| 31. |
- Eklund, Johan, 1991, et al.
(författare)
-
Field exposure of FeCrAl model alloys in a waste-fired boiler at 600°C: The influence of Cr and Si on the corrosion behaviour
- 2019
-
Ingår i: Materials and Corrosion. - : Wiley. - 0947-5117 .- 1521-4176. ; 70:8, s. 1476-1485
-
Tidskriftsartikel (refereegranskat)abstract
- Materials and Corrosion WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim The aim of this study was to examine the performance of FeCrAl model alloys in a waste-fired boiler and investigate the influence of chromium and silicon content on the corrosion behaviour. The investigation was executed by utilising an air-cooled probe, giving a material temperature of 600°C throughout a 672 hr exposure. The material loss measurements were performed by utilizing an ultrasonic thickness gauge in combination with scanning electron microscopy analysis. It was found that increasing the chromium content significantly reduced the overall material loss of the FeCrAl model alloys but further accelerated the corrosion attack on the windward side. Simultaneously, the increased chromium content caused embrittlement of the material. Minor additions of silicon drastically reduced the material loss of the FeCrAl model alloys, whereas the sample ring with no silicon present was completely deteriorated. The trends observed in this field study correlated well with what has been observed in previous laboratory studies. A state-of-the-art alloy in the present environment, Inconel 625, was simultaneously exposed and showed similar performance to the silicon-containing FeCrAl model alloys with ≥10 wt% Cr.
|
|
| 32. |
- Eklund, Johan, 1991, et al.
(författare)
-
The influence of silicon on the corrosion properties of FeCrAl model alloys in oxidizing environments at 600 °C
- 2018
-
Ingår i: Corrosion Science. - : Elsevier BV. - 0010-938X. ; 144, s. 266-276
-
Tidskriftsartikel (refereegranskat)abstract
- The present study investigates the influence of Si on the high temperature corrosion behaviour of FeCrAl model alloys in O2, O2+H2O and O2+H2O + KCl at 600 °C for up to 168 h. The investigation by SEM/EDX showed that all alloys displayed a protective behaviour in dry O2. In the more corrosive environments (O2+H2O and O2+H2O + KCl) the addition of Si affected the oxidation properties in two ways; Alloys containing Si resisted breakaway oxidation caused by Cr-evaporation (O2+H2O) and the thickness of the oxide formed after breakaway oxidation decreased with increasing amount of Si (O2+H2O + KCl).
|
|
| 33. |
- Folkeson, Nicklas, 1981, et al.
(författare)
-
Fireside corrosion of stainless and low alloyed steels in a waste-fired CFB boiler; The effect of adding sulphur to the fuel
- 2008
-
Ingår i: Materials Science Forum. ; 595-598, s. 289-297
-
Tidskriftsartikel (refereegranskat)abstract
- Corrosion field tests have been carried out in the superheater region of a commercial waste-fired 75MW CFBC boiler using air cooled probes. Exposure time was 24 and 1000 hours. The effect of adding sulphur to the fuel on the corrosion of two high alloyed steels and a low alloyed steel was studied. The fuel consisted of 50% household waste and 50% industrial waste. The exposed samples were analyzed by ESEM/EDX and XRD. Metal loss was determined after 1000 hours. Both materials suffered significant corrosion in the absence of sulphur addition and the addition of sulphur to the fuel reduced corrosion significantly. The rapid corrosion of the high alloyed steel in the absence of sulphur addition is caused by the destruction of the chromium-containing protective oxide by formation of calcium chromate. Adding sulphur to the fuel inhibited chromate formation and increased the sulphate/chloride ratio in the deposit. Iron(II) chloride formed on the low alloyed steel regardless of whether sulphur was added or not.
|
|
| 34. |
|
|
| 35. |
|
|
| 36. |
- Gilljam, Thomas, et al.
(författare)
-
Heart transplantation in arrhythmogenic right ventricular cardiomyopathy - Experience from the Nordic ARVC Registry
- 2018
-
Ingår i: International Journal of Cardiology. - : Elsevier BV. - 0167-5273 .- 1874-1754. ; 250, s. 201-206
-
Tidskriftsartikel (refereegranskat)abstract
- Objective: There is a paucity of data on heart transplantation (HTx) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC), and specific recommendations on indications for listing ARVC patients for HTx are lacking. In order to delineate features pertinent to HTx assessment, we explored the pre-HTx characteristics and clinical history in a cohort of ARVC patients who received heart transplants. Methods: Data from 31 ARVC/HTx patients enrolled in the Nordic ARVC Registry, transplanted between 1988 and 2014 at a median age of 46. years (14-65), were compared with data from 152 non-transplanted probands with Definite ARVC according to 2010 Task Force Criteria from the same registry. Results: The HTx patients were younger at presentation, median 31 vs. 38. years (p = 0.001). There was no difference in arrhythmia-related events. The indication for HTx was heart failure in 28 patients (90%) and ventricular arrhythmias in 3 patients (10%). During median follow-up of 4.9. years (0.04-28), there was one early death and two late deaths. Survival was 91% at 5. years after HTx. Age at first symptoms under 35. years independently predicted HTx in our cohort (OR = 7.59, 95% CI 2.69-21.39, p <. 0.001). Conclusion: HTx in patients with ARVC is performed predominantly due to heart failure. This suggests that current 2016 International Society for Heart and Lung Transplantation heart transplant listing recommendations for other cardiomyopathies could be applicable in many cases when taking into account the haemodynamic consequences of right ventricular failure in conjunction with ventricular arrhythmia.
|
|
| 37. |
- Haugaa, Kristina H, et al.
(författare)
-
Management of patients with Arrhythmogenic Right Ventricular Cardiomyopathy in the Nordic countries.
- 2015
-
Ingår i: Scandinavian Cardiovascular Journal. - : Informa UK Limited. - 1401-7431 .- 1651-2006. ; 49:6, s. 299-307
-
Forskningsöversikt (refereegranskat)abstract
- OBJECTIVES: Diagnostics of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) are complex, and based on the 2010 Task Force document including different diagnostic modalities. However, recommendations for clinical management and follow-up of patients with ARVC and their relatives are sparse. This paper aims to give a practical overview of management strategies, risk stratification, and selection of appropriate therapies for patients with ARVC and their family members.DESIGN: This paper summarizes follow-up and treatment strategies in ARVC patients in the Nordic countries. The author group represents cardiologists who are actively involved in the Nordic ARVC Registry which was established in 2009, and contains prospectively collected clinical data from more than 590 ARVC patients from Denmark, Norway, Sweden, and Finland.RESULTS: Different approaches of management and follow-up are required in patients with definite ARVC and in genetic-mutation-positive family members. Furthermore, ARVC patients with and without implantable cardioverter defibrillators (ICDs) require different follow-up strategies.CONCLUSION: Careful follow-up is required in patients with ARVC diagnosis to evaluate the need of anti-arrhythmic therapy and ICD implantation. Mutation-positive family members should be followed regularly for detection of early disease and risk stratification of ventricular arrhythmias.
|
|
| 38. |
- He, Hongxing, 1987, et al.
(författare)
-
Forests on drained agricultural peatland are potentially large sources of greenhouse gases – insights from a full rotation period simulation
- 2015
-
Ingår i: Biogeosciences Discussions. - : Copernicus GmbH. - 1810-6277. ; 12, s. 19673-19710
-
Tidskriftsartikel (refereegranskat)abstract
- The CoupModel was used to simulate a Norway Spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring data we obtained a "reference" model by which we were able to describe the fluxes and controlling factors over the 60 years. We discuss some conceptual issues relevant to improving the model in order to better understand peat soil simulations. However, the present model was able to describe the most important ecosystem dynamics such as the plant biomass development and GHG emissions. The GHG fluxes are composed of two important quantities, the forest carbon (C) uptake, 405 g C m−2 yr−1 and the decomposition of peat soil, 396 g C m−2 yr−1. N2O emissions contribute to the GHG emissions by 0.5 g N m−2 yr−1, corresponding to 56.8 g C m−2 yr−1. The 60-year-old Spruce forest has an accumulated biomass of 164 Mg C ha−1. However, over this period 208 Mg C ha−1 GHG has been added to the atmosphere, which means a net addition of GHG emissions. The main losses are from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding CO2 to the atmosphere.
|
|
| 39. |
- He, Hongxing, 1987, et al.
(författare)
-
Forests on drained agricultural peatland are potentially large sources of greenhouse gases – insights from a full rotation period simulation
- 2016
-
Ingår i: Biogeosciences. - : Copernicus GmbH. - 1726-4170 .- 1726-4189. ; 13, s. 2305-2318
-
Tidskriftsartikel (refereegranskat)abstract
- The CoupModel was used to simulate a Norway spruce forest on fertile drained peat over 60 years, from planting in 1951 until 2011, describing abiotic, biotic and greenhouse gas (GHG) emissions (CO2 and N2O). By calibrating the model against tree ring data a “vegetation fitted” model was obtained by which we were able to describe the fluxes and controlling factors over the 60 years. We discuss some conceptual issues relevant to improving the model in order to better understand peat soil simulations. However, the present model was able to describe the most important ecosystem dynamics such as the plant biomass development and GHG emissions. The GHG fluxes are composed of two important quantities, the spruce forest carbon (C) uptake, 413 g C m-2 yr-1 and the decomposition of peat soil, 399 gCm-2 yr-1. N2O emissions contribute to the GHG emissions by up to 0.7 gNm-2 yr-1, corresponding to 76 g Cm-2 yr-1. The 60-year old spruce forest has an accumulated biomass of 16.0 kg Cm-2 (corresponding to 60 kgCO2 m-2). However, over this period, 26.4 kg m-2 (97 kgCO2eqm-2) has been added to the atmosphere, as both CO2 and N2O originating from the peat soil and, indirectly, from forest thinning products, which we assume have a short lifetime. We conclude that after harvest at an age of 80 years, most of the stored biomass carbon is liable to be released, the system having captured C only temporarily and with a cost of disappeared peat, adding CO2 to the atmosphere.
|
|
| 40. |
|
|
