Syftet med undersökningen är att belysa och exemplifiera hur NO-undervisningen kan bli mer elevcentrerad utan att tappa kunskapsinnehåll. Syftet har specificerats genom forskningsfrågan: Hur påverkar genomtänkta lärardemonstrationer i NO-undervisningen elevernas provresultat?   Undersökningsgruppen består av sex klasser i grundskolans högstadium. Klasser som på schemat har fysik (tryck) i årskurs 7 samt kemi (syror och baser) i årskurs 8. Undervisningen (interventionen) fokuserade lärardemonstrationer med elever som assistenter kombinerat med övertänkta diskussionsfrågor. Eventuell utveckling av kunskapsnivån skattades med kvantitativa mått på grundval av skriftliga prov före och efter undervisningen. Prov som bedömdes med ledning av de nationella provens A, C och E bedömningsmallar. En signifikant förbättring konstaterades (p <0,05 via t-test) mellan prestation på prov efter jämfört med före interventionen. Inga generella slutsatser dras men för den aktuella undersökningsgruppen antas den genomförda (teoretiskt grundade) interventionen öka elevernas motivation och bidra till ett mer elevaktivt klassrumsklimat.

Human bodies are in constant interaction with materials containing known and unknown chemicals of hazardous behavior. One group of chemicals are polycyclic aromatic compounds (PACs) which can be present in both indoor and outdoor materials, commonly in plastics. PACs are known for their cancerogenic behavior and thus should be considered and studied in an attempt to decrease human exposure. The following project reports the execution and results from chemical analysis of 48 PACs including parent polycyclic aromatic hydrocarbons (PAHs), alkylated PAHs and dibenzothiophenes (S-PAC), searched for in different materials commonly found indoors. Eleven samples were prepared and analyzed using GC/MS target analysis. 23 out of the 33 parent PAHs targeted were detected and quantified. In addition, 12 out of 15 alkylated PAHs including four dibenzothiophenes (S-PAC) were detectable in the samples. The contents of parent PAHs ranged from 105 ng/g to 6700 ng/g in the samples, with the highest value being present in a laminated artificial leather sample. The alkylated PAHs ranged from 34 ng/g to 3000 ng/g, and a recycled hard plastic contained the highest amount. Amongst the parent PAHs, the dominating compound in the samples was phenanthrene. For the alkylated PAHs, 2-methylnaphtalene was the compound present in the highest mass fraction. When comparing the samples, most similarities in PAC composition could be seen in the artificial leather samples excluding a high content of naphthalene in the laminated leather. The recycled plastic material consisted of the highest variety of PACs. The results presented that none of the samples exceeded the limit values set by EU regulation regarding eight PAHs (PAH8) in consumer products. However, poor recovery in addition to poor resolution of the majority of the high molecular mass compounds suggest further investigation of method optimization.

Det finns mycket forskning kring läroböckers upplägg, men inte ur ett elevperspektiv. Syftet med den här studien är därför att undersöka vem eleven är i ett kemididaktiskt perspektiv i relation till olika läroboksupplägg. Studien tar sin utgångspunkt från lärobokens multimodala utformning och metoden ”Motivationsstrategier för inlärning” som kan kopplas till bokens utformning, dess övningsuppgifter och extramaterial. Genom analys av läroböcker, enkätstudie med slutna och öppna frågor samt semistrukturerade intervjuer av gymnasieelever som läser naturvetenskapliga programmet karaktäriseras hur elever upplever olika läroboksupplägg. Resultatet visar att elever kan ha helt olika upplevelse av samma lärobok och främst saknar nivåindelade övningsuppgifter i läroböcker och extramaterial. Vad läraren tar med på proven avgör vilka delar av läroboken som eleverna prioriterar. Slutsatsen från studien är att ingen lärobok uppfyller alla elevers behov eftersom olika elever tolkar kemins förenkling av verkligheten via text och bild på olika sätt. Därför blir det viktigt att läraren kompenserar för lärobokens begränsningar genom att presentera samma fenomen med andra förklaringsmodeller.

Detta utvecklingsarbete har fokuserat på att undersöka elevers upplevelser av formativa bedömningsmatriser i undervisningen i kemi och att undersöka elevers upplevelser av att ge och få kamratrespons. Undersökningen har baserats på 25 elevers upplevelser av när de använt två olika sorters formativa analytiska bedömningsmatriser: en generell/uppgiftsnärabedömningsmatris som användes när de skrev laborationsrapport och gjorde kamratbedömning,och en uppgiftsspecifik som användes när de genomförde laborationsmomenten.Eleverna har besvarat frågeformulär där både öppna och stängda frågor formulerats. Svaren på dessa frågor har analyserats och kategoriserats utifrån frågeställningarna.Resultaten i detta utvecklingsarbete visar tydligt att eleverna upplevde att användning av de båda bedömningsmatriserna påverkade deras kunskapsutveckling positivt. Framför allt den uppgiftsspecifika formativa bedömningsmatrisen inte bara guidade dem under bedömningsmomentet, utan hjälpte dem också att formulera vad de skulle förbättra till nästa gång. Däremot var de mer tveksamma till hur de såg på kamratbedömning och så många som 1/3 tyckte att det var meningslöst. De upplevde att de lärde sig mer av att få feedback vid kamratbedömning än att ge feedback.

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Density Functional Theory is used in order to shed light on the reaction mechanisms and the origins of stereoselectivity in enantioselective organocatalytic reactions. The reactions investigated are the dipeptide-catalyzed aldol reaction, the cinchona thiourea-catalyzed nitroaldol reaction and the prolinol derivative-catalyzed hydrophosphination reaction. We can justify the stereoselectivity in the reactions from the energies arising from different interactions in the transition states. The major contributions to the energy differences are found to be hydrogen bond-type attractions and steric repulsions. This knowledge will be useful in the design of improved catalysts as well as general understanding of the basis of selection in other reactions. / QC 20101111

This thesis is divided into four parts with organic chromophores for dye sensitized solar cells as the common feature and an introduction with general concepts of the dye sensitized solar cells. The first part of the thesis describes the development of an efficient organic chromophore for dye sensitized solar cells. The chromophore consists of a triphenylamine moiety as an electron donor, a conjugated linker with a thiophene moiety and cyanoacrylic acid as an electron acceptor and anchoring group. During this work a strategy to obtain an efficient sensitizer was developed. Alternating the donor, linker or acceptor moieties independently, would give us the tool to tune the HOMO and LUMO energy levels of the chromophores. The following parts of this thesis regard this development strategy. The second part describes the contributions to the HOMO and LUMO energy levels when alternating the linker moiety. By varying the linker the HOMO and LUMO energy levels was indeed shifted. Unexpected effects of the solar cell performances when increasing the linker length were revealed, however. The third part describes the investigation of an alternative acceptor group, rhodanine-3-acetic acid, in combination with different linker lengths. The HOMO and LUMO energy level tuning was once again successfully shifted. The poor electronic coupling of the acceptor group to the semiconductor surface proved to be a problem for the overall efficiency of the solar cell, however. The fourth part describes the contributions from different donor groups to the HOMO and LUMO energy levels and has so far been the most successful in terms of reaching high efficiencies in the solar cell. A top overall efficiency of 7.1 % was achieved. / QC 20101108

Fuel shortage during the Second World War led to oil production in Kvarntorp, Kumla during 1942-1966 by pyrolyzing alum shale rich in pyrite, FeS2, and organic material such as kerogen. This production has led to a lot of waste laying deposited out in the open after the mining closed and has had negative environmental impact in the form of ongoing weathering and leaching of acidic water and leaching of trace elements into its surroundings. Chemical processes are still ongoing in this deposit, with temperatures reaching 700 °C on certain hotspots. Once the deposit cools down, precipitation will be able to enter the deposit and start leaching acidic water containing trace elements that will risk polluting groundwater in the surrounding areas. No one knows how many years it will take for the deposit to cool down, but it has been estimated to take at least 100 years.This study did leaching experiments on weathered fines as well as red ash in large columns while being oxygenated. Analyses consisted of ICP-MS, pH, electrical conductivity, acidity, alkalinity, and sulphate concentration.The results showed high concentrations of many valuable and potentially toxic elements in the leachates especially higher amounts of copper compared to previous studies.

In this master thesis project, the removal of micro-pollutants (MPs) from water and wastewater were investigated by ozonation and the peroxone process O3/H2O2. Themain aim of the study was to compare the degradation efficiency of the two processes for a selection of organic biocides and active pharmaceutical ingredients (APIs) in wastewater and synthetic water. Synthetic water and wastewater effluent were spiked with fifteen compounds including twelve biocides and three APIs and samples were taken at different time points to determine degradation kinetics in treatment by the two processes, respectively. Most of the biocides tested in this study showed moderately reactivity, or were non-reactive, with O3 (e.g., Carbendazim, 1H-Benzotriazole, 1, 2-Benzisothiazol-3(2H)-one, 2, 4-Dinitrophenol, 4-nitrophenol) and some of the biocides and APIs were readily reactive with ozone (O3) and were removed from the water by direct O3 oxidationduring both processes. Trimethoprim was found to be an ozone reactive micropollutants and showed highest reactivity with O3. In the abatement mechanism, these micro-pollutants are removed based on the ozone-based processes and with hydroxyl radical •OH in peroxone process. Comparing the two processes, the peroxone process showed highest percentage removal of compounds (90-100%) within moderate time periods (30 s - 2 min) in synthetic water and (30 s to 10 min) in wastewater. The results revealed that the peroxone process showed highest removal efficiency and with higher reproducibility. Further, generally