment plant cannot properly operate because of common economic constraints. In Poland only the 8% of rural areas are equipped with sewer system, thus treatment wetlands might be an alternative, effective and...
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Enhanced solar light photocatalytic performance of Fe-ZnO in the presence of H2O2, S2O82−, and HSO5− for degradation of chlorpyrifos from agricultural wastes: Toxicities investigation
PublikacjaThis study reported Fe doped zinc oxide (Fe-ZnO) synthesis to degrade chlorpyrifos (CPY), a highly toxic organophosphate pesticide and important sources of agricultural wastes. Fourier transform infrared, X-ray diffraction, scanning electron microscope, and energy-dispersive X-ray spectroscopic analyses showed successful formation of the Fe-ZnO with highly crystalline and amorphous nature. Water collected from agricultural wastes...
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Investigating COVID-19 active pharmaceutical ingredients (APIs) degradation using Peroxydisulfate/FeMnOx binary metal oxide/Ultrasound System
PublikacjaDegradation of Favipiravir using a hybrid system of peroxydisulfate, FeMnOx binary metal oxide, and ultrasound irradiation was studied. A novel catalyst was synthesized with deep eutectic solvent (DES). The effects of DES type on catalytic performance was evaluated and the catalysts were characterized using XRD, SEM, BET, XPS, and EDS. DES-based catalysts exhibited higher efficiency due to structure change, surface area enhancement...
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Preparation and Characterization of Au/Pd Modified-TiO2 Photocatalysts for Phenol and Toluene Degradation under Visible Light—The Effect of Calcination Temperature
PublikacjaRutile loaded with Au/Pd nanoparticles was prepared using a water-in-oil microemulsion system of water/AOT/cyclohexane followed by calcination.Theeffect of calcination temperature (from350 to 700∘C) on the structure ofAu/Pd nanoparticles deposited at rutile matrix and the photocatalytic properties of Au/Pd-TiO2 was investigated in two model reactions (toluene degradation in gas phase and phenol degradation in aqueous phase). The...
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ASSESSMENT OF VOLATILE ORGANIC COMPOUNDS EMISSIONS FROM RECYCLED LOW-DENSITY POLYETHYLENE STREAMS
PublikacjaThe recycling of plastics is currently one of the most significant industrial challenges. Due to the enormous amounts of plastic wastes generated by various industry branches, it is essential to look for the potential methods of their utilization. Nevertheless, it should not be forgotten that recycled plastics are not pure materials, and they still may show an unfavorable environmental impact. They may contain different contaminants...
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Degradation of Polypropylene Membranes Applied in Membrane Distillation Crystallizer
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Thermal degradation of copolymers based on selected alkyl methacrylates
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Odour Samples Degradation During Detention in Tedlar® Bags
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Hydrogen degradation of structural steels in technical hydrocarbon liquids
PublikacjaDla stali stopowych przeprowadzono badania absorpcji wodoru, mechaniczno-korozyjne przy stałej małej prędkości odkształcania, przy stałym obciążeniu i przy obciążeniu cyklicznie-zmiennym. Środowiskiem było paliwo kotłowe, przepracowany olej mineralny oraz gliceryna. Stwierdzono, iż pochłonięty wodór nie powoduje przedwczesnego zniszczenia stali poddanych działaniu stałego obciążenia ponizej granicy plastyczności oraz, że zaabsorbowany...
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Environmental degradation of the Cr-Mo steels in liquid hydrocarbons
PublikacjaPrzedstawiono podatność stali stopwych 26H2MF i 34HNM do naprężeniowego pękania korozyjnego. Środowiskiem do badań było paliwo ciężkie i zużyty olej mineralny.
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Photosensitive chitosan for visible-light water pollutant degradation
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An experimental investigation of the influence of plasticity on creep degradation rate
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Hydrogen degradation of high strength low alloyed steels.
PublikacjaBadano wpływ polaryzacji katodowej na własności stali węglowej, stali o podwyższonej i wysokiej wytrzymałości metodą stałego powolnego odkształcania.Stwierdzono, że stopień kruchości wodorowej każdej z badanych stali zależał od stężenia wodoru dyfuzyjnego.
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Photocatalytic degradation using nitrogen-modified titanium dioxide
PublikacjaPrzepływowy reaktor z wypełnieniem został zastosowany do przeprowadzenia fotodegradacji 4-chlorofenolu za pomocą światła widzialnego. Fotokatalizator w postaci tlenku tytanu(IV) modyfikowanego azotem, został naniesiony na powierzchnię kulek szklanych. Źródło światła widzialnego stanowiła 8W lampa fluorescencyjna. Powietrze było w sposób ciągły przepuszczane przez zawartość reaktora.
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Pathways and analytical tools in degradation studies of organic pollutants
PublikacjaWszystkie substancje chemiczne podlegają różnym procesom w wyniku wielu reakcji chemicznych, biochemicznych czy też fotochemicznych. W zależności od elementu środowiska w jakim znajduje się analit (np.: gleba, sedymenty, wody powierzchniowe i podziemne), może on ulegać powolnym przemianom w wyniku różnych procesów. W pracy przedstawiono niektóre drogi degradacji wybranych substancji w różnych warunkach. Omówiono problem identyfikacji...
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An experimental investigation of the influence of plasticity on creep degradation rate
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Hydrogen degradation of high-strength weldable steels in seawater
PublikacjaOceniono podatność na niszczenie wodorowe stali spawalnych o wysokiej wytrzymałości przy obciążeniach monotonicznie rosnących. Badano dwa gatunki stali ulepszonych cieplnie i ich złącza spawane. Przeprowadzono próby rozciągania z małą prędkością odkształcania w wodzie morskiej przy polaryzacji katodowej. Wykonano próby przenikania wodoru metodą Devanathana-Stachurskiego.
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Degradation of ferritic X10CrAlSi18 stainless steel caused by slurry
PublikacjaThe slurry erosion tests of ferritic X10CrAlSi18 steel were carried out using a slurry pot device. In order to investigate the erosion process, two series of tests were performed: first one with a constant impact velocity of 5 m/s, 7 m/s and 9 m/s and the second one, during which the impact velocity was changed after every exposure. During each test, an influence of test conditions on volume loss, surface hardness and roughness...
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Environmental Degradation of Engineering Materials & Materials Engineering and Technologies
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The influence of the UV irradiation on degradation of virgin rapeseed oils
PublikacjaThis paper presents research which is a continuation of the investigations described earlier. The aim of these studies was to determine the influence of UV irradiation on flavor and the oxidative stability of different rapeseed oils varieties. For the purpose of this study, oil samples underwent accelerated deterioration for 4.5 h under a UV light test. In the obtained sample, characteristic values (peroxide (PV, 1.23–1.62 meq...
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Terahertz investigations on some bi-heterocyclic compounds
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Pervaporation of volatile organohalogen compounds throughpolydimethylsiloxane membrane
PublikacjaThe objective of this work was to apply dense polymeric membranes for pervaporation of tetrachloroethene from aqueous solution. Three membranes were evaluated: polydimethylsiloxane (PDMS-PV1 and PDMSPV2) membranes, and a PDMS with ZSM-5 zeolite filled (PERVAP-1070) membrane. The effect of feed composition on flux and selectivity was also investigated. Tested membranes showed good properties in the separation of tetrachloroethylene,...
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Baltic cyanobacteria – a source of biologically active compounds
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Photochemical decomposition of endocrine disrupting compounds – A review
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Inhibition of cancer antioxidant defense by natural compounds
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Persulfate activation by organic compounds: advancements and challenges
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