| 1. |
- Forslund, Anna-Lena, 1964-, et al.
(författare)
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Direct repeat-mediated deletion of a type IV pilin gene results in major virulence attenuation of Francisella tularensis
- 2006
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Ingår i: Molecular Microbiology. - : Wiley-Blackwell. - 0950-382X .- 1365-2958. ; 59:6, s. 1818-1830
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Tidskriftsartikel (refereegranskat)abstract
- Francisella tularensis, the causative agent of tularaemia, is a highly infectious and virulent intracellular pathogen. There are two main human pathogenic subspecies, Francisella tularensis ssp. tularensis (type A), and Francisella tularensis ssp. holarctica (type B). So far, knowledge regarding key virulence determinants is limited but it is clear that intracellular survival and multiplication is one major virulence strategy of Francisella. In addition, genome sequencing has revealed the presence of genes encoding type IV pili (Tfp). One genomic region encoding three proteins with signatures typical for type IV pilins contained two 120 bp direct repeats. Here we establish that repeat-mediated loss of one of the putative pilin genes in a type B strain results in severe virulence attenuation in mice infected by subcutaneous route. Complementation of the mutant by introduction of the pilin gene in cis resulted in complete restoration of virulence. The level of attenuation was similar to that of the live vaccine strain and this strain was also found to lack the pilin gene as result of a similar deletion event mediated by the direct repeats. Presence of the pilin had no major effect on the ability to interact, survive and multiply inside macrophage-like cell lines. Importantly, the pilin-negative strain was impaired in its ability to spread from the initial site of infection to the spleen. Our findings indicate that this putative pilin is critical for Francisella infections that occur via peripheral routes.
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| 2. |
- Abdel-Magied, Ahmed Fawzy, et al.
(författare)
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Hierarchical porous zeolitic imidazolate framework nanoparticles for efficient adsorption of rare-earth elements
- 2019
-
Ingår i: Microporous and Mesoporous Materials. - : Elsevier. - 1387-1811 .- 1873-3093. ; 278, s. 175-184
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Tidskriftsartikel (refereegranskat)abstract
- Hierarchical porous zeolitic imidazolate frameworks nanoparticles (ZIF-8 NPs) were synthesized at room temperature via a template-free approach under dynamic conditions (stirring) using water as a solvent. The ZIF-8 NPs were evaluated as adsorbents for rare earth elements (La3+, Sm3+ and Dy3+). Adsorption equilibrium was reached after 7h and high adsorption capacities were obtained for dysprosium and samarium (430.4 and 281.1 mg g(-1), respectively) and moderate adsorption capacity for lanthanum (28.8 mg g(-1)) at a pH of 7.0. The high adsorption capacitiese, as well as the high stability of ZIF-8 NPs, make the hierarchical ZIF-8 materials as an efficient adsorbent for the recovery of La3+, Sm3+ and Dy3+ from aqueous solution.
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| 3. |
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| 4. |
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| 5. |
- Alemrajabi, Mahmood, 1989-, et al.
(författare)
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Isolation of rare earth element phosphate precipitate in the nitrophosphate process for manufacturing of fertilizer
- 2016
-
Ingår i: IMPC 2016 - 28th International Mineral Processing Congress. - : Canadian Institute of Mining, Metallurgy and Petroleum. - 9781926872292
-
Konferensbidrag (refereegranskat)abstract
- In the present study, the recovery of rare earth elements (REE) in the nitrophosphate process of fertilizer production is investigated. The apatite has been recovered from iron ore tailings by flotation. After digestion of apatite in concentrated nitric acid, Ca(NO3)2.4H2O is first separated by cooling crystallization and then the REEs are recovered by precipitation. Optimum conditions in these steps have been determined in a previous study. The precipitate mainly consists of CaHPO4.2H2O and REE phosphates. In the present study, selective dissolution and re-precipitation have been studied in order to obtain a precipitate that is more concentrated in REEs. The precipitate was selectively dissolved in nitric and phosphoric acid at different acidities (pH 6 to 0) with the liquid /solid ratio of 100 mL/g. It is shown that most of the CaHPO4.2H2O and other calcium containing compounds will be dissolved at pH 2 while the REE phosphates are not dissolved above a pH of approximately 2. Thus, by partial dissolution of the REE precipitate at pH 2.5 most of the solid calcium phosphates will be dissolved and the remaining solid phase, which is more concentrated in REEs, can be filtered off as a fairly concentrated REE solid mass and the liquor can be recycled back to recover more P nutrients. Alternatively, the REE enriched precipitate was dissolved completely in nitric acid and re-precipitated again by addition of ammonium hydroxide to pH 1.2. A chemical equilibrium software, MEDUSA (Puigdomenech, 2013) has been used to evaluate the experimental results and to estimate the optimum conditions for selectively dissolving the precipitate.
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| 6. |
- Alemrajabi, Mahmood, 1989-, et al.
(författare)
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Processing of a rare earth phosphate concentrate obtained in the nitrophosphate process of fertilizer production
- 2019
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Ingår i: Hydrometallurgy. - : Elsevier. - 0304-386X .- 1879-1158. ; 189
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Tidskriftsartikel (refereegranskat)abstract
- In this study, different processes have been developed and applied to treat a rare earth phosphate concentrate obtained within the nitrophosphate process of fertilizer production. Methods to remove impurities such as Fe and Ca have been investigated as well as to separate the phosphorous and thereby facilitate dissolution of the rare earth elements (REE). These methods include thermal treatment with sodium hydroxide and sodium double sulphate precipitation with and without alkaline conversion, followed by selective dissolution in different acids. The proposed processes were compared and analyzed from the perspective of introducing an appropriate intermediate product for further individual REE separation. The results have shown that after thermal treatment with NaOH at 400 °C, the phosphorous can be removed from the rare earth phosphate concentrate by water leaching. Investigation of different REE phosphate concentrates demonstrated that mixed Ca and REE phases, e.g. REEmCan(PO4)3m+2n/3 and CaHPO4 are less likely to dephosphorize than REE(PO4).nH2O and FePO4.H2O under these conditions. The recovery of REE to a mild acidic solution is limited by the presence of remaining phosphate ions and by the formation of REE oxide phases during the thermal treatment. The results also show that a solution containing 40 g/L REE; free of phosphorous, calcium and iron can be obtained after reprecipitation of the rare earth phosphate concentrate as sodium rare earth double sulphates followed by alkaline conversion with sodium hydroxide and dissolution in nitric acid.
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| 7. |
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| 8. |
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| 9. |
- Alemrajabi, Mahmood, 1989-
(författare)
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Recovery of Rare Earth Elements from an Apatite Concentrate
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Rare earth elements (REE) are a group of 17 elements including lanthanides, yttrium and scandium; which are found in a variety of classes of minerals worldwide. The criticality of the application, lack of high grade and economically feasible REE resources and a monopolistic supply situation has raised significant attention in recovery of these metals from low grade ores and waste materials. In this thesis, the recovery of REE from an apatite concentrate, containing 0.5 mass% of REE, within the nitrophosphate route of fertilizer production has been investigated. Most of the REE (≥ 95%) content can be recovered into a phosphate precipitate with almost 30 mass% REE. Different processes have been developed to convert the REE phosphate precipitate into a more soluble form to obtain a solution suitable for further REE purification and individual separation. It has been shown that after reprecipitation of the REE phosphate concentrate as REE sodium double sulphate and then transformation into a REE hydroxide concentrate, a solution containing 45g/L REE free of Ca, Fe and P can be obtained. The results suggest that the apatite waste after processing of iron ore have the potential to be a very important source for REE in Europe and that the economy is strongly supported by the simultaneous extraction of phosphorous.The potential of using hollow fiber supported liquid membrane (HFSLM) extraction in individual and group separation of REE has been investigated. A hollow fiber supported liquid membrane plant in pilot scale has been operated according to the three main configurations: standard hollow fiber supported liquid membrane technology (HFSLM); hollow fiber renewal liquid membrane technology (HFRSLM) and emulsion pertraction technology (EPT). The standard HFSLM operation is more selective than HFRSLM and EPT, while higher metal transport rate is observed in EPT followed by HFRSLM and HFSLM. The HFRLM configuration helps to maintain the performance of the liquid membrane.
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| 10. |
- Alemrajabi, Mahmood, et al.
(författare)
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Recovery of rare earth elements from nitrophosphoric acid solutions
- 2017
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Ingår i: Hydrometallurgy. - : Elsevier. - 0304-386X .- 1879-1158. ; 169, s. 253-262
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Tidskriftsartikel (refereegranskat)abstract
- In the present study, the recovery of rare earth elements (REEs) from an apatite concentrate in the nitrophosphate process of fertilizer production has been studied. The apatite concentrate has been recovered from iron ore tailings in Sweden by flotation. In the first step, the apatite is digested in concentrated nitric acid, after which Ca(NO3)2.4H2O is separated by cooling crystallization. The solution is then neutralized using ammonia whereby the REEs precipitate mainly as phosphates (REEPO4.nH2O) and together with calcium as REEn Cam (PO4)(3n + 2m) / 3. In this work, the degree of rare earth coprecipitation during seeded cooling crystallization of Ca(NO3)2.4H2O has been studied. The solubility of calcium nitrate tetrahydrate (Ca(NO3)2.4H2O) in acidic nitrophosphoric acid solutions in the temperature range of − 2 °C to 20 °C has been determined. For the neutralization step, it is shown that the calcium concentration and the final pH play an important role in determining the concentration of REEs in the precipitate. It is found that reaching maximum recovery of REE with minimum simultaneous precipitation of calcium requires careful control of the final pH to about 1.8. It is further observed that the precipitation yield of REEs and iron is favored by a longer residence time and higher temperature. Finally, the effect of seeding with synthesized REE phosphate crystals as well as a mixture of REE and Ca phosphates on the precipitation rate and the composition of the precipitate was studied.
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| 11. |
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| 12. |
- Alemrajabi, Mahmood, 1989-, et al.
(författare)
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Separation of Rare-Earth Elements Using Supported Liquid Membrane Extraction in Pilot Scale
- 2022
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Ingår i: Industrial & Engineering Chemistry Research. - : American Chemical Society (ACS). - 0888-5885 .- 1520-5045.
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Tidskriftsartikel (refereegranskat)abstract
- The use of supported liquid membrane extraction for recovery and separation of rare-earth elements (REEs) has been investigated. Experiments have been carried out using the different configurations: (1) standard hollow fiber supported liquid membrane operation (HFSLM), (2) renewal liquid membrane operation (HFRLM), and (3) emulsion pertraction technology (EPT). The experiments were performed in pilot scale using a hollow fiber module with a mass transfer surface area of 8 m2. Synthetic feed solution was used with compositions based on a process for recovery of REE from an apatite concentrate. The total concentration of REE in the feed was varied from 1 to 22 mM REE and the pH was varied in the range 1.5–3.2. Di(2-ethylhexyl) phosphoric acid (D2HEPA) diluted in kerosene, 10% (v/v), was used as the organic membrane solution, and 3 M HCl was used as stripping solution. In supported liquid membrane extraction, the extraction performance is governed by both the kinetics of REE transport through the membrane and by thermodynamics. The effect of feed composition on the selectivity and transport of REE through the liquid membrane have been investigated. The results show that the liquid membrane is more selective toward the heavy REE at lower pH values and higher REE concentration. HFRLM shows a higher transport rate than HFSLM, while the HFSLM configuration gives a higher selectivity toward individual REE. The membrane performance in HFSLM configuration rapidly decays with time, while in the HFRLM and EPT configurations, the performance is much more stable. Possible mechanisms for decaying membrane performance are discussed, and gel formation is identified as being of significant importance. Gel formation is observed at an organic loading above ∼46% for Nd, 38% for Y, 46% for Dy, and 65% for Er. The work performed in this study serves as an initial step to demonstrate that HFRLM and EPT can provide stable operation and be feasible options for processing of REE liquors. A process flow diagram for the recovery of the REE, present in the apatite concentrate, in three fractions is proposed based on the results from this study.
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| 13. |
- Alemrajabi, Mahmood, et al.
(författare)
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Upgrading of a rare earth phosphate concentrate within the nitrophosphate process
- 2018
-
Ingår i: Journal of Cleaner Production. - : Elsevier. - 0959-6526 .- 1879-1786. ; 198, s. 551-563
-
Tidskriftsartikel (refereegranskat)abstract
- In the nitrophosphate process of fertilizer production, rare earth elements (REE) can be recovered as a REE phosphate concentrate. In this process, after digestion of apatite in concentrated nitric acid, Ca(NO3)2.4H2O is first separated by cooling crystallization and then the REE are precipitated in phosphate form by a partial neutralization step using ammonia. The obtained REE phosphate concentrate is contaminated by mainly calcium and iron, and the main solid phases are CaHPO4.2H2O, FePO4.2H2O and REEPO4.nH2O.In this study, a process to obtain a concentrate more enriched with REE with low concentration of calcium and iron and free of phosphorous is developed. In the developed process, enrichment and dephosphorization of the rare earth phosphate concentrate has been achieved by selective dissolution and re-precipitation of the REE as a sodium REE double sulfate salt. It is shown that by selective dissolution of the REE concentrate in nitric acid at a pH of 2.4, most of the calcium and phosphorus are dissolved, and a solid phase more enriched in REE is obtained. Thereafter, the REE phosphate concentrate is first dissolved in a mixture of sulfuric-phosphoric acid and then the REE are reprecipitated as NaREE(SO4)2.H2O by addition of a sodium salt. More than 95% of the Ca, Fe and P are removed and a REE concentrate containing almost 30 mass% total REE is obtained.
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| 14. |
- Almung, Magnus, et al.
(författare)
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I solitärens skugga : Nyttobyggnadens kreativa restaurering
- 2015
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Rapport (populärvet., debatt m.m.)abstract
- Ekonomibyggnader har alltid behövts för de huvudbyggnader som finns inom våra bevarade kulturmiljöer. Några nyttobyggnader uppskattas och används fortfarande, andra betraktas som problematiska överloppsbyggnader, många rivs. Alltför få har dokumenterats eller fått sin historia klarlagd vilket undanhållit viktig kunskap om samhällets framväxt. Vi vill synliggöra och betona vikten av att bevara och utveckla hela bebyggelsemiljöer, ofta med ett antal hus utöver huvudbyggnaden och tillhörande yttre miljö i staden eller på landet. Denna rapport visar kursdeltagarnas projektarbeten om nyttobyggnader. De har dokumenterat med traditionella och nya arbetsmetoder, inventerat och intervjuat, läst och besökt arkiv, värderat, analyserat och därefter föreslagit hur man ska ta hand om och utveckla nyttobyggnaderna i sina kulturmiljöer.
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| 15. |
- Ashour, Radwa, et al.
(författare)
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DTPA-Functionalized Silica Nano- and Microparticles for Adsorption and Chromatographic Separation of Rare Earth Elements
- 2018
-
Ingår i: ACS Sustainable Chemistry and Engineering. - : American Chemical Society (ACS). - 2168-0485. ; 6:5, s. 6889-6900
-
Tidskriftsartikel (refereegranskat)abstract
- Silica nanoparticles and porous microparticles have been successfully functionalized with a monolayer of DTPA-derived ligands. The ligand grafting is chemically robust and does not appreciably influence the morphology or the structure of the material. The produced particles exhibit quick kinetics and high capacity for REE adsorption. The feasibility of using the DTPA-functionalized microparticles for chromatographic separation of rare earth elements has been investigated for different sample concentrations, elution modes, eluent concentrations, eluent flow rates, and column temperatures. Good separation of the La(III), Ce(III), Pr(III), Nd(III), and Dy(III) ions was achieved using HNO3 as eluent using a linear concentration gradient from 0 to 0.15 M over 55 min. The long-term performance of the functionalized column has been verified, with very little deterioration recorded over more than 50 experiments. The results of this study demonstrate the potential for using DTPA-functionalized silica particles in a chromatographic process for separating these valuable elements from waste sources, as an environmentally preferable alternative to standard solvent-intensive processes.
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| 16. |
- Ashour, Radwa M., et al.
(författare)
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Green Synthesis of Metal-Organic Framework Bacterial Cellulose Nanocomposites for Separation Applications
- 2020
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Ingår i: Polymers. - : MDPI AG. - 2073-4360. ; 12:5
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Tidskriftsartikel (refereegranskat)abstract
- Metal organic frameworks (MOFs) are porous crystalline materials that can be designed to act as selective adsorbents. Due to their high porosity they can possess very high adsorption capacities. However, overcoming the brittleness of these crystalline materials is a challenge for many industrial applications. In order to make use of MOFs for large-scale liquid phase separation processes they can be immobilized on solid supports. For this purpose, nanocellulose can be considered as a promising supporting material due to its high flexibility and biocompatibility. In this study a novel flexible nanocellulose MOF composite material was synthesised in aqueous media by a novel and straightforward in situ one-pot green method. The material consisted of MOF particles of the type MIL-100(Fe) (from Material Institute de Lavoisier, containing Fe(III) 1,3,5-benzenetricarboxylate) immobilized onto bacterial cellulose (BC) nanofibers. The novel nanocomposite material was applied to efficiently separate arsenic and Rhodamine B from aqueous solution, achieving adsorption capacities of 4.81, and 2.77 mg g‒1, respectively. The adsorption process could be well modelled by the nonlinear pseudo-second-order fitting.
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| 17. |
- Ashour, Radwa M., et al.
(författare)
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Selective separation of rare earth ions from aqueous solution using functionalized magnetite nanoparticles : kinetic and thermodynamic studies
- 2017
-
Ingår i: Chemical Engineering Journal. - : Elsevier. - 1385-8947 .- 1873-3212. ; 327, s. 286-296
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Tidskriftsartikel (refereegranskat)abstract
- Separation of rare earth ions (RE3+) from aqueous solution is a tricky problem due to their physico-chemical similarities of properties. In this study, we investigate the influence of the functionalized ligands on the adsorption efficiency and selective adsorption of La3+, Nd3+, Gd3+ and Y3+ from aqueous solution using Magnetite (Fe3O4) nanoparticles (NPs) functionalized with citric acid (CA@Fe3O4 NPs) or L-cysteine (Cys@Fe3O4 NPs). The microstructure, thermal behavior and surface functionalization of the synthesized nanoparticles were studied. The general adsorption capacity of Cys@Fe3O4 NPs was found to be high (98 mg g−1) in comparison to CA@Fe3O4 NPs (52 mg g−1) at neutral pH 7.0. The adsorption kinetic studies revealed that the adsorption of RE3+ ions follows a pseudo second-order model and the adsorption equilibrium data fits well to the Langmuir isotherm. Thermodynamic studies imply that the adsorption process was endothermic and spontaneous in nature. Controlled desorption within 30 min of the adsorbed RE3+ ions from both Cys@Fe3O4 NPs and CA@Fe3O4 NPs was achieved with 0.5 M HNO3. Furthermore, Cys@Fe3O4 NPs exhibited a higher separation factor (SF) in the separation of Gd3+/La3+, Gd3+/Nd3+, Gd3+/Y3+ ions compared to CA@Fe3O4 NPs.
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| 18. |
- Balachandran, Srija, et al.
(författare)
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Comparative study for selective lithium recovery via chemical transformations during incineration and dynamic pyrolysis of EV li-ion batteries
- 2021
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Ingår i: Metals. - : MDPI AG. - 2075-4701. ; 11:8
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Tidskriftsartikel (refereegranskat)abstract
- Selective leaching of Li from spent LIBs thermally pretreated by pyrolysis and incineration between 400 and 700 °C for 30, 60, and 90 min followed by water leaching at high temperature and high L/S ratio was examined. During the thermal pretreatment Li2CO3 and LiF were leached. Along with Li salts, AlF3 was also found to be leached with an efficiency not higher than 3.5%. The time of thermal pretreatment did not have a significant effect on Li leaching efficiency. The leaching efficiency of Li was higher with a higher L/S ratio. At a higher leaching temperature (80 °C), the leaching of Li was higher due to an increase in the solubility of present Li salts. The highest Li leaching efficiency of nearly 60% was observed from the sample pyrolyzed at 700 °C for 60 min under the leaching condition L/S ratio of 20:1 mL g−1 at 80 °C for 3 h. Furthermore, the use of an excess of 10% of carbon in a form of graphite during the thermal treatment did not improve the leaching efficiency of Li.
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| 19. |
- Bejerot, Eva, 1951-, et al.
(författare)
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Akutmottagningarnas konstanta kaos : styrning, det oförutsedda och motstånd
- 2015
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Ingår i: Book of Abstracts FALF 2015 Conference 10.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Under många år har det funnits ett brett missnöje med långa väntetider på akutmottagningarna på svenska sjukhus. Media har skrivit mycket om detta område, politiker och huvudmän har introducerat en rad interven-tioner och myndigheter har inspekterat, mätt och jämfört för att stimulera ”best practice”. Men resultatet av allt detta är negativt – väntetiderna på akutmottagningarna har ökat under senare år! Vad kan detta bero på? Kan orsaken vara att styrformerna varit felaktigt utformade, att det under perioden skett andra förändringar vars effekter beslutsfattarna inte förutsåg, eller kan det vara läkargruppens motstånd till effektiviserande åtgärder som ligger bakom uteblivna förbättringar? I denna studie beskrivs dels de politiska initiativ och interventioner som gjorts på nationell nivå för att komma tillrätta med väntetiderna under 2010-talet, dels utfallet av dessa insatser så som de uppfattas av läkare som arbetar på akutmottagningar. I analysen intresserar vi oss särskilt för läkarnas inflytande och eventuella motstånd till förändringar.Initialt gjordes intervjuer med 14 läkare som arbetar på akutmottagningar på fyra sjukhus. De tillhör både den nya specialiteten akutvårdsläkare och andra specialiteter som är “gästdoktorer” på akuten. Intervjuerna gjor-des för att få kunskap inför en enkätundersökning, och har för detta arbete analyserats tematiskt med fokus på styrning, förändringar och dilemman i arbetet. Efter analysen av intervjuerna och identifiering av de styrfor-mer som respondenterna tog upp, studerades de rapporter och beslut som låg bakom dessa styrformer. Vilken kunskap baserades de på? Vilka hade inflytande på utformningen av förändringarna? Hur har styrningen anpassats över tid i relation till de svårigheter som akutmottagningarna har att klar av att möta målen?Den styrning som de intervjuade läkarna tar upp som kontraproduktiv är relaterad till överorganisatoriska direktiv och mål som är kopplade till prestationsmätningar av olika slag. Ett par exempel: För akutmottag-ningarna finns landstingsspecifika mål att i stort sett alla patienter på akuten ska vara färdigbehandlade inom fyra timmar. Det är ett mål som ständigt fallerar, som medför negativa ekonomiska konsekvenser för kliniken, men framför allt ger en känsla av misslyckande. På vissa enheter har styrningen lett till att man organiserat om arbetet för att förbättra mätresultaten – inte vården. Andra förändringar handlar om ett nationellt föränd-ringsprogram för att med stöd av lean effektivisera arbetssättet, det vill säga hur arbetsuppgifterna organiseras på mottagningarna. Även här beskriver respondenterna problem avseende arbetmiljö och vårdkvalitet.Analysen indikerar att styrformerna utmanar den professionella identiteten och skapar nya dilemman. Men det finns i praktiken inga möjligheter för läkarna att göra motstånd; man kan föra fram synpunkter, men de beaktas inte, man kan på individnivå strunta i något delmoment, men det är i det lilla. Resultaten diskuteras i termer av makt och motstånd. I förlängningen bör denna studie utvidgas med intervjuer av chefer och besluts-fattare.
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| 20. |
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| 21. |
- Bejerot, Eva, 1951-, et al.
(författare)
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Occupational Control on Drift : National and Local Intervention in Clinical Work at Emergency Departments
- 2017
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Ingår i: Professions & Professionalism. - : Høgskolen i Oslo og Akershus. - 1893-1049. ; 7:2, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- In Swedish emergency departments, various initiatives have been introduced in order to reduce long waiting times for patients: lean methods, targets for waiting times related to revenues, interprofessional teams, and different forms of triage systems. This study focuses on the physicians’ views on dilemmas related to these interventions. The study is based on the interviews with 14 physicians in four emergency departments. The interviews have been analysed thematically and presented in the form of brief narratives. The study follows changes from clinical practice to the national policy level. The changes appear to be ineffective or counterproductive—waiting times are rather getting longer, but the measures have a number of other effects. Decisions are taken at a central level and are carried out by means of rules, incentives, and projects and end in the medical profession being displaced from the central position they have held in the working processes of health care.
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| 22. |
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| 23. |
- Bretzer, Ylva, et al.
(författare)
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Lokal översättning av de nationella miljömålen : En processutvärdering i åtta svenska kommuner 2006
- 2006
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Förord Naturvårdsverket fick 2006 i uppdrag av regeringen att redovisa hur miljömålsarbetet bedrivs i landets kommuner. Verket skulle främst redovisa vilken omfattning arbetet med miljökvalitetsmålen har, vilka mål som prioriterats och valts bort samt skälen till det, om lokala mål utarbetats, hur samarbetet sker inom kommunen och mellan kommunen och andra myndigheter samt slutligen hinder och möjligheter i miljömålsarbetet. För att genomföra redovisningen har Naturvårdsverket gett statsvetenskapliga forskare i Göteborg (vid Göteborgs universitet, vid Centrum för forskning om offentlig sektor och vid Förvaltningshögskolan) och i Umeå (vid Umeå Center for Evaluation Studies) i uppdrag att genom enkäter och intervjuer studera kommunernas miljömålsarbete. Verket har dessutom använt rapporter från Sveriges Kommuner och Landsting (SKL). Här publiceras forskarnas rapporter: Lokal översättning av de nationella miljömålen – En processutvärdering i åtta svenska kommuner 2006 samt i bilaga Miljöprioriteringar i Sveriges kommuner – En analys av kommunernas prioritering av de femton miljömålen.Författarna svarar själva för innehållet i rapporterna, som således inte nödvändigtvis återspeglar Naturvårdsverkets uppfattning. Naturvårdsverket i november 2006Författarnas förord Den här rapporten har tillkommit i första hand med syftet att följa upp hur det går med miljömålsarbetet i ett urval av kommuner. En första sådan utvärdering gjordes redan 2003 (Kommunerna och miljömålen − en utvärdering, SNV rapport 5265) och således blir detta den andra rapporten som följer åtta olika kommunala processer för att genomföra det av riksdagen beslutade miljömålsarbetet. En utvärdering ska i första hand värdera. I detta fall hade det varit naturligt att göra en utvärdering över tid, vilket i strikt bemärkelse tyvärr inte har varit möjlig att genomföra, då vi saknat tillgång till det ursprungliga frågematerialet. Denna rapport kan dock med fördel läsas för att få en övergripande tvärsnittsbild av hur miljömålsarbetet har fortsatt och vilka ytterligare förbättringar som kan göras. Vi tror därmed att värderingen som görs i vår rapport kommer att vara till nytta för aktörer inom fältet, och att kommande utvärderingar kan bygga vidare på dess resultat. Vår måttstock utgår i första hand från våra läsningar av statliga propositioner och politiska målsättningar inom miljömålsarbetet, men vi lägger också våra egna forskarmässiga värderingar i vårt sätt att tolka materialet. Vi har fått ta del av ett rikt material som inte på något sätt fullt ut kan redogöras inom ramen för denna rapport. Vi vill rikta ett varmt tack till alla uppgiftslämnare i kommunerna som på ett frikostigt sätt har delat med sig av sina erfarenheter och uppfattningar. Ert bidrag har varit en förutsättning för studiens genomförande. De slutliga tolkningarna − och dess brister − svarar dock vi som författare själva för. I så hög grad som möjligt, eller där det har varit relevant, har vi anonymiserat materialet. Vi vill också rikta vår tacksamhet till en rad andra aktörer. Flera konstruktiva möten har hållits tillsammans med vår uppdragsgivare Naturvårdsverket och representanter för Sveriges Kommuner och Landsting (SKL). Särskilt vill vi tacka Stig Wandén på Naturvårdsverket och Andreas Hagnell på SKL för de frikostiga och konstruktiva kommentarer som vi fått. Även fil dr Martin Bennulf som för närvarande forskar och undervisar vid Södertörns högskola har varit en viktig initiativtagare och resursperson under arbetet. Rapporten har tillkommit genom ett forskningssamarbete mellan Centrum för forskning om offentlig sektor (CEFOS) i Göteborg, Förvaltningshögskolan i Göteborg och Umeå Center for Evaluation Studies (UCER) och med denna rapport har ett viktigt samarbetssteg tagits mellan dessa parter. Assistent Kristian Frenander har bistått projektet med utskrifter av flertalet intervjuer. Alla dessa vill vi rikta vårt varmaste tack till för det sätt på vilket ni har bidragit till att detta uppdrag nu är slutfört. Göteborg och Umeå i september 2006
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| 24. |
- Carneiro, Miguel, et al.
(författare)
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Rabbit genome analysis reveals a polygenic basis for phenotypic change during domestication
- 2014
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 345:6200, s. 1074-1079
-
Tidskriftsartikel (refereegranskat)abstract
- The genetic changes underlying the initial steps of animal domestication are still poorly understood. We generated a high-quality reference genome for the rabbit and compared it to resequencing data from populations of wild and domestic rabbits. We identified more than 100 selective sweeps specific to domestic rabbits but only a relatively small number of fixed (or nearly fixed) single-nucleotide polymorphisms (SNPs) for derived alleles. SNPs with marked allele frequency differences between wild and domestic rabbits were enriched for conserved noncoding sites. Enrichment analyses suggest that genes affecting brain and neuronal development have often been targeted during domestication. We propose that because of a truly complex genetic background, tame behavior in rabbits and other domestic animals evolved by shifts in allele frequencies at many loci, rather than by critical changes at only a few domestication loci.
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| 25. |
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| 26. |
- Chen, Song, et al.
(författare)
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Eu3+ doped monetite and its use as fluorescent agent for dental restorations
- 2018
-
Ingår i: Ceramics International. - : Saunders Elsevier. - 0272-8842 .- 1873-3956. ; 44:9, s. 10510-10516
-
Tidskriftsartikel (refereegranskat)abstract
- It is essential but challenging to distinguish the dental restorations from the surrounding teeth when removing filling materials from cavity. In this study, Eu3+ doped monetite was proposed as a fluorescent agent for dental restorations to meet this challenge. Eu3+ doped monetite with enhanced fluorescent property was obtained via a precipitation method. The presence of Eu3+ could prevent the phase transformation of brushite to monetite. However, all the brushite particles transformed to monetite at 300 °C and to tricalcium phosphate at 800 °C. The emission intensity increased with the addition of Eu3+ and reached the maximum when 12 mol% Eu3+ was added into the aqueous solution. With either 254 nm or 393 nm excitation, Eu3+ doped monetite showed the strongest fluorescence emission peaking at 616 nm and other two moderate bands peaking at 699 nm and 593 nm. The excitation spectra at the emission wavelength of 616 nm showed strong absorption peaks at 254 nm and 393 nm. We further investigate the fluorescence properties of Eu3+ doped monetite in one type of dental restorations. Glass ionomer cement with Eu3+ doped monetite exhibited clear fluoresce with origin color under UV irradiation at 254 nm, showing that Eu3+doped monetite is a promising fluorescent agent for dental restorations.
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| 27. |
- Chen, Song, et al.
(författare)
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Incorporation of strontium and europium in crystals of α-calcium isosaccharinate
- 2019
-
Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 364, s. 309-316
-
Tidskriftsartikel (refereegranskat)abstract
- The final repository for short-lived, low and intermediate level radioactive waste in Sweden is built to act as a passive repository. Already within a few years after closure water will penetrate the repository and conditions of high alkalinity (pH 10.5―13.5) and low temperature (< 7 °C) will prevail. The mobility of radionuclides in the repository is dependent on the radionuclides distribution between solid and liquid phases. In the present work the incorporation of strontium (II) and europium (III) in α-calcium isosaccharinate (ISA) under alkaline conditions (pH ~10) at 5 °C and 50 °C have been studied. The results show that strontium and europium are incorporated into α-Ca(ISA)2 when crystallized both at 5 °C and 50 °C. Europium is incorporated to a greater extent than strontium. The highest incorporation of europium and strontium at 5 °C rendered the phase compositions Ca0.986Eu0.014(ISA)2 (2.4% of Eu(ISA)3 by mass) and Ca0.98Sr0.02(ISA)2 (2.2% of Sr(ISA)2 by mass). XPS spectra show that both trivalent and divalent Eu coexist in the Eu incorporated samples. Strontium ions were found to retard the elongated growth of the Ca(ISA)2crystals. The incorporation of Sr2+ and Eu3+ into the solid phase of Ca(ISA)2 is expected to contribute to a decreased mobility of these ions in the repository.
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| 28. |
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| 29. |
- Chernyshev, Alexander N., et al.
(författare)
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Characterization and degradation of a polyaryl ether based superplasticizer for use in concrete barriers in deep geological repositories
- 2018
-
Ingår i: Applied Geochemistry. - : Elsevier. - 0883-2927 .- 1872-9134. ; 95, s. 172-181
-
Tidskriftsartikel (refereegranskat)abstract
- Superplasticizers are important additives used in concrete barriers in geological waste repositories. Superplasticizers have been a major concern in the long-term assessments of safe geological disposal for radioactive waste since superplasticizers and their degradation products can act as complexing ligands and thereby increase the mobility of radionuclides. In this work a new type of superplasticizer, based on a polyaryl ether polymer, has been characterized. It was found that the superplasticizer combines the structural features of polycarboxylate ether based superplasticizers and sulfonated naphthalene-formaldehyde based superplasticizers and that it contains organophosphatecharged groups. A novel method for evaluating the rate of degradation of the superplasticizer under alkaline conditions was elaborated and the degradation products and rate constant of the process was determined. The results demonstrate that degradation occurs rapidly compared to the typical lifetime of a repository.
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| 30. |
- Chernyshev, Alexander N., et al.
(författare)
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Solubilization of Ni(II) and Eu(III) through complexation with a polyaryl ether based superplasticizer in alkaline media
- 2021
-
Ingår i: Chemosphere. - : Elsevier BV. - 0045-6535 .- 1879-1298. ; 263
-
Tidskriftsartikel (refereegranskat)abstract
- Solubilisation of Ni(II) and Eu(III) by complexation with a polyaryl ether based superplasticizer (PAE SP) in alkaline solutions was studied. The solubilization was investigated in two types of artificial cement pore waters simulating different stages of cement degradation at a pH of 12.4 and 13.3, respectively. The solubility of Ni(II) and Eu(III) increased as the concentration of superplasticizer was increased from 0.04 to 0.4 wt%. When the concentration of SP was increased from 0.4 to 4%, the solubility of Eu(III) and Ni(II) increased in the pore water with a pH of 12.4, while the concentrations decreased in the pore water with a pH of 13.3. This is explained by a more rapid degradation of the superplasticizer at higher pH leading to a release of phosphate groups and thereby precipitation of Eu(III) and Ni(II) as phosphates. Based on results of the solubilisation of Ni(II) and Eu(III) by model compounds (anisole and PEG 400) and 31P NMR spectroscopy it was confirmed that the complexation of the studied metals with the PAE polymer occurs via the phosphate group of the superplasticizer.
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| 31. |
- Degerman Engfeldt, Johnny, 1982-
(författare)
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Predicting Electrochromic Smart Window Performance
- 2012
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The building sector is one of the largest consumers of energy, where the cooling of buildings accounts for a large portion of the total energy consumption. Electrochromic (EC) smart windows have a great potential for increasing indoor comfort and saving large amounts of energy for buildings. An EC device can be viewed as a thin-film electrical battery whose charging state is manifested in optical absorption, i.e. the optical absorption increases with increased state-of-charge (SOC) and decreases with decreased state-of-charge. It is the EC technology's unique ability to control the absorption (transmittance) of solar energy and visible light in windows with small energy effort that can reduce buildings' cooling needs. Today, the EC technology is used to produce small windows and car rearview mirrors, and to reach the construction market it is crucial to be able to produce large area EC devices with satisfactory performance. A challenge with up-scaling is to design the EC device system with a rapid and uniform coloration (charging) and bleaching (discharging). In addition, up-scaling the EC technology is a large economic risk due to its expensive production equipment, thus making the choice of EC material and system extremely critical. Although this is a well-known issue, little work has been done to address and solve these problems. This thesis introduces a cost-efficient methodology, validated with experimental data, capable of predicting and optimizing EC device systems' performance in large area applications, such as EC smart windows. This methodology consists of an experimental set-up, experimental procedures and a twodimensional current distribution model. The experimental set-up, based on camera vision, is used in performing experimental procedures to develop and validate the model and methodology. The two-dimensional current distribution model takes secondary current distribution with charge transfer resistance, ohmic and time-dependent effects into account. Model simulations are done by numerically solving the model's differential equations using a finite element method. The methodology is validated with large area experiments. To show the advantage of using a well-functioning current distribution model as a design tool, some EC window size coloration and bleaching predictions are also included. These predictions show that the transparent conductor resistance greatly affects the performance of EC smart windows.
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| 32. |
- Diesen, Veronica, et al.
(författare)
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Effects of cellulose degradation products on the mobility of Eu(III) in repositories for low and intermediate level radioactive waste
- 2017
-
Ingår i: Journal of Hazardous Materials. - : Elsevier. - 0304-3894 .- 1873-3336. ; 340, s. 384-389
-
Tidskriftsartikel (refereegranskat)abstract
- The deep repository for low and intermediate level radioactive waste SFR in Sweden will contain large amounts of cellulosic waste materials contaminated with radionuclides. Over time the repository will be filled with water and alkaline conditions will prevail. In the present study degradation of cellulosic materials and the ability of cellulosic degradation products to solubilize and thereby mobilise Eu(III) under repository conditions has been investigated. Further, the possible immobilization of Eu(III) by sorption onto cement in the presence of degradation products has been investigated. The cellulosic material has been degraded under anaerobic and aerobic conditions in alkaline media (pH: 12.5) at ambient temperature. The degradation was followed by measuring the total organic carbon (TOC) content in the aqueous phase as a function of time. After 173 days of degradation the TOC content is highest in the anaerobic artificial cement pore water (1547 mg/L). The degradation products are capable of solubilising Eu(III) and the total europium concentration in the aqueous phase was 900 μmol/L after 498 h contact time under anaerobic conditions. Further it is shown that Eu(III) is adsorbed to the hydrated cement to a low extent (<9 μmol Eu/g of cement) in the presence of degradation products.
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| 33. |
- Duwig, Christophe
(creator_code:cre_t)
-
Exhibition : Towards the energy of the future – the invisible revolution behind the electrical socket
- 2023
-
Konstnärligt arbeteabstract
- Energy Crisis! Electricity Price drama! The threat of global energy poverty! Media are generous with spectacular titles. Yes, energy is important, and yes, nearly all societal challenges are connected to how we convert, distribute and use energy. Therefore, the KTH Energy Platform and KTH Library presented an exhibition with the theme Towards the energy of the future – the invisible revolution behind the electrical socket.The exhibition displayed showcase illustrations from the book made by Lotta Waesterberg Tomasson, as well as books related to energy and electricity from the KTH Library's collections. In parallell with the exhibition, a series of live popular science lunch seminars with presentations of selected chapters of the book took place. As part of the exhibition, students from KTH's Electrical Engineering program also showcased exciting projects that connect to the anthology’s contents, made with materials and equipment from the student-driven ELAB and “Studentverkstan”. Visitors were also invited to share their reflections and ideas on energy.
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| 34. |
- Egge-Jacobsen, Wolfgang, et al.
(författare)
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O-Linked glycosylation of the PilA pilin protein of francisella tularensis : identification of the endogenous protein-targeting oligosaccharyltransferase and characterization of the native oligosaccharide
- 2011
-
Ingår i: Journal of Bacteriology. - Baltimore : Williams & Wilkins. - 0021-9193 .- 1098-5530. ; 193:19, s. 5487-5497
-
Tidskriftsartikel (refereegranskat)abstract
- Findings from a number of studies suggest that the PilA pilin proteins may play an important role in the pathogenesis of disease caused by species within the genus Francisella. As such, a thorough understanding of PilA structure and chemistry is warranted. Here, we definitively identified the PglA protein-targeting oligosaccharyltransferase by virtue of its necessity for PilA glycosylation in Francisella tularensis and its sufficiency for PilA glycosylation in Escherichia coli. In addition, we used mass spectrometry to examine PilA affinity purified from Francisella tularensis subsp. tularensis and F. tularensis subsp. holarctica and demonstrated that the protein undergoes multisite, O-linked glycosylation with a pentasaccharide of the structure HexNac-HexHex-HexNac-HexNac. Further analyses revealed microheterogeneity related to forms of the pentasaccharide carrying unusual moieties linked to the distal sugar via a phosphate bridge. Type A and type B strains of Francisella subspecies thus express an O-linked protein glycosylation system utilizing core biosynthetic and assembly pathways conserved in other members of the proteobacteria. As PglA appears to be highly conserved in Francisella species, O-linked protein glycosylation may be a feature common to members of this genus.
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| 35. |
- F. Abdel-Magied, Ahmed, et al.
(författare)
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Magnetic metal-organic frameworks for efficient removal of cadmium(II), and lead(II) from aqueous solution
- 2022
-
Ingår i: Journal of Environmental Chemical Engineering. - : Elsevier BV. - 2213-2929 .- 2213-3437. ; 10:3
-
Tidskriftsartikel (refereegranskat)abstract
- Efficient and convenient methods for the removal of toxic heavy metal ions especially Cd(II) and Pb(II) from aqueous solutions is of great importance due to their serious threat to public health and the ecological system. In this study, two magnetic metal-organic frameworks (namely: Fe3O4@ZIF-8, and Fe3O4@UiO-66–NH2) were synthesized, fully characterized, and applied for the adsorption of Cd(II) and Pb(II) from aqueous solutions. The adsorption efficiencies for the prepared nanocomposites are strongly dependent on the pH of the aqueous solution. The maximum adsorption capacities of Fe3O4@UiO-66–NH2, and Fe3O4@ZIF-8 at pH 6.0 were calculated to be 714.3 mg·g−, and 370 mg·g−1 for Cd(II), respectively, and 833.3 mg·g−1, and 666.7 mg·g−1 for Pb(II), respectively. The adsorption process follows a pseudo-second-order model and fit the Langmuir isotherm model. Moreover, the thermodynamic studies revealed that the adsorption process is endothermic, and spontaneous in nature. A plausible adsorption mechanism was discussed in detail. The magnetic adsorbents: Fe3O4@ZIF-8, and Fe3O4@UiO-66–NH2 showed excellent reusability, maintaining the same efficiency for at least four consecutive cycles. These results reveal the potential use of magnetic Fe3O4@ZIF-8, and Fe3O4@UiO-66–NH2 as efficient adsorbents in removing Cd(II) and Pb(II) from aqueous solutions.
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| 36. |
- Forsberg, David, et al.
(författare)
-
AIM in Neonatal and Pediatric Intensive Care
- 2022. - 1st
-
Ingår i: Artificial Intelligence in Medicine. - Cham : Springer Nature. ; , s. 1047-1056
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Infections are one of the leading causes of death in infants and detecting life-threatening events in infants is challenging. Thus, providing effective life-saving interventions in time is essential. As infants’ immune and autonomic control system are under development, signs preceding potentially life-threatening events are subtle. Clinical detection is aided by analysis of biomarkers, which unfortunately requires invasive sampling and is time consuming. Infection and inflammation interfere with the autonomic control systems and consequently affect vital signs. Constantly monitoring vital signs at a high frequency enables the immediate detection of discrepancies and is thus a key, noninvasive instrument in modern intensive care units. For pediatric intensive care, several predictive monitoring systems have been developed over the last decade that aim to utilize vital sign monitoring to mitigate the risk of developing lifethreatening events, such as sepsis. Recent advances in the field of machine learning have provided novel techniques for big data analysis. This enables an individualized risk assessment via continuous multimodal inputs and development of better clinical decision support systems. These more advanced systems are able to detect sepsis 24 hours earlier than clinical practice and enable an overall risk assessment for future sepsis, life-threatening events, and death at the time of hospitalization or during the first week of life. This chapter summarizes the current evidence on machine learning-based monitoring systems and provides an overview on the strengths, limitations, and potential future roles of novel machine learning-based methods for the early detection of pedatric sepsis and potentially life-threatening events.
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| 37. |
- Forsberg, Kerstin, et al.
(författare)
-
Crystal growth kinetics of iron fluoride trihydrate
- 2006
-
Ingår i: Journal of Crystal Growth. - Royal Inst Technol, Dept Chem Engn & Technol, KTH, S-10044 Stockholm, Sweden. : Elsevier BV. - 0022-0248 .- 1873-5002. ; 296:2, s. 213-220
-
Tidskriftsartikel (refereegranskat)abstract
- Crystal growth of beta-FeF3 • 3H(2)O has been investigated in mixtures of 3 mol kg(-1) hydrofluoric acid and 3 mol kg(-1) nitric acid at 30, 40 and 50 degrees C. Seeded isothermal desupersaturation experiments have been performed in the range: 1.3 < S < 3.6. Solution samples were analysed for total iron concentration with inductively coupled plasma atomic emission spectroscopy. The true supersaturation driving force was estimated by a proper speciation using the software SSPEC using appropriate stability constants. Growth rate parameters of the BCF surface diffusion growth rate equation and the empirical power-law equation have been estimated by fitting the supersaturation balance equation using a nonlinear optimization procedure. The results show that the growth rate is surface integration controlled. The growth rate at a supersaturation ratio of 2 was found to be 3.5 x 10(-12) m s(-1) at 30 degrees C, 7.4 x 10(-12) m s(-1) at 40 degrees C and 16 x 10(-12) m s(-1) at 50 degrees C. The activation energy of the rate constant of crystal growth was found to be 61 kJ mol(-1). .
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| 38. |
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| 39. |
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| 40. |
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| 41. |
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| 42. |
- Forsberg, Kerstin, 1979-
(författare)
-
Crystallization of Metal Fluoride Hydrates from Mixed Acid Solutions
- 2009
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this work crystal growth and nucleation of b-FeF3×3H2O and crystallization of chromium (III), iron (III) and nickel (II) fluoride hydrates from mixed acid (1-3 mol/kg HNO3 and 1-6 mol/kg free HF) have been investigated. The solubility of b-FeF3×3H2O has been determined in solutions of different hydrofluoric acid (1-7mol/ kg) and nitric acid (0-7mol/ kg) concentrations at 30, 40 and 50°C. The total iron concentration at equilibrium ranges from about 1 to 35 g/kg solution. In the range of investigated conditions the solubility in terms of total iron content increases with increasing temperature and decreases with increasing concentration of hydrofluoric acid and nitric acid. The results are analysed by examining the chemical speciation in the solutions. The crystal growth kinetics of b-FeF3×3H2O crystals have been studied by performing seeded isothermal desupersaturation experiments in solutions of 1.5-3.0 mol/ kg nitric acid and 1.4- 5.6 mol/ kg free hydrofluoric acid at 30, 40 and 50°C. The results show that the crystal growth is surface integration controlled. When the driving force is based on a proper speciation no clear correlation of the growth rate with hydrofluoric acid or nitric acid concentration is found. The rate is about the same in industrial pickle liquor as in pure acid solutions. The growth rate at a supersaturation ratio (c(FeF3)free/cs(FeF3)free) of 2 was found to be 5.2×10-12m/s at 30°C, 7.9×10-12m/s at 40°C and 20×10-12m/s at 50°C. Thus, the crystal growth rate at 50°C is about four times higher than at 30°C. The temperature dependence of the rate constant corresponds to an activation energy of 55kJ/ mol. Crystallization from solutions supersaturated with both Cr(III) and Fe(III) has been investigated and it has been observed that Fe(III) and Cr(III) crystallizes in the form of Cr(Fe)F3×3H2O which is isostructural with CrF3×3H2O. Iron(III) and nickel(II) crystallizes into an unidentified fluoride hydrate crystal. The crystal growth rate of CrF3×3H2O at 50°C is about the same as the growth rate of b-FeF3×3H2O crystals.
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| 43. |
- Forsberg, Kerstin, et al.
(författare)
-
Crystallization of metal fluoride hydrates from mixed hydrofluoric and nitric acid solutions, Part I : Iron (III) and Chromium (III)
- 2010
-
Ingår i: Journal of Crystal Growth. - : Elsevier BV. - 0022-0248 .- 1873-5002. ; 312:16-17, s. 2351-2357
-
Tidskriftsartikel (refereegranskat)abstract
- Crystallization from hydrofluoric acid/nitric acid solutions supersaturated with Fe(III) and Cr(III) has been investigated. Iron and chromium crystallizes into a solid solution in the form of Cr(Fe)F-3 center dot 3H(2)O, which is isostructural with CrF3 center dot 3H(2)O and alpha-FeF3 center dot 3H(2)O. By seeded isothermal desupersaturation experiments, the growth rate of beta-FeF3 center dot 3H(2)O crystals at 50 degrees C has been studied in hydrofluoric acid and nitric acid solutions containing Cr(III). It is found that the growth rate of beta-FeF3 center dot 3H(2)O is essentially uninfluenced by the presence of 5 g/kg Cr(III). At 50 degrees C and a supersaturation ratio of 2 (c(FeF3)(free)/c(s)(FeF3)(free)), the growth rate is (0.8-2.2) x 10(-11) m/s in 3 mol/(kg solution) HFfree and 3 mol/(kg solution) HNO3.
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| 44. |
- Forsberg, Kerstin, et al.
(författare)
-
Crystallization of metal fluoride hydrates from mixed hydrofluoric and nitric acid solutions, part II : Iron (III) and nickel (II)
- 2010
-
Ingår i: Journal of Crystal Growth. - : Elsevier BV. - 0022-0248 .- 1873-5002. ; 312:16-17, s. 2358-2362
-
Tidskriftsartikel (refereegranskat)abstract
- Crystallization of nickel fluoride hydrate from mixed pickle acid and the influence of Ni(II) on growth rate of beta-FeF3 center dot 3H(2)O have been studied. Iron and nickel crystallize into an unidentified Fe/Ni fluoride hydrate crystal having the overall mol ratio of Ni, Fe, and F equal to 1:2:8, which is in accordance with the number of fluoride ions needed to balance the positive charges of Ni and Fe. The most probable empirical formula of this material is (FeF3)(2)NiF2(H2O)(6-10). By seeded isothermal desupersaturation experiments, growth rate of beta-FeF3 center dot 3H(2)O crystals at 50 degrees C has been studied in a hydrofluoric acid and nitric acid solution containing Ni(II). It is found that the growth rate of beta-FeF3 center dot 3H(2)O is essentially uninfluenced by the presence of 4 g/kg Ni(II).
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| 45. |
- Forsberg, Kerstin, et al.
(författare)
-
Extensible use of RDF in a business context
- 2000
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Ingår i: Computer Networks. - 1389-1286 .- 1872-7069. ; 33:1, s. 347-364
-
Tidskriftsartikel (refereegranskat)abstract
- The next generation of intranets should facilitate the structuring of information as well as the organizing of communication in networking organizations. For many organizations, one step in that direction is to structure information by adding metadata. We have encountered problems when applying Dublin Core, a metadata element set developed for discovery of existing information resources on the public Internet, on an extensive intranet. Our conclusion, argued in this paper, is that these problems are a consequence of trying to describe information resources without taking into account the context in which end users create and consume information. The next generation of intranets calls for a more contextual approach. The contribution of this paper is such an approach. We propose a framework including: (1) A model for describing three different areas of resources: business, information and communication, and integrating the resources description areas by means of generic classes, constrains and relations. (2) An extension to the model describing and integrating nodes and relations in networking organizations. (3) An extension to the model describing and organizing the communication of information in the business. The framework suggests an extensible use of RDF (Resource Description Framework) in a business context.
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| 46. |
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| 47. |
- Forsberg, Kerstin M., et al.
(författare)
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The influence of hydrofluoric acid and nitric acid on the growth kinetics of iron(III) fluoride trihydrate
- 2015
-
Ingår i: Journal of Crystal Growth. - : Elsevier BV. - 0022-0248 .- 1873-5002. ; 423, s. 16-21
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Tidskriftsartikel (refereegranskat)abstract
- The influence of hydrofluoric acid and nitric acid concentration on the growth rate of beta-FeF3 center dot 3H(2)O crystals has been studied in different hydrofluoric acid (4.7-10.7 mol/(kg H2O)) and nitric acid (2.1-4.6 mol/(kg H2O)) mixtures at 50 degrees C. Seeded desupersaturation experiments were performed and the results were evaluated by considering the chemical speciation using two different speciation programs. The growth rate at 50 degrees C at a supersaturation ratio of 2, expressed in terms of free FeF3, was found to be in the range of (0.4-3.8) x 10(-11) m/s. The growth rate order was found to be two or higher in all experiments. The low growth rate and high growth rate order indicate that the growth rate is governed by the surface integration step. The growth rate was found to be independent of variations in acid concentrations: this is in accordance with the assumption of a surface integration controlled growth rate.
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| 49. |
- Forsberg, Kerstin, 1960
(författare)
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Mobile Newsmaking
- 2001
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The research reported in this thesis concerns the design of new and innovative IT support for mobile news journalism. News journalists often have to report events on topics that they do not know very well and with little time for preparation. News reporting is often conducted in the field, away from the stationary IT support. The scope of this research is limited to the early phase of newsmaking when journalists transform everyday occurrences and happenings into newsworthy stories, discuss news events and formulate news tasks, do background research and frame news stories. The research question addressed is: How to provide reporters with contextual information relevant for news tasks in mobile situations? Contextual information reminds the reporter of the context for the task at hand. Helps the reporter to ask relevant and interesting questions and to properly frame the news story. The thesis contains field studies, design implications and applications of mobile technologies. The following theoretical and practical results are described: 1) NewsSpace, a design model describing new ways of using IT in news journalism, 2) NewsMate, a prototype of an IT service for mobile reporters, 3) FieldWise, a generalised architecture for mobile knowledge management, 4) A description of the newsmaking process focusing on the early phase of articulation and contextualisation of news tasks, and 5) A news task structure, called Localising News, and proposals of how the utilisation of task structures could improve the IT support for mobile news journalism.
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