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Search results for: VOLATILE SULFUR COMPOUNDS
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Sulfur compounds: Gas chromatography
PublicationSulfur compounds, due to their properties, are responsible for the damage of our environment. For this reason sulfur containing compounds are of constant concern in many fields. Gas chromatography (GC), due to combination of separation capability and sensitive detection is a prime technique for the analysis of thes compounds in various matrices. The chapter rewies general problems of the determination of these compounds by GC and...
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Pervaporation of volatile organohalogen compounds throughpolydimethylsiloxane membrane
PublicationThe 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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Testing and sampling devices for monitoring volatile and semi-volatile organic compounds in indoor air
PublicationAdults spend most of their time in enclosed spaces (e.g., apartment, office and public buildings). According to research conducted by scientists, air quality indoors is much worse than the ambient air quality outdoors. Hazardous chemicals found in air indoors can adversely affect the functioning of the human body and cause many respiratory and circulatory diseases. Harmful chemical compounds (mainly volatile organic compounds and...
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An attempt to identify volatile and semi-volatile organic compounds present in the Odra river waters.
PublicationCelem pracy była identyfikacja związków z grup lotnych i średniolotnych związkó organicznych. W badaniach wykorzystano technikę Pt-TD-GC-MS. Komputerowa analiza widm masowych wykazała obecność wielu związków organicznych pochodxenia naturalnego i antropogenicznego. W powłokach wód pobranych w okolicy Brzegu Dolnego oznaczono stężenia związków chloroorganicznych na poziomie pojedynczych prób. Nieco wyższe spektrum związków chloroorganicznych,...
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Screening of volatile organic compounds as a source for indoor pollution
PublicationLotne związki organiczne (VOC) stanowią jedne z istotniejszychzanieczyszczeń powietrza wewnętrznego, ich stężenia w powietrzu wewnętrznym są często kilkakrotnie wyższe niż odpowiadające im stężenia w powietrzu zewnętrznym. Ten niekorzystny stosunek stężeń wskazuje na obecność endogennych źródeł emisji (usytuowanych bezpośrednio wewnątrz budynków). Lotne związki organiczne uwalniane są do powietrza wewnętrznego z wielu kontrolowanych...
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Electrochemical sensor for measurement of volatile organic compounds in air
PublicationPrzedstawiono rezultaty badań prototypowego czujnika do oznaczania mrówczanu etylu i formaldehydu w powietrzu. Określono czułość wskazań czujnika i jego granice oznaczalności wykorzystując jako techniki detekcyjne pulsową woltamperometrię różnicową (DPV) oraz woltamperometrię fali prostokątnej (SWV). Elektrodę roboczą i przeciwelektrodę stanowiły elektrody z Pt. Elektrolitem wewnętrznym była ciecz jonowa (chlorek 1-heksylo,3-metyloimidazolinowy)....
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Effect of the ionic liquids on extraction of aromatic and sulfur compounds from the model petrochemical stream
PublicationSuitability of a imidazolium ionic liquids (ILs) as solvents in dearomatization and desulfurization in the ternary systems and in a model multicomponent systems has been analyzed. With this aim, ternary liquid-liquid phase equilibrium data (LLE) have been obtained for ternary mixtures of {IL + benzene, or toluene, or thiophene, or 2-butanethiol + hexane}, or {IL + benzene + 2-methylpentane} at T = 298.15 K and ambient pressure,...
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Distribution of volatile organohalogen compounds in petrochemical plant water streams
PublicationThe study assesses halogenated volatile organic compound concentrations in the water and wastewaterstreams of a petrochemical plant. Water samples were collected at 11 sampling points during 5 samplingcampaigns. The samples were collected from the oil dewaxing unit and in the wastewater treatmentplant. Dichloromethane and 1,2-dichloroethane were the most frequently determined compounds. Tetrachloroethenewas also detected at the...
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Prototype of electrochemical sensor for measurements of volatile organic compounds in gases
PublicationThe paper presents a laboratory prototype of an electrochemical sensor for measurements of volatile organic compounds (VOCs) in gases, utilizing ionic liquids and commercial screen printed electrodes by DropSens. The following ionic liquids have been tested as the electrolyte and redox reaction environment: 1-butyl, 3-methylimidazolium dicyanoamide ([BMIM][N(CN)2]), 1-octyl, 3-methylimidazolium tetrafluoroborate ([OMIM][BF4]),...
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The use of fungi in biofiltration to remove hydrophobic volatile organic compounds
PublicationThe growing importance placed on air quality by environmental regulations and public opinion necessitate the minimization and removal of volatile organic compound emissions (VOCs), including odours. The removal of hydrophobic VOCs from the air by biological methods remains a major technical challenge (despite its importance in the shift to green engineering). A potential solution to this challenge is the use of fungi in biofiltration....
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Separation of volatile compounds from fermentation broth by membrane distillation
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Volatile organohalogen compounds in human urine: the effect of environmental exposure
PublicationW pracy przedstawiono wyniki oznaczania lotnych związków chlorowcoorganicznych w próbkach moczu pochodzących m.in. od dawcow narazonych na kancerogeny w miejscu pracy i dawcow spozywajacych wode poddana procesowi uzdatniania przez chlorowanie. Do izolacji i wzbogacania analitów z moczu, posiadającego skomplikowaną matrycę, wykorzystano technikę analizy fazy nadpowierzchniowej nad cienką warstwą cieczy z samoczynną generacją ciekłego...
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Identification of volatile compounds based on the electrocatalytic gas sensor responses
PublicationMeasured response in case of electrocatalytic gas sensors is in form of a voltamperometric characteristic. Current-voltage (I-V) response shape depends on the gas type and its concentration. Such response contains significantly more information comparing with typical electrochemical sensors, but is quite difficult to analyze. When I-V curve contains current peaks, position of such peaks can be used...
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Identification of volatile compounds in raw spirits of different organoleptic quality
PublicationGłównym celem prezentowanych badań było określenie składu lotnej frakcji destylatów rolniczych, a następnie wyodrębnienie profili zapachowych destylatów rolniczych różniących się właściwościami sensorycznymi ocenionymi na podstawie klasycznej analizy sensorycznej. Profile zapachowe tworzono z wykorzystaniem kapilarnej chromatografii gazowej połączonej ze spektrometrią mas (GC-MS). Do ekstrakcji lotnych związków zastosowano technikę...
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New Method for the Synthesis of Azocrown Compounds Containing Oxygen, Nitrogen and Oxygen, or Sulfur Atoms in the Macroring.
PublicationW publikacji opisano nową metodę syntezy azokoron z różnymi heteroatomami w makrocyklu i o różnej wielkości molekularnej wnęki. Metoda ta polega na reakcji 2,2´-difluoroazobenzenu z diolami, diaminami, aminodiolami i ditiolamiw obecności zasady.
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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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The Novel Quantitative Assay for Measuring the Antibiofilm Activity of Volatile Compounds (AntiBioVol)
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Analysis of volatile organic compounds (VOCs) in water samples. Methods and instrumentation
PublicationW pracy przedstawiono stan wiedzy nt. metodyk analitycznych oraz urządzeń kontrolno-pomiarowych, wykorzystywanych w badaniach próbek wody na zawartość lotnych związków organicznych. Szczególną uwagę zwrócono na techniki izolacji i wzbogacania analitów przed etapem oznaczeń końcowych.
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Microanalysis of volatile organic compounds (VOCs) in water samples - methods and instruments
PublicationW pracy przedstawiono stan wiedzy nt. metodyk analitycznych oraz urządzeń kontrolno-pomiarowych, wykorzystywanych w badaniach próbek wody na zawartość lotnych związków organicznych. Szczególną uwagę zwrócono na techniki izolacji i wzbogacania analitów przed etapem oznaczeń końcowych.
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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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New matrix-free reference materials of volatile compounds - application of glass fibres as support materials for surface compounds
PublicationTechnika 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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New procedure for the control of the treatment of industrial effluents to remove volatile organosulfur compounds
PublicationWe present a new procedure for the determination of volatile organosulfur compounds in samples of industrial effluents using dispersive liquid–liquid microextraction and gas chromatography with flame photometric detection. Initially, the extraction parameters were optimized. These included: type and volume of extraction solvent, volume of disperser solvent, salting out effect, pH, time and speed of centrifugation as well as extraction...
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Exposure to cooking emitted volatile organic compounds with recirculating and extracting ventilation solutions
PublicationEnergy-efficient urban development leads to the compact design of apartments. Recirculating ventilation solutions are an attempt to minimize the space required for ventilation ducting, but more data on their performance are needed. Cooking is a major source of volatile organic compounds (VOCs) emissions. It is necessary to assess how well recirculating kitchen hoods perform in reducing the residents' exposure to cooking fumes compared...
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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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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...
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New procedure for the examination of the degradation of volatile organonitrogen compounds during the treatment of industrial effluents
PublicationWe present a new procedure for the determination of 32 volatile organonitrogen compounds in samples of industrial effluents with a complex matrix. The procedure, based on dispersive liquid–liquid microex-traction followed by gas chromatography with nitrogen-phosphorus and mass spectrometric detection, wasoptimized and validated. Optimization of the extraction included the type of extraction and disperser sol-vent, disperser solvent...
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Ab initio and density functional theory calculations of proton affinities for volatile organic compounds
PublicationThe Hatree-Fock method with 6-311G** split-valence molecular orbitals basis sets and the density function theory-B3LYP have been applied to geometrical optimizations and calculations of total electronic, zero point vibrational energies and proton affinities at 298 K for volatile organic compounds. Calculated values of proton affinities are compared with experimental data.
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Methods of assaying volatile oxygenated organic compounds in effluent samples by gas chromatography—A review
PublicationThe 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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ASSESSMENT OF VOLATILE ORGANIC COMPOUNDS EMISSIONS FROM RECYCLED LOW-DENSITY POLYETHYLENE STREAMS
PublicationThe 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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Determination of volatile organic compounds using solventless sample preparation techniques and gas chromatography
PublicationIn this paper the latest advances in the determination of volatile organic compounds using solvent-free extraction techniques in the sample preparation step are presented. A paper is focus mainly on one of the most popular sample preparation technique: solid-phase microextraction technique (SPME) combined with different detection systems and its applications to sampling of VOCs from the samples with different matrices. This paper...
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The use of various species of fungi in biofiltration of air contaminated with odorous volatile organic compounds
PublicationAir pollution with odorous compounds is a significant social and environmental problem. This paper presents biological deodorization methods. The attention is focused on the application of biotrickling filters for air deodorization. Principles of their operation are discussed, indicating the key role of the selection of microorganisms responsible for the degradation of odorous compounds. A literature overview of the used fungal...
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Highly effective asphaltene-derived adsorbents for gas phase removal of volatile organic compounds
PublicationA novel nitrated asphaltene-derived adsorbent (Asf-Nitro) was prepared using facile isolation and modification procedures. The successful modification was confirmed by Fourier-transform infrared spectroscopy (FTIR). The nitrated adsorbent was evaluated in terms of dispersive and specific interactions, Lewis acid-base properties and adsorption isotherms by means of inverse gas chromatography (IGC). Nitration was found to be extremely...
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The effect of fixed adsorption bed height on adsorption of gaseous mixture of volatile organic compounds
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Determination of volatile organohalogen compounds in urban precipitation in Tricity area (Gdańsk, Gdynia, Sopot).
PublicationPróbki opadów atmosferycznych pobierano w 4 punktach na terenie Gdańska i Sopotu, od listopada 2000 do maja 2001. Oznaczano chloro- i bromopochodne metanu, etanu i etenu. Lotne związki chlorowcoorganiczne oznaczane były metodą bezpośredniego nastrzyku próbki wody do kolumny kapilarnej z wykorzystaniem detektora wychwytu elektronów na etapie detekcji (DAI-GC-ECD). Najczęściej oznaczanymi związkami na wszystkich stacjach pobierania...
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Application of cyanated asphaltenes in gas-phase adsorption processes for removal of volatile organic compounds
PublicationThe paper presents an innovative, chemically modified (methylcyanated) asphaltene-based adsorbent that can be an inter-esting low-cost alternative for traditional adsorbents. Adsorption properties of adsorbents were examined by inverse gas chromatography technique, adsorption isotherms, and breakthrough curves. A significant increase in retention volume for pyridine, 2-pentanone, nitropropane, toluene, and 1-butanol was observed....
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Electrochemical sensor for measurement of volatile organic compounds employing square wave perturbation voltage
PublicationThe paper presents the results of investigation on a prototype sensor for measurement of benzaldehyde in air. Sensitivity and limit of quantification of the sensor were determined for different internal electrolyte using the square wave voltammetry (SWV) as a detection technique. The working and counter electrodes were made of platinum. Ionic liquids 1-hexyl, 3-methylimidazolium chloride,1-hexyl, 3-methylimidazolium bis (trifluoromethanesulfonyl)...
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Investigation of volatile low molecular weight compounds formed during continuous reclaiming of ground tire rubber
PublicationGround tire rubber was thermo-mechanically reclaimed at different temperature conditions (80, 120, 160 °C) using a co-rotating twin screw extruder. The progress of ground tire rubber reclaiming was evaluated with specific mechanical energy, sol fraction and thermogravimetric analysis. Volatile organic compounds (VOCs) including volatile sulfur compounds (VCSs) released from ground tire rubber and ground tire rubber after reclaiming...
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part II. Sample collection and preparation
PublicationThe paper reviews literature information on air sampling techniques commonly used for monitoring volatile organic compounds (VOCs) levels in atmospheric air. It describes containers for collecting samples of atmospheric air, such as vacuum canisters and bags made from synthetic materials. It discusses dynamic, passive and denudational techniques for sampling analytes from air combining isolation with preliminary enrichment, and...
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IDENTIFICATION OF ODOR OF VOLATILE ORGANIC COMPOUNDS USING CLASSICAL SENSORY ANALYSIS AND ELECTRONIC NOSE TECHNIQUE
PublicationThe paper compares two methods of analysis of odour of volatile organic compounds: classical sensory analysis and electronic nose technique. Eight volunteers participated in the classical sensory analysis investigations, which lasted two weeks. An instrumental odour analysis involved a prototype of 6-sensor electronic nose designed by the authors. The research performed with this device provided higher reproducibility and reliability...
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Removal of Volatile Organic Compounds (VOCs) from Air: Focus on Biotrickling Filtration and Process Modeling
PublicationBiotrickling filtration is a well-established technology for the treatment of air polluted with odorous and volatile organic compounds (VOCs). Besides dozens of successful industrial applications of this technology, there are still gaps in a full understanding and description of the mechanisms of biotrickling filtration. This review focuses on recent research results on biotrickling filtration of air polluted with single and multiple...
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Investigations on the removal of hydrophobic odorous volatile organic compounds by biotrickling filtration monitored with electronic nose
PublicationThe presented paper presents the results of research on the removal of selected hydrophobic volatile organic compounds (VOCs) from their mixture with air by means of a trickled-bed biofiltration. The efficiency of the removal of toluene and α-pinene, as model VOCs, in a three-section biotrickling filter is evaluated using GCFID and additionally monitored with an electronic nose. The results show that the removal of the model mixture...
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Monitoring of volatile organic compounds (VOCs) in atmospheric air. Part I. On-line gas analyzers
PublicationThe paper reviews the subject literature concerning the analytical instruments routinely used for monitoring volatile organic compounds in atmospheric air. The analyzers are classified as stationary or mobile according to their ease of transport. Stationary DOAS (Differential Optical Absorption Spectroscopy) analyzer is characterized, as are MIMS (Membrane Introduction Mass Spectrometry), MESI (Membrane Extraction with Sorbent...
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Real-time monitoring of the emission of volatile organic compounds from polylactide 3D printing filaments
PublicationEstablishing the emission profile of volatile organic compounds generated during fused deposition modeling 3D printing using polymer filaments is important in terms of both understanding the processes taking place during thermal degradation of thermoplastics, and assessing the user's exposure to potentially harmful volatiles. However, obtaining detailed, real-time qualitative and quantitative results poses a challenge. In this...
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Volatile organic compounds in gastrointestinal stromal tumour tissue originating from patient-derived xenografts
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Sample preparation for gas chromatographic determination of halogenated volatile organic compounds in environmental and biological samples
PublicationPodstawowym elementem przygotowania próbek środowiskowych i biologicznych do analizy jest etap izolacji i/lub wzbogacania polegający na przeniesieniu analitów z matrycy pierwotnej charakteryzującej się złożonym i często zmiennym składem (próbka oryginalna) do matrycy wtórnej z równoczesnym usunięciem substancji przeszkadzających (izolacja)i zwiększeniem stężenia analitów do poziomu powyżej granicy oznaczalności stosowanego przyrządu...
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Determination of Volatile Organic Compounds in Indoor Air in the Gdansk Area Using Permeation Passive Samplers
PublicationPassive dosimetry — known for over a hundred years — is still a useful tool in monitoring air pollutants. In this work, permeation passive samplers were used to determine indoor air quality in 22 apartments located in the Gdansk area in the northern part of Poland. The results obtained by the passive sampling technique were compared to those obtained by dynamic sampling. Attempts were also made to identify indoor sources of...
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Metal-coated fused silica fibres as a support for immobilized compounds yielding a volatile analyte (C2H4)
PublicationPrzedstawiono wyniki badań dotyczących wykorzystania chemicznie modyfikowanych włókien szklanych pokrytych warstwą metalu (aluminium), jako nośników związków powierzchniowych. W trakcie procesu termicznego rozkładu z tak zmodyfikowanych włókien uwalnia się eten, który stanowi składnik mierzony uzyskiwanej gazowej mieszaniny wzorcowej. Ilość uwalnianego etenu zależy jedynie od długości danego rodzaju i typu modyfikowanego włókna...
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Evaluation of headspace solid-phase microextraction for the analysis of volatile carbonyl compounds in spirits and alcoholic beverages
PublicationOpracowano metodę oznaczania C1-C6 związków karbonylowych w układzie GC-ECD w roztworach alkoholowych poprzez derywatyzację pentafluorobenzylohydroksy-aminą i mikroekstrakcję w fazie stacjonarnej z fazy nadpowierzchniowej. Zoptymalizowano warunki eksperymantalne: zawartość alkoholu, czas ekspozycji, temperaturę i sposób mieszania próbki. W metodzie tej najpierw przeprowadza się rozcieńczenie spirytusu lub napojów alkoholowych do...
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Metal-coated fused silica fibers as a support for immobilized compounds yielding a volatile analyte (C2H4)
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