The corrugated board is considered as the second most used packaging material and the world’s environmentally acceptable solution for packaging, with wide range of applications. After the manufacturing process, the corrugated board is cut into sheets and stored in a stack until optimum moisture content has been reached in order to avoid undesired properties. However, due to complex and various structures, it is difficult to estimate the appropriate time so to achieve the acceptable moisture level of the corrugated board stack. So a homogenized model of the stack has to be created which will have the same average properties as the real stack. In order to achieve this goal the behavior of a smaller part of the stack, the unit cell, is investigated. In the second step a homogenized model is created with the average transport of mass and heat. At the end, the unit cell is scaled up. In this master thesis, only the first and the second steps were simulated. This was achieved by creating a 3-D mathematical model using finite element method and simulating its properties in COMSOL Multiphysics®. Four mathematical models were used in the description of the 3-D model: the heat transfer, the moisture transfer, the vapour concentration and the gas pressure. Moreover, by applying the gradient in one direction in each case, the behavior of the detailed unit cell was investigated. Finally different simplified geometries were created and investigated so to approach a homogenized model which described better the average properties of the detailed model. By comparing the results of the models, it was concluded that the homogenized models 2 and 3 approached the values of the second detailed model but only inside of the unit cell. However, the deviation was not negligible and further investigation is required in order to find a new homogenized method.

Various distillates are treated with hydrogen gas during hydrotreatment in the presence of catalyst in order to reduce the sulfur and aromatic content of the product. Optimal hydrotreater performance is essential for producing Nynas specialty oils, in order to fulfill the planned production volume and to meet the product specification. Loss of catalyst activity is inevitable during the production. To adjust for the impact of catalyst deactivation, different process variables are manipulated. Different distillates affect the catalyst in different ways due to the variation in distillate composition. Distillates with higher organic nitrogen content and running at a lower temperature tend to deactivate the catalyst more due to the adsorption of nitrogen compounds on the active sites of the catalyst and their slow nature of desorption. In this master thesis, different catalyst deactivation mechanisms with a focus on nitrogen deactivation have been studied. Since nitrogen is not normally measured at Nynas, nitrogen content of different distillates and products and how these values change during operation was not known. Different distillates, blend of distillates and different products were measured to estimate roughly the typical nitrogen value of the distillates and products. The temperature data inside the reactors were analyzed to calculate and plot WABT (weighted average bed temperature) during different product runs and to see whether there is a correlation between the nitrogen content of the feed and operation severity (increase in WABT). Historical process data from hydrotreater unit 2 (mostly from 2013-2014) were analyzed with a view to finding out signs of catalyst deactivation. Similar product runs were also analyzed and compared to see how the catalysts performed at different periods of time. A kinetic model, based on HDS kinetics, has been used for following up two product runs. To do so, sulfur content of the feed and product were measured. Aromatic content of the product was also measured to see whether the product was on specification. .From the calculation and plotting of WABTs, it could be seen that there is an increase in WABT during the product runs operating at lower temperatures and with higher nitrogen content. From the comparison of two P3 product runs at two different time periods, it could be seen that ∆T development over one bed (amount of reaction over the bed) was much lower at one time. This can possibly be a sign of catalyst deactivation since it contributed to lesser amount of reaction over the bed. From the calculations by using the kinetic model, it could be seen that the actual temperatures were higher than the predicted temperatures. The increase in WABTs could also be noticed. These observations can possibly be coupled with nitrogen deactivation of the catalysts.  However, more tests are required to verify whether the temperature differences were significant or not. Other parameters which are also important from product selling point of view such as viscosity, color, flash point, acid number etc. and have not been covered in this degree project need to be taken into consideration before making further conclusions.

Syftet med vår studie var att ta reda på pedagogers erfarenheter och uppfattningar av litteraturen som redskap i undervisning av naturvetenskap i förskolan; i kombination med pedagogledda aktiviteter. Detta har vi gjort med hjälp av semistrukturerade intervjuer via de digitala plattformarna Zoom och Microsoft Teams. Totalt deltog tio respondenter i sex olika förskolor i Mellansverige. Vi har analyserat datamaterialet tematiskt med hjälp av de sex stegen i Braun och Clarkes (2006) analysmodell. Vidare har vi analyserat respondenternas svar utifrån sociokulturellt perspektiv genom Vygotskijs teori. Vårt resultat visar att pedagogerna anser att barn lär sig naturvetenskap genom praktiska aktiviteter med hjälp av sinnena, samtliga respondenter lyfter att litteraturen ses som en introduktion till ett tema eller aktivitet, ett hjälpmedel, introduktion och ett komplement till den praktiska aktiviteten som skapar ett intresse hos barnen till att bland annat utföra experiment. Litteratur kan även bidra till ökad förståelse med kombinationen text och bild. Pedagogerna lyfter få begränsningar med litteratur i undervisning av naturvetenskap. Faktaboken ses som för avancerad för barnen och kan behöva förenklas av pedagogen, möjligheten med faktaboken är att den breddar både barnens och pedagogernas kunskap. Den skönlitterära bilderbokens begränsning är dess fiktiva innehåll. Möjligheterna med den skönlitterära bilderboken är att den ses som mer barnanpassad utifrån barnens nivå. Begränsningar med att arbeta med fysikaliska fenomen och kemiska processer genom litteratur är att pedagogerna anser att det är något som framför allt måste upplevas. Då det kan vara svårt för barnen att förstå utifrån en bok i kontrast till djur och natur som anses lättare att läsa om. Möjligheterna med fysikaliska fenomen och kemiska processer genom litteratur anses vara som inspiration till experiment. Den digitala litteraturen ses som mer tillgänglig än den fysiska litteraturen för att den finns till hands i stunden när barnen intresserar sig för något, biblioteket ses som en resurs för att få tag på litteratur inom naturvetenskap. Det framkommer också att naturvetenskapen går att finna i de flesta barnböcker så länge pedagogen använder de naturvetenskapliga glasögonen. Slutsatsen är att litteratur kan användas för att få sammanhang och bli en del i det mångsidiga lärandet tillsammans med den praktiska aktiviteten och boksamtalet. / <p>Betyg i Ladok 210606.</p>

Peptide drugs are used to treat a broad spectrum of diseases such as cancer and HIV and have many more promising applications, such as new vaccines against SARS-CoV-2. The most popular manufacturing method for peptides is solid-phase peptide synthesis (SPPS). The main drawback of SPPS is that it is a costly and wasteful process.  SpinChem is a company that provides technology solutions for chemical processes. Recently, SpinChem has started investigating if their Rotating Bed Reactor (RBR) is suitable for peptide synthesis. The goal of this project is to investigate how the RBR can make processes like SPPS more resource-efficient. The idea is that the RBR-system can maximize the solid-phase to liquid ratio (STL). The STL is the ratio of the volume of solid-phase material and the volume of liquid. By maximizing the STL, it is possible to manufacture peptides using less solvents and chemicals. The main quest of the project is formulated into a single question:  How does a high STL affect the efficiency of the RBR-system?  To answer the question, Minitab's statistical software and design of experiments (DOE) will be used to plan and perform experiments in both lab- and industrial scales. DOE factorial experiments are used to gain as much information as possible about the new RBR-system. The results are analyzed and summarized to make a solid foundation for the continued work on the new RBR application.  Peptide synthesis efficiency in the RBR-system is measured using ionic adsorption. The ionic adsorption rate is measured in both lab-scale and industrial-scale experiments. In the lab-scale experiments, the decrease of ions was on average 86,5% after just 15 s with an average STL of 0,936. The industrial-scale experiments showed a similar result where the average decrease in ions was 92,9% after 20 s with an average STL of 0,947. It was concluded that the RBR-system can reduce the consumption of washing-solvent in SPPS by up to 82%.

Studiens syfte är att skildra hur förskollärare ser på sin roll i att stötta barnens språkutveckling i samband med lärandet om kemiska processer. Undersökningarna genomfördes med hjälp av pedagoger som arbetade på förskolor i fem kommuner i Mellansverige. I studien har en kvalitativ och en kvantitativ metod använts i form av enkäter och intervjuer. Enkäternas del i studien var att få en bred förståelse inom vilka kemiska processer som genomförs i förskolan. Intervjuerna genomfördes för att fördjupa studien inom de områden som framkom från enkäterna. Detta för att sedan ha möjligheten att diskutera och analysera resultatet kopplat till studiens frågeställningar och syfte. Resultaten åskådliggör att pedagogerna anser att de har en viktig roll i kemiska processer och har stor betydelse för utvecklingen av barnens vokabulär. Genom att vara aktiv som pedagog i en kemiaktivitet stimuleras barns språkutveckling då pedagogen kan tillföra fler begrepp vid den kemiska processen. Pedagogerna var också eniga om att aktiva och närvarande pedagoger stimulerar språkutvecklingen hos barnen i alla aktiviteter i förskoleverksamheten. I studien uppenbarades även att pedagogerna tycker att det är viktigt att benämna det som sker med rätt begrepp i aktiviteterna, redan med de allra yngsta barnen. / The purpose of the study is to describe how preschool teachers view their role of supporting children in their language development, in connection with learning of chemical processes. The study was conducted with the help of educators who worked at preschools in five municipalities in Central Sweden. In the study, a qualitative and a quantitative method was used in the form of questionnaires and interviews. The questionnaires part in the study was to gain a broad understanding of which chemical processes are carried out in preschool. The interviews were conducted to deepen the study in these areas that emerged from the questionnaires. This is to then have the opportunity to discuss and analyze the results linked to the study's questions and purpose. The results illustrate that educators believe that they have an important role in chemical processes and are of great importance for the development of children's vocabulary. By being active as an educator in a chemistry activity, children's language development is stimulated as the educator can add more concepts to the chemical process. The educators also agreed that active and present educators stimulate the language development of the children in all activities in the preschool activities. The study also revealed that the educators think it is important to name what happens with the right concept in the activities, already with the very young children.

Syftet med denna studie är att bidra med kunskapen om vilken innebörd läroplansbegreppet ”enkla kemiska processer” fått i förskolans naturvetenskapliga undervisning. Empirin samlades in genom kvalitativa semistrukturerade intervjuer av förskolepersonal, fördelat på sex förskollärare och fyra barnskötare. Resultatet visade att förskolepersonalen främst betonade undervisning om kemiska processer i syfte att förbereda barnen för framtida skolgång och ge positiva känslor för ämnet. Förskolepersonalen kopplade begreppet ”enkla kemiska processer” med undervisningsaktiviteter som är associerade med vatten, bakning, bakpulver, färg samt naturen som redskap. Resultatet visade även att kemiundervisning sker både planerat och spontant i verksamheten, samt att förskolepersonalen anser att kemiundervisningen ska genomföras utifrån barnens intresse och nyfikenhet, där det ska ske på ett lustfyllt sätt tillsammans med medforskande pedagoger.  En slutsats av studien är att förskolepersonalen har många tankar om vad ”en enkel kemisk process” är och hur det undervisas i förskolan, men att kemiämnet inte prioriteras i den dagliga verksamheten och att anledningen bland annat är att ämnet anses svårt. / The purpose of this study was to contribute knowledge about the meaning of the curriculum concept ”simple chemical processes” in preschool science teaching. The data was collected through qualitative semistructured interviews with preschool staff, consisting of six preschool teachers and four childminders. The study showed that the preschool staff mainly emphasized the importance of teaching chemical processes as preparation for the children's future schooling and encouragement of a positive attitude towards the subject chemistry. The preschool staff linked the concept of ”simple chemical processes” with teaching activities involving water, baking powder, baking and paint. They also linked the concept to changes in the natural world. The results also showed that chemistry teaching took place in both a planned and spontaneous way, and that the preschool staff believed that chemistry teaching should be based on the children's interest and curiosity. They believed that it should be undertaken in a fun way together with other involved educators present. One conclusion of the study is that the preschool staff varied in their interpretation of "simple chemical processes" and how they were taught in preschool. Chemistry teaching was not given high priority, according to the preschool staff, one of the reasons being that the subject was considered difficult.

This thesis covers fundamental aspects of process control when growing titanium oxide nanoparticles in a reactive sputtering process. It covers the influence of oxygen containing gas on the oxidation state of the cathode from which the growth material is ejected, as well as its influence on the particles oxidation state and their nucleation. It was found that a low degree of reactive gases was necessary for nanoparticles of titanium to nucleate. When the oxygen gas was slightly increased, the nanoparticle yield and particle oxygen content increased. A further increase caused a decrease in particle yield which was attributed to a slight oxidation of the cathode. By varying the oxygen flow to the process, it was possible to control the oxygen content of the nanoparticles without fully oxidizing the cathode. Because oxygen containing gases such as residual water vapour has a profound influence on nanoparticle yield and composition, the deposition source was re-engineered to allow for cleaner and thus more stable synthesis conditions. The size of the nanoparticles has been controlled by two means. The first is to change electrical potentials around the growth zone, which allows for nanoparticle size control in the order of 25-75 nm. This size control does not influence the oxygen content of the nanoparticles. The second means of size control investigated was by increasing the pressure. By doing this, the particle size can be increased from 50 – 250 nm, however the oxygen content also increases with pressure. Different particle morphologies were found by changing the pressure. At low pressures, mostly spherical particles with weak facets were produced. As the pressure increased, the particles got a cubic shape. At higher pressures the cubic particles started to get a fractured surface. At the highest pressure investigated, the fractured surface became poly-crystalline, giving a cauliflower shaped morphology.

Syftet med den här studien var att undersöka en alternativ slamningsreducerande teknik till spolning, som effektivt kan ta bort biologisk påväxt. Ultraljud undersöktes som en möjlig metod för att ta bort igenslamningen från omvänd osmos med ett spirallindat membran. Tidigare forskning har föreslagit att ultraljud skulle kunna vara effektivt på platta membran men inte på spirallindade membran, på grund av packningsdensiteten som spirallindan medför. Därför genomfördes inom denna studie försök med spirallindade membran och ultraljud, för att få en förståelse av dess effekter inom det spirallindade membranet. För det första undersöktes tidsberoendet av ultraljud, vilket visade liknande resultat som tidigare forskning, att ultraljudet uppnådde effekt inom några minuter. För det andra behandlades två membran en gång om dagen under 12 dagar, med undantag för dag 6 och 7. Ett behandlades med ultraljud och ett med spolning, och den mikrobiologiska kontamineringen i permeatet analyserades sedan. Det ultraljudsbehandlade membranet producerade mindre kontaminering under de 12 dagarna. Det krävs dock fler experiment och analyser för att bekräfta detta, eftersom tidsbegränsningar inte möjliggjorde repetitioner. En ekonomisk utvärdering genomfördes också för att undersöka möjligheten att implementera ultraljud i kommersiell skala. Den ekonomiska aspekten är en avvägning mellan vattenkostnad och energikostnad, som är beroende av geografiskt läge. Överlag indikerar resultaten att det sparade vattnet kostar mer än den energi som krävs, vilket är fördelaktigt för implementering av ultraljudsbehandling. Sammanfattningsvis visade ultraljudsbehandlingen bättre resultat än spolning inom några minuter, och hade även en ekonomisk fördel, men kostnaden för energi till vatten är beroende av geografisk plats. / The purpose of this study was to investigate an alternative fouling mitigation technique to flushing, that can efficiently remove biological fouling. Ultrasound was investigated as a possible method of removing fouling from a reverse osmosis spiral wound membrane. Previous research had suggested ultrasound to be efficient on flat sheet membranes but not on spiral wound membranes, due to the packing density. Therefore, this study conducted experiments on spiral wound membranes with ultrasound, as to get an understanding of its effects within the spiral wound membrane. Firstly, the time dependency of ultrasound was investigated, and showed similar results to that of previous research, that the ultrasound was efficient within a matter of minutes. Secondly, two membranes were subject to treatment once a day over the span of 12 days, with an exception for days 6 and 7. One was treated with ultrasound and one with flushing, and the microbiological contamination in the permeate was then analysed. The ultrasonically treated membrane produced less contamination throughout the 12 days. However, more experiments and analysis would be required to confirm this, as time constraints did not allow for repetitions. An economic assessment was also performed, as to evaluate the feasibility implementing ultrasound on a commercial scale. This is a weigh-off between water cost and energy cost, which is dependent on geographical location. Overall, the results indicate that the water saved costs more than the energy required though, which is favourable for the implementation of ultrasonic treatment. To conclude, the ultrasonic treatment showed better results than flushing within a matter of minutes, and also economically had an advantage but the cost of energy to water is relative to geographical location.

This work focuses on the physical properties and crystallization of theophyline co-crystals. Co-crystals of theophylline with oxalic acid, glutaric acid and maleic acid have been investigated. The DSC curves of these co-crystals show that their first endothermic peaks are all lower than the melting temperature of theophylline. The decomposition temperature of theophylline – oxalic acid co-crystal is at about 230 °C, determined by DSC together with TGA. After decomposition, the remaining theophylline melts at about 279 °C, which is higher than the known melting temperature of theophylline, suggesting a structure difference, ie. a new polymorph may have been formed. The formation of hydrogen bonds in theophylline – oxalic acid co-crystal was investigated by FTIR. Changes of FTIR peaks around 3120 cm-1 reflects the hydrogen bond of basic N of theophylline and hydroxyl H of oxalic acid. The solubility of theophylline – oxalic acid co-crystal and theophylline – glutaric acid co-crystal was determined in 4:1 chlroform – methanol and in pure chloroform respectively. At equilibrium with the solid theophylline – oxalic acid co-crystal, the theophylline concentration is only 60 % of the corresponding value for the pure solid theophylline. At equilibrium with the solid theophylline – glutaric acid co-crystal, the theophylline concentration is at least 5 times higher than the corresponding value for the pure solid theophylline. Two phases of theophylline were found during the solubility determination. In the chloroform – methanol mixture (4:1 in volume ratio) the solubility of the stable polymorph of theophylline is found to be about 14 % lower than that of the metastable phase. Various aspects of the phase diagram of theophylline – oxalic acid co-crystal was explored. Theophylline – oxalic acid co-crystal has been successfully prepared via primary nucleation from a stoichiometric solution mixture of the two components in chloroform – methanol mixture. By slurry conversion crystallization, the co-crystal can be prepared in several solvents, and yield and productivity can be significantly increased. Theophylline – glutaric acid can be successfully prepared via both co-grinding of the two components and slow evaporation with seeding. / QC20100608

Studiens syfte är att bidra med kunskap om lärares uppfattningar kring barns erfarenheter och lärande om kemiska processer och möjligheten till progression i övergången mellan förskola och förskoleklass, enligt lärare i dessa två skolformer. Studien utgår ifrån en kvalitativ metod med stöd av semistrukturerade intervjuer där nio informanter deltagit i studien.  Resultatet visar att lärarna uppfattar naturvetenskap på två olika vis, naturvetenskap som en helhet och naturvetenskap som biologi. Studien pekar även på att det till viss del finns en otydlig kommunikation vid samverkan kring övergångar mellan förskola och förskoleklass. Slutligen visar studien att de förmågor och kunskaper som lärarna beskriver prioriteras i informationsutbytet mellan förskola och förskoleklass är det sociala samspelet, språket och barns intressen.  Slutsatsen är att förskollärare och förskoleklasslärare behöver mer kunskap inom naturvetenskap med fokus på kemikaliska processer och fenomen, men också insyn och kunskap om varandras arbete. Det blir utmanade för lärare att skapa möjlighet till progression i barns lärande om kemikaliska processer och fenomen i ett övergångsarbete om det inte finns medveten undervisning eller samsyn kopplat till ämnesområdet. / The purpose of the study is to contribute knowledge about teachers' perceptions of children's experiences and learning about chemical processes and the possibility of progression in the transition between preschool and preschool class, according to teachers in these two school forms. The study is based on a qualitative method supported by semi-structured interviews where nine informants participated in the study.  The results of the study show that the teachers perceive science in two different ways, science as a whole and science as biology. The study also points out that there is to some extent an unclear communication when collaborating on transitions between preschool and preschool class. Finally, the study shows that the abilities and knowledge that the teachers describe prioritized in the exchange of information between preschool and preschool class is social interactions, language and children's interests.  The conclusion is that preschool teachers and preschool class teachers need more knowledge in science with a focus on chemical processes and phenomena, but also insight and knowledge about each other's work. It will be challenging for teachers to create the opportunity for progression in children's learning about chemical processes and phenomena in a transition work if there is no conscious teaching or consensus linked to the subject area.