Fant 9747 publikasjoner. Viser side 9 av 390:
2004
2011
2016
VETAPOS. Faglig sammendrag. NILU OR
I flere rapporter og publikasjoner er det påpekt at lokal utslipp av forurensning har potensial for betydelige miljøpåvirkninger på Svalbard. Et fagarbeid rundt utslipp i sterkt trafikkerte områder i Longyearbyen påviser store mengder av flyktige forurensinger fra bil- og snøscootereksos med mulig effekt på mennesker og natur (Reimann et al. 2009).
Polysykliske aromatiske hydrokarboner (PAH) er tjærestoffer som slippes ut gjennom forbrenningsprosesser av fossil brensel. Disse stoffene finnes også i geologiske formasjoner med høy andel av organisk materiale (som kull, petroleum etc.). Å undersøke fordeling av disse stoffene i miljøprøver (jord, sediment) kan avsløre om PAH er av naturlig opprinnelse (petrogen) eller stammer fra utslipp fra motorer (bensin, diesel) eller annet fossilt brensel (pyrogen). Sammen med VOC-forbindelser, som raskt nedbrytes i miljøet er PAH en velegnet stoffgruppe for å identifisere og karakterisere uslipp fra fossilt brensel til miljøet.
2011
Atmospheric methane grew very rapidly in 2014 (12.7 ± 0.5 ppb/year), 2015 (10.1 ± 0.7 ppb/year), 2016 (7.0 ± 0.7 ppb/year), and 2017 (7.7 ± 0.7 ppb/year), at rates not observed since the 1980s. The increase in the methane burden began in 2007, with the mean global mole fraction in remote surface background air rising from about 1,775 ppb in 2006 to 1,850 ppb in 2017. Simultaneously the 13C/12C isotopic ratio (expressed as δ13CCH4) has shifted, has shifted, now trending negative for more than a decade. The causes of methane's recent mole fraction increase are therefore either a change in the relative proportions (and totals) of emissions from biogenic and thermogenic and pyrogenic sources, especially in the tropics and subtropics, or a decline in the atmospheric sink of methane, or both. Unfortunately, with limited measurement data sets, it is not currently possible to be more definitive. The climate warming impact of the observed methane increase over the past decade, if continued at >5 ppb/year in the coming decades, is sufficient to challenge the Paris Agreement, which requires sharp cuts in the atmospheric methane burden. However, anthropogenic methane emissions are relatively very large and thus offer attractive targets for rapid reduction, which are essential if the Paris Agreement aims are to be attained.
PLAIN LANGUAGE SUMMARY: The rise in atmospheric methane (CH4), which began in 2007, accelerated in the past 4 years. The growth has been worldwide, especially in the tropics and northern midlatitudes. With the rise has come a shift in the carbon isotope ratio of the methane. The causes of the rise are not fully understood, and may include increased emissions and perhaps a decline in the destruction of methane in the air. Methane's increase since 2007 was not expected in future greenhouse gas scenarios compliant with the targets of the Paris Agreement, and if the increase continues at the same rates it may become very difficult to meet the Paris goals. There is now urgent need to reduce methane emissions, especially from the fossil fuel industry.
American Geophysical Union (AGU)
2019
2011
2014
2005
2018
ThermoFisher Scientific
2018
We describe the outcome of a large international interlaboratory study of the measurement of particle number concentration of colloidal nanoparticles, project 10 of the technical working area 34, “Nanoparticle Populations” of the Versailles Project on Advanced Materials and Standards (VAMAS). A total of 50 laboratories delivered results for the number concentration of 30 nm gold colloidal nanoparticles measured using particle tracking analysis (PTA), single particle inductively coupled plasma mass spectrometry (spICP-MS), ultraviolet-visible (UV-Vis) light spectroscopy, centrifugal liquid sedimentation (CLS) and small angle X-ray scattering (SAXS). The study provides quantitative data to evaluate the repeatability of these methods and their reproducibility in the measurement of number concentration of model nanoparticle systems following a common measurement protocol. We find that the population-averaging methods of SAXS, CLS and UV-Vis have high measurement repeatability and reproducibility, with between-labs variability of 2.6%, 11% and 1.4% respectively. However, results may be significantly biased for reasons including inaccurate material properties whose values are used to compute the number concentration. Particle-counting method results are less reproducibile than population-averaging methods, with measured between-labs variability of 68% and 46% for PTA and spICP-MS respectively. This study provides the stakeholder community with important comparative data to underpin measurement reproducibility and method validation for number concentration of nanoparticles.
Royal Society of Chemistry (RSC)
2022
Verifisering av skorsteinshøyder i forbindelse med utvidelse av aluminiumsmelteverket på Karmøy. NILU rapport
Beregninger for spredning av utslipp fra Karmøy Aluminiumverk er gjennomført for samlede utslipp fra et utvidet verk. Beregningene viser at grenseverdier for konsentrasjoner i omgivelsene overholdes med unntak av utslipp av hydrogen-fluorid. Anbefalte kriterier for fluoriders virkning på vegetasjon er overskredet i et område rundt verket på 25 km2, inkludert bedriftsområdet og områder over sjø påvirket landareal utenom bedriftsområdet er 11,5 km2. Takutslipp fra produksjonshallene utgjør 95 % av konsentrasjonsbidraget i området med overskridelse.
2016
Science Press
2019
2023