| 1. |
- Jansson, Anette, et al.
(författare)
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Effect of organic compounds on dry anaerobic digestion of food and paper industry wastes
- 2020
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Ingår i: Bioengineered. - : Taylor & Francis Group. - 2165-5979 .- 2165-5987. ; 11:1, s. 502-509
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Tidskriftsartikel (refereegranskat)abstract
- Effects of antimicrobial compounds on dry anaerobic digestion (dry-AD) processes were investigated. Four compounds with known inhibition effects on traditional wet digestion, i.e. car-3-ene, hexanal, 1-octanol and phenol were selected and investigated at concentrations of 0.005%, 0.05% and 0.5%. Food waste (FW) and Paper waste (PW) were used as model substrates, all assays were running with the substrate to inoculum ratio of 1:1 (VS basis) corresponding to 15% TS in reactors. Generally, increasing concentrations of inhibitors resulted in decreasing methane yields with a few exceptions; in all these specific cases, long, lag phase periods (60 days) were observed. These adaptation periods made possible for the microbial systems to acclimatize to otherwise not preferred conditions leading to higher methane yields. Comparing the effects of the four different groups, phenols had the highest inhibitory effects, with no methane production at the highest amount added, while the lowest effects were obtained in cases of car-3-ene. Furthermore, the results showed that adding inhibitors up to a certain concentrations can repair the balance in AD process, slowing down the degradation steps, hence making it possible for the methanogens to produce a higher amount of methane. This phenomenon was not observed in case of PW, which is already a slow degradable substrate in its nature.
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| 2. |
- Jansson, Anette, et al.
(författare)
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Dry Anaerobic Digestion of Food and Paper Industry Wastes at Different Solid Contents
- 2019
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Ingår i: Fermentation. - : MDPI. - 2311-5637. ; 5:2, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- A large volume of food is being wasted every year, while the pulp and paper industry also generate a large amount of solid wastes on a daily basis, causing environmental challenges around the world. Dry anaerobic digestion (AD) of these solid wastes is a cost-effective method for proper management. However, dry digestion of these waste streams has been restricted due to their complex structure, the presence of possible inhibitors and inappropriate operating conditions. In light of this fact, dry digestion of food waste (FW) and paper wastes (PW) was conducted at different total solid (TS) concentrations of reactor mixtures of 14%, 16%, 18% and 20% TS, corresponding to substrate to inoculum (S/I) ratio of 0.5 and 1; investigating the optimum operating conditions for effective dry digestion of these complex wastes. The highest methane yields of 402 NmlCH(4)/gVS and 229 NmlCH(4)/gVS were obtained from digestion of FW and PW, respectively at 14%TS corresponding to an S/I ratio of 0.5. Increasing the S/I ratio from 0.5 to 1 and thereby having a TS content of 20% in the reactor mixtures was unfavorable to the digestion of both substrates.
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| 3. |
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| 4. |
- Scandurra, Isabella, 1973-, et al.
(författare)
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Patient Accessible EHR is Controversial : Lack of Knowledge and Diverse Perceptions Among Professions
- 2017
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Ingår i: International Journal of Reliable and Quality E-Healthcare. - : IGI Global. - 2160-9551 .- 2160-956X. ; 6:1, s. 29-46
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Tidskriftsartikel (refereegranskat)abstract
- In Sweden, a national eHealth service providing Patient Accessible Electronic Health Records is now being widely deployed, with 400 000 users in January 2016. Although the Patient Data Act states that patients have a right to take part of their health records, the introduction has been controversial. Results from a pre-deployment questionnaire to record-keeping care professions in a healthcare region indicate that perceptions and knowledge differ not only between the professions but, more importantly, that knowledge about current eHealth development and action plans needs to increase as implementation will affect their work processes. Staff perceptions and knowledge are considered being some of the most important issues to handle during the implementation of eHealth services aiming to provide healthcare information and communication tools for patients and relatives. To cover the gaps, specific training is needed, and all record-keeping professionals need to be more involved in the implementation of such eHealth services.
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| 5. |
- Jansson, Anette, et al.
(författare)
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Pilot-Scale Experiments Using Cultivated Macro Algae for Biogas Production, Part of a Future Seafarm Biorefinery
- 2016
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Ingår i: 24th EUBCE Online Proceedings 2016. - : ETA-Florence Renewable Energies. - 9788889407165 ; , s. 627-629
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Konferensbidrag (refereegranskat)abstract
- The research is focused on evaluation of substrates not commonly used for biogas production and the development and optimization of processes adjusted to these substrates. This study deals with evaluation of sea weeds (Saccharina Lattisima and Laminaria digitata). Biomethane potential tests (BMP) have shown the methane potential of the algae to be 180-440 l CH4/kg organic material. These potentials are in the same range as potentials found for commonly used substrates such as sewage sludge and slaughterhouse waste. Sampling of produced biogas, substrate and digest were performed by using Solid Phase Microextraction (SPME) followed by analysis by a Gas Chromatograph with a Mass Spectrometrer (GC-MS) in order to develop a method to be able to characterize, monitor and possibly control the process.
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| 6. |
- Pechsiri, Joseph Santhi, et al.
(författare)
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Energy performance and greenhouse gas emissions of kelp cultivation for biogas and fertilizer recovery in Sweden
- 2016
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Ingår i: Science of the Total Environment. - : Elsevier. - 0048-9697 .- 1879-1026. ; 573, s. 347-355
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Tidskriftsartikel (refereegranskat)abstract
- The cultivation of seaweed as a feedstock for third generation biofuels is gathering interest in Europe, however, many questions remain unanswered in practise, notably regarding scales of operation, energy returns on investment (EROI) and greenhouse gas (GHG) emissions, all of which are crucial to determine commercial viability. This study performed an energy and GHG emissions analysis, using EROI and GHG savings potential respectively, as indicators of commercial viability for two systems: the Swedish Seafarm project's seaweed cultivation (0.5 ha), biogas and fertilizer biorefinery, and an estimation of the same system scaled up and adjusted to a cultivation of 10 ha. Based on a conservative estimate of biogas yield, neither the 0.5 ha case nor the up-scaled 10 ha estimates met the (commercial viability) target EROI of 3, nor the European Union Renewable Energy Directive GHG savings target of 60% for biofuels, however the potential for commercial viability was substantially improved by scaling up operations: GHG emissions and energy demand, per unit of biogas, was almost halved by scaling operations up by a factor of twenty, thereby approaching the EROI and GHG savings targets set, under beneficial biogas production conditions. Further analysis identified processes whose optimisations would have a large impact on energy use and emissions (such as anaerobic digestion) as well as others embodying potential for further economies of scale (such as harvesting), both of which would be of interest for future developments of kelp to biogas and fertilizer biorefineries.
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| 7. |
- Scandurra, Isabella, 1973-, et al.
(författare)
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Is 'patient's online access to health records' a good reform? : Opinions from Swedish healthcare professionals differ
- 2015
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Ingår i: Conference On Enterprise Information Systems/International Conference On Project Management/Conference On Health And Social Care Information Systems And Technologies, Centeris/Projman / Hcist 2015. - Amsterdam, Netherlands : Elsevier BV. ; 64, s. 964-968
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Konferensbidrag (refereegranskat)abstract
- Patients' access to their own electronic health record is a controversial issue. Many care professionals are concerned about negative effects deriving from patients reading their record information without support from clinicians. Patients on the other hand often think their concerns are outweighed by the benefits. In Sweden a pilot county has provided the health record online to its 350 000 patients for 2.5 years. This study highlights one of the most important questions to handle before and during implementation of such public eHealth services; the opinions of the care professionals regarding online records as a good reform. Results from three questionnaires to various care professions show that opinions from healthcare professionals differ not only between the professions but more importantly also between those who have experience from their patients reading their health record online and those who to date have no real experience. The experienced staff was more positive. This study concludes that in order to provide for successful national implementation, it is important to quickly elicit and disseminate opinions of care professionals with real experience to their unexperienced peers. Healthcare professionals should also be more involved in the implementation of Public eHealth services that regard electronic health records and their work processes.
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| 8. |
- Fall, David, 1983, et al.
(författare)
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Modelling cracking and bending failure of SFRC beams with conventional reinforcement
- 2013
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Ingår i: 8th International Conference on Fracture Mechanics of Concrete and Concrete Structures. - 9788494100413 ; , s. 1276-1285
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Konferensbidrag (refereegranskat)abstract
- In this study three beams, with varying contents of steel fibre reinforcement, were tested in four point bending and compared with results from FE-analysis. The beams were part of a larger experimental programme where relevant material properties were investigated. FE-modelling was performed using a two dimensional model. Concrete was represented by four-node quadrilateral isoperimetric plane stress elements. The smeared crack approach was utilized and the stress-strain relation describing the tensile behavior of the concrete was calculated from uni-axial test results, assuming the crack bandwidth to be equal to the element length. In compression, the concrete was assumed to behave elasto ideal-plastic. The reinforcement was modelled by straight 2-node truss elements connected to the concrete by two-dimensional interface elements providing the bond-slip properties. A material model including hardening effects was derived from tension tests of reinforcement bars and used for modelling the conventional reinforcement. A multi-linear bond-slip model was established through pull-out tests. As an alternative, analyses were also performed taking into account a reduction of the bond stress after yielding of the reinforcement occurred. Loading was applied in two phases: the first comprehending only the self-weight, while incremental loading was applied by deformation control during the second phase. General agreement between experiments and FE-analyses was obtained with regard to load-displacement behaviour. By observing the crack patterns, both from FE-analysis and experiments, it can be concluded that the general behaviour agreed; however, in the analyses not all cracks were fully localized. A higher degree of crack localization was obtained when the bond loss at yielding was included.
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| 9. |
- Fall, David, 1983, et al.
(författare)
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Non-linear Finite Element Analysis of Steel Fibre Reinforced Beams with Conventional Reinforcement
- 2012
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Ingår i: 8th RILEM International Symposium on Fiber Reinforced Concrete: challenges and opportunities (BEFIB 2012). - 9782351581322 ; , s. 1033-1045
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Konferensbidrag (refereegranskat)abstract
- The purpose of this study has been to investigate the behavior of elements reinforced with both conventional steel reinforcement and steel fibres in order to support future applications of such composites. Three beams of varying fibre content were tested in four-point bending. The results were then compared with results from nonlinear FE-analyses and the calculation method suggested in fib Model Code 2010. The beams were a part of a larger experimental programme where relevant properties were investigated in uniaxial tension tests and pull-out tests. The FE-modeling was performed using a two dimensional plane stress model. General agreement between experiments and the FE-analyses was obtained with regard to load-displacement behavior. The crack patterns from the FE-analysis and experiments agreed in general, although the crack patterns in the analysis were more distributed close to the reinforcement. Crack localization was enhanced by modifying the bond-slip behavior to include the bond loss at yielding. Calculations in accordance with fib Model Code 2010 yield conservative results in comparison with both experiments and FE-analysis.
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| 10. |
- Jansson, Anette M, 1963, et al.
(författare)
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Bond between Reinforcement and Self-Compacting Steel-Fibre-Reinforced Concrete
- 2012
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Ingår i: Proceeding of the Fourth International Conference on Bond in Concrete 2012: Bond, Anchorage, Detailing. ; 1, s. 323-329
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Konferensbidrag (refereegranskat)abstract
- In this study, pull-out tests of specimens with short embedment length and varying fibre content were carried out. The results showed no effect from the fibres on the bond-slip behaviour before peak load when normalized with respect to the compressive strength. After peak, the fibre reinforcement provided extra confinement, changing the failure mode from splitting to pull-out failure. The test results were used to calibrate a frictional bond model in non-linear finite element analyses. The model proved to yield results in good agreement with the experimental results regarding failure modes, load-slip relation and splitting strains on the surfaces of the pull-out specimens. The tests and analyses in combination confirmed that the fibre reinforcement neither disturbed nor improved the bond properties at the interface layer between reinforcement steel and concrete; i.e. the fibres only provided confinement to the surrounding structure.
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