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Search results for: aroma compounds
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Green sample preparation techniques for chromatographic determination of small organic compounds
PublicationAccurate monitoring of the state of the environment requires the introduction of additional isolation and/or preconcentration step prior to the chromatographic determination. In this work the information about novel methodological and instrumental solutions in relation to different variants of microextraction techniques are presented. Attention is focused on analytical procedure and suitable analytical tools for extraction of the...
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Phytoecdysteroid containing plants – a source of bioactive compounds with potential anticarcinogenic effects
PublicationEcdysteroids are a group of steroids synthesized in inver- tebrates as molting hormones and also in some plants as secondary metabolites acting as a defense against parasites. These compounds do not naturally occur in mammals and are not structurally related to mammalian steroid hor- mones, consequently do not activate mammalian hormone receptors. Ecdysteroids exhibit very low toxicity to mam- mals and to date no serious side effects...
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Quality problems in the determination of organic compounds in environmental samples, such as PAHs and PCBs
PublicationPrzedstawiono i skomentowano wyniki badań międzylaboratoryjnych w zakresie oznaczania wybranych związków organicznych w próbkach środowiskowych. Oznaczenia wykonane były przez niezależne laboratoria analityczne, które stosowały różne procedury przygotowania próbek do analizy.Badania wskazują, że wynik oznaczania poszczególnych analitów zależny był od stosowanej przez laboratorium procedury izolacji i oznaczania. Stwierdzono różnice...
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Formation of intermetallic compounds in the solid-liquid composites of the Ga-Ni system
PublicationThe processes of formation of intermetallic compounds in the composite system of liquid gallium-nickel powder by the methods of x-ray diffraction, scanning electron microscopy and differential thermal analysis have been studied. A change in the phase composition was discovered and the influence of thermal treatment of the composites under investigation on the phase formation processes was analyzed. The mechanism of gallium enriched...
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Nutritional and Pharmaceutical Properties of Bioactive Compounds in Organic and Conventional Growing Kiwifruit
PublicationThe bioactivity of two kiwifruit’s cultivars growing under organic and conventional conditions were studied and compared. The bioactive compounds were extracted with water and ethanol using similar conditions which are applied in pharmaceutical applications and for daily fruit consumption such as tea drink. Antioxidant radical scavenging assays [ferric-reducing/antioxidant power (FRAP); cupric reducing antioxidant capacity (CUPRAC);...
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The speciation of organotin compounds in sediment and water samples from the port of Gdynia
PublicationOrganotin compounds (OTC) are toxic towards all living organisms. The application of organitin-based antifouling systems is becoming the main source of OTC in the ocean. Harbor sediments and water contain large deposits of organotin compounds due to application of antifouling systems in the shipping industry. OTC contamination presents a potential risk to the marine environment. Sediment and water samples were collected in 2009...
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Structural and electronic properties of some intriguing (rare-earth)Ba2Cu3O7 compounds.
PublicationW rozdziale przedstawiono przegląd wyników eksperymentalnych i teoretycznych dotyczących wybranych związków o wzorze (lantanowiec)Ba2Cu3O7 wykazujących całkowicie odmienne właściwości w porównaniu z całą klasą nadprzewodzących związków tlenkowych o stechiometrii 1:2:3. Szczególny nacisk położono na analizę procesu wzrostu kryształów i powstawania defektów punktowych determinujących późniejsze własności fizyczne tych materiałów....
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Degradacja związków organicznych w środowisku. Degradation of organic compounds in the environment
PublicationZwiązki organiczne w zależności od elementu środowiska, w jakim występują (gleba, osady denne, wody powierzchniowe i gruntowe), mogą ulegać - pod wpływem rozmaitych procesów chemicznych, fizycznych, biologicznych czy też foto-chemicznych - różnorakim przemianom. Przedstawiono drogi degradacji wybranych trwałych zanieczyszczeń organicznych w różnych warunkach. Omówiono problem pojawiania się produktów pośrednich w czasie degradacji...
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Non-regulated organic compounds (NROC's) in the Odra River water samples.
PublicationW ramach badań opisanych w pracy podjęto próbę identyfikacji lotnych i średniolotnych związków z grupy Non-Regulated Organic Compounds obecnych w próbkach wody rzecznej. Analizie poddano 25 próbek wód pobranych z rzeki Odry w październiku 2000, w trakcie VIII kampanii zorganizowanej w ramach International Odra Project (IOP). W badaniach wykorzystano technikę PT-TD-GC-MS.Komputerowa analiza widm masowych wykazała obecność wielu...
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Impact of high-pressure processing on the bioactive compounds of milk - A comprehensive review
PublicationHigh-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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Coacervative extraction as a green technique for sample preparation for the analysis of organic compounds
PublicationOne of the present trends in analytical chemistry is miniaturization, which is one of the methods of green analytical chemistry application. A particular emphasis is placed on the elimination of the use of large amounts of organic solvents which are toxic and harmful to the environment, maintaining high efficiency of the extraction process, high recovery values and low values of quantification (LOQ) and detection (LOD) limits....
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The II phase metabolism of endogenous and exogenous compounds, including antitumor chemotherapeutics
PublicationThe II phase metabolism, it is a set of metabolism and excretion pathways of endogenous as well as exogenous compounds including xenobiotics. UDP-glucuronyltransferases (UGTs; EC 2.4.1.17) are the most crucial representatives of II phase enzymes, which are responsible for the transformation of bilirubine and bile acids, steroids and thyroid hormones and lipids. Exogenous compounds, including drugs, carcinogens, environmental pollutants...
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Application of electrochemical sensors and sensor matrixes for measurement of odorous chemical compounds
PublicationIn this paper describes the principle of operation of the electrochemical sensors and the sensor matrixes comprised of electrochemical sensors intended for measurement of odorous compounds. Critical comparison of these sensors’ advantages and disadvantages has been made. The fields of economy contributing to release of odours and the potential sources of their emission have been identified. Commercially available electrochemical...
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In-tube extraction for the determination of the main volatile compounds in Physalis peruviana L
PublicationAn analytical procedure based on in-tube extraction followed by gas chromatography with mass spectrometry has been developed for the analysis of 24 main volatile components in cape gooseberry (Physalis peruviana L.) samples. According to their chemical structure, the compounds were organized into different groups: one hydrocarbon, one aldehyde, four alcohols, four esters, and 14 monoterpenes. By single-factor experiments, incubation...
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Determination of Surfactants in Environmental Samples. Part III. Non-Ionic Compounds
PublicationNon-ionic surface active agents are a diverse group of chemicals which have an uncharged polar head and a non-polar tail. They have different properties due to amphiphilic structure of their molecules. Commercial available non-ionic surfactants consist of the broadest spectrum of compounds in comparison with other types of such agents. Typically, non-ionic compounds found applications in households and industry during formulation...
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Cross section calculations for electron scattering from platinum chemotherapeutic compounds
PublicationCross section for electron impact ionization of carboplatin, C6H12N2O4Pt, and oxaliplatin, C8H14N2O4Pt, have been calculated within binary-encounter-Bethe model for energies from the ionization threshold up to 5000 eV. Cross section for elastic electron scattering from carboplatin and oxaliplatin molecules have also been derived using independent atom method (IAM) and additivity rule for collision energies ranging from 50 eV to...
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Removal of BTEX Compounds From Waste Gases; Destruction and Recovery Techniques
PublicationThe tendency for BTEX compounds (benzene, toluene, ethylbenzene, xylenes) to spread into all compartments of the environment together with their influence on both ecosystem and human health means that the emission of thesecompounds into the air is becoming the matter of worldwide concern. The legal regulations introduced by the European Union governing the assessment and management of air quality obliges member states to systematically...
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Bullettino della Commissione archeologica comunale di Roma
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Improvement of charge separation in TiO 2 by its modification with different tungsten compounds
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A review of the biogeochemical controls on the occurrence and distribution of polycyclic aromatic compounds (PACs) in coals
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Adsorption from aqueous solutions of chlorinated organic compounds onto activated carbons
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Hydrazone Linker as a Useful Tool for Preparing Chimeric Peptide/Nonpeptide Bifunctional Compounds
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Biological Activity of Compounds Exhibiting Local Anesthetics's Properties Evaluated by QSAR Approach
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QSAR Analysis of Selected Antimicrobial Structures Belonging to Nitro-derivatives of Heterocyclic Compounds
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Advanced oxidation processes for recalcitrant compounds removal comparison with biofiltration by Corbicula fluminea
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Edible Flowers Extracts as a Source of Bioactive Compounds with Antioxidant Properties—In Vitro Studies
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Microextraction Techniques Used in the Procedures for Determining Organomercury and Organotin Compounds in Environmental Samples
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Organomercury Compounds in Environmental Samples: Emission Sources, Toxicity, Environmental Fate, and Determination
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Removal of organic compounds from water by solvent sublation. Criteria for solvent selection.
PublicationProces flotoekstrakcji zastosowano do usuwania z wody następujących związków organicznych: tetrachlorku węgla, chloroformu, 1,3,5-trimetylobenzenu (mezytylenu), fenolu i 2,4,5-trichlorofenolu. Jako odbierające fazy organiczne użyto: olej mineralny, 1-dekanol, 1-oktanol, octan amylu, dodekan i tetradekan. Mechanizmem decydującym o usuwaniu lotnych związków organicznych (VOC) było odparowanie do wnętrza pęcherzyków gazu, podczas...
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Nitrobenzimidazoles as Substrates for DT-Diaphorase and Redox Cycling Compounds: Their Enzymatic Reactions and Cytotoxicity
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Bioactive Compounds of Blueberries: Post-Harvest Factors Influencing the Nutritional Value of Products
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Chirality sensing of bioactive compounds with amino alcohol unit via circular dichroism
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Interfacial behavior of polar, weakly polar, and nonpolar compounds bound to activated carbons
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Cold-modulated leaf compounds in winter triticale DH lines tolerant to freezing and
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Intermetallic disordered magnet Gd2Pt1.1Ge2.9 and its relation to other AlB2 -type compounds
PublicationThe 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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Application of deep eutectic solvents for separation and determination of bioactive compounds in medicinal plants
PublicationThe 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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PRELIMINARY RESULTS FROM APPLICATION PHOSLOCK® TO REMOVE PHOSPHORUS COMPOUNDS FROM WASTEWATER
PublicationThe aim of the study is to assess the removal effectiveness of phosphorus compoundsby using lanthanum-modified bentonite. This material was produced by the Australian company Phoslock® Water Solutions Pty Ltd. According to the company, Phoslock® has substantial capacity to bound phosphate anions. The investigation was carried out in steady conditions in laboratory model with beakers. The results of the study are related to the...
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Problems and challenges associated with estimating the emissions of organic compounds from indoor materials
PublicationFor several years intensive research has been carried out with the aim of developing a database of the types and amounts of pollutants released from indoor materials to the indoor environment. The paper discusses in detail basic problems and challenges encountered when estimating the emissions of chemical compounds released from of indoor materials. Factors affecting the validity of data obtained by using two different types of...
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Nitrogen and phosphorus compounds in coastal aquifers in Puck municipality area (northern Poland)
Publication1. Groundwater study shows local variations in chemical composition of selected aquifers caused by human impact The diversity is mainly manifested in • time variation of groundwater chemical composition of all analyzed parameters especially in shallow aquifers (Q1) • relationship between t he ground water chemical composition and depth of the aquifer where an inverse concentration distribution occurs higher concentrations are observed...
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Role of Herbal Bioactive Compounds as a Potential Bioavailability Enhancer for Active Pharmaceutical Ingredients
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Characteristics of volatile organic compounds emission profiles from hot road bitumens
PublicationA procedure for the investigation and comparison of volatile organic compounds (VOCs) emission profiles to the atmosphere from road bitumens with various degrees of oxidation is proposed. The procedure makes use of headspace analysis and gas chromatography with universal as well as selective detection, including gas chromatography–mass spectrometry (GC–MS). The studies revealed that so-called vacuum residue, which is the main component...
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Miniaturized passive emission test chamber for in-situ measurement of emissions of organic compounds
PublicationThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air (outdoor). One of the main groups of chemical compounds present in indoor air, with proven harmfulness to health,are volatile organic compounds (VOCs). VOCs present indoor comprise a wide variety of hydrocarbons and hydrocarbons derivatives including aliphatic, aromatics, alkylbenzens,...
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Application of BDD thin film electrode for electrochemical decomposition of heterogeneous aromatic compounds
PublicationThe aim of the presented study is to investigate the applicability of electrochemical oxidation of aromatic compounds containing heteroatoms, e.g. waste from production of pesticides or pharmaceutics, at a borondoped diamond (BDD) electrode. The BDD electrodes were synthesized by microwave plasma enhanced chemical vapour deposition (MW PE CVD). Investigation of the electrode surface by optical microscopy and scanning electron microscopy...
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SURFACTANTS IN KLODNICA RIVER (KATOWICE, POLAND). PART II. QUATERNARY AMMONIUM COMPOUNDS
PublicationThe paper presents methods of determination of analytes of the cation group (alkyl benzyl dimethyl ammonium (BDDA-C12-C16), alkyl trimethyl ammonium (TMA), hexadecyl piridinium (HP)) in surface water and bottom sediment samples. In the sample preparation phase the solid phase extraction (SPE) or accelerated solvent extraction/ultrasound assisted extraction (ASE/UAE)-SPE technique was used and in the identification phase and quantitative...
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Comparison of the contents of bioactive compounds and the level of antioxidant activity in different kiwifruit cultivars
PublicationGłównym celem prowadzonych badań było stwierdzenie która z odmian owoców kiwi (''Hayward'', ''Daeheuhg'', ''Haenam'' oraz ''Bidan'') jest najbardziej odpowiednią z punktu widzenia konsumpcji przez człowieka. Z tego powodu w odpowiednio przygotowanych próbkach ekstraktów z owoców kiwi oznaczono:- profile związków bioaktywnych;- poziomy aktywności przeciwutleniającej. Wyniki pomiarów zawartości polifenoli (flawonoidy oraz kwasy fenolowe)...
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Influence of composition of raw wastewater on removal of nitrogen compounds in multistage treatment wetlands
PublicationInfluence of composition of raw wastewater on the efficiency of organic matter and nitrogen removal in multistage treatment wetlands has been examined. Commonly used indicators, like COD/BOD5 and BOD5/TN ratio, determining wastewater susceptibility to biodegradation in conventional treatment technologies were assessed. It was confirmed that multistage treatment wetland may be used for treatment of wastewater with high loads of...
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Miniaturized Passive Emission Chambers for In Situ Measurement of Emissions of Volatile Organic Compounds
PublicationThe results of many different studies have demonstrated unequivocally that the quality of indoor air is often much worse than that of atmospheric air. The presence of dangerous chemical compounds in indoor air can have an adverse impact on human health and cause numerous diseases of the respiratory and circulatory systems. Such harmful chemicals get into indoor air as a result of their emission from building and indoor materials....
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Chemically modified glass fiber as a matrix-free reference material for volatile compounds
PublicationW pracy opisano sposób wytwarzania nowego typu bezmatrycowych materiałów odniesienia lotnych związków organicznych. Do otrzymywania lotnych analitów wykorzystano technikę termicznego rozkładu związków powierzchniowych. Jako nośnik zastosowano modyfikowane chemicznie włókna szklane. Związkiem oznaczanym był chlorek metylu.
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Organotin compounds in the liver tissue of marine mammals from the PolishCoast of the Baltic Sea.
PublicationOznaczono zawartość związków cynoorganicznych w próbkach wątrób pochodzących od ssaków morskich złowionych w polskiej strefie ekonomicznej Morza Bałtyckiego. W ramach przeprowadzonych badań opracowana została oryginalna metodyka analityczna. Całkowite stężenie związków z tej grupy wahało się w granicach od 43,9 do 7698 ng Sn/g próbki (w przeliczeniu na suchą masę). Badano zależność stężeń tych związków od wieku i płci osobników.
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The effect of chlorinated drinking water consumption on levels of volatile organohalogen compounds in urine.
PublicationW przedstawionej pracy podjęto próbę oznaczenia niezmienionych form lotnych rozpuszczalników chlorowcoorganicznych w próbkach materiału biologicznego jakim jest mocz dawców, używających w gospodarstwie domowym a także w pracy wody uzdatnianej między innymi w procesie chlorowania. Do wykonania oznaczeń zastosowano zmodyfikowaną technikę analizy fazy nadpowierzchniowej nad cienką warstwą cieczy z samoczynną generacją ciekłego sorbentu...