Traffic - tunnel

Rogak, S. N., S. I. Green, and U. Pott, Use of Tracer Gas for Direct Calibration of Emission-Factor Measurements in a Traffic Tunnel, J. Air Waste Manage. Assoc., 48, 545-552 (1998a). 

Over the past two decades, the ambient air levels of PAHs in a number of major cities have been characterized. Although data from studies in different areas cannot be used to indicate definitive temporal trends in PAH air levels, a comparison of the results of these studies yields no strong suggestion that the ambient air levels of PAHs may be decreasing, except in traffic tunnels. 

Atmospheric PAH concentrations have been found to be significantly elevated in areas of enclosed traffic tunnels. In a 1985-86 study in the Baltimore Harbor Tunnel the average concentrations of particle-phase PAHs ranged from 2.9 ng/m for anthracene to 27 ng/m for pyrene (Benner and Gordon. 1989). These values are up to an order of magnitude lower than those obtained in 1975 by... 

The measurements on the source profiles of traffic emission were carried out in a traffic tunnel (Kiesberg Tunnel), a downtown street intersection and during drives in the city centre of Wuppertal and on the freeways. Profiles of each of these measurements have been... 

NMVOC profiles for traffic emissions were measured in a traffic tunnel, a down-town intersection, during city and freeway drives. All the profiles obtained showed very similar mass distributions of the measured compounds. Hence, one single averaged traffic emission profile representing all traffic conditions was created. 

Li et al. (2001) measured the PAH emission from incineration of plastic wastes and detected several individual PAHs in raw wastes, flue gas and bottom ash. The PAHs, however, were entirely destroyed when incinerated in excess amounts of air supply. Wich-mann et al. (1995) quantitatively measured the release of PAHs and the polychlorinated dibenzo-p-dioxins in a case study involving vehicle fires in traffic tunnels. 

Wichmann, H., W. Lorenz, and M. Bahadir. 1995. Release of PCDD/F and PAH during vehicle fires in traffic tunnels. Chemosphere 31(2) 2755-66. 

Traffic/tunnels/car parks City traffic control and management air quality monitoring in tunnels or underground parking garages CO, O3, NO, SO, CH, LPG... 

An interesting problem solved by operations research methods is that of the flow of traffic through the New York tunnels. The presence of toll booths causes congestion of traffic at the entrances and exits of tunnels. Economical operation of the toll booths necessitates that not all booths be open at all times. By studying the statistics of the traffic, a schedule was developed indicating the number of booths to be operated at different times of the day. In this manner congestion was alleviated, and the frequency of traffic jams was reduced considerably.8... 

Traffic in a Los Angeles Roadway Tunnel, Environ. Sci. Technol., 32, 2051-2060 (1998). 

Switzerland presently follows the traffic policy of shifting transport by heavy trucks on roads to railway transport. Towards this goal, the capacity of the main traffic axis (N S) is now being greatly expanded by the AlpTransit project. The key elements of this project are the two railway base tunnels the Lotschberg tunnel in the west and the Gotthard tunnel in the east (see Fig. 7). The rock overburden can reach 2.5 km, and the lengths are considerable 57 km... 

The primary objects of investigation in both TSL and TSC experiments are nonra-diative transitions between the ground level and trap and the conduction band and/or valence band. In a case when two different impurities—a donor and an acceptor—are close enough that their functions overlap, tunneling processes may take place from an excited level of the donor to the acceptor. In this case, the excited level can be occupied from the ground state via a nonradiative transition. In a case when recombination traffic proceeds via tunneling between donor-acceptor pairs, no TSC will be observed. 

Materials for roads Tunnel wall, soundproofed wall, traffic signs and reflectors... 

As mentioned in the introduction, the concentration of NO in Japan has remained almost constant for the last 10 years and often exceeds the air quality standard set for nitrogen dioxide (N02), particularly along heavy traffic roads in densely populated areas. To counter this situation, the development of a new technology for removing NO at sub-ppm level from air cf traffic roads, tunnels or other environmental emission sources is essential. 

Stembeck J, Sjodin A, Andreasson K (2002) Metal emissions from road traffic and the influence of resuspension—results from two tunnel studies. Atmos Environ 36 4735 1744... 

Underground tunnel construction joints and sections Attaching metal studs in concrete Bonding pancake lighting systems on airport runways Bonding traffic markers on roadways and road dividers... 

Bridge, culvert, dam, road, parking area, storage area, railway track, railway traffic control equipment, subway or tunnel, electrical generating equipment, pipeline other than gas and oil building... 

Evaluation of the content of PGMs in airborne particles and dusts is important because of the possibility of their inhalation and accumulation in human lungs. Nanoparticles from autocatalysts can be transported into various parts of the environment (waters, plants, soils, and sediments) and transformed into more bioavailable species. There are data on the higher solubility of platinum from tunnel dusts than from inorganic species emitted from converters [30]. Distribution and accumulation of metals depend on traffic density, distance from the road, and meteorological conditions (wind, rain). The age of an autocatalyst and speed conditions directly affect the amount of nanoparticles released from catalytic... 

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