1. |
- Abbasi, Saeed, et al.
(författare)
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A pin-on-disc study of the rate of airborne wear particle emissions from railway braking materials
- 2012
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Ingår i: Wear. - UK : Elsevier. - 0043-1648 .- 1873-2577. ; 284, s. 18-29
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Tidskriftsartikel (refereegranskat)abstract
- The current study investigates the characteristics of particles generated from the wear of braking materials, and provides an applicable index for measuring and comparing wear particle emissions. A pin-on-disc tribometer equipped with particle measurement instruments was used. The number concentration, size, morphology, and mass concentration of generated particles were investigated and reported for particles 10 nm-32 mu m in diameter. The particles were also collected on filters and investigated using EDS and SEM. The effects of wear mechanisms on particle morphology and changes in particle concentration are discussed. A new index, the airborne wear particle emission rate (AWPER), is suggested that could be used in legislation to control non-exhaust emissions from transport modes, particularly rail transport.
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2. |
- Abbasi, Saeed, 1973-, et al.
(författare)
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A field test study of airborne wear particles from a running regional train
- 2012
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Ingår i: IMechE, Part F: Journal of Rail and Rapid Transit. - UK : Sage Publications. - 0954-4097 .- 2041-3017. ; 226:1, s. 95-109
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Tidskriftsartikel (refereegranskat)abstract
- Inhalable airborne particles have inverse health affect. In railways, mechanical brakes, the wheel–rail contact, current collectors, ballast, sleepers, and masonry structures yield particulate matter. Field tests examined a Swedish track using a train instrumented with particle measurement devices, brake pad temperature sensors, and speed and brake sensors. The main objective of this field test was to study the characteristics of particles generated from disc brakes on a running train with an on-board measuring set-up.Two airborne particle sampling points were designated, one near a pad–rotor disc brake contact and a second under the frame, not near a mechanical brake or the wheel–rail contact; the numbers and size distributions of the particles detected were registered and evaluated under various conditions (e.g. activating/deactivating electrical brakes or negotiating curves). During braking, three speed/temperature-dependent particle peaks were identified in the fine region, representing particles 280 nm, 350 nm, and 600 nm in diameter. In the coarse region, a peak was discerned for particles 3–6 μm in diameter. Effects of brake pad temperature on particle size distribution were also investigated. Results indicate that the 280 nm peak increased with increasing temperature, and that electrical braking significantly reduced airborne particle numbers. FESEM images captured particles sizing down to 50 nm. The ICP-MS results indicated that Fe, Cu, Zn, Al, Ca, and Mg were the main elements constituting the particles.
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4. |
- Abbasi, Saeed, et al.
(författare)
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Particle emissions from rail traffic : a literature review
- 2013
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Ingår i: Critical reviews in environmental science and technology. - USA : Taylor & Francis. - 1064-3389 .- 1547-6537. ; 43:23, s. 2211-2244
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Forskningsöversikt (refereegranskat)abstract
- Particle emissions are a drawback of rail transport. This work is a comprehensive presentation of recent research into particle emissions from rail vehicles. Both exhaust and non-exhaust particle emissions are considered when examining particle characteristics such as PM10, and PM2.5 concentration levels, size, morphology, composition, as well as adverse health effects, current legislation, and available and proposed solutions for reducing such emissions. High concentration levels in enclosed rail traffic environments are reported and some toxic effects of the particles. We find that only a few limited studies have examined the adverse health effects of non-exhaust particle emissions and that no relevant legislation exists. Thus further research in this area is warranted.
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5. |
- Alami, Jones, et al.
(författare)
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High-power impulse magnetron sputtering of Ti-Si-C thin films from a Ti3SiC2 compound target
- 2006
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Ingår i: Thin Solid Films. - : Institutionen för fysik, kemi och biologi. - 0040-6090 .- 1879-2731. ; 515:4, s. 1731-1736
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Tidskriftsartikel (refereegranskat)abstract
- We have deposited Ti-Si-C thin films using high-power impulse magnetron sputtering (HIPIMS) from a Ti3SiC2 compound target. The as-deposited films were composite materials with TiC as the main crystalline constituent. X-ray diffraction and photoelectron spectroscopy indicated that they also contained amorphous SiC, and for films deposited on inclined substrates, crystalline Ti5Si3Cx. The film morphology was dense and flat, while films deposited with dc magnetron sputtering under comparable conditions were rough and porous. Due to the high degree of ionization of the sputtered species obtained in HIPIMS, it is possible to control the film composition, in particular the C content, by tuning the substrate inclination angle, the Ar process pressure, and the bias voltage.
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6. |
- Berndt, Sonja I., et al.
(författare)
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Genome-wide meta-analysis identifies 11 new loci for anthropometric traits and provides insights into genetic architecture
- 2013
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Ingår i: Nature Genetics. - : Springer Science and Business Media LLC. - 1061-4036 .- 1546-1718. ; 45:5, s. 501-U69
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Tidskriftsartikel (refereegranskat)abstract
- Approaches exploiting trait distribution extremes may be used to identify loci associated with common traits, but it is unknown whether these loci are generalizable to the broader population. In a genome-wide search for loci associated with the upper versus the lower 5th percentiles of body mass index, height and waist-to-hip ratio, as well as clinical classes of obesity, including up to 263,407 individuals of European ancestry, we identified 4 new loci (IGFBP4, H6PD, RSRC1 and PPP2R2A) influencing height detected in the distribution tails and 7 new loci (HNF4G, RPTOR, GNAT2, MRPS33P4, ADCY9, HS6ST3 and ZZZ3) for clinical classes of obesity. Further, we find a large overlap in genetic structure and the distribution of variants between traits based on extremes and the general population and little etiological heterogeneity between obesity subgroups.
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7. |
- Bonow, Madeleine A
(författare)
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Gård, gräns, giftermål : Familjestrategiers betydelse för markens och landskapets utformning i Norra Åsarps socken, Västergötland ca 1640-1880
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation deals with property rights and the implications of these for people, landscape and settlement in Norra Åsarp Parish in the province of Västergötland.The overarching aim of the thesis is to investigate systems of social rules and how these influence the structure of settlement and land use/ownership. The central question concerns how the peasant family reproduced and maintained social and physical boundaries and if there are any relationships between territoriality and social class.The analysis has led us to the unexpected result that there was a surprising degree of continuity concerning the individual field strips. This is remarkable since the social system otherwise showed a rather rapid rotation in farm occupancy. The intriguing question here is why it was like this in this area? Why were there no changes in the allotment system? To solve this question special attention is given to reproduction and farm practice at the individual level. The social structure was primarily characterised by families who farmed on a small scale. The farms belonging to a larger kinship group circulated between the relatives and were farmed by the most suitable couple available. The marital strategy made group identity well connected and the family identity become strong. The social system was to some extent readable in the landscape: the family tree was more or less written on the ground. This investigation may provide an explanation to why there were no changes in the allotment system.The basis of the taxation in Norra Åsarp may have been the allotment system itself and this may explain why nothing happens on the ground: land had to stay fixed and tied to specific homesteads, otherwise it would be hard to calculate the rights and duties of the farm.
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8. |
- Jansson, Anna, et al.
(författare)
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Magnetron sputtering of the high entropy alloy CoCrFeMnNi on 316L : Influence of substrate grain orientations
- 2023
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Ingår i: Surface & Coatings Technology. - : Elsevier. - 0257-8972 .- 1879-3347. ; 466
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Tidskriftsartikel (refereegranskat)abstract
- This study explores the influence of a 316L stainless steel substrate on the magnetron sputtering of the Cantor alloy CoCrFeMnNi at different substrate bias. The study was carried out on a polycrystalline 316L substrate where the growth behavior of the coating could be investigated on grains with different orientations. By combining electron backscatter diffraction (EBSD) before and after deposition and characterization of the same area, it was possible to determine growth behaviour and surface morphologies on individual substrate grains. No strong influence of the substrate was observed at a floating bias. At a bias of -100V, however, the coating was strongly influenced by the orientation of the individual substrate grains. Epitaxial coating grains with a smooth surface were observed on the [102]-oriented grains while a more columnar growth was observed on [111]-oriented grains. Furthermore, a small difference in growth rate was observed on different substrate orientations. The growth behaviour could be related to differences in surface energies and diffusion rates on different surface orientations.
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9. |
- Marklund, Matti, et al.
(författare)
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Biomarkers of Dietary Omega-6 Fatty Acids and Incident Cardiovascular Disease and Mortality : An Individual-Level Pooled Analysis of 30 Cohort Studies
- 2019
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Ingår i: Circulation. - : American Heart Association. - 0009-7322 .- 1524-4539. ; 139:21, s. 2422-2436
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Tidskriftsartikel (refereegranskat)abstract
- Background:Global dietary recommendations for and cardiovascular effects of linoleic acid, the major dietary omega-6 fatty acid, and its major metabolite, arachidonic acid, remain controversial. To address this uncertainty and inform international recommendations, we evaluated how in vivo circulating and tissue levels of linoleic acid (LA) and arachidonic acid (AA) relate to incident cardiovascular disease (CVD) across multiple international studies.Methods:We performed harmonized, de novo, individual-level analyses in a global consortium of 30 prospective observational studies from 13 countries. Multivariable-adjusted associations of circulating and adipose tissue LA and AA biomarkers with incident total CVD and subtypes (coronary heart disease, ischemic stroke, cardiovascular mortality) were investigated according to a prespecified analytic plan. Levels of LA and AA, measured as the percentage of total fatty acids, were evaluated linearly according to their interquintile range (ie, the range between the midpoint of the first and fifth quintiles), and categorically by quintiles. Study-specific results were pooled using inverse-variance-weighted meta-analysis. Heterogeneity was explored by age, sex, race, diabetes mellitus, statin use, aspirin use, omega-3 levels, and fatty acid desaturase 1 genotype (when available).Results:In 30 prospective studies with medians of follow-up ranging 2.5 to 31.9 years, 15198 incident cardiovascular events occurred among 68659 participants. Higher levels of LA were significantly associated with lower risks of total CVD, cardiovascular mortality, and ischemic stroke, with hazard ratios per interquintile range of 0.93 (95% CI, 0.88-0.99), 0.78 (0.70-0.85), and 0.88 (0.79-0.98), respectively, and nonsignificantly with lower coronary heart disease risk (0.94; 0.88-1.00). Relationships were similar for LA evaluated across quintiles. AA levels were not associated with higher risk of cardiovascular outcomes; in a comparison of extreme quintiles, higher levels were associated with lower risk of total CVD (0.92; 0.86-0.99). No consistent heterogeneity by population subgroups was identified in the observed relationships.Conclusions:In pooled global analyses, higher in vivo circulating and tissue levels of LA and possibly AA were associated with lower risk of major cardiovascular events. These results support a favorable role for LA in CVD prevention.
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10. |
- Samuelsson, Mattias, 1976-, et al.
(författare)
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Growth of Ti-C nanocomposite films by reactive high power impulse magnetron sputtering under industrial conditions
- 2012
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Ingår i: Surface & Coatings Technology. - : Elsevier BV. - 0257-8972 .- 1879-3347. ; 206:8-9, s. 2396-2402
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Tidskriftsartikel (refereegranskat)abstract
- Titanium carbide (TiC) films were deposited employing high power impulse magnetron sputtering (HiPIMS) and direct current magnetron sputtering (DCMS) in an Ar-C2H2 atmosphere of various compositions. Analysis of the structural, bonding and compositional characteristics revealed that the deposited films are either TiC and hydrogenated amorphous carbon (a-C:H) nanocomposites, nanocrystalline TiC, or Ti/Tic, depending on the C/Ti ratio. It was found that Ti-C films grown by HiPIMS show a C/Ti ratio of close to 1 for a wide C2H2 flow range (4-15 sccm), with free C ranging from 0 to 20%. Thus, films ranging from near stoichiometric single phase TiC to TiC/a-C:H nanocomposites can be synthesized. This was not the case for DCMS, where films grown using similar deposition rates as for HiPIMS formed larger fractions of amorphous C matrix, thus being nanocomposites in the same C2H2 (above 4 sccm) flow range. For a C/Ti ratio of 1 the resistivity is low (4-8 x 10(2) mu Omega cm) for the HiPIMS films, and high (>100x 10(2) mu Omega cm) for the DCMS films. The hardness also shows a big difference with 20-27 and 6-10 GPa for HiPIMS and DCMS grown films, respectively.
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