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Wyniki wyszukiwania dla: FORMALDEHYD
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Recent progress in ultra-low formaldehyde emitting adhesive systems and formaldehyde scavengers in wood-based panels: a review
PublikacjaTraditional wood-based panels are produced with synthetic, formaldehyde-based adhesives, commonly made from fossil-derived constituents, such as urea, phenol, melamine, etc. Along with their numerous advantages, such as chemical versatility, high reactivity and excellent adhesive performance, these adhesives are characterized by certain problems, connected with the hazardous volatile organic compounds (VOCs), mostly free formaldehyde...
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Formaldehyde in Human Saliva as an Indication of Environmental Tobacco Smoke Exposure
PublikacjaSkład środowiskowego dymu tytoniowego zależy przede wszystkim od stosowanej odmiany tytoniu oraz różnorodnych dodatków wprowadzanych do tytoniu na etapie produkcji papierosów. Podczas palenia tytoniu węglowodany ulegają złożonym przemianom, w wyniku których powstają toksyczne składniki środowiskowego dymu tytoniowego, w szczególności aldehydy (formaldehyd). Celem badań było uzyskanie informacji o poziomie zawartości formaldehydu...
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The formation of formaldehyde via the carbon monoxide hydrogenation catalyzed by the HSbF6 superacid
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Synthesis and characterization of resorcinol–formaldehyde resin chars doped by zinc oxide
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Chemical modification of tannins from Acacia mearnsii to produce formaldehyde free flocculant
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Effect of nanosilica on characteristics of carbonizates of phenol-formaldehyde resin – Fe(acac)3
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Release and Transport of Toxic, Mobile Organic Compounds (Formaldehyde and Phenols) on an Arctic Glacier
PublikacjaAs a result of current deglaciation, the chemical cycles of many compounds, including toxic formaldehyde and phenols, are changing. However, the processes by which these chemicals are released have yet to be studied in situ. Here, we quantify fluxes of HCHO and phenols in a glacial catchment within one summer season, obtaining a net release from the glacier of 0.106 · 106 g formaldehyde and 0.255 · 106 g phenols, which can be interpreted...
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Slurry Surfacing Mixes on the Basis of Bitumen Modified with Phenol-Cresol-Formaldehyde Resin
PublikacjaSlow-breaking monophase cationic bitumen emulsions have been produced on the basis of bitumen modified with phenol-cresol-formaldehyde resin (PhCR-F). Bitumen emulsions were used as a binder for thin-layer coatings with slurry surfacing mixes (SSM). Physical and technical parameters of modified and unmodified emulsions were determined and analyzed. The optimal compositions of SSM were selected according to the breaking criterion....
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Formaldehyde in various forms of atmospheric prepicitation and deposition from highly urbanized regions
PublikacjaOznaczono stężenie formaldehydu w próbkach różnych form opadów i osadów atmosferycznych pobieranych przez okres 12 miesięcy, w trakcie występowania opadu lub osadu atmosferycznego lub tuż po jego ustąpieniu, na terenie dwóch aglomeracji miejskich i wzdłuż dróg o różnym natężeniu ruchu. Formaldehyd wykryto w 303 próbkach z 500 pobranych (stężenia od 0.05 do 10.7 mg/dm3). Wyniki analiz potwierdziły iż:- opady i osady atmosferyczne...
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Cross-linking of epoxy-oligomeric mixtures in the presence of modified phenol-formaldehyde resins
PublikacjaCross-linking of epoxy oligomeric mixtures consisting of industrial epoxy resin ED-20, oligoetheracrylate TGM-3, peroxide derivative of epoxy resin ED-24 and phenol-formaldehyde oligomer with unsaturated methacrylate fragments or peroxide groups was studied in the presence of polyethylenepolyamine at room temperature and heated to 383, 403 or 423 K for 15, 30, 45, 60 and 75 minute. The influence of mixture composition, temperature...
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Nickel Oxide Thin Film Sensor for Fluctuation-Enhanced Gas Sensing of Formaldehyde
PublikacjaNanocrystalline nickel-oxide-based thin films were prepared by advanced reactive gas deposition, and the response of these films to formaldehyde was studied by fluctuationenhanced sensing. Morphological and structural analyses showed porous deposits of nickel oxide particles with face-centered cubic structure. Resistance fluctuations were measured upon exposure to ethanol, formaldehyde and methane at 200 °C. Power density spectra...
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Catalytic aldol condensation of formaldehyde with acetic acid on titanium phosphates modified by different techniques
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Determination of Formaldehyde and Cyanide Ion in Human Nasal Discharge by Using Simple Spectrophotometric Methods
PublikacjaEnvironmental tobacco smoke (ETS) contains many toxic compounds which include substances classified as aldehydes (e.g. formaldehyde) and inorganic substances such as cyanide ions. The information on the determination of these compounds in water is available, but the monitoring data on the level of these substances in human body fluids are still lacking. In this work the procedure for determining cyanide ions and formaldehyde in...
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Cross-linking of polymer films using phenol-formaldehyde resins with different functional groups
PublikacjaWell-know phenol-formaldehyde resins are used in the production of press-materials, glues, protective coating, mastics. They take a special place among known oligomers because the products based on them are characterized by a low cost and a series of positive properties. Aim of the work: to show the possibility to create polymeric films based on epoxy resins and modified phenol-formaldehyde resins, which contain unsaturated double...
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Formaldehyd w różnych formach opadów i osadów atmosferycznych na terenach o wysokim stopniu zurbanizowania
PublikacjaNajwiększy udział w dostawie zanieczyszczeń z atmosfery do powierzchni ziemi w regionach położonych w znacznych odległościach od źródeł emisji ma depozycja mokra. Opady atmosferyczne będące produktem kondensacji pary wodnej zawartej w atmosferze, na skutek adiabatycznego ochładzania się powietrza, opadają na powierzchnię ziemi (deszcz, śnieg, mżawka, krup, grad), unoszą się w powietrzu (mgła) albo osiadają (rosa, szron, szadź)....
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Stężenie formaldehydu w wodach spływnych z arterii komunikacyjnych, powierzchni dachów budynków i koron drzew, wodach gruntowych i rzecznych oraz w opadach i osadach atmosferycznych na terenie aglomeracji miejskich = Formaldehyde in road runoff, roof runoff, ground water, river, atmospheric precipitation and deposition from highly urbanized regions
PublikacjaOznaczono stężenie formaldehydu w próbkach wód opadowych, spływnych z arterii komunikacyjnych, powierzchni dachów budynków i koron drzew, wód gruntowych i cieków wodnych oraz w próbkach śniegu, szronu i sadzi. Próbki pobierano przez okres 7 miesięcy w trakcie wystąpienia opadu lub osadu atmosferycznego lub tuż po jego ustąpieniu. Pomiar zawartości formaldehydu wykonywano stosując metodę szybkich testów spektrofotometrycznych w...
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Studies on the formation of formaldehyde during 2-ethylhexyl 4-(dimethylamino)benzoate demethylation in the presence of reactive oxygen and chlorine species
PublikacjaIn order to protect the skin from UV radiation, personal care products (PCPS) often contain chemical UV-filters. These compounds can enter the environment causing serious consequences on the water ecosystems. The aim of this study was to examine, the effect of different factors, such as UV light, the presence of NaOCl and H2O2 on the formaldehyde formation during popular UV filter, 2-ethylhexyl 4-(dimethylamino)benzoate (ODPABA)...
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Novel porous carbon/clay nanocomposites derived from kaolinite/resorcinol-formaldehyde polymer blends: synthesis, structure and sorption properties
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Mechanisms of carbon monoxide hydrogenation yielding formaldehyde catalyzed by the representative strong mineral acid, H2SO4, and Lewis–Brønsted superacid, HF/AlF3
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Formaldehyde detection with chemical gas sensors based on WO3 nanowires decorated with metal nanoparticles under dark conditions and UV light irradiation
PublikacjaWe report results of formaldehyde gas (CH2O) detection under dark conditions and UV light irradiation with pristine tungsten trioxide nanowires (WO3 NWs) and metal nanoparticles decorated WO3 NWs gas sensing layers. The resistive layers were deposited by one step aerosol assisted chemical vapor deposition (AACVD) on commercial alumina substrates with 10-pair interdigitated platinum electrodes. The elaborated gas sensors, based...
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Textural Characteristics of Resorcinol—Formaldehyde Resin and Temperature Behavior of Bound Water Affected by Co-Adsorbed Trifluoroacetic Acid or Pyridine in Weakly Polar Organic Media
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Fluctuation-enhanced and conductometric gas sensing with nanocrystalline NiO thin films: A comparison
PublikacjaNanocrystalline thin films of NiO were prepared by advanced reactive gas deposition, and their responses to formaldehyde, ethanol and methane gases were studied via fluctuation-enhanced and conductometric methods Thin films with thicknesses in the 200–1700-nm range were investigated in as-deposited form and after annealing at 400 and 500 °C. Morphological and structural analyses showed porous deposits with NiO nanocrystals having...
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Fluctuation-Enhanced Sensing with Organically Functionalized Gold Nanoparticle Gas Sensors Targeting Biomedical Applications
PublikacjaDetection of volatile organic compounds is a useful approach to non-invasive diagnosis of diseases through breath analysis. Our experimental study presents a newly developed prototype gas sensor, based on organically-functionalized gold nanoparticles, and results on formaldehyde detection using fluctuation-enhanced gas sensing. Formaldehyde was easily detected via intense fluctuations of the gas sensor’s resistance, while the cross-influence...
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Application of chemometric approach in studies of dew chemistry (on the basis of samples collected in Poland)
PublikacjaPrzedstawiono wyniki badań wybranych związków chemicznych (aniony, kationy, formaldehyd, nadtlenek wodoru, suma fenoli, TC, TIC, TOC) oznaczonych w próbkach rosy zebranych z różnych obszarów na terenie Polski (Gdynia, Gdańsk, Sopot, Mława, Kraków). Zastosowano analizę funkcji dyskryminacyjnej aby dokonać klasyfikacji poszczególnych próbek w zależności od miejsca pobierania oraz wykryć podstawowe zależności pomiędzy poszczególnymi...
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Determination of selected chemical parameters in surface water samples collected from the Revelva catchment (Hornsund fjord, Svalbard)
PublikacjaSurface water samples (river and lake) were collected from the Revelva catchment every summer from 2010 to 2013. This study concerns importance of the use of some analytical techniques for pollutants and parameters deter- mination in Arctic environmental samples based on the example of total organic carbon, phenols, and formaldehyde determination and measurement of pH and electrical conductivity parameters. Significant...
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Non-Gaussian Resistance Fluctuations in Gold-Nanoparticle-Based Gas Sensors: An Appraisal of Different Evaluation Techniques
PublikacjaVolatile organic compounds, such as formaldehyde, can be used as biomarkers in human exhaled breath in order to non-invasively detect various diseases, and the same compounds are of much interest also in the context of environmental monitoring and protection. Here, we report on a recently-developed gas sensor, based on surface-functionalized gold nanoparticles, which is able to generate voltage noise with a distinctly non-Gaussian...
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Dynamics of changes in the concentration levels of organic pollutants in the proglacial waters of the Scott River (Spitsbergen, SW Svalbard)
PublikacjaThe study area covered the NW part of the Wedel Jarlsberg Land. The present study concerns participation of organic pollutants inflow from glacier and seaside plane of Calypsostranda to proglacial waters of the Scott River due to occurrence of precipitation. Concentration ranges for phenols and formaldehyde in water samples are respectively:
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A prototype of electrochemical sensor for measurement of carbonyl compounds in air
PublikacjaThe paper presents the results of investigation on a prototype sensor for measurement of benzaldehyde and formaldehyde in air. Sensitivity, limit of quantification and coefficient of selectivity of the sensor have been determined as a function of membrane thickness and electrode type using square wave voltammetry (SWV) technique. The working and counter electrodes were made of platinum and gold. Ionic liquids 1-hexyl, 3-methylimidazolium...
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Generation of hydroxyl radicals in UV/TiO2 and UV/H2O2 systems
PublikacjaPrzeprowadzono badania efektywności generowania rodników hydroksylowych dla różnych warunkow fotokatalitycznego utleniania. Rodniki hydroksylowe oznaczano pośrednią metodą utleniania metanolu, w której następuje spektrofotometryczne oznaczenie powstałego formaldehydu po derywatyzacji z 2,4-dinitrofenylohydrazyną. Badania wykazały, że wzrost pH zwiększa efektywność generowania ·OH zarówno w układzie hetero- i homogenicznym....
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Electrochemical sensor for measurement of volatile organic compounds in air
PublikacjaPrzedstawiono 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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The Research of the Contamination Levels present in Samples of Precipitation and Surface Waters Collected from the Catchment Area Fuglebekken (Hornsund, Svalbard Archipelago)
PublikacjaPersistent organic pollutants (POPs) are contaminants that may appear in polar regions. In present work surface water was collected from the main stream water in the Fuglebekken basin. The precipitationsamples was collected from the near area by Polish Polar Station in Hornsund. The present investigationreveals the results of the analysis of these samples for their total phenols, formaldehyde, TOC, PAHs and PCBs content. The...
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Electrochemical sensor for measurement of volatile organic compounds = Elektrochemiczny czujnik do oznaczania lotnych związków organicznych
PublikacjaPrzedstawiono rezultaty badań prototypowego czujnika do oznaczania benzaldehydu i formaldehydu w powietrzu. Określono czułość wskazań czujnika i jego granice oznaczalności wykorzystując jako technikę detekcyjną woltamperometrię fali prostokątnej (SWV). Elektrodę roboczą i przeciwelektrodę stanowiły elektrody z Pt. Elektrolitem wewnętrznym były ciecze jonowe: chlorek 1-heksylo,3- metyloimidazolinowy i bis(trifluorometylosulfonylo)imidek...
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Fluctuation enhanced gas sensing with WO3-based nanoparticle gas sensors modulated by UV light at selected wavelengths
PublikacjaThe sensitivity and selectivity of WO3-based gas sensors can be enhanced by UV-irradiation-induced modulation, especially if different wavelengths are employed. We used fluctuation-enhanced gas sensing, based on measurements of resistance fluctuations in the gas sensor, to study the effects of such modulation on the noise intensity for ambient atmospheres of synthetic air without and with additions of small amounts of ethanol,...
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Drinking water safety evaluation in the selected sub-Saharan African countries: A case study of Madagascar, Uganda and Rwanda
PublikacjaIn the sub-Saharan region of Africa, access to safe drinking water remains limited in many countries. This study provides an overview of the quality of surface water and groundwater in rural and peri-urban areas of Madagascar, Uganda, and Rwanda. Selected physico-chemical parameters, inorganic species (including inorganic ions), and organic pollution indicators, such as total organic carbon, non-ionic surfactants, cationic surfactants, anionic...
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Determination of selected parameters/ analytes in surface water samples collected in the surroundings of the capital of Spitsbergen (Longyearbyen)
PublikacjaPolar regions are extremely sensitive to pollution such as harmful gases, particles or toxic substances which affect the Arctic climate and ecosystems. Spitsbergen, as well as all Arctic region, because of its geographically distant location and lack of industry sector, should be free of chemical pollution. Despite this, many pollutants could be found in the Polar environment, for example in freshwaters. Their occurrence is related...
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Determination of Odour Interactions of Three-Component Gas Mixtures Using an Electronic Nose
PublikacjaThe paper presents an application of an electronic nose prototype comprised of six TGS-type sensors and one PID-type sensor to identify odour interaction phenomena in odorous three-component mixtures. The investigation encompassed eight odorous mixtures—toluene-acetone-triethylamine and formaldehyde-butyric acid-pinene — characterized by different odour intensity and hedonic tone. A principal component regression (PCR) calibration...
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Contamination of Arctic Lakes with Persistent Toxic PAH Substances in the NW Part of Wedel Jarlsberg Land (Bellsund, Svalbard)
PublikacjaThe expansion of glacier‐free areas in polar regions favours the appearance of lakes in the non‐glaciated parts of glacier basins. This paper presents the differentiation of organic compound concentrations in fifty‐four Arctic lakes collected in four locations (Logne Valley, in the vicinity of the Scott, Renard and Antonia glaciers). We cover meteorological measurements, chemical analysis of sixteen dioxin‐like compounds (Polycyclic...
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HS-SPME-CGC-PID determination of aldehydes in rectified spirits and vodkas after derivatisation with 2,4,6-trichlorophenylhydrazine (TCPH)
PublikacjaW pracy przedstawiono nową metodę oznaczania aldehydów w spirytusach i wyrobach spirytusowych czystych z zastosowaniem 2,4,6-trichlorofenylohydrazyny (TCPH) jako odczynnika derywatyzującego. Zaproponowana metoda jest co najmniej 100-krotnie tańsza od mikroekstrakcji do fazy stacjonarnej z fazy nadpowierzchniowej (HS-SPME) i chromatografii gazowej z zastosowaniem często zalecanej o-2,3,4,5,6-pentafluorobenzylohydroxyloaminy (PFBHA)....
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Recycling of Polyurethanes Containing Flame-Retardants and Polymer Waste Transformed into Flame-Retarded Polyurethanes
PublikacjaThe growing number of polyurethanes (PUs) produced every year has developed methods for their mechanical and chemical recycling which yield valuable products like substitutes for commercial polyols or flame-retardants. PUs can be produced in different shapes and forms (i.e., elastomers, flexible or rigid foams, coatings, etc.) using several different components (i.e., di- or polyisocyanates, ester- or ether-based polyols, low-molecular...
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Evaluation of Health Hazard Due to Emission of Volatile Organic Compounds from Various Processing Units of Wastewater Treatment Plant
PublikacjaThe paper describes an attempt at health risk assessment and odour concentration determination in the most important units of a wastewater treatment plant. The cancer risk (CR) and hazard index (HI) parameters in selected measurement locations were calculated based on the results of chromatographic analyses (GCxGC-TOF-MS) and the United States Environmental Protection Agency (US EPA) guidelines. No exceedance of the CR and HI acceptable...
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Analysis of odour interactions in model gas mixtures using electronic nose and fuzzy logic
PublikacjaMeasurement and monitoring of air quality in terms of odour nuisance is an important problem. Although the source of these nuisances is different (e.g. wastewater treatment plants, municipal landfills), their common feature is that they are a complex mixture of odorants with different odour thresholds. An additional problem is occurrence of the odour interactions between mixture components. From a practical point of view, it would...
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Contaminants in airport runoff water in the Vicinities of Two International Airports in Poland
PublikacjaThe general aim of the study was to evaluate environmental quality associated with the operations (combustion of fuels, cleaning of aircraft and airport aprons, aircraft, ground vehicle maintenance and repairs, fuelling operations, de/anti-icing operations) of international airports located in central and northern of Poland. These two monitoring areas were set up to monitor PAHs, PCBs, formaldehydes, phenols, detergents (cationic,...
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Wykorzystanie różnych form opadów i osadów atmosferycznych do oceny zanieczyszczenia środowiska w różnych regionach geograficznych Polski - część II - rosa = Various forms of atmospheric precipitation and deposits as a measure of environmental pollution in different geographic regions of Poland - part II - dew
PublikacjaW ramach pracy przeprowadzono analizy 235 próbek rosy i 65 próbek deszczu zebranych na 8 stacjach na terenie Polski w okresie od sierpnia 2004 do listopada 2006 roku. W zależności od położenia oraz charakteru tła emisji zanieczyszczeń stacje pogrupowano na: rolnicze (Wrocław, Dziemiany); miejskie w strefie wybrzeża (Gdańsk, Gdynia, Sopot); miejskie, położone poza strefą wybrzeża (Bytów, Kraków, Mława) Próbki opadu i osadu atmosferycznego...
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Analytics of dew and fog samples - problems and challenges
PublikacjaBadania analityczne próbek mgły i rosy mogą dostarczyć wielu interesujących informacji o stanie powietrza atmosferycznego i procesów, które w nim zachodzą. Badania takie stanowią jednak poważne wyzwanie analityczne m.in. ze względu na: konieczność dysponowania odpowiednimi urządzeniami do pobierania próbek, małe objętości próbek jakie udaje się zebrać w określonym czasie, co w istotnym stopniu determinuje wybór techniki ich przygotowania...
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Wykorzystanie różnych form opadów i osadów atmosferycznych do oceny zanieczyszczenia środowiska w różnych regionach geograficznych Polski. Część III - szron i sadź = Various forms of atmosheric precipitaion and deposits as a measure of environmental pollution in different geographic regions of Poland. Part III - Hoarfrost and rime.
PublikacjaW ramach pracy przedstawiono badania dotyczące oznaczenia stężeń wybranych związków nieorganicznych i organicznych w próbkach szronu i sadzi. Próbki pobierano w dziewięciu punktach na terenie całej Polski. Miejsca pobierania próbek podzielono ze względu na ich różny charakter: teren wiejski, teren miejski w głębi lądu oraz wybrzeże o charakterze miejskim (szron); szczyt górski, kotlina górska oraz wybrzeże o charakterze miejskim...
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Toxicity and chemical analyses of airport runoff waters in Poland
PublikacjaThe aim of this study was to assess the ecotoxicological effects of various compounds in complex airport effluents using a chemical and ecotoxicological integrated strategy. The present work deals with the determination of sum of PCBs, PAHs, pesticides, cations, anions, phenols, anionic, cationic, non-ionic detergents, formaldehyde and metals – as well as TOC and conductivity – in runoff water samples collected from 2009 to 2011...
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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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First evaluation of wastewater discharge influence on marine water contamination in the vicinity of Arctowski Station (Maritime Antarctica)
PublikacjaIn Antarctica,waste is generatedmainly during scientific research programmes and related logistics. In this study, the impact ofwastewater on the western shore of Admiralty Baywas investigated during austral summer in 2017 and 2019. A range of physicochemical parameters and the presence of selected trace metals, formaldehyde and different groups of surfactants were determined in wastewater coming from Arctowski Station and in nearby coastal...
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N-doped carbon nanospheres as selective fluorescent probes for mercury detection in contaminated aqueous media: chemistry, fluorescence probing, cell line patterning, and liver tissue interaction
PublikacjaA precise nano-scale biosensor was developed here to detect Hg2+ in aqueous media. Nitrogen-doped carbon nanospheres (NCS) created from the pyrolysis of melamine–formaldehyde resin were characterized by FESEM, XRD, Raman spectra, EDS, PL, UV–vis spectra, and N2 adsorption–desorption, and were used as a highly selective and sensitive probe for detecting Hg2+ in aqueous media. The sensitivity of NCS to Hg2+ was evaluated by photoluminescence...
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Electronically Excited States in Solution via a Smooth Dielectric Model Combined with Equation-of-Motion Coupled Cluster Theory
PublikacjaWe present a method for computing excitation energies for molecules in solvent, based on the combination of a minimal parameter implicit solvent model and the equation-of-motion coupled-cluster singles and doubles method (EOM-CCSD). In this method, the solvent medium is represented by a smoothly varying dielectric function, constructed directly from the quantum mechanical electronic density using only two tunable parameters. The...