| 1. |
- Larsson, Cecilia, et al.
(författare)
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Measurement and modeling of residual stress in a welded Haynes® 25 cylinder
- 2005
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Ingår i: Materials Science & Engineering. - : Elsevier BV. - 0921-5093 .- 1873-4936. ; 399:1-2, s. 49-57
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Tidskriftsartikel (refereegranskat)abstract
- An experimental and simulation study of residual stresses was made in the vicinity of a gas tungsten arc weld, used to join a hemispherical end cap to a cylinder. The capped cylinder is used in a satellite application and was fabricated from a Co-based Haynes® 25 alloy. The cylinder was 34.7 mm in outer diameter and 3.3 mm in thickness. The experimental measurements were made by neutron diffraction and the simulation used the implicit Marc finite element code. The experimental resolution was limited to approximately 3 mm parallel to the axis of the cylinder (the weld was 6 mm in the same direction) and comparison over the same volume of the finite element prediction showed general agreement. Subject to the limited spatial resolution, the largest experimentally measured tensile residual stress was 180 MPa, located at the middle of the weld. However, the predictions suggest that there are regions in the weld where average tensile residual stresses as much as 400 MPa exist. One qualitative disparity between the model and the experiments was that the measurement included a larger degree of asymmetry on either side of the weld than predicted by the model.
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| 2. |
- Wilewska-Bien, Magda, 1977, et al.
(författare)
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Measures to reduce discharges and emissions
- 2016
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Ingår i: Shipping and the Environment: Improving Environmental Performance in Marine Transportation. - Berlin, Heidelberg : Springer Berlin Heidelberg. - 9783662490457 ; , s. 341-396
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Discharges and émissions from shipping can be reduced through different technical measures, many of which apply similar principies, e.g., filtration or absorption. Ballast water treatment systems can be used to limit the spread of invasive species. Selective catalytic reduction units and exhaust gas recirculation can be used to reduce nitrogen oxide emissions, and scrubbers and diesel particulate filters can be used to reduce sulphur dioxide and particle emissions. The restoration or remediation of natural environments may also be required after large oil spills. Possible remediation methods include booms, mechanical techniques and dispersant chemicals. These and several additional technical measures to reduce discharges and emissions are described in this chapter, including measures to reduce the impact of the infrastructure related to the shipping industry.
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