Re: Microsoft Streets And Trips 2013 Crack Only Nitro
Raingarda Krzynowek
Several recent studies have reported on the changes in thecomposition of diesel exhaust linked to new technology.Emission trends in fluoranthene, pyrene,benzo[a]pyrene,benzo[e]pyrene and 1-nitropyrene withchanging engine technology are shown in Fig. 1.6 as a fraction of theemissions from pre-1999 technology. All compounds showed amarked downward trend. Emissions from the 2000 and 2004transitional technology engines represented only a fraction(maximum, 40%) of those from the traditional technologyengines, and a further decrease occurred with theintroduction of new technology engines fitted with catalysedDPFs.
Zielinska etal. (2004) also measured the levels ofnine nitro-PAHs: 1-nitronaphthalene, 2-methyl-nitronaphthalene,methyl-nitronaphthalene, 9-nitroanthracene, 3-nitrofluoranthene,1-nitropyrene, 7-nitrobenzo[a]anthracene,6-nitrochrysene, and 6-nitrobenz[a]pyrene. Thesum of their emission rates, excluding 2-methyl-nitronaphthaleneand methyl-nitronaphthalene, was calculated by the WorkingGroup. [These two species were excluded to report only those incommon with the study by EPA (2008) described below.] Total emission rates ofthese nitro-PAHs were close to or below the limit of detectionfrom NG [not reported] and were low from the other gasolinevehicles: [0.11], [0.27], [1.29] and [1.02] μg/mile from G30, G,BG and WG, respectively, and were not significantly influencedby temperature.
For gasoline vehicles, the current light-duty PM emissionstandards in Europe and in the USA are 78 and 62mg/kgfuel, respectively. The estimate ofemissions from the current in-use gasoline fleet (CARB, 2011) is 25mg/kgfuel and the emissions from the variousfleets tested ranged from 1 to 23 mg/kgfuel. Theaverage value of PM emissions from the three GDI vehiclestested by Anderssonet al. (2007) was 130mg/kgfuel, but engines have evolved rapidly,and the average level of emissions from nine GDI vehicletested 5 years later by Zhang & McMahon (2012) was 36mg/kgfuel. Levels of PAHs and 1-nitropyrenewere also converted into nanograms per kilogram of fuel. Thelevel of high-molecular-weight particle-bound PAHs rangedfrom 2 to 480 and from 2400 to 17 000 ng/kgfuelfor DPF-fitted diesel and PFI gasoline engines,respectively. Emissions of 1-nitropyrene ranged from 1 to350 ng/kgfuel for DPF-fitted diesel engines, andthose for the only gasoline engine measured were 2ng/kgfuel.
The conversion of HGVs to diesel engines began in the 1950sand from the 1960s and 1970s predominantly diesel-poweredheavy-duty vehicles were sold. In contrast to Europe, whereabout one-third of all new passenger cars have dieselengines, only very few new passenger cars or taxis in theUSA are diesel-fuelled (Lloyd & Cackette, 2001).Workers in occupations that involve the driving, maintenanceand unloading of diesel HGVs and, to a lesser extent, dieselcars can be exposed to diesel exhaust. Table 1.14summarizes the reported levels of exposure to EC, carbonmonoxide, nitric oxide and nitrogen dioxide for workersexposed to diesel engine exhaust from on-road vehicles, byagent and by activity.
Janssen etal. (2001) reported a study of aircontaminants from traffic in 24 schools in the Netherlandsas a function of traffic density, distance from a heavilytravelled motorway and percentage of time the school wasdownwind from the motorway. They found that traffic countsfor HGVs, but not cars, were related to black carbon. Bothindoor and outdoor concentrations of black carbon declinedwith increasing distance from the road, and the averageconcentration was about 20% higher indoors compared withoutdoors, possibly because indoor samples were onlycollected when schools were open during the day, whereasoutdoor samples were collected around the clock, includinglow ambient concentrations at night and on weekends. Thepercentage of time that the school was downwind from themotorway significantly increased the levels of black carbon,nitrogen dioxide and benzene indoors, but not those ofbenzene and PM2.5 outdoors. The level of nitrogendioxide showed no gradient with distance.
Time spent in vehicles can contribute a large proportion oftotal exposure to vehicle exhaust (Fruin et al.,2004, 2008). Fruin et al. (2008) measuredon-road exposures in Los Angeles, CA, USA, extensively. Anelectric car outfitted with sampling devices was used tominimize the contributions of the sampling platform to theexposures (Westerdahlet al., 2005; Fruin etal., 2008). They used real-timemonitors for PM2.5, particle counts by size,including ultrafine particles, nitric oxide, nitrogendioxide, black carbon, particle-bound PAHs, carbon monoxideand carbon dioxide. Sampling frequencies ranged from2 seconds up to 1 minute. They drove on two routes: afreeway route and an arterial street route. While driving,they videotaped the traffic in and then performed analysesto determine the type of vehicle followed for each 5-minuteinterval, vehicle speed, acceleration, road type, trafficdensity, fraction of HGVs among all vehicles and the numberof leading and surrounding vehicles during acceleration.In-cabin exposures on Los Angeles freeways were dominated bydiesel truck emissions, including ultrafine particles,nitric oxide, black carbon and PAHs bound to ultrafineparticles. Table 1.25 summarizes the median concentrationsand interquartile ranges for each of the contaminants indifferent road and traffic settings. In dense traffic on thefreeways, the time from emission to entering the passengercompartments of nearby vehicles was very short (Fruin etal., 2008). Exposure concentrationswere proportional to the density of HGVs, but not to thetotal volume of vehicles. Automobiles did not contributesignificantly to the variability of freeway pollutants.However, on arterial streets with heavy traffic with mixedvehicles and frequent traffic lights, the emissions weredominated by those from groups of cars acceleratingpowerfully after having stopped at the lights. Powerfulacceleration can overload the catalytic exhaust pollutioncontrol, allowing considerably more emissions (Fruin etal., 2008). The close grouping andlimited ventilation of the area can lead to briefaccumulation of the emissions. High-speed acceleration doesnot produce the same accumulation because vehicles are morewidely spread out and surrounded by high-velocity air flows.Table 1.26 gives the explanatory strength(R2) for the predictive variables and each ofthe contaminant measures.
Studies in the Netherlands have shown that black carbon is abetter marker of personal or indoor versus outdoor exposuresthan nitric oxide, nitrogen dioxide or nitrogen oxides(Wichmannet al., 2005; Van Roosbroecket al., 2006). In addition,the outdoor exposures to black carbon close to busy urbanstreets compared with those near quiet urban streets were29% higher for adults (n = 16 days;P
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