Steven H. Cadle's research while affiliated with General Motors Company and other places

... Research during the 1970s has contributed many Gaussian theory based line source models. For example AIRPOLfour models developed by Carpenter and Clemana (1975); GM model developed by Chock (1977aChock ( , 1977bChock ( , 1978) based on sulfate dispersion study; and EPA-HIWAY-1 by Zimmerman and Thompson (1975), a useful model to estimate the CO concentration from the vehicular exhausts. Aron and Aron (1978) forecast daily maximum CO concentrations throughout the Los Angeles (California) area using deterministic models and discovered that the most important variables were the preceding day's CO concentration, pressure differences between nearby stations, receptor height, surface temperature, day of the week, length of daylight, potential solar radiation, and the height of the inversion base. ...

... Also, chasing approach captures a "snapshot" of the emissions of target vehicle under its real world driving conditions. While vehicle emission is a function of loading, speed, road conditions and fuel quality etc (Cadle et al., 1999), it is important to pre-define the scope of measurement in order to apply the chasing approach to investigate fleet emission characteristics and make comparison on a consistent basis. The present study focused on the fleet emissions on their highway driving mode with typical cruise speed of 60 kmph to exclude the uncertainties due to different driving conditions. ...

... Whereas trace metals like Cu, Ni, Co, Fe and Pb showed short-range in concentrations suggesting a more homogenous distribution among different size fractions. The high variations observed in Zn reflects anthropogenic contributions from vehicle wear, oil leakage, tire wear and from the contaminated surrounding soil (Lagerwerff and Specht 1970;Pierson and Brachaczek 1983;Cadle et al. (Wigington et al. 1983). For soil, similar trends for Ni, Cu and Zn were observed. ...

... Field and wind tunnel measurements of aerosol deposition clearly show much lower deposition velocities for small aerosols than for large aerosols, especially at low windspeeds (Chamberlain 1975, Thorne et al. 1982, Voldner et al. 1986). Cadle and Groblicki (1983) found that, despite similar volumes of water, dew on the top of a horizontal plastic surface collected five times as much Ci and nine times as much Ca 2+ as dew on the bottom surface, a result consistent with dry deposition dominated by fallout. The presence of ions (K + , Ca 2 + , Mg 2 + , Na + ) that lacked any gaseous sources in the dews formed on Teflon Indicated that these ions entered dews as sedimenting aerosols. ...

... These vehicles have emissions from 10 to 1000 times higher than the average of those from all vehicles (23). Approximately 15% of vehicle driving time is in the off-cycle mode (24). The impact of off-cycle operation on emissions is difficult to determine since not all vehicles experience this off-cycle driving, and 15% of the time does not correspond to 15% of the lifetime driving distance. ...

... In recent years, there has been considerable research on vehicular emissions and fumes (Lilley, 2000;Marshall et al, 2003;Ababio, 2003;Cadle et al, 2000Cadle et al, , 2001Cadle et al, , 2003Cadle et al, and 2004. Pollution from motor vehicles has become an issue simply because of the steady increase both in the number of vehicles in use and the distances travelled by each vehicle. ...

... For the entire study, the average mass ratio of NO3 − /SO4 2− is 1.28, much higher than that observed in other regions of China [26,30]. In addition, the NO3 − /SO4 2− mass ratios monitored in the same sampling site as this study in 2000 and 2002 are 0.58 and 0.78, respectively [31,32]. The significant increase of NO3 − /SO4 2− mass ratio in Beijing from 2000 to 2013 reveals that the relative importance of motor vehicles to PM pollution may rise largely during the past years. ...

... In examining the potential health effects of modern, direct-injection engine PM, it is useful to examine historical PM emissions as a basis for comparison. A number of studies have put forward data that show the PM emissions of vehicles during the 1980s and 1990s (5,6), however, the PM emissions from earlier vehicles in proper operating condition are a relative unknown. This is due largely to the lack of advanced instrumentation during the period. ...

... This includes both attribution of health effects as well as assessments of exhaust composition. Only a handful of studies have characterized the chemical composition of GEE in detail (e.g., Fraser et al., 1998;Knapp et al, 2003;Phuleria et al., 2006;Robert et al., 2007;Schauer et al., 2002Schauer et al., , 2008Zielinska et al., 2004), but there have been many studies that have characterized DEE (reviewed in Lloyd & Cackette, 2001). Many of the chemical components of interest in DEE are also present in GEE. ...

... Stoddard (1994) suggests that 40% of annual inputs of N in boreal regions occur as dry deposition. Winter seasonal NO À 3 dry deposition near the boreal forest comprised 17% of total deposition in northern Michigan, USA (Cadle and Dasch, 1987) and 5% at Turkey Copyright # 1999 (Semkin and Jeries, 1988). Sirois and Vet (1988) modelled a 27% seasonal dry deposition contribution for the same region as these two observational studies. ...