Nanocellulose is a sustainable material and has shown interesting properties in various applications. One such application is Pickering emulsion, where the nanocellulose stabilizes the oil and water interface. Thus, this project aimed to evaluate a new type of nanocellulose, cellulose oxalate (COX), derived from different sources, dissolving pulp and bark, as a potential emulsifier. The properties of the nanocellulose, such as the chemical composition, morphology, aspect ratio, viscosity, and surface tension, are analyzed to determine how it affects the Pickering emulsion. Pectin has reported having emulsifying properties. Therefore, pectin derived from the bark was also studied as a potential emulsifier.  The emulsion capacity and emulsion stability of the Pickering emulsion were estimated. Additionally, the emulsions were observed and visualized in an optical microscope, and it showed that all Pickering emulsions were successful. The COX and pectin particles were successfully adsorbed at the interface to form individual droplets which were stable enough not to coalescence. With the images from AFM, the aspect ratio and morphology of the particles were measured. COX pulp had an average width of 5.5 nm and an average length of 372 nm. COX bark had an average width of 3.9 nm and an average length of 257 nm. Notably, COX pulp does have a slightly higher aspect ratio than COX bark. DLS was another way the particle size was measured. However, it was not a suitable technique because both COX did indicate a relatively polydisperse system and are therefore not suitable to be measured by DLS. Furthermore, the viscosity of the COX pulp and COX bark suspensions were measured with an Ubbelohde capillary viscometer which was not an ideal method because the COX suspensions were too thick and gel-like for the instrument and got clogged constantly. As expected, the surface tension decreased steadily, more so for COX pulp than COX bark with increasing concentration. Then again, this means that COX has a hydrophobic property that does reduce the surface tension of water. Lastly, the carbohydrate analysis did indicate that both COX do have a high amount of glucose. Moreover, both COX did also show a significant amount of other components.  Overall, this study does conclude that COX pulp, COX bark, and pectin did stabilize the Pickering emulsion to some degree, despite being inconsistent and can therefore be considered effective emulsifiers. / Nanocellulosa är ett hållbart material som har visat intressanta egenskaper i olika applikationer. En specifik applikation är Pickering emulsion, där nanocellulosan stabiliserar gränsytan mellan olje-och vatten fasen. Därav var syftet med detta projekt att utvärdera en ny typ av nanocellulosa, cellulosaoxalat (COX) producerad från olika källor såsom förhandlad pappersmassa och bark som ett potentiellt emulgeringsmedel. De olika egenskaperna hos nanocellulosan dvs. den kemiska sammansättningen, morfologin, partikelstorlek, viskositet och ytspänning undersöktes för att bestämma hur de påverkar Pickering emulsionen. Pektin har också rapporterats att ha emulgerande egenskaper. Därför studerades även pektin producerad från bark som ett potentiellt emulgeringsmedel.  Emulsionskapaciteten och emulsionsstabiliteten hos Pickering emulsionen uppskattades. Dessutom observerades och visualiserades emulsionerna i ett optiskt mikroskop som visade att alla Pickering emulsioner var successiva. Det innebär att COX- och pektinpartiklarna adsorberades successivt vid gränsytan för att bilda individuella droppar som var stabila nog att inte koalescensera. Med hjälp av bilderna från AFM mättes storleken på partiklarna och dess morfologi bestämdes. COX-massa hade en genomsnittlig bredd på 5,5 nm en medellängd på 372 nm. COX-bark hade en genomsnittlig bredd på 3,9 nm och en medellängd på 257 nm. Från resultatet, kan det noteras att COX-massa har något större partikelstorlek är COX-bark. DLS var ett annat sätt att mäta partikelstorleken. Dock, var det inte en lämplig teknik eftersom både COX-massa och COX-bark visade ett relativt polydisperst system och är därav inte lämplig att mättas i DLS. Vidare så mättes viskositeten för COX-massa och COX-bark med en Ubbelohde kapillärviskometer, vilket inte heller var en idealisk metod att mäta med eftersom COX lösningen var för tjock och gel-liknande och täppte till instrumentet. Däremot, som förväntad minskades ytspänningen stadigt med ökande koncentration. Detta var mer tydligt hos COX- massa än COX-bark. Oavsett så betyder det att COX har en hydrofob egenskap som minskar ytspänningen hos vatten. Sist men inte minst så indikerade kemiska sammansättningsanalysen att båda COX har en stor mängd glukos. De har även en betydande mängd av andra komponenter.  Sammantaget drar denna studie slutsatsen att COX-massa, COX-bark och pektin stabiliserade Pickering emulsionen till en viss del relativt väl, trots att det var inkonsekvent så anses de vara effektiva emulsionsmedel.

<i>Sclerotinia minor</i> Jagger is a fungal pathogen of cultivated peanut (<i>Arachis hypogaea</i> L.) that can cause crop losses in excess of 50%. Fungicides are not completely effective at controlling the disease and can cost up to $311 per hectare for three applications. The ability to produce oxalic acid is necessary for the pathogenicity of some <i>Sclerotinia</i> spp. With little to no naturally occurring resistance to Sclerotinia blight in <i>Arachis</i> spp., a biotechnological approach was used to confer resistance to the disease. Peanut plants were transformed with a gene from barley encoding oxalate oxidase, an enzyme that degrades oxalic acid. Transformed peanuts showed resistance to S. minor and increased yields under disease pressure compared to the parental lines. Before the resistant varieties can be marketed, they must be reviewed and approved by the governmental regulatory system. Responsibility for regulation of transgenic plants in the U.S. is shared among the U.S. Department of Agriculture (USDA) through the Animal and Plant Health Inspection Service (APHIS), the Food and Drug Administration (FDA), and the Environmental Protection Agency (EPA). These agencies require several different data sets including molecular characterization and field studies before each transformation event can be commercialized. This project was designed to characterize three different transformation events, N70, P39 and W171. Molecular characterization included determination of insertion number, copy number, intactness of the expression cassette and stable inheritance of the transgene. N70 was found to have two insertions and two copies while W171 had one insertion with one copy. The P39 event has two insertions and two or more copies. Each of the three events was stable over multiple generations. Phenotypic comparisons of each transgenic line to the parent cultivar were carried out in field studies. Characteristics such as oxalate oxidase expression, yield and quality, hay quality, disease occurrence, aflatoxin content and plant height were assessed. Transgenic peanuts showed few differences from the parent cultivar other than resistance to Sclerotinia blight and yield under disease pressure. Outcrossing studies were completed to determine the rate and distance of cross pollination. Outcrossing rates in N70, P39 and W171 were less than 2.5% and occurred up to 19 rows or 17.4 m from the nearest transgenic row. The molecular characterization and field performance of N70, P39 and W171 have been assembled into a document to petition APHIS for determination of non-regulated status. / Master of Science in Life Sciences

No / One of the major roles lichens play in shaping the natural world, both physically and biologically, is as agents in soil development: formerly considered only in a geological context, recent research has shown that they are capable of biodeteriorating stone substrata within a relatively short timescale. Chemical alteration of the substratum is achieved by the disruptive action of many species, particularly those capable of producing an oxalate at the thallus–substratum interface . The oxalate contributes significantly to the bulk and composition of the thallus itself and persists as an obvious encrustation after the lichen’s death. In the past, these disfiguring oxalate residues on ancient monuments have been variously interpreted as resulting from former mechanical/chemical renovation treatments, atmospheric pollution , and climatic weathering. The origin and nature of oxalate accretions, the factors involved in pedogenesis , and the development of lichen mosaics are reviewed. Aesthetic disfigurement versus physical damage to stonework is considered, and various aspects of stonework conservation are discussed.

Ce travail réalisé dans le cadre de l’initiative africaine de l’IUCr porte sur l’étude structurale par diffraction des rayons X de quelques architectures élaborées par association, via des interactions faibles, des anions {[M(C2O4)3]3-,M = Cr, Fe} et des cations complexes à base de la 2-picolylamine (amp) métaux de transition (Co2+, Cu2+ et Mn2+). L’architecture à base de l’ion Co2+ est bidimensionnelle et présente des feuillets ondulés constitués de chaines bimétalliques de chiralité différente où les deux ions complexes ([Cr(C2O4)3]3- et [Co(amp)3]3+ ) sont connectés par des liaisons hydrogène. Ces feuillets hébergent des molécules d’eau qui forment des clusters dodécamèriques aux caractéristiques nouvelles. Le composé déshydraté se réhydrate rapidement dans l’air ambiant et les deux états possèdent des couleurs différentes. Plusieurs cycles de déshydratation-réhydratation n’altèrent pas la qualité cristalline du composé. L’architecture à base des ions Cu2+ possède également des feuillets mais présente une ondulation plus forte que celle de l’architecture au cobalt. Ces couches sont constituées de chaines formées de cations dimériques [Cu2(amp)4Cl]3+ et d’anions {[M(C2O4)3]3-,M = Cr, Fe}. Les deux composés sont iso-structuraux et leur architecture présente des canaux monodimensionnels qui contiennent des molécules d’eau qui forment des clusters hexamèriques. Le composé subit des transitions de phase entre la basse température (100K) et la température de déshydratation (341K) avec une perte de la symétrie. Le composé se réhydrate plus difficilement que celui à base de l’ion cobalt(III). L’ion Mn2+ ne donne pas l’architecture escomptée mais un polymère de coordination nouveau / This work, realized under the IUCr initiative, framework involves the structural study via X-ray diffraction, of some heteromolecular architectures formed by the association through non-covalent bonds, between the tris (oxalato) chromate (III) and tris (oxalato) ferrate (III) anions {[M(C2O4)3]3-, M = Cr, Fe} and the cationic complex of the 2-picolylamine (amp) and transition metal (Co2 +, Cu2 + and Mn2 +). Co2 + ion builds two-dimensional corrugated layers made of bimetallic chiral chains where the two different complex ions ([Cr(C2O4)3]3- and [Co(amp)3]3 +) are connected by hydrogen bonds. These layers, connected by weak hydrogen interactions, host between them, water molecules which build dodecameric clusters having new characteristics. The dehydrated compound has different structure and color and is able to quickly reabsorb water molecules from surrounding to regenerate the initial compound despite that it has no pores. Several cycles of this process do not seriously affect the crystalline quality of this compound. The compound obtained with the Cu2 + ion also has a two-dimensional framework. Their layers are formed between the dimeric cation [Cu2 (amp) 4Cl]3 + and the anion {[M(C2O4)3]3-,M = Cr, Fe}. Both compounds are iso-structural; their frameworks are formed via π - - - π interactions and build 1D channels which contain water molecules forming hexameric clusters. The compound undergoes a phase transition between 100 K and the dehydration temperature (341K). During this dehydration, a loss of symmetry of the compound is recorded and rehydration process is more difficult than for cobalt(III)-framework. The use of Mn2+ ions does not give the expected architecture but a new coordination polymer

Afin de suivre de manière continue l'évolution de réactions photochimiques de composés solides, un appareillage d'ATG a été muni d'un dispositif optique permettant l'irradiation UV-visible des échantillons, <i>in situ</i>. Des études sont possibles dans les mêmes conditions d'appareillage avec ou sans lumière, sous diverses longueurs d'onde et intensités, dans des conditions de pression et de température désirées. Les résultats de l'étude expérimentale de l'oxalate et du carbonate d'argent ont permis d'approfondir la compréhension de leur mécanisme de décomposition avec ou sans irradiation. L'appareillage mis au point constitue également un nouveau type de réacteur adapté à des études de dégradation ou de vieillissement de solide à la lumière.

La nanostructuration de la matière parauto-assemblage est actuellement un des domaines de recherche fondamentale les plus dynamiques et ouvre de vastes perspectives technologiques. Cette thèse se propose d'étudier l'auto-assemblage de nanocristaux d'oxalate de cuivre. Ce composé peut être considéré comme système modèle dont les propriétés permettent une transposition à l'élaboration de nanostructures complexes. Une étude bibliographique portant d'une part sur le phénomène d'auto-assemblage à l'échelle mésoscopique, d'autre part sur le cas particulier des oxalates de métaux divalents constitue la première partie de ce travail. Puis, la caractérisation structurale des nanocristaux d'oxalate de cuivre et l'influence des conditions de synthèse sur leur auto-assemblage permettent d'aboutir à un modèle de mésocristaux issus d'une orientation des nanocristaux par reconnaissance de faces cristallines. Enfin, les modifications morphologiques des mésocristaux en présence d'additifs et l'étude spectroscopique de ces nanostructures confirment le modèle proposé par la mise en évidence d'une adsorption sélective des additifs sur certaines faces des nanocristaux.

Un certain nombre de réactions de décomposition des solides de la forme : S1 &#8594 S2 + &#124G&#124 présentent un grand intérêt pratique. On peut citer la préparation des liants hydrauliques obtenus par déshydratation des hydrates salins. Ces réactions constituent aussi un procédé courant d'obtention de catalyseurs de synthèse pour la chimie industrielle : Les oxydes métalliques en particulier peuvent être obtenus par cette voie à partir des sels du métal (carbonates - hydroxydes - formiates, etc, ...). Malgré l'intérêt pratique de ces réactions leur mécanisme est souvent mal connu. L'hétérogénéité du système est responsable de cette méconnaissance car elle rend délicate les mesures dans la zone réactionnelle et ne permet pas toujours de maîtriser l'ensemble des paramètres qui influent sur la réaction. La plupart des études fondamentales consacrées aux réactions de ce type ont pour but de décrire l'évolution géométrique de l'interface réactionnel ou d'interpréter par des lois formelles les courbes d'évolution en fonction du temps. Nous avons cherché dans ce mémoire à progresser dans le sens d'une meilleure connaissance des processus chimiques qui affectent les réactions de décomposition des solides.

The pre-analytical phase is known for being the most important step in the laboratory process to reach reliable test results. If handling, transport or preparation of the sample is performed incorrectly the results can deviate from the true value. Today, sampling tubes contains various additives to stabilize concentration levels. The aim of this study was to test a new sampling tube containing fluoride/citrate for glucose, lactate and homocysteine. It was also of interest to evaluate the stability of those three analytes in lithium-heparin, sodium-fluoride/potassium oxalate and fluoride/citrate tubes. To perform the sustainability study, a method verification was done for homocysteine in plasma. The study was performed in a hospital laboratory on the routine instrument Roche Cobas 6000 analyzer. Blood was drawn from 20 patients and was analyzed at the hospital laboratory in Gävle. The blood samples were transported frozen to the laboratory in Hudiksvall and were used in the method verification. For the sustainability study, blood was drawn from 10 healthy volunteers in lithium-heparin, sodium-fluoride/potassium oxalate and fluoride/citrate tubes. The method verification was approved. The results showed that glucose was stable for up to 72 hours in Vacuette Glycaemia tube with fluoride/citrate and this tube also gave more accurate results. Lactate and homocysteine were also stable in fluoride/citrate, but needs further studies. All three analytes were more stable if the sample tubes were centrifuged as soon as possible after blood collection. Fluoride/citrate tubes were stable without centrifugation directly.

The order of OH groups in the crystal structure of SbC2O4OH, a potential precursor in the synthesis of ternary oxides, was debated. Neutron diffraction on the deuteride SbC2O4OD revealed disordered OD groups with half occupation for deuterium atoms on either side of a mirror plane (SbC2O4OD at T = 298(1) K: Pnma, a = 582.07(3) pm, b = 1128.73(5) pm, c = 631.26(4) pm). O–H stretching frequencies are shifted by a factor of 1.35 from 3390 cm−1 in the hydride to 2513 cm−1 in the deuteride as seen in infrared spectra. SbC2O4OH suffers radiation damage in a synchrotron beam, which leaves a dark amorphous residue. Thermal decomposition at 564 K yields antimony oxide, carbon dioxide, carbon oxide, and water in an endothermic reaction. When using SbC2O4OH as a precursor in reactions, however, ternary oxides are only formed at much higher temperatures.

Under de senaste åren, på grund av överanvändningen av icke förnybara resurser har den ekologiska miljön på jorden påverkats allvarligt. I takt med detta ökade oron bland människor om att resurserna skulle ta slut. Därför är det nödvändigt att utveckla och använda mer miljövänliga förnybara resurser. Ett av dessa alternativ är cellulosabaserat material, vilket är ett utmärkt val. Vanligtvis består cellulosabaserat material av ett förstärkande material (cellulosafiber) och en matris (polymer eller metall). Dock bör kompatibiliteten mellan cellulosamaterialet och polymermatrisen ses över, eftersom generellt är kompatibiliteten mellan de låg. I detta projekt studerades olika metoder för att förbättra kompatibiliteten mellan cellulosamaterialet och polymermatrisen. Två cellulosamaterial (mikrokristallin cellulosa (MCC) och cellulosaoxalat (COX)) behandlades med olika modifieringsmetoder för att förbättra kompatibiliteten och gränssnittsinteraktionen mellan materialen. För att modifiera MCC och COX användes bland annat kulmalning, vatten som dispergeringsmedel, förestring av cellulosafibrerna med oljesyra under olika reaktionstider (6, 18, respektive 48 timmar), samt att tillsätta ett kompatibiliseringsmedel, maleinsyraanhydrid-ympad polypropylen (MAPP), i olika halter (1% respektive 2%). För att framställa kompositproverna användes extrudering och formsprutning. Dragprovning genomfördes för att testa de mekaniska egenskaperna hos proverna. Ytterligare karakteriseringsanalyser som utfördes på de olika cellulosapulvren var kontaktvinkeln (CA), svepelektronmikroskopi (SEM), infrarödspektroskopi (FTIR), och röntgendiffraktion (XRD). Resultatet från dragprovningen visade att COX-proverna med 1% MAPP som kompatibilisator gav den högsta draghållfastheten och Youngs modul av alla kompositproverna som producerades i detta exjobb. Användningen av MAPP som kompatibiliseringsmedel visade ett bättre resultat än de andra undersökta metoderna för att förbättra kompatibiliteten mellan den hydrofila ytan på MCC/COX och den hydrofoba ytan på polymermatrisen. Att använda MAPP som kompatibilisator bör prioriteras vid tillverkningen av kompositmaterial. / In recent years, with the excessive use of non-renewable resources on the earth, the ecological environment has been seriously affected. At the same time, humans began to worry about running out of resources. Therefore, it is necessary to develop environmentally friendly renewable resources. Cellulose-based material is an excellent choice. Commonly, cellulose-based material consists of reinforcement (cellulose fiber) and matrix (polymer or metal). However, the compatibility between cellulosic material and polymer matrix should be considered. In general, the compatibility between them is poor. In this project, several methods to improve the compatibility between the cellulose material and polymer matrix were studied. Two cellulosic materials (microcrystalline cellulose (MCC) and cellulose oxalate (COX)) were treated with different modification methods to improve the compatibility and interfacial interaction between the cellulosic material and polymer matrix. Ball milling, using water as a dispersing agent, using oleic acid to esterify cellulose fiber for different reaction times (6 h, 18 h, and 48 h), and using different concentrations (1% and 2%) of maleic anhydride grafted polypropylene (MAPP) as compatibilizers were applied to improve the compatibility between cellulose fiber and polymer matrix.  To produce the composite specimens, extrusion and injection molding were utilized. Tensile testing was done to test the mechanical properties of the specimens. Contact angle (CA), scanning electron microscope (SEM), Fourier Infrared Spectrometer (FTIR), X-ray diffraction (XRD) were also performed on the various cellulose powders as characterization methods. According to the result of tensile testing, COX samples with 1% MAPP as compatibilizer, showed the highest tensile strength and Young’s modulus of all the composite samples produced in this master thesis. Using MAPP as a compatibilizer shows a better result than using other methods to improve the compatibility between hydrophilic MCC/COX surface and hydrophobic PP matrix. The use of MAPP as a compatibilizer should be prioritized when producing composite materials.