Fant 9758 publikasjoner. Viser side 326 av 391:
Norsk institutt for naturforskning (NINA)
2021
Overvåking av langtransporterte atmosfæriske miljøgifter i luft og nedbør, årsrapport 2020.
Denne rapporten inkluderer miljøovervåkningsdata fra 2020 og tidstrender for programmet Langtransporterte atmosfæriske miljøgifter. Resultatene omfatter 200 organiske miljøgifter (regulerte og ennå ikke regulerte), 11 tungmetaller og et utvalg organiske kjemikalier som potensielt er av bekymring for Arktisk miljø.
NILU
2021
Micronucleus assay applied to advanced in vitro lung models at ALI for nanotoxicity assessment
Elsevier
2021
The influence of probe spacing and probe bias in a double Langmuir probe setup
Multi-needle Langmuir probes are mounted on satellites and sounding rockets for high-frequency characterization of plasma in the ionosphere. Mounted on a spacecraft, the recorded probe current often differs from expected results. In this paper, we perform a numerical study using a particle in cell model to see how the spacing between the individual probes used in a multi-needle setup influences the measured current. We also study how the applied probe bias voltage can contribute to deviations. In our study, we use realistic electron temperatures and electron densities for the relevant part of the ionosphere. However, the results should be generally applicable and valid for other space environments as well as for laboratory Langmuir probe applications. From our study, we can see that when the distance is short, less than two Debye lengths, the current is highly affected, and we can see deviations of more than 60% compared to a single probe setup.
AIP Publishing (American Institute of Physics)
2021
2021
Calibration of CO, NO2, and O3 Using Airify: A Low-Cost Sensor Cluster for Air Quality Monitoring
MDPI
2021
2021
The report evaluates current mapping methodology with respect to city- and NUTS3-levels mapping across Europe. It states that the current mapping can be used at the city and the NUTS3 levels, despite a mild smoothing effect at locations of the measurement stations. However, it suggests a post-processing correction based on the mapping residuals.
A potential new approach for the city ranking have been examined, namely the population-weighted concentration based on the mapping results. While the averaged measurement data from the background stations (as used in the current city ranking) provides a superior information for the whole city in general, the population-weighted concentration also well represents the whole city and gives a consistent information for all cities, including those without station measurements.
Next to this, alternative treatments of rural and urban stations has been evaluated. If the urban traffic areas should be better represented in the final maps, an increased map resolution is recommended.
Several possibilities of future development towards the European-wide city level mapping in a fine resolution have been suggested, namely exploitation of a high-resolution model output in the existing methodology, geostatistical downscaling of the existing spatial maps using fine-resolution proxy datasets and exploitation of existing low-cost sensor networks.
ETC/ATNI
2021
2021
Introducing a nested multimedia fate and transport model for organic contaminants (NEM)
Some organic contaminants, including the persistent organic pollutants (POPs), have achieved global distribution through long range atmospheric transport (LRAT). Regulatory efforts, monitoring programs and modelling studies address the LRAT of POPs on national, continental (e.g. Europe) and/or global scales. Whereas national and continental-scale models require estimates of the input of globally dispersed chemicals from outside of the model domain, existing global-scale models either have relatively coarse spatial resolution or are so computationally demanding that it limits their usefulness. Here we introduce the Nested Exposure Model (NEM), which is a multimedia fate and transport model that is global in scale yet can achieve high spatial resolution of a user-defined target region without huge computational demands. Evaluating NEM by comparing model predictions for PCB-153 in air with measurements at nine long-term monitoring sites of the European Monitoring and Evaluation Programme (EMEP) reveals that nested simulations at a resolution of 1° × 1° yield results within a factor of 1.5 of observations at sites in northern Europe. At this resolution, the model attributes more than 90% of the atmospheric burden within any of the grid cells containing an EMEP site to advective atmospheric transport from elsewhere. Deteriorating model performance with decreasing resolution (15° × 15°, 5° × 5° and 1° × 1°), manifested by overestimation of concentrations across most of northern Europe by more than a factor of 3, illustrates the effect of numerical diffusion. Finally, we apply the model to demonstrate how the choice of spatial resolution affect predictions of atmospheric deposition to the Baltic Sea. While we envisage that NEM may be used for a wide range of applications in the future, further evaluation will be required to delineate the boundaries of applicability towards chemicals with divergent fate properties as well as in environmental media other than air.
Royal Society of Chemistry (RSC)
2021
2021
Ftalater er organiske stoffer som hovedsakelig brukes til å gjøre plast mykere, særlig i PVC. Produksjonen av disse forbindelsene er ikke regulert på globalt nivå. Vi undersøkte nivåer av 12 ftalater i fett/spekk fra blåhval, finnhval, grønlandshval og isbjørn fra norsk Arktis. I tillegg målte vi nivåer av nedbrytningsprodukter av ftalater i plasma fra isbjørn. Bis(2-etylhexyl) ftalat (DEHP) var den eneste ftalat-forbindelsen som ble kvantifisert i prøvene. DEHP var til stede i de fleste hvalprøvene og nivåene i blå- og finnhvalspekk var lik nivåer av kjente miljøgifter som PCBer og organiske plantevernmidler. Nedbrytningsprodukter av ftalater ble funnet i lave konsentrasjoner i noen få isbjørnprøver. I tillegg undersøkte vi ftalaters potensial til å forstyrre finnhvalenes kjernereseptorer. Kjernereseptorer er proteiner som regulerer gener. De studerte reseptorene er viktige for å regulere blant annet metabolisme, stressresponser og energibalanse. Vi fant at DEHP både kan øke og hemme aktiviteten til skjoldbruskkjertelhormonreseptor, men da i høyere konsentrasjoner enn det som ble målt i spekk-/fettprøvene. Siden de studerte finnhvalreseptorene er helt eller nesten like de som finnes hos mange andre arter inkludert blåhval, vågehval, spekkhoggere, hvithval, isbjørn og mennesker, er resultatene også relevante for disse artene. Dette studiet bidrar til å øke kunnskapen om plastrelaterte stoffer og deres potensial til å forstyrre hormonsystemet hos marine pattedyr fra norsk Arktis.
Elsevier
2021
2021
2021
2021
American Geophysical Union (AGU)
2021
BioMed Central (BMC)
2021