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Hydrogen fuel cells for the development of a sustainable society : A case study on opinions and pedagogics regarding hydrogen fuel cells in Sandviken / Vätebaserade bränsleceller för utveckling mot ett hållbart samhälleAldenholt, Robin January 2017 (has links)
Last couple of years’ vehicles propelled by electricity generated from a hydrogen fuel cell has emerged as an alternative to the fossil fuel vehicles, so that the greenhouse gas emissions causing climate change can decrease. In Sandviken, a collaboration between the municipality, Sandvik AB and AGA has resulted in a hydrogen refuelling station, only the fourth in Sweden. As the knowledge and awareness of hydrogen fuel cells is unknown Sandvik AB wants to investigate what the general opinion and knowledge is but more importantly, how can pedagogical theories be used to increase awareness and knowledge. The purpose of this thesis is therefore to examine what the population of Sandviken think of a development of a hydrogen society as well as climate change and the concept of sustainable development. Based on the found status of knowledge and awareness in these issues a couple of tools and actions are suggested on how to increase general knowledge and awareness, applicable both for schools and organisations outside school. The method used to fulfil the purpose was a survey that was sent out to people employed at Sandviken municipality and Sandvik AB. The survey results were analysed to see which factors correlate with a likelihood to support a hydrogen society development. That is used to see what approach to use when educating people about hydrogen and sustainable development. The results show that people in Sandviken were very positive about the hydrogen refuelling station, and the level of knowledge people had did not significantly affect how much support they showed. However, the people’s support for a hydrogen development is greatly affected by the fact that a refuelling station has been built. Therefore, the result that the level of hydrogen knowledge seems irrelevant should not be taken as a general fact true for all societies. When educating people about hydrogen one should put emphasis on raising awareness and knowledge in sustainable development and climate change, since that has a positive effect on the likelihood to support a hydrogen development. This could be done via a, in this report constructed, SSI case (socio-scientific issues) that can be adjusted to fit environments and occasions outside school. / De senaste åren har bilar framdrivna av elektricitet producerad av vätgasbränsleceller blivit ett alternativ till bilarna som drivs av fossila bränslen, så att växthusgasutsläppen som orsakar klimatförändringen kan minskas. I Sandviken har ett samarbete som involverar Sandvikens kommun, Sandvik AB och AGA resulterat i en tankstation för vätgas, endast den fjärde i Sverige. Eftersom kunskapsnivån och medvetenheten om vätgasbränsleceller är okänd vill Sandvik AB undersöka vad den generella åsikten och kunskapen om detta är men kanske ännu viktigare, hur man kan använda pedagogik-teorier för att öka kunskap och medvetenhet. Syftet med det här arbetet är därför att studera vad invånarna i Sandviken tycker om en utveckling av ett vätgassamhälle, liksom klimatförändring och konceptet hållbar utveckling. Baserat på den nuvarande statusen på kunskap och medvetenhet inom dessa ämnen kommer rapporten att föreslå ett antal verktyg och åtgärder som kan användas för att öka kunskap och medvetenhet, tillämpbara både i skolan och i organisationer utanför skolan. För att uppfylla det här syftet så skickades en enkät ut till anställda på Sandvikens kommun och Sandvik AB. Enkätresultaten analyserades för att utforska vilka faktorer som korrelerar med en sannolikhet att stödja en utveckling av ett vätgassamhälle, något som kan användas som en utgångspunkt när man utbildar människor om detta. Resultaten visar att människor i Sandviken var mycket positiva till vätgastankstationen och att nivån av kunskap om vätgas de har inte direkt påverkade hur mycket stöd de visade. Dock kan det faktum att en tankstation har byggts påverka hur mycket stöd vätgas har. Att kunskapsnivån om vätgas skulle vara irrelevant ska därför inte ses som ett generellt resultat applicerbart på alla samhällen. När man vill utbilda människor om vätgas så bör tonvikt läggas på att öka kunskap och medvetenhet för hållbar utveckling och klimatförändringen, eftersom dessa faktorer visade sig ge en positiv effekt på sannolikheten att stödja en utveckling av ett vätgassamhälle. Det kan göras genom att använda det SNI-fall (samhällsfrågor med naturvetenskapligt innehåll) som finns beskrivet i rapporten och som kan justeras för att passa miljöer och tillfällen utanför skolan
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The metal binding properties of kraft ligninWaltersson, Johanna January 2009 (has links)
<p>There is a strong driving force to increase the competitiveness of the pulping industry by finding new business opportunities. In this context full utilisation of the wood raw material used in conventional pulping mills is of vital importance. One focus area is to increase the utilisation areas of lignin. LignoBoost is a new method to obtain kraft lignin of high purity.</p><p>The aim of the project was to investigate and increase the ability of LignoBoost kraft lignins to bind metals in aqueous solutions.</p><p>The metal binding property of kraft lignins was evaluated using copper (II) ions. The metal binding capacities were 1.76 mg Cu<sup>2+</sup>/g LignoBoost softwood kraft lignin, 0.96 mg Cu<sup>2+</sup>/g LignoBoost hardwood kraft lignin and 1.12 mg Cu<sup>2+</sup>/g condensed softwood kraft lignin. The metal binding capacities of the softwood and hardwood kraft lignins from LignoBoost were lower than expected, when compared to the metal binding capacities of other lignins found in literature. The highest copper binding capacity of a kraft lignin found in literature was almost 50 times greater than that of the LignoBoost softwood kraft lignin.</p><p> </p><p>The Mannich reaction was used to increase the nitrogen content in softwood lignin, and thereby increase its electron-donating capacity. An increase in electron-donating capacity should promote its metal binding capacity.</p><p> </p><p>The Mannich reaction occurs in the vacant ortho position of the phenolic groups of lignin, introducing an aminomethyl group at that position. The only vacant ortho position in the phenol unit for reaction is in the guaicyl unit. Softwood lignin underwent a Mannich reaction, since softwood contains a greater number of guaiacyl units than hardwoods.</p><p> </p><p>A screening of the products from this Mannich reaction on LignoBoost softwood kraft lignin was performed to optimise the reaction conditions. The reaction time, temperature, amount of formaldehyde and dimethylamine were varied. The Mannich products were evaluated by elemental analysis. The conditions giving the highest nitrogen content in the product were used further in a Mannich reaction of condensed softwood kraft lignin. The condensed softwood kraft lignin (7 g) was treated with dimethylamine (0.35 mol) and formaldehyde (0.35 mol) at 80°C for 24 hours.</p><p> </p><p>The metal binding experiment could not be carried out with Mannich-modified condensed softwood kraft lignin since the lignin dissolved in the copper solution.</p><p> </p><p>When introducing nitrogen functionalities into lignin the electron-donating capacity should increase. An increase in donor groups should promote the metal binding capacity of the lignin. A problem that occurred when introducing aminomethyl groups was an increase in solubility of the lignin. Water solubility of the lignin derivative is undesirable in the envisaged utilization area, metal binding in, for example mine deposits, from where contaminated water may be a concentrated source of heavy metals.</p>
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The metal binding properties of kraft ligninWaltersson, Johanna January 2009 (has links)
There is a strong driving force to increase the competitiveness of the pulping industry by finding new business opportunities. In this context full utilisation of the wood raw material used in conventional pulping mills is of vital importance. One focus area is to increase the utilisation areas of lignin. LignoBoost is a new method to obtain kraft lignin of high purity. The aim of the project was to investigate and increase the ability of LignoBoost kraft lignins to bind metals in aqueous solutions. The metal binding property of kraft lignins was evaluated using copper (II) ions. The metal binding capacities were 1.76 mg Cu2+/g LignoBoost softwood kraft lignin, 0.96 mg Cu2+/g LignoBoost hardwood kraft lignin and 1.12 mg Cu2+/g condensed softwood kraft lignin. The metal binding capacities of the softwood and hardwood kraft lignins from LignoBoost were lower than expected, when compared to the metal binding capacities of other lignins found in literature. The highest copper binding capacity of a kraft lignin found in literature was almost 50 times greater than that of the LignoBoost softwood kraft lignin. The Mannich reaction was used to increase the nitrogen content in softwood lignin, and thereby increase its electron-donating capacity. An increase in electron-donating capacity should promote its metal binding capacity. The Mannich reaction occurs in the vacant ortho position of the phenolic groups of lignin, introducing an aminomethyl group at that position. The only vacant ortho position in the phenol unit for reaction is in the guaicyl unit. Softwood lignin underwent a Mannich reaction, since softwood contains a greater number of guaiacyl units than hardwoods. A screening of the products from this Mannich reaction on LignoBoost softwood kraft lignin was performed to optimise the reaction conditions. The reaction time, temperature, amount of formaldehyde and dimethylamine were varied. The Mannich products were evaluated by elemental analysis. The conditions giving the highest nitrogen content in the product were used further in a Mannich reaction of condensed softwood kraft lignin. The condensed softwood kraft lignin (7 g) was treated with dimethylamine (0.35 mol) and formaldehyde (0.35 mol) at 80°C for 24 hours. The metal binding experiment could not be carried out with Mannich-modified condensed softwood kraft lignin since the lignin dissolved in the copper solution. When introducing nitrogen functionalities into lignin the electron-donating capacity should increase. An increase in donor groups should promote the metal binding capacity of the lignin. A problem that occurred when introducing aminomethyl groups was an increase in solubility of the lignin. Water solubility of the lignin derivative is undesirable in the envisaged utilization area, metal binding in, for example mine deposits, from where contaminated water may be a concentrated source of heavy metals.
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Kemins betydelse för klimat och miljö : En kvalitativ studie av klimat- och miljöperspektiv i kemiundervisningen på gymnasiet och dess inverkan på elevernas intresse för kemiRosenius, Olle January 2020 (has links)
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Excited State Antiaromaticity Investigations of Pharmaceutically Relevant Heterocycles in Their Lowest ππ∗ and nπ∗ StateLyvik, Amanda January 2020 (has links)
No description available.
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Self-Diffusion and Microstructure of Some Ionic Liquids in Bulk and in ConfinementFilippov, Andrei January 2016 (has links)
An ionic liquid (IL) is a salt, which usually is in the liquid state at normal temperature and pressure. The properties of ILs can be adjusted for various processes and applications by choosing different combinations of ions. Similar to other salts, ILs contain only ions with positive (cations) and negative (anions) charges in equal proportions. However, to prevent solidification, ions in ionic liquids usually contain bulky organic chemical groups, which, apart from electrostatic interactions, promote other types of interactions between ions, such as: (i) van-der-Waals interactions; (ii) hydrogen bonding; (iii) - stacking, etc., depending on the particular chemical structure of the ions. All these interactions, in combination, may lead to formation of specific microstructures in ILs, which may vary with temperature caused by changing thermal rotational and translational energies of the ions. Ions in these microstructures may have preferential orientations relative to each other, maintain anisotropic properties similar to those in liquid crystals or, in some specific cases, may even separate into microscopically organised liquid phases. Therefore, the dynamics of ILs may also be dependent on their microstructure. In many practical applications ionic liquids are placed on surfaces or in confinements. Solid surfaces introduce extra forces, which may be specific to the charge of the ions or/and to functional groups in the ILs. The geometry and interactions of ions in confinements or/and pores of materials may also disrupt specific bulk microstructures of ILs. Both confinement effects and interactions of ions with surfaces are manifested in the translational dynamics of the ions. One of the most direct and informative methods to study translational dynamics of ILs is pulse-field-gradient nuclear magnetic resonance (PFG-NMR).In this thesis the results of PFG-NMR studies on a few classes of ILs are reported: (i) the historically “standard” (since Walden’s discovery in 1914) ionic liquid, the ethylammonium nitrate (EAN) and (ii) halogen-free orthoborate-based phosphonium, imidazolium and pyrrolidinium ILs with varied structure and lengths of alkyl chains in cations, and varied structures of orthoborate anions. These ILs were studied in bulk at different temperatures, and also in confinements, such as between parallel glass and Teflon plates and in mesoporous Vycor glass. It was found that diffusion coefficients of cations and anions in EAN, phosphonium and pyrrolidinium orthoborate ILs in bulk are different, but according to the standard Stocks-Einstein model, they correspond to diffusion of ions in homogeneous liquids. A change in the chemical structure of one of the ions results in a change in both the diffusion coefficient of the oppositely charged ion and the activation energy of diffusion for both ions in an IL. Similar effects were observed from the chemical shifts and diffusion coefficients measured by NMR for imidazolium orthoborate ILs dissolved in polyethylene glycol solutions, in which imidazolium cations strongly interact with PEG molecules, further affecting the diffusion of orthoborate anions via electrostatic interactions. A liquid-liquid phase separation was suggested for a few phosphonium and pyrrolidinium bis(mandelato)borate ILs, in which a divergence of diffusion coefficients and activation energies of diffusion for cations and anions was detected at temperatures below ca 50 °C. In addition, a free-volume theory was invoked to explain the dependences of density of ILs on the alkyl chain length in cations.It was also found that for a phosphonium bis(salicylato)borate IL confined in 4 nm mesoporous Vycor glass the diffusion coefficients of ions increase by a factor of 35! This phenomenon was explained by the dynamic heterogeneity of this IL in micropores and empty voids of the Vycor glass. For EAN IL in confinements between glass and Teflon plates, the diffusion of ethylammonium cations and nitrate anions is significantly anisotropic, i.e. slower in the direction of the normal to the plates and faster along the plates compared to diffusion of the ions in bulk. A plausible explanation of this PFG NMR data is that EAN forms layers near polar and non-polar solid surfaces. A similar phenomenon, to a lesser extent, was also observed for phosphonium cations of bis(mandelato)borate, bis(salicylato)borate and bis(oxalato)borate confined between glass plates. The results of these studies may have implications in modeling tribological performance, i.e., friction and wear reduction for contact pairs of different materials lubricated by various classes of ionic liquids. / För godkännande; 2016; 20160420 (andfil)
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Palladium-Catalyzed Synthesis and Transformation of OrganoboranesSebelius, Sara January 2006 (has links)
<p>This thesis presents the development of new palladium-catalyzed transformations involving synthesis and application of allylborane reagents. In these reactions various palladium sources, including pincer complexes and commonly used catalysts were applied.</p><p>A new transformation for allylation of aldehyde and imine substrates was devised using allyl acetates, diboronate reagents and catalytic amounts of Pd<sub>2</sub>(dba)<sub>3</sub>. By employment of commercially available chiral diboronates enantioenriched homoallyl alcohols could be obtained.</p><p>We have also developed a palladium-catalyzed method for synthesis of functionalized allylboronic acids from vinyl cyclopropane, vinyl aziridine, allyl acetate and allyl alcohol substrates using diboronic acid as reagent. In this process a highly selective selenium based pincer-complex was used as catalyst. The resulting allylboronic acid products were converted to potassium trifluoro(allyl)borates or allylboronates.</p><p>The functionalized allylboronic acids generated in the above procedure were employed as reagents in two synthetic transformations. One of these transformations involves a palladium(0)-catalyzed coupling reaction between allylboronic acids and aryl iodides. The reaction was regioselective for the branched allylic product, typically difficult to prepare in the absence of directing groups. We also developed another transformation for allylation of aldehydes with allyl alcohols via allylboronic acid intermediate. This procedure can be performed as a simple one-pot sequence affording homoallyl alcohols with excellent stereo- and regioselectivity.</p>
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How fining agents affect the tendency of pear base wine to form and stabilize foamDahlström, Karolina January 2010 (has links)
<p>The company Kiviks Musteri AB produces a pear base wine that forms stable foam, which is problematic from a production perspective. The aim of this thesis was to investigate the factors underlying foam stability in the pear base wine and to find means for its reduction. This was done by foam testing wines and varying several variables, such as the fining agents normally used in the wine production (bentonite, gelatin, siliceous earth and activated carbon), enzyme treatment, and by changing the fermenting yeast species.</p><p>Results: The wine started to form stable foam during fermentation, and foam stability could be reduced by using more bentonite and carbon during the fining process. The other fining agents appeared to have only limited impact on foaming characteristics. No pectin was present according to the pectin test, but protein bands were evident from SDS PAGE analysis, though absent in samples treated with increased doses of bentonite.</p><p>In conclusion, pectin is not a major foaming agent in the wine, the yeast is most likely the producer of the foaming agents, carbon and bentonite have a reducing effect on foam stability, bentonite also reduces protein content. Proteins are likely to be involved in the foam stabilization but are not the sole contributors to stable foam.</p>
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Foaming in Apple WineMårtensson, Ellinor January 2010 (has links)
<p>At Kiviks Musteri AB, situated in the southeast part of Scania, a wide variety of products based on fruits and berries, are produced. One of these products is base apple wine, which is used for the production of cider and mulled wine and also is sold to other producers of cider. A foaming problem has occurred at some customers when the cider is bottled, and this problem has been traced to the base wine. The aim of this paper is to investigate what causes the foaming and how the foaming is affected by the clarifying agents used during the production of the wine. An investigation whether silica based antifoaming agents might be a solution of the problem will be performed. During the work fermentations, clarification and foaming tests will be performed in laboratory scale in Kivik. Tests with four different silica based antifoaming compounds are carried out and on these samples the surface tension and viscosity are measured to see how these factors correlate with the foaming when antifoaming agents are added to the wine. What is more, fermentations with a new yeast type and fermentations with less fruit are made to investigate if this could give better foaming properties in the wine.</p><p>The tests showed that it is probably proteins that are the main cause of the foaming, but an increase of the amount of bentonite, the clarifying agent reducing protein content in the wine, is not possible since this causes too much sediment. Antifoaming agents gave reduced foaming times, which were at an acceptable level, but when the wine was mixed to cider base and filtered the effect was lost. No significant differences were observed between the four antifoaming compounds. The test with the new yeast type gave no positive results when it came to foaming. The test with less fruit showed a decrease in foaming but not sufficient enough.</p>
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Analys av vitamin B<sub>12</sub> i tillagad och återuppvärmd lax genom bioassay med <em>Lactobacillus delbrueckii</em> subart <em>lactis</em> <em>ATCC<sup>®</sup> 7830<sup>TM</sup></em>Edgren, Ellen January 2010 (has links)
<p>Halten näringsämnen i livsmedel varierar bland annat med tillagningsmetod, lagringstid och lagringsförhållanden, som exponering för ljus och syre. Oklarheter finns för mikrovågors inverkan på näringsämnen och framförallt på vitamin B<sub>12</sub>. Eftersom många äldre drabbas av brist på vitamin B<sub>12</sub>, är detta av intresse eftersom många hemmaboende äldre människor får hemleverans av färdiga matportioner som är avsedda att värmas, ofta i mikrovågsugn. Syftet med studien var att kunna ge en indikation på om uppvärmning genom mikrovågor påverkar halten vitamin B<sub>12</sub> i färdiga kylda måltider. Detta gjordes genom litteratursammanställning om vitamin B<sub>12</sub> och mikrovågar samt genom bioassay med <em>Lactobacillus delbrueckii</em>. Vitamin B<sub>12</sub> i ouppvärmd lax, lax värmd i mikrovågsugn samt lax värmd i konventionell ugn analyserades. Tillväxten av bakterier uppskattades genom mätning av turbiditet. Högst vitamin B<sub>12</sub>-halt sågs i mikrovågsvärmd lax, därefter ouppvärmd lax och ugnsvärmd lax. Statistiskt signifikanta skillnader sågs för analyserade vitamin B<sub>12</sub>-halter mellan ouppvärmt- och ugnsvärmt prov respektive mellan mikrovågsvärmt- och ugnsvärmt prov. De varierande vitaminhalterna kan bero på metodfel, otillräcklig vitaminextraktion eller att bakterierna inte konsumerat allt tillgängligt vitamin vid turbiditetsmätning. Slutsatsen av studien är att halten vitamin B<sub>12</sub> i livsmedel inte verkar påverkas negativt av mikrovågor, däremot finns tendenser att halten minskar beroende av temperatur och tillagningstid.</p>
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