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Abstract The phosphorous‐based flame retardant additives poly(m‐phenylene methylphosphonate) (PMP) and resorcinol bis(diphenyl phosphate) (RDP) are reacted with bisphenol F and aniline–based benzoxazine (BF‐a). DSC, rheological analysis, FT‐IR, and soxhlet extraction reveal the covalent incorporation of both FR additives—initiating phenols in PMP structure as well as free phenols generated via transesterification reaction in the case of RDP. In contrast to PMP, RDP elongates the processing window but decreases the thermo–mechanical properties. Both additives increase the resistance in reactions against small flames with solely a phosphorous loading of 0.3 wt%, resulting in a V‐0 rating and an improvement in the OI value by up to 2% for RDP and 4% for PMP. Both FRs reduce the heat release rate but increase the smoke production and the smoke toxicity in the case of RDP.

This work explores the challenges of using life cycle assessment (LCA) and life cycle cost (LCC) analysis to provide easily accessible decision support for early product development in cases where intellectual property (IP) and privacy issues require special consideration. Innovation research projects with partners representing different links along the value chain are potential examples of such cases. A case study in which spreadsheet-based cradle to compounder's gate LCA and LCC screening tools were created for candidate flame retarded polymer formulations exemplifies the need for better solutions to overcome problems associated with lack of transparency due to IP/privacy concerns. These problems affect data quality, scaling up processes, and uncertainty of the results. The consortium in this case study had a common overall goal, although each of the partners had a unique perspective on the polymer development process and different IP/privacy needs. The measures used to overcome the challenges include aggregation, normalisation, and omission of costs and impacts common to all candidate compounds. The resulting LCA and LCC screening tools represent a compromise between providing the requested information at the level of detail required by the partners and reporting results that are as accurate and useful as possible. The findings are: in cases where absolute secrecy must be maintained, no one can learn which materials and processes provide the optimal results; appointing a trusted third party to handle sensitive inventory data can cause increased uncertainty of the results due to lack of peer review; the results of the work cannot be built upon by subsequent research.

Artikeln beskriver svensklärares interaktion och samstämmighet i samtal om summativ bedömning av gymnasieelevers skrivande. I ett dialogiskt perspektiv (Linell, 2011) undersöks interaktionella mönster avseende dominans, dynamik och koherens i tre svensklärargruppers bedömningssamtal. Dessa interaktionella mönster ställs i relation till uttryck för samstämmighet inom och mellan lärargrupperna. Resultatet visar att lärarna uttrycker hög grad av samstämmighet i bedömningssamtalen men att de bedömningar som lärarna gör enskilt i anslutning till samtalen enbart till viss del överensstämmer med gruppens beslut. Lägst grad av samstämmighet uppvisar den lärargrupp som i samtalen framstod som mest samstämmig. Där kännetecknas beslutsprocesserna av låg intensitet genom att få alternativ till bedömningar prövas. I de lärargrupper där intensiteten är högre genom att flera lärare styr samtalet i olika riktningar och där lärarna tillsammans prövar flera olika förslag på bedömning överensstämmer även enskilda lärares bedömningar i högre grad med gruppens beslut. Bedömningsöverensstämmelsen mellan lärargrupperna är däremot låg.

Bisphenol F and aniline-based benzoxazine monomers were selected to fabricate basalt, glass and carbon fiber reinforced polybenzoxazine via vacuum infusion, respectively. The impacts of the type of fiber reinforcement on the resulting material properties of the fiber reinforced polymers (FRPs) were studied. FRPs exhibited a homogenous morphology with completely impregnated fibers and near-zero porosity. Carbon fiber reinforced polybenzoxazine showed the highest specific mechanical properties because of its low density and high modulus and strength. However, regarding the flammability, fire, smoke and toxicity properties, glass and basalt reinforced polybenzoxazine outperformed carbon fiber reinforced polybenzoxazine. This work offers a deeper understanding of how different types of fiber reinforcement affect polybenzoxazine-based FRPs and provides access to FRPs with inherently good fire, smoke and toxicity performance without the need for further flame retardant additives.

One way to support the development of new safety practices in testing and field failure situations of electric vehicles and their lithium-ion (Li-ion) traction batteries is to conduct studies simulating plausible incident scenarios. This paper focuses on risks and hazards associated with venting of gaseous species formed by thermal decomposition reactions of the electrolyte and electrode materials during thermal runaway of the cell. A test set-up for qualitative and quantitative measurements of both major and minor gas species in the vented emissions from Li-ion batteries is described. The objective of the study is to measure gas emissions in the absence of flames, since gassing can occur without subsequent fire. Test results regarding gas emission rates, total gas emission volumes, and amounts of hydrogen fluoride (HF) and CO2 formed in inert atmosphere when heating lithium iron phosphate (LFP) and lithium nickel-manganese-cobalt (NMC) dioxide/lithium manganese oxide (LMO) spinel cell stacks are presented and discussed. Important test findings include the large difference in total gas emissions from NMC/LMO cells compared to LFP, 780 L kg−1 battery cells, and 42 L kg−1 battery cells, respectively. However, there was no significant difference in the total amount of HF formed for both cell types, suggesting that LFP releases higher concentrations of HF than NMC/LMO cells.

The work involves fabrication of natural fibre/Elium® composites using resin infusion technique. The jute fabrics were treated using phosphorus-carbon based flame retardant (FR) agent, a phosphonate solution and graphene nano-platelet (GnP), followed by resin infusion, to produce FR and graphene-based composites. The properties of these composites were compared with those of the Control (jute fabric/Elium®). As obtained from the cone calorimeter and Fourier transform infrared spectroscopy, the peak heat release rate reduced significantly after the FR and GnP treatments of fabrics whereas total smoke release and quantity of carbon monoxide increased with the incorporation of FR. The addition of GnP had almost no effect on carbon monoxide and carbon dioxide yield. Dynamic mechanical analysis demonstrated that coating jute fabrics with GnP particles led to an enhanced glass transition temperature by 14%. Scanning electron microscopy showed fibre pull-out locations in the tensile fracture surface of the laminates after incorporation of both fillers, which resulted in reduced tensile properties.

I studien samtalar tre lärargrupper om elevers skrivande och skrivundervisning i ämnet svenska på gymnasiet. Det teoretiska perspektiv som läggs på dessa samtal är didaktiskt och inriktas på hur lärare formulerar och använder bedömningsinformation om elevers skrivande för beslut om skrivundervisningens innehåll. Resultatet visar att lärares bedömningar av elevers skrivande behandlar fler och delvis andra aspekter av skrivförmåga än vad deras didaktiska beslut sedan omfattar. De kvalitetsuppfattningar och förväntningsnormer som lärarna uttrycker i sina bedömningar av elevers skrivande inriktas huvudsakligen på texters kommunikativa kvaliteter, den stilistiska utformningen och textuppbyggnaden, följt av ämnesinnehåll och källanvändning. De didaktiska beslut som fattas utifrån bedömningen av elevers texter inriktas däremot i stort sett enbart på att eleverna behöver skrivundervisning i att disponera text och att använda källor. Detta gör att överensstämmelsen är låg mellan lärarnas beslut om skrivundervisningens inriktning och deras förväntningar på vad eleverna ska kunna. De didaktiska besluten omfattar i begränsad utsträckning den bedömningsinformation som lärarna själva har formulerat. Nyckelord: Skrivbedömning, kvalitetsuppfattningar, förväntningsnormer, didaktiska beslut, formativ bedömning, svenskämnets didaktik, svenska på gymnasiet Abstract This article presents an analysis of teacher group discussions about students’ writing in the subject of Swedish in upper secondary school. The study adopts a pedagogical perspective on these discussions and focuses on examining teachers’ expressed assessment criteria and relating them to their pedagogical decision-making. The results reveal that the teachers’ assessments of students’ writing focus on much more, and partly other, criteria than their pedagogical decisions. The quality standards that teachers express in the discussions about students’ texts focus mostly on communicative quality, language style and text structure followed by content and the use of sources. The pedagogical decisions are, on the other hand, almost exclusively focusing on text structure and the use of sources. This means that there is a gap between the teachers’ perceptions of qualities in students’ writing and their pedagogical decisions. The pedagogical decisions cover to a limited extent the assessment information that teachers themselves formulated. Keywords: Writing assessment, assessment criteria, pedagogical decision-making, formative assessment, Swedish in upper secondary school

The quality of clinical teaching in Swedish medical schools has recently been questioned by student representatives at the medical schools in Sweden. The clinical teaching at Uppsala University Medical School has previously only been sparsely evaluated and with varying instruments. Our aim was to develop a simple assessment instrument and implement it uniformly, enabling cross comparisons between different departments. Further we wanted to investigate students’ response rate and analyze their response pattern.A questionnaire inspired by a concept from Stanford University was created and introduced at hospital departments performing clinical teaching of medical students. Ten questions reflecting different aspects of clinical teaching were used. The outcome was used for specific feedback to the clinical teachers, cross comparison and official ranking of the departments.The evaluation instrument has been successfully developed and uniformly implemented throughout the departments of the hospital. The students have with a relatively high response rate graded the items with a great deal of variation between and within the clinical rotations. Altogether, this has provided specific feedback to the clinical teachers and enabled cross comparison between departments. Our belief is that the instrument also applies to other educations involving supervision.

Abstract  The mass of dioxins, PAH (polycyclic aromatic hydrocarbons) and VOC (volatile organic compounds) emitted from fires to the atmosphere in Sweden per year has been estimated. The estimate is based on the number of fires in buildings, vehicles, waste and forest fires in Sweden in 1999. It is estimated that the total emission of dioxins from fires is in the range 0.5–1.4 g TEQ. The total emissions of PAH and VOC are in the ranges 2–12 ton and 13–200 ton, respectively. The estimated emission of dioxins from fires approximately corresponds to the total emission from traffic or half the emissions from municipal waste combustion (Swedish data from 1993). The fire statistics show that the mass of material combusted in building fires during a year is approximately 7500 ton, while that from forest fires is 2600 ton. Additionally, 2000–3000 tons are combusted in vehicle fires, fires in containers, etc. In addition to the more common types of fires during a year, individual large incidents may contribute significantly to the total emission. Such incidents include fires in municipal landfills or specific waste storage facilities (such as those for used tyres). An assessment of the consequences of such incidents has been made. This assessment implies that a large contribution to the emission of dioxins could be expected from fires in landfills and from fires in waste plastics (PVC) and tyres. Fires in deposits of wood chips and tyres are also significant potential sources of PAH and VOC. [ABSTRACT FROM AUTHOR]

Detailed quantitative characterization of the combustion gases from a series of room fires is reported in this article. Three simulated room fires were conducted with a test room containing a typical domestic fuel load of furniture including a TV-set. Two types of TV-sets were studied in the experiments, i.e. those containing fire retarded and non-fire retarded enclosure material. The measurement of the combustion gases included inorganic species and various organic species among them polychlorinated and polybrominated dibenzodioxins and furans, and selected brominated flame retardant agents. The detailed quantitative characterization of the combustion gases from the room fires forms a unique source of emission data for fire incidents in buildings. Chlorinated dibenzodioxins and furans were found in the combustion gases from all room tests. No brominated dioxins were found, however brominated furans were found. Further, the results from the room tests indicate that a TV-set treated with brominated flame retardants included in the fire load of a room fire does not necessarily increase the emission of bromine containing organic combustion products. The methodology applied for the sampling and analysis has been described in Part I of this series of articles. [ABSTRACT FROM AUTHOR]

The results of detailed measurements of the emissions from simulated fires with TV-sets are presented in this article. Results from both small- and full-scale fire experiments with flame retarded and non-flame retarded TV-sets are discussed. The measurements cover a broad range of chemical species including specific fire retardant agents and both chlorinated- and brominated dibenzodioxins and furans. The results from similar measurements, but in this case from simulated room fires, can be found in part II in this series of articles.The methodology applied for the measurement of this large range of fire gases is presented in this article. Further, the sampling and analysis methods common for both the TV fires and the simulated room fires are described in detail in conjunction with the experimental results from the TV fires. Additionally, recommendations are made concerning good practice when conducting fire gas determinations of similar complexity. [ABSTRACT FROM AUTHOR]