• polyaromatic hydrocarbons
  • Surface decontamination efficacy determination of DeconGelTM 1101 and 1102 on aluminum, stainless steel, and concrete surfaces contaminated with Crude Oil (polyaromatic hydrocarbons fraction) was performed with LC/MS (Liquid Chromatography/Mass Spectrometry) according to Environmental Protection Agency (EPA) SW-846 Methods: 3500C (sampling), 8321B (analysis), and 1654A (Analysis of PAH Content of Oil). (environmental-expert.com)
  • soot
  • Air sampled from the breathing zone of chimney sweeps during "dirty work" and soot samples were analysed for polycyclic aromatic hydrocarbons (PAH). (bmj.com)
  • Presence of such smoke, soot, and/or brown oily deposits during a fire indicates a possible hazardous situation, as the atmosphere may be saturated with combustible pyrolysis products with concentration above the upper flammability limit, and sudden inrush of air can cause flashover or backdraft. (wikipedia.org)
  • Effect of CF3I Compared to CF3Br on OH and Soot Concentrations in Co-Flowing Propane/Air Diffusion Flames. (nist.gov)
  • In the present study, OH and soot concentrations have been measured using fluorescence imaging and laser-induced incandescence methods, respectively, in a co-flowing, axisymmetric, atmospheric-pressure propane/air diffusion flame inhibited by CF3Br and CF3I. (nist.gov)
  • Overall, the two suppressants behave similarly when added to both the air and fuel streams, with the most notable exception being the greaer enhancement of soot production for CF3Br addition at subextinction concentrations. (nist.gov)
  • CF3I is found to slightly superior to CF3Br under our experimental conditions in terms of requiring smaller mole fraction concentrations at extinction and producing less within-flame soot. (nist.gov)
  • Soot /sʊt/ is a mass of impure carbon particles resulting from the incomplete combustion of hydrocarbons. (wikipedia.org)
  • Soot in very low concentrations is capable of darkening surfaces or making particle agglomerates, such as those from ventilation systems, appear black. (wikipedia.org)
  • aromatics can form soot both by this route and also by a more direct pathway involving ring condensation or polymerization reactions building on the existing aromatic structure. (wikipedia.org)
  • methane
  • As the Sun's ultraviolet output decreases, the haze in Titan's upper atmosphere will be depleted, lessening the anti-greenhouse effect on its surface and enabling the greenhouse effect created by atmospheric methane to play a far greater role. (wikipedia.org)
  • The presence of a significant atmosphere was first suspected by Spanish astronomer Josep Comas i Solà, who observed distinct limb darkening on Titan in 1903, and confirmed by Gerard P. Kuiper in 1944 using a spectroscopic technique that yielded an estimate of an atmospheric partial pressure of methane of the order of 100 millibars (10 kPa). (wikipedia.org)
  • The hydrocarbons are thought to form in Titan's upper atmosphere in reactions resulting from the breakup of methane by the Sun's ultraviolet light, producing a thick orange smog. (wikipedia.org)
  • Energy from the Sun should have converted all traces of methane in Titan's atmosphere into more complex hydrocarbons within 50 million years - a short time compared to the age of the Solar System. (wikipedia.org)
  • contaminants
  • Mussel Watch monitors the concentration of contaminants in bivalves (mussels and oysters) and sediments in the coastal waters of the U.S., including the Great Lakes, to monitor bivalve health and by extension the health of their local and regional environment. (wikipedia.org)
  • deposition
  • These predicted levels suggest that N205 may be important as an atmospheric constituent, both in nitration reactions of PAH and in the nighttime formation of nitric acid, a major component of acidic deposition. (ca.gov)
  • toxic
  • The ERL indicates the concentration below which toxic effects are scarcely observed or predicted: the ERM indicates that above which effects are generally or always observed. (wikipedia.org)
  • meteorological
  • For analysis of atmospheric processes in the urban environment, the microscale meteorological and dispersion model M2UE is suggested, which takes into account a complex character of aerodynamics in non-uniform urban relief. (environmental-expert.com)
  • Meteorological conditions, such as temperature, wind speed and humidity, strongly affect PAH concentrations at all sampling sites. (biomedsearch.com)
  • quantities
  • The atmospheric pressure photoionization source, PhotoSpray ion source (Robb, Covey and Bruins1) uses photons to ionize large quantities of a dopant molecule added along with the vaporized mobile phase. (bio-medicine.org)
  • Crude
  • Oil spills provided perfect opportunities for scientists to examine the in situ effects of crude oil exposure to marine ecosystems, and collaborative efforts between the National Oceanic and Atmospheric Administration (NOAA) and the United States Coast Guard resulted in improved response efforts and detailed research on oil pollution's effects. (wikipedia.org)
  • soil
  • Future UK PCB air concentrations will presumably therefore be influenced (controlled) by the rate of desorption and outgassing, as soil and air concentrations move towards a condition of equilibrium partitioning. (lancs.ac.uk)
  • Short-term air-soil exchange, such as during soil drying in the laboratory, can lead to contamination of samples which contain low concentrations of PCBs and loss from samples which contain high concentrations. (lancs.ac.uk)
  • National Oceanic and At
  • The National Oceanic and Atmospheric Administration (NOAA) National Status and Trends (NS&T) Mussel Watch Program is a contaminant monitoring program that started in 1986. (wikipedia.org)
  • The numerical values are incorporated in sediment quality guidelines (SQGs) that were developed by Long and Morgan for the National Oceanic and Atmospheric Administration (NOAA) National Status & Trends program as informal tools to evaluate whether a concentration of a contaminant in sediment might have toxicological effects. (wikipedia.org)
  • Following here is a summary of how the ERL/ERM guidelines are used by the National Oceanic and Atmospheric Administration, United States Geological Survey (USGS), and the United States Environmental Protection Agency (EPA). (wikipedia.org)
  • different
  • The difference between the sooting tendencies of aliphatics and aromatics is thought to result mainly from the different routes of formation. (wikipedia.org)
  • respectively
  • The air concentrations of BaP were 0.36, 0.83, and 0.82 micrograms/m3 respectively. (bmj.com)
  • 2-Nitrofluoranthene was the most abundant nitro-PAH, accounting for 54% of the total nitro-PAH concentration, followed by 9-nitroanthracene, 3-nitrophenanthrene and 7-nitrobenz(a)anthracene, about 15%, 16% and 10%, respectively. (environmental-expert.com)
  • Marine
  • An oil spill is the release of a liquid petroleum hydrocarbon into the environment, especially the marine ecosystem, due to human activity, and is a form of pollution. (wikipedia.org)
  • basis
  • The time weighted, shift mean concentrations of 0.02 to 0.21 micrograms/m3 benzo(a)pyrene obtained on 11 days form the basis for the industrial medical estimation of risk. (bmj.com)
  • pressure
  • The atmospheric pressure photoionization source PhotoSp. (bio-medicine.org)
  • Atmospheric pressure photoionization is a new technique that uses the energy of photons to generate ions from the vaporized eluent of an LC. (bio-medicine.org)
  • At atmospheric pressure it has no melting point as its triple point is at 10.8 ± 0.2 MPa and 4,600 ± 300 K (~4,330 °C or 7,820 °F), so it sublimes at about 3,900 K. Graphite is much more reactive than diamond at standard conditions, despite being more thermodynamically stable, as its delocalised pi system is much more vulnerable to attack. (wikipedia.org)
  • range
  • After ranking, both the 10th and 50th percentile concentrations are determined over the range of endpoint concentrations. (wikipedia.org)
  • The USGS has also integrated ERL and ERM values into an Alert Range Table, a table that provides ranges of contaminant concentrations that predict the likelihood of adverse effects occurring in benthic organisms for the Lake Pontchartrain Basin in Louisiana. (wikipedia.org)
  • less
  • therefore in this molecule the outer rings have greater aromatic character whereas the central ring is less aromatic and therefore more reactive. (wikipedia.org)