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Wyniki wyszukiwania dla: FORMALDEHYD
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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...
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Hydrophobic and hydrophilic properties of pollutants as a factor influencing their redistribution during snowpack melt
PublikacjaGlaciers accumulate organic pollutants delivered by snow. However, our understanding of the exact dynamics of organic pollutants in the snowpack relies primarily on laboratory experiments and mathematical models. To fill the gap related to the detailed field data, we have conducted observations of melting snow profiles in two locations and three different stages of melting on one High Arctic glacier, as well as in superimposed...
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Comparison of hydrochemistry and organic compound transport in two non-glaciated high Arctic catchments with a permafrost regime (Bellsund Fjord, Spitsbergen)
PublikacjaAn increase in air temperature related to climate change results in the retreat of glaciers, the degradation of permafrost, and the expansion of glacier-free areas in the polar regions. All these processes lead to changes in the Arctic landscape. They influence the hydrochemistry of streams and rivers fed by glaciers and thawing permafrost. In this study, we examine eighty two water samples from two non-glaciated catchments with...
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Environmental characteristics of a tundra river system in Svalbard. Part 2: Chemical stress factors
PublikacjaBacterial communities in the Arctic environment are subject to multiple stress factors, including contaminants, although typically their concentrations are small. The Arctic contamination research has focused on persistent organic pollutants (POPs) because they are bioaccumulative, resistant to degradation and toxic for all organisms. Pollutants have entered the Arctic predominantly by atmospheric and oceanic long-range transport,...
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Pollutant deposition via dew in urban and rural environment, Cracow, Poland
PublikacjaThis study is a comparative analysis of dew in rural and urban environment. Dew samples were collected between May and October, 2009 in two reference stations in southern Poland: Cracow and Gaik-Brzezowa. The investigation included comparison of volume and chemistry of the collected samples. Due to its formation mechanisms, dew is a good indicator of air pollution. Following parameters were analyzed in 159 collected samples: pH,...
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The interaction between bacterial abundance and selected pollutants concentration levels in an arctic catchment (southwest Spitsbergen, Svalbard)
PublikacjaPersistent organic pollutants (POPs) have been a topic of interest in environmental sciences for > 60 years. POPs in the Arctic have been investigated since the 1970s, when first atmospheric measurements revealed the presence of these pollutants in the polar regions. Major contaminant transport routes to the Arctic include atmospheric and oceanic transport, as well as inflow from rivers and sea ice. The sources of pollutants, such...
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H2O˙+ and OH+ reactivity versus furan: experimental low energy absolute cross sections for modeling radiation damage
PublikacjaRadiotherapy is one of the most widespread and efficient strategies to fight malignant tumors. Despite its broad application, the mechanisms of radiation-DNA interaction are still under investigation. Theoretical models to predict the effects of a particular delivered dose are still in their infancy due to the difficulty of simulating a real cell environment, as well as the inclusion of a large variety of secondary processes. This...
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Osady atmosferyczne jako wskaźnik oceny stopnia zanieczyszczenia powietrza atmosferycznego
PublikacjaCelem badań, realizowanych w ramach pracy doktorskiej, było określenie poziomu stężeń szeregu toksycznych składników śladowych obecnych w próbkach osadów atmosferycznych zbieranych na terenie wytypowanych aglomeracji miejskich wyraźnie różniących się pod względem położenia geograficznego jak również poziomu antropopresji. Realizację tak zaplanowanego projektu badawczego umożliwiła ocena przydatności stosowanych już w praktyce metodyk...
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Investigation of RH effect on uncommon limonene ozonolysis products and SOA formation in indoor air with real time measurement techniques
PublikacjaScientific interest in SOA influence on indoor air quality increases since last 20 years. It is well known, that particles of nano-sized diameter pose a threat for human health causing, among others: eye, upper airway irritation, inflammatory response in cells, worsening asthma, hypertension, diabetes, and central nervous dysfunction. Terpenes are reactive VOCs, commonly emitted in indoor air and considered to be SOA precursors...
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Concentrations and loads of DOC, phenols and aldehydes in a proglacial arctic river in relation to hydro-meteorological conditions. A case study from the southern margin of the Bellsund Fjord – SW Spitsbergen
PublikacjaClimate warming accelerates the melting and thawing of cryosphere components. Therefore, it favours the release of contaminants stored in High-Arctic glaciers for many years. The rate of land-based glacier retreat is of particular importance for the hydrological regime of glacial rivers, but also for the chemical composition of their waters. In this study, we examined 84 surface water samples collected during a period of 42 days...
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Pokrywa śnieżna jako źródło informacji o zanieczyszczeniu środowiska (na przykładzie wyników badań próbek śniegu z Sudetów Zachodnich i Arktyki)
PublikacjaPokrywa śniegowa stanowi medium bardzo dynamiczne. Zarówno fizyczne, jak i chemiczne procesy mogą wpływać na zmianę jej składu chemicznego, dlatego powinny być prowadzone wszechstronne badania składu zanieczyszczeń zawartych w śniegu. Skład chemiczny warstw śniegowych jest odbiciem składu rodzimych aerozoli atmosferycznych, suchego opadu oraz charakteru powierzchni adsorbującej. Akumulacja składników występujących w atmosferze...