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- Dahl, Andreas, et al.
(författare)
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Traffic-generated emissions of ultrafine particles from pavement-tire interface
- 2006
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Ingår i: Atmospheric Environment. - : Elsevier. - 1352-2310 .- 1873-2844. ; 40:7, s. 1314-1323
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Tidskriftsartikel (refereegranskat)abstract
- In a road simulator study, a significant source of sub-micrometer fine particles produced by the road-tire interface was observed. Since the particle size distribution and source strength is dependent on the type of tire used, it is likely that these particles largely originate from the tires, and not the road pavement. The particles consisted most likely of mineral oils from the softening filler and fragments of the carbon-reinforcing filler material (soot agglomerates). This identification was based on transmission electron microscopy studies of collected ultrafine wear particles and on-line thermal treatment using a thermodesorber. The mean particle number diameters were between 15-50 nm, similar to those found in light duty vehicle (LDV) tail-pipe exhaust. A simple box model approach was used to estimate emission factors in the size interval 15-700 nm. The emission factors increased with increasing vehicle speed, and varied between 3.7 x 10(11) and 3.2 x 10(12) particles vehicle(-1) km(-1) at speeds of 50 and 70 km h(-1). This corresponds to between 0.1-1% of tail-pipe emissions in real-world emission studies at similar speeds from a fleet of LDV with 95% gasoline and 5% diesel-fueled cars. The emission factors for particles originating from the road-tire interface were, however, similar in magnitude to particle number emission factors from liquefied petroleum gas-powered vehicles derived in test bench studies in Australia 2005. Thus the road-tire interface may be a significant contributor to particle emissions from ultraclean vehicles. (c) 2005 Elsevier Ltd. All rights reserved.
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- Gustafsson, Mats, et al.
(författare)
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Factors influencing PM10 emissions from road pavement wear
- 2009
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Ingår i: Atmospheric Environment. - : Elsevier BV. - 1352-2310. ; 43:31, s. 4699-4702
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Konferensbidrag (refereegranskat)abstract
- Accelerated pavement wear is one of the major environmental disadvantages of studded tyres in northern regions and results in increased levels of PM10. Measurements of PM10 in a road simulator hall have been used to study the influence of pavement properties, tyre type and vehicle speed on pavement wear. The test set-up included three different pavements (one granite and two quartzite with different aggregate sizes), three different tyre types (studded, non-studded, and summer tyres) and different speeds (30-70 km h(-1)). The results show that the granite pavement was more prone to PM10 production compared to the quartzite pavements. Studded winter tyres yield tens of times higher PM10 concentrations compared to non-studded winter tyres. Wear from summer tyres was negligible in comparison. It was also shown that wear is strongly dependent on speed; every 10 km h(-1) increase yielded an increase of the PM10 concentration of 680 mu g m(-3) in one of the simulator experiments. (C) 2008 Elsevier Ltd. All rights reserved.
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- Gustafsson, Mats, et al.
(författare)
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Inandningsbara partiklar från dubbdäcksslitage av vägbana : egenskaper och inflammatoriska effekter i mänskliga luftvägsceller. utdrag ur WearTox-projektet (VTI rapport 520)
- 2005
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The aims of this project have been to describe PM10 from studded tyre wear and to study their inflammatory effects in human airway cells. The VTI circular road simulator has been used to generate "clean" wear particles from two different pavements; asphalt concrete (ABT) and stone mastic asphalt (ABS), with granite respectively quartzite as the main stone materials. The advantage of using the road simulator is that the contribution from other sources can be minimised. During the project time, the project was expanded also to study particle generation by non-studded winter tyres (friction tyres) and two kinds of winter sanding agents, namely washed crushed stone and unwashed natural sand in combination with both studded and friction tyres. Most of these parts of the project are presented in VTI report 520. The results show that pavement wear by studded tyres generates about 40-50 times as much PM10 as that by friction tyres, but also that the ABT pavement generates several times more PM10 than the ABS pavement. The size distribution within PM10 has a maximum around 3-4 ?m and more than 95 % of the mass is larger than 1 ?m. PM10 is totally dominated by fresh stone material. A fraction of very small particles, with a number concentration peak at around 30-40 nm, was also discovered. Their origin is unknown, but since the number distribution shifted depending on which tyre type was used, a possible origin is the tyres. In the cell studies the inflammation potential of the wear particles was compared with PM10 from Hornsgatan in Stockholm and PM10 from a Stockholm subway station. Later on in the project, diesel particles were made available for comparison. The cell study results show that PM10 from the ABT pavement is at least as inflammatory as diesel particles and more inflammatory than PM10 from the subway. The PM10 from Hornsgatan generally had the highest potential, but PM10 from the ABT pavement was often in parity. This despite the fact that the Hornsgatan PM10 were the only particle sample where endotoxin could be detected. Endotoxin causes an additive effect in studies of inflammation potential. PM10 from the ABS pavement generally had a lower potential than PM10 from the ABT pavement.
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- Gustafsson, Mats, et al.
(författare)
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Inandningsbara partiklar från interaktion mellan däck, vägbana och friktionsmaterial : slutrapport av WearTox-projektet
- 2005
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The aims of this project have been to describe PM10 from studded tyre wear and to study their inflammatory effects in human airway cells. The VTI circular road simulator has been used to generate "clean" wear particles from two different pavements; asphalt concrete (ABT) and stone mastic asphalt (ABS), with granite respectively quartzite as the main stone materials. The advantage of using the road simulator is that the contribution from other sources can be minimised. During the project time, the project was expanded also to study particle generation by non-studded winter tyres (friction tyres) and two kinds of winter sanding agents, namely washed crushed stone and unwashed natural sand in combination with both studded and friction tyres. The results show that pavement wear by studded tyres generates about 40-50 times as much PM10 as that by friction tyres, but also that the ABT pavement generates several times more PM10 than the ABS pavement. The size distribution within PM10 has a maximum around 3-4 ?m and more than 95 % of the mass is larger than 1 ?m. PM10 is totally dominated by fresh stone material. A fraction of very small particles, with a number concentration peak at around 30-40 nm, was also discovered. Their origin is unknown, but since the number distribution shifted depending on which tyre type was used, a possible origin is the tyres. In the experiments using sanding material, the unwashed natural sand caused the highest PM10 concentrations. Friction tyres on natural sand caused higher concentrations than studded tyres on washed crushed stone. Studded tyres generated more PM10 than friction tyres but the difference was not as large as when no sanding material was used. In the cell studies the inflammation potential of the wear particles was compared with PM10 from Hornsgatan in Stockholm and PM10 from a Stockholm subway station. Later on in the project, diesel particles were made available for comparison. The cell study results show that PM10 from the ABT pavement is at least as inflammatory as diesel particles and more inflammatory than PM10 from the subway. The PM10 from Hornsgatan generally had the highest potential, but PM10 from the ABT pavement was often in parity. This despite the fact that the Hornsgatan PM10 were the only particle sample where endotoxin could be detected. Endotoxin causes an additive effect in studies of inflammation potential. PM10 from the ABS pavement generally had a lower potential than PM10 from the ABT pavement.
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