1. |
- Ahlroth, Mikael, et al.
(author)
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Bark and wood powder firing in the recovery boiler for maximum power generation
- 2017
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In: International chemical recovery conference, May 24-26, 2017, Halifax, Canada. - : PAPTAC.
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Conference paper (peer-reviewed)abstract
- The effect of co-firing bark or wood powder in a recovery boiler is studied. The effect of increased NPEs in the liquor and lime cycles, the FMT and sticky dust and the smelt composition is assessed by using simulation tools. The results indicate that generating an additional 22-39% HP steam for power production by firing wood powder in the recovery boiler is a viable option, if Cl and K are purged from the ESP dust by a treatment unit. The smelt is enriched with the same proportion of NPEs as the as-fired liquor.
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2. |
- Karlsson, Dennis, et al.
(author)
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Binder jetting of the AlCoCrFeNi alloy
- 2019
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In: Additive Manufacturing. - : Elsevier. - 2214-8604 .- 2214-7810. ; 27, s. 72-79
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Journal article (peer-reviewed)abstract
- High density components of an AlCoCrFeNi alloy, often described as a high-entropy alloy, were manufactured by binder jetting followed by sintering. Thermodynamic calculations using the CALPHAD approach show that the high-entropy alloy is only stable as a single phase in a narrow temperature range below the melting point. At all other temperatures, the alloy will form a mixture of phases, including a sigma phase, which can strongly influence the mechanical properties. The phase stabilities in built AlCoCrFeNi components were investigated by comparing the as-sintered samples with the post-sintering annealed samples at temperatures between 900 °C and 1300 °C. The as-sintered material shows a dominant B2/bcc structure with additional fcc phase in the grain boundaries and sigma phase precipitating in the grain interior. Annealing experiments between 1000 °C and 1100 °C inhibit the sigma phase and only a B2/bcc phase with a fcc phase is observed. Increasing the temperature further suppresses the fcc phase in favor for the B2/bcc phases. The mechanical properties are, as expected, dependent on the annealing temperature, with the higher annealing temperature giving an increase in yield strength from 1203 MPa to 1461 MPa and fracture strength from 1996 MPa to 2272 MPa. This can be explained by a hierarchical microstructure with nano-sized precipitates at higher annealing temperatures. The results enlighten the importance of microstructure control, which can be utilized in order to tune the mechanical properties of these alloys. Furthermore, an excellent oxidation resistance was observed with oxide layers with a thickness of less than 5 μm after 20 h annealing at 1200 °C, which would be of great importance for industrial applications.
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3. |
- Malmström, Mikael, 1982-, et al.
(author)
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Comparative study of structures in annealed 304 stainless steel using laser-ultrasonics (LUS) in combination with EBSD and XRD
- 2019
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Conference paper (peer-reviewed)abstract
- The material investigated was 304 (18/8) stainless steel that had been rolled with 70% at 700°C reduction to a final thickness of 2.9 mm. This warm rolling was chosen to avoid complications due to the formation of deformation martensite at room temperature. A 2.9x30x170 mm strip of the steel was then annealed in a controlled temperature gradient ranging from room temperature up to 1100°C so that all possible microstructural stages were represented, comprising recovery, recrystallisation and grain growth as well as their related texture changes. All measurements were made after cooling the specimen down to room temperature.Grain sizes were measured by LUS using the b-parameter analysis of attenuation data. In addition, the newly developed method for scanning the generating laser was applied to show the influence of texture on the anisotropy of wave velocities. Thus, both grain size and texture were continuously monitored along the length of the gradient annealed specimen.X-ray diffraction (XRD) was applied at various positions such that recovery and recrystallisation could be quantified using peak breadth measurements. In addition, microstructures and textures were determined using electron back-scattering diffraction (EBSD) at several locations corresponding to different annealing temperatures.All the observations were congruent in defining the location where primary recrystallisation had taken place over a relatively short distance on the specimen. The XRD line breadths dropped sharply and then remained constant after higher temperatures. However, the LUS grain sizes which also showed a sharp decrease then increased continuously as grain growth progressed, in good agreement with the EBSD observations. The anisotropic wave velocity results confirmed a significant change in the texture corresponding to recrystallisation despite the fact that EBSD showed that there was, in fact, only a modest weakening. A sensitive parameter defining recrystallisation was found to be the Poisson’s ratio which fell sharply and then increased very gradually up to the highest temperatures. This is interpreted as being due to the textural change during recrystallisation, followed by some sharpening of the annealing texture during subsequent grain growth.
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4. |
- Cedervall, Johan, et al.
(author)
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Magnetic and mechanical effects of Mn substitutions in AlFe2B2
- 2019
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In: Journal of Magnetism and Magnetic Materials. - : Elsevier BV. - 0304-8853 .- 1873-4766. ; 482, s. 54-60
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Journal article (peer-reviewed)abstract
- The mechanical and magnetic properties of the newly discovered MAB-phase class of materials based upon AlFe2B2 were investigated. The samples were synthesised from stoichiometric amounts of all constituent elements. X-ray diffraction shows that the main phase is orthorhombic with an elongated b-axis, similar to AlFe2B2. The low hardness and visual inspection of the samples after deformation indicate that these compounds are deformed via a delamination process. When substituting iron in AlFe2B2 with manganese, the magnetism in the system goes from being ferro- to antiferromagnetic via a disordered ferrimagnetic phase exhibited by AlFeMnB2. Density functional theory calculations indicate a weakening of the magnetic interactions among the transitions metal ions as iron is substituted by manganese in AlFe2B2. The Mn-Mn exchange interactions in AlMn2B2 are found to be very small.
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5. |
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6. |
- Cäker, Mikael, 1972, et al.
(author)
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When employee motivation varies: Agent- and steward-like interpretations of management control.
- 2015
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In: Interdisciplinary Perspectives on Accounting, Stockholm, 8-11 juli 2015.
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Conference paper (other academic/artistic)abstract
- Research on motivation has concluded how motivation differs on an individual level. However, this idea has failed to penetrate management control research, which pay attention the question of how employees are motivated. This article tries to start fill this gap, by aiming to increase our understanding of restrictions and possibilities with different management controls and their combinations, with respect to their influence on motivation, from a principal-agent and stewardship perspective. Based on a qualitative case study of a small, Swedish manufacturing organization, we find the dimensions of design and use to be relevant to understand dissimilar interpretations of management control from a stewardship and principal-agent perspective.
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7. |
- Gebauer, Denis, et al.
(author)
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Indications that Amorphous Calcium Carbonates Occur in Pathological Mineralisation-A Urinary Stone from a Guinea Pig
- 2018
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In: Minerals. - : MDPI AG. - 2075-163X. ; 8:3
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Journal article (peer-reviewed)abstract
- Calcium carbonate is an abundant biomineral that is of great importance in industrial or geological contexts. In recent years, many studies of the precipitation of CaCO3 have shown that amorphous precursors and intermediates are widespread in the biomineralization processes and can also be exploited in bio-inspired materials chemistry. In this work, the thorough investigation of a urinary stone of a guinea pig suggests that amorphous calcium carbonate (ACC) can play a role in pathological mineralization. Importantly, certain analytical techniques that are often applied in the corresponding analyses are sensitive only to crystalline CaCO3 and can misleadingly exclude the relevance of calcium carbonate during the formation of urinary stones. Our analyses suggest that ACC is the major constituent of the particular stone studied, which possibly precipitated on struvite nuclei. Minor amounts of urea, other stable inorganics, and minor organic inclusions are observed as well.
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8. |
- Godang, Kristin, et al.
(author)
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The effect of surgery on fat mass, lipid and glucose metabolism in mild primary hyperparathyroidism
- 2018
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In: Endocrine connections. - 2049-3614. ; 7:8, s. 941-948
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Journal article (peer-reviewed)abstract
- Mild primary hyperparathyroidism has been associated with increased body fat mass and unfavorable cardiovascular risk factors.To assess the effect of parathyroidectomy on fat mass, glucose and lipid metabolism.119 patients previously randomized to observation (OBS; n=58) or parathyroidectomy (PTX; n=61) within the Scandinavian Investigation of Primary Hyperparathyroidism (SIPH) trial, an open randomized multicenter study, were included. Main outcome measures for this study were the differences in fat mass, markers for lipid and glucose metabolism between OBS and PTX 5 years after randomization.In the OBS group, total cholesterol (Total-C) decreased from mean 5.9 (±1.1) to 5.6 (±1.0)mmol/L (P=0.037) and LDL cholesterol (LDL-C) decreased from 3.7 (±1.0) to 3.3 (±0.9)mmol/L (P=0.010). In the PTX group, the Total-C and LDL-C remained unchanged resulting in a significant between-group difference over time (P=0.013 and P=0.026, respectively). This difference was driven by patients who started with lipid-lowering medication during the study period (OBS: 5; PTX: 1). There was an increase in trunk fat mass in the OBS group, but no between-group differences over time. Mean 25(OH) vitamin D increased in the PTX group (P<0.001), but did not change in the OBS group. No difference in parameters of glucose metabolism was detected.In mild PHPT, the measured metabolic and cardiovascular risk factors were not modified by PTX. Observation seems safe and cardiovascular risk reduction should not be regarded as a separate indication for parathyroidectomy based on the results from this study.
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9. |
- Heimann, Mikael, et al.
(author)
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Utvecklingspsykologiska aspekter på tidig behandling av autism
- 2016
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In: Fokus på autism 6-8 april 2016, Karolinska institutet, Stockholm.
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Conference paper (other academic/artistic)abstract
- I den första presentationen presenteras resultat och erfarenheter från en europeisk enkät där 1680 föräldrar till små barn med autism i 20 olika länder fått svara på vilka insatser/interventioner som erbjuds och vilka de använt sig av. Därefter presenteras aktuell svensk forskning kring uppmärksamhetsfunktioner som en förutsättning för utveckling av samspel och intervention. Hur påverkar t ex uppmärksamhetsförmågan barn med autisms förmåga att skilja på meningsbärande och icke meningsbärande gester och vad kan förmågan till samordnad uppmärksamhet betyda för val av interventionsmetod? Slutligen kommer seminariet att avslutas med en presentation där verktygslådans innehåll för terapeuter som arbetar med tidiga insatser för barn med autism diskuteras. Erfarenheter av två olika interventionsmetoder, en övergripande manualbaserad metod bygd på ABA-strategier och en mer begränsad imitationsbaserad korttidsintervention, utgör grunden för denna avslutande presentation.
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10. |
- Henrohn, Dan, et al.
(author)
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Effects of Oral Supplementation With Nitrate-Rich Beetroot Juice in Patients With Pulmonary Arterial Hypertension-Results From BEET-PAH, an Exploratory Randomized, Double-Blind, Placebo-Controlled, Crossover Study.
- 2018
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In: Journal of Cardiac Failure. - : Elsevier BV. - 1071-9164 .- 1532-8414. ; 24:10, s. 640-653
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Journal article (peer-reviewed)abstract
- BACKGROUND: The nitrate-nitrite-nitric oxide (NO) pathway may represent a potential therapeutic target in patients with pulmonary arterial hypertension (PAH). We explored the effects of dietary nitrate supplementation, with the use of nitrate-rich beetroot juice (BRJ), in patients with PAH.METHODS AND RESULTS: We prospectively studied 15 patients with PAH in an exploratory randomized, double-blind, placebo-controlled, crossover trial. The patients received nitrate-rich beetroot juice (∼16 mmol nitrate per day) and placebo in 2 treatment periods of 7 days each. The assessments included; exhaled NO and NO flow-independent parameters (alveolar NO and bronchial NO flux), plasma and salivary nitrate and nitrite, biomarkers and metabolites of the NO-system, N-terminal pro-B-type natriuretic peptide, echocardiography, ergospirometry, diffusing capacity of the lung for carbon monoxide, and the 6-minute walk test. Compared with placebo ingestion of BRJ resulted in increases in; fractional exhaled NO at all flow-rates, alveolar NO concentrations and bronchial NO flux, and plasma and salivary levels of nitrate and nitrite. Plasma ornithine levels decreased and indices of relative arginine availability increased after BRJ compared to placebo. A decrease in breathing frequency was observed during ergospirometry after BRJ. A tendency for an improvement in right ventricular function was observed after ingestion of BRJ. In addition a tendency for an increase in the peak power output to peak oxygen consumption ratio (W peak/VO2 peak) was observed, which became significant in patients reaching an increase of plasma nitrite >30% (responders).CONCLUSIONS: BRJ administered for 1 week increases pulmonary NO production and the relative arginine bioavailability in patients with PAH, compared with placebo. An increase in the W peak/VO2 peak ratio was observed after BRJ ingestion in plasma nitrite responders. These findings indicate that supplementation with inorganic nitrate increase NO synthase-independent NO production from the nitrate-nitrite-NO pathway.
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