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1
Sta, Fabien. "Étude et modélisation de l'influence des propriétés physico-chimiques de suspensions concentrées sur leur comportement rhéologique." Thesis, Université de Lorraine, 2018. http://www.theses.fr/2018LORR0012/document.
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Les suspensions concentrées sont des fluides qui présentent des propriétés rhéologiques complexes. Ces propriétés sont modélisées par des équations structurelles qui considèrent à la fois les phases liquide et solide, mais avec un manque de lien avec les paramètres granulaires (en particulier la compacité des suspensions non modèles). L'objectif global de ce travail est d'étudier la dépendance de la viscosité de suspensions concentrées énergétiques aux propriétés physico-chimiques de leurs composants. Les propriétés ayant l'impact le plus significatif sur la viscosité sont choisies en utilisant la méthodologie des plans d’expériences. Le modèle résultant représente le diamètre médian D50 en volume de petites et grandes particules, la densité des grosses particules d, la surface spécifique des particules, la contrainte de cisaillement γ ̇ appliquée à la suspension, la viscosité du fluide de suspension ηf et une constante valeur pour la fraction volumique en solide φ≃0.51. De plus, ce modèle permet de prédire la viscosité des suspensions étudiées pour une fraction volumique en solide allant de 0 à 0,51 %<br>Concentrated suspensions are fluids which display complex rheological properties. These properties are modelled through structural equations which consider both the liquid and solid phases, but with a lack of consistency for the granular parameters (in particular the maximum packing fraction of non-model suspensions). The overall objective of this paper is to investigate the dependence of the viscosity of energetic concentrated suspensions on the physicochemical properties of their components. The properties with the most significant impact on the viscosity are chosen using the Design of Experiments methodology. The resulting model accounts for the mass median diameter D50 in small and large particles, the large particles density d, the specific surface area of small particles, the shear stress γ ̇ applied to the suspension, the viscosity of the suspending fluid η_f and a constant value for the volume fraction in solid ϕ≃0.51. Moreover, this model allows predicting the viscosity of the studied suspensions for a volume fraction in solid from 0 to 0.51 %
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Liao, Baoqiang. "Physicochemical studies of microbial flocs." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0024/NQ49831.pdf.
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Harris, Lee George. "Physicochemical lithography of functional nanolayers." Thesis, Durham University, 2006. http://etheses.dur.ac.uk/9358/.
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To further understand the biological interactions that govern our daily lives it is essential to develop new techniques for the robust tethering of immobilized bio-molecules to substrates for applications such as bio-mimicry, diagnostics, and durability as well as further self assembly. Current technologies devised for this purpose include the functionalization and lithography of Langmuir-Blodgett films, self-assembled monolayers and spin-coated layers. Whilst these methods provide suitable surfaces, they suffer from being substrate dependent and inappropriate for complex 3D-geometries, thus prohibiting their application to a wide range of materials. Pulsed plasma polymerised films can overcome this hurdle and are utilised in this thesis to present amine, epoxide, thiol and protein resistant Interfaces. For instance, genomic an-ays have been created via di-sulfide bridge formation between DNA and thiol groups. Whilst proteomic arrays have been fabricated either via electrostatic immobilization of proteins to charged regions surrounded by a protein resistant background, or alternately, covalent attachment to epoxide surface groups. Similarly, glycomic arrays have been produced by the covalent attachment of D-maltose and p-D-galacto-methanethiosulfonate to amine and thiol surface groups respectively. Furthermore, it has been shown that sequential plasmachemical nanolayering can provide a passivated upper layer and a reactive underlayer which can be subsequently exposed via mechanical removal of the top layer, to yield reactive pixels on the micron and nano-scale. Finally, the substrate independent nature of plasma polymers has been utilised for the coating of compact disc surfaces with reactive nanolayers. Subsequent protein immobilization has been accomplished via Inkjet printing and has shown promise for potential use as in point-of-care diagnostics.
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Mayes, Denise. "Physicochemical studies of phthalocyanine assemblies." Thesis, University of East Anglia, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.309909.
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The importance of the phthalocyanine molecule has generated interest in diverse fields such as thin films, polymer chemistry, liquid crystals, catalysts and numerable electrical, electronic and biological applications together with traditional applications such as dyes and pigments. These laboratories have, to date, concentrated on the synthesis of functionalised phthalocyanine moieties with properties which can be designed for specific applications and, as a result, a battery of materials has been produced at a rate that far exceeded the rate at which the compounds could be fully characterised. The work presented in this thesis is concerned with the study of a range of materials, already available in the group, with a view to providing information on the behavio L'r of Pcs in various molecular assemblies to develop them for specific applications. Chapter 2 is concerned with thin Pc films. The study concentrates on the thermotropic behaviour of some liquid crystalline Pes fonnulated as spin coated, Langmuir-Blodgett, smeared and sublimed films . Chapter 3 contains an account of photochemical stability studies carried out on a series of octaalkyl Pc both in solution and in the solid phase. The role of the central species, substituents and solvent (if applicable) is explored and the results of a series of experiments designed to probe the mechanistic features of the photochemistry are also presented. The development and characterisation of a series of zinc phthalocyanines as potential photosensitisers for use in the photodynamic therapy (PDT) of cancer is covered in chapter 4. The author has carried out photophysical measurements on some octaaJkyl zinc phthalocyanines and comparisons have been made, where appropriate, with other materials currently considered to be promising drug candidates for use in PDT. During the course of this research interesting aggregation and liquid crystal properties were observed for certain zinc and metal-free derivatives. Chapter 5 details how UVVis and IH-NMR. techniques were used to probe these intriguing effects a little further.
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Blake, S. M. "Physicochemical studies on sodium hyaluronate." Thesis, University of Salford, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381670.
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Gambrill, Martin Peter. "Physicochemical treatment of tropical wastewater." Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.237255.
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Dick, Lindsay J. "Physicochemical aspects of gene delivery." Thesis, University of Strathclyde, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.401581.
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Falcone, Pin Bruno Nicolás. "Physicochemical properties of inhalation drugs." Thesis, University of Cambridge, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.648175.
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Sousa, Felipe Domingos de. "Physicochemical properties of plant hemicelluloses." Universidade Federal do CearÃ, 2014. http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=12378.
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CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior<br>In this work six galactomannans (Adenanthera pavonina, Caesalpinia pulcherrima, Delonix regia, Dimorphera mollis, Prosopis glandulosa, Schizolobium parahyba) and three xyloglucans (Hymenaea courbaril, Mucuna sloanei e Tamarindus indica) were isolated from seed endosperm and cotyledon, respectively, by aqueous extraction followed by precipitation with ethanol. Yield of extraction, monosaccharide ratio, macromolecular parameters as well as molar mass distribution were determined and compared to guar gum (Cyamopsis tetragonoloba), LBG (Ceratonia siliqua) and xanthan (Xanthomonas campestris). Extraction yield in relation to seed mass ranged from 7.0 to 40.63%, with xyloglucan yields higher than the galactomannans ones. Schizolobium parahyba and Caesalpinia pulcherrima galactomannans presented the lowest protein content of 0.05% e 0.08%, respectively. The Mw values ranged from 0.09 â 3.37 x107 g mol-1 Flow curves of hemicelluloses solutions at 1% (w:v) were measured by varying the shear rate from 0.1 to 100 s-1. The resulting data were fit to the Power law e Herschel-Bulkley models. All the hemicelluloses presented shear-thinning behavior. Galactomannan and xyloglucans with different monosaccharide ratio showed similar consistency index; it may be influenced of the galactose distribution pattern on the chains and the interactions among the polysaccharides molecules. Rheological properties were compared and the results suggest new hemicelluloses sources which offer more profound applications in areas such as materials science, medicine e biology.<br>As hemiceluloses sÃo polissacarÃdeos presentes na parede celular de vegetais, onde funcionam como polissacarÃdeos de reserva e possuem uma cadeia principal composta por ligaÃÃes β-(1→4) em configuraÃÃo equatorial. Neste trabalho, hemiceluloses de sementes foram avaliadas quanto as suas propriedades reolÃgicas. Como resultado, galactomananas endospÃrmicas de Adenanthera pavonina, Caesalpinia pulcherrima, Delonix regia, Dimorphera mollis, Prosopis glandulosa e Schizolobium parahyba e xiloglucanas cotiledonÃrias de Hymenaea courbaril, Mucuna sloanei e Tamarindus indica foram isoladas por extraÃÃo aquosa, seguida por precipitaÃÃo em etanol. O rendimento das extraÃÃes, razÃo monossacarÃdica, parÃmetros macromoleculares, assim como distribuiÃÃo de massa molar foram determinados e comparados Ãs jà comercializadas goma guar (Cyamopsis tetragonoloba), LBG (Ceratonia siliqua) e goma xantana (Xanthomonas campestris). O rendimento das extraÃÃes em relaÃÃo à massa das sementes mostrou um intervalo de 7,0 a 40,63%, com os maiores valores para as xiloglucanas. Galactomananas de Schizolobium parahyba e Caesalpinia pulcherrima apresentaram os menores percentuais de proteÃnas, 0,05% e 0,08%, respectivamente. Valores de Mw variaram dentro de um intervalo entre 0,09 â 3,37 x107 g mol-1. Curvas de fluxo das soluÃÃes de hemiceluloses a 1% (m:v) foram obtidas pela variaÃÃo da taxa de cisalhamento entre 0,1 a 100 s-1. Os dados obtidos foram analisados pelos modelos de Lei das PotÃncias e Hershel-Bulkley demonstrando carÃter pseudoplÃstico para todas as hemiceluloses estudadas nessa concentraÃÃo. Galactomananas e xiloglucanas com diferentes razÃes monossacarÃdicas apresentaram Ãndice de consistÃncia similar, provavelmente influenciado pelo padrÃo de distribuiÃÃo de galactose nas cadeias e as interaÃÃes entre as molÃculas desses polissacarÃdeos. As propriedades reolÃgicas foram comparadas e os resultados sugerem novas fontes de hemiceluloses que permitem mais aplicaÃÃes em Ãreas como ciÃncia dos materiais, medicina e biologia.
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McGill, Robert Andrew. "Physicochemical measurements by gas chromatography." Thesis, University of Surrey, 1988. http://epubs.surrey.ac.uk/847792/.
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First the method of gas-liquid chromatography (GLC) has been used to obtain partition coefficients, K, at infinite dilution on polymeric and non-polymeric phases. About 30-40 solutes were studied per stationary phase. Secondly the method of gas-solid chromatography has been used to obtain adsorption isotherms for a series of adsorbents by the technique of elution by characteristic point (ECP). A single injection of a gas or vapour suffices to obtain the isotherm, and then the limiting Henry's law constant, Kh, for adsorption at low surface coverage. About 20-30 solutes were studied per adsorbent. Experiments were carried out at several levels of relative humidity (RH) 0%, 31% and 53%. The solute compounds used were chosen so as to have a wide range of properties such as polarity (pi*2), hydrogen-bond acidity (alpha[H]2), and hydrogen-bond basicity (beta[H]2). The results as log partition coefficients or -log Henry's constants were analysed by multiple linear regression analysis using equations such as: -LogK[H] or LogK = SPo + s.pi* 2 + a.alpha[H]2 + b.beta[H]2 + 1. LogL[18] where L[18] is the solute Ostwald absorption coefficient on n-hexadecane. In this way, the selectivity of the liquid polymeric phase or solid adsorbent towards classes of compound was investigated and equations for the prediction of further values of LogK or LogK[H] formulated. In parallel with the measurement of partition coefficients on liquid polymeric phases by GLC in this work, partition coefficients for the polymers have been determined using surface acoustic wave (SAW) devices by coworkers at the Naval Research Laboratory, Washington. The results for a series of 8-9 solutes in six polymeric phases show that partition coefficients and patterns of responses predicted through GLC experiments are the same as those found experimentally using coated SAW devices. Hence GLC can be used to evaluate possible coating materials, and by the technique of multiple linear regression analysis, to predict SAW responses for a multitude of vapours.
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Morimoto, Daichi. "Novel physicochemical properties of polyubiquitin chains." 京都大学 (Kyoto University), 2015. http://hdl.handle.net/2433/199328.
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Wangsa-Wirawan, Norbertus Djajasantosa. "Physicochemical properties of protein inclusion bodies." Title page, contents and introduction only, 1999. http://web4.library.adelaide.edu.au/theses/09PH/09phw2465.pdf.
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Bibliography: leaves 182-198. Improvements in the current production system of inclusion bodies and the downstream processing sequence are essential to maintain a competitive advantage in the market place. Optimisation of fermentation is considered to improve production yield; then flotation as a possible inclusion body recovery method.
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Teng, Ba-Bie. "Metabolic and physicochemical bases of hyperapobetalipoproteinemia." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=74368.
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The goal of this thesis was to elucidate the physicochemical and metabolic bases of Hyperapobetalipoproteinemia (HyperapoB). This disorder, which is likely the commonest metabolic abnormality associated with premature coronary artery disease, was defined as a combination of a normal, or near-normal, LDL cholesterol in the face of an elevated LDL apoB.<br>LDL, even in normals, is heterogeneous. The experimental findings herein confirm this. They also extend this concept to indicate that familial hypercholesterolemia (FH) and HyperapoB each imprint LDL in different and characteristic ways, each an exaggeration of the typical relations between LDL composition and size in normals. At one extreme is HyperapoB, which is characterized by most of the LDL particles being smaller and denser than normal because they contain less cholesteryl ester but the same amount of apoB as normal. At the other is FH, which is characterized by larger, cholesteryl ester-enriched particles. There is, as well, a predictable relation between LDL particle size and the immunoreactivity of certain apoB epitopes.<br>Turnover studies of hepatic apoB using traditional analytic models showed that hepatic apoB is overproduced in HyperapoB, a finding which stands in marked contrast to the impaired catabolism of apoB in FH. A new multi-compartmental model of LDL metabolism has been developed which appears to elucidate several of the basic mechanisms involved in the pathogenesis of HyperapoB. All the data to date indicate that the characteristic abnormalities of LDL in HyperapoB are all consequences of the overproduction of hepatic apoB. Obviously, the goal for future research must be to understand the basis for this overproduction. A preliminary study with adipose tissue suggested that the overproduction of hepatic apoB might be secondary to a defect in peripheral tissue triglyceride biosynthesis.
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Dale, Sara E. "Physicochemical processes at oil/water interfaces." Thesis, University of Warwick, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.487805.
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Pathomrungsiyounggul, Pattavara. "Physicochemical Properties of Calcium-fortified soymilk." Thesis, University of Reading, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.518215.
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Trainor, D. M. "Physicochemical characterisation of cystic fibrosis sputum." Thesis, Queen's University Belfast, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.398172.
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Ingram-Jones, Victoria Jane. "A physicochemical investigation of transition aluminas." Thesis, University of Exeter, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.307319.
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Lansita, Janice A. (Janice Ann) 1975. "Physicochemical characterization of immortal strand DNA." Thesis, Massachusetts Institute of Technology, 2004. http://hdl.handle.net/1721.1/18038.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Biological Engineering Division, 2004.<br>Includes bibliographical references.<br>Adult tissue differentiation involves the generation of distinct cell types from adult stem cells (ASCs). Current understanding of tissue differentiation mechanisms is based on studies of protein and RNAs that asymmetrically segregate between daughter cells during embryogenesis. Whether or not other types of biomolecules segregate asymmetrically has not been widely studied. In 1975, John Cairns proposed that ASCs preferentially segregate the oldest parental template DNA strands to themselves and pass on newly replicated DNA strands to their differentiating progeny in order to protect the stem cell from inheriting DNA replication mutations. This laboratory has shown non-random chromosome segregation in murine fetal fibroblasts that model asymmetric self-renewal like ASCs. In these cells, chromosomes that contain the oldest DNA strands co-segregate to the cycling daughter stem-like cells, while chromosomes with more recently replicated DNA segregate to the non-stem cell daughters. Previously, cytological methods were reported to elucidate non-random segregation in these cells. This dissertation research provides additional confirmation of the mechanism using physicochemical methods. Specifically, buoyant density-shift experiments in equilibrium CsCl density gradients were used to detect co-segregated "immortal DNA strands" based on incorporation of the thymidine base analogue bromodeoxyuridine. In addition, DNA from cells undergoing non-random mitotic chromosome segregation was analyzed for unique DNA base modifications and global structural modifications (by HPLC and melting temperature analyses). To date, these studies show no significant differences compared to control randomly segregated DNA. Components of the mitotic chromosome separation<br>(cont.) apparatus that might play a role in the co-segregation mechanism were also evaluated. Two homologous proteins, essential for proper chromosome segregation and cytokinesis, Aurora A kinase and Aurora B kinase, were highly reduced in expression in cells retaining immortal DNA strands and may indicate a role for them in the immortal strand mechanism. These studies independently confirm the immortal strand mechanism and provide methods for its detection in other cell lines. In addition, observed changes in chromosome segregation proteins that are potential candidates for involvement in the mechanism have revealed a new area of investigation in the laboratory. These findings are relevant to understanding normal tissue development, cancer, and aging.<br>y Janice A. Lansita.<br>Ph.D.
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Taylor, James Ward. "Physicochemical complexity in complex chemical systems." Thesis, University of Glasgow, 2016. http://theses.gla.ac.uk/7772/.
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Self-replication and compartmentalization are two central properties thought to be essential for minimal life, and understanding how such processes interact in the emergence of complex reaction networks is crucial to exploring the development of complexity in chemistry and biology. Autocatalysis can emerge from multiple different mechanisms such as formation of an initiator, template self-replication and physical autocatalysis (where micelles formed from the reaction product solubilize the reactants, leading to higher local concentrations and therefore higher rates). Amphiphiles are also used in artificial life studies to create protocell models such as micelles, vesicles and oil-in-water droplets, and can increase reaction rates by encapsulation of reactants. So far, no template self-replicator exists which is capable of compartmentalization, or transferring this molecular scale phenomenon to micro or macro-scale assemblies. Here a system is demonstrated where an amphiphilic imine catalyses its own formation by joining a non-polar alkyl tail group with a polar carboxylic acid head group to form a template, which was shown to form reverse micelles by Dynamic Light Scattering (DLS). The kinetics of this system were investigated by 1H NMR spectroscopy, showing clearly that a template self-replication mechanism operates, though there was no evidence that the reverse micelles participated in physical autocatalysis. Active oil droplets, composed from a mixture of insoluble organic compounds in an aqueous sub-phase, can undergo processes such as division, self-propulsion and chemotaxis, and are studied as models for minimal cells, or protocells. Although in most cases the Marangoni effect is responsible for the forces on the droplet, the behaviour of the droplet depends heavily on the exact composition. Though theoretical models are able to calculate the forces on a droplet, to model a mixture of oils on an aqueous surface where compounds from the oil phase are dissolving and diffusing through the aqueous phase is beyond current computational capability. The behaviour of a droplet in an aqueous phase can only be discovered through experiment, though it is determined by the droplet's composition. By using an evolutionary algorithm and a liquid handling robot to conduct droplet experiments and decide which compositions to test next, entirely autonomously, the composition of the droplet becomes a chemical genome capable of evolution. The selection is carried out according to a fitness function, which ranks the formulation based on how well it conforms to the chosen fitness criteria (e.g. movement or division). Over successive generations, significant increases in fitness are achieved, and this increase is higher with more components (i.e. greater complexity). Other chemical processes such as chemiluminescence and gelation were investigated in active oil droplets, demonstrating the possibility of controlling chemical reactions by selective droplet fusion. Potential future applications for this might include combinatorial chemistry, or additional fitness goals for the genetic algorithm. Combining the self-replication and the droplet protocells research, it was demonstrated that the presence of the amphiphilic replicator lowers the interfacial tension between droplets of a reaction mixture in organic solution and the alkaline aqueous phase, causing them to divide. Periodic sampling by a liquid handling robot revealed that the extent of droplet fission increased as the reaction progressed, producing more individual protocells with increased self-replication. This demonstrates coupling of the molecular scale phenomenon of template self-replication to a macroscale physicochemical effect.
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Rawson, Jolyon Oliver. "Physicochemical studies of clay polymer interactions." Thesis, Sheffield Hallam University, 1995. http://shura.shu.ac.uk/20267/.
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This thesis reports investigations into the colloid and solid state properties of clay/polymer complexes. The interactions between water soluble polymers and clay were investigated because of their importance to the oil industry which make use of clay/polymer interactions to control certain properties of drilling muds. [133]Cs and to a lesser extent [23]Na NMR have been evaluated as novel in situ probes to study the adsorption of polycations, and other cationic species, onto 25 gL[-1] suspensions of Westone-L. Westone-L is a low iron containing montmorillonite which was completely exchanged with either Cs[+] or Na[+] cations. The polycations FL15, FL16 and FL17, of general formula [(Me[2]NCH[2]CHOHCH[2)[n]][n+], and Magnafloc 1697, [(CH[2]CHCH[2]N(Me)[2]CH[2]CHCH[2])[n]][n+] have been shown to displace the exchangeable cation from the clay surface more effectively than other cationic species investigated such as Na[+], K[+], MeN[4+] and paraquat[2+]. This was shown through a decrease in linewidth and an increase in the [133]Cs or [23]Na NMR peak integral as cationic species were added to the clay. This information has been correlated with that obtained from particle size and zeta potential measurements in aqueous solution which suggest that the highly charged polycations investigated adsorb onto the surface of the clay via an 'electrostatic patch' mechanism. To complement these aqueous in situ techniques, several dry powder studies have been completed, including adsorption isotherms through Kjeldahl N analysis, variable temperature x-ray diffraction and thermogravimetric studies. These dry powder studies show conclusively that the exchangeable cation associated with the clay surface has a large bearing upon the amount and location of polymer adsorbed. The neutral polyglycol DCP101 is presently finding widespread use as a shale inhibitor in drilling muds. The mechanism by which this polymer interacts with clay has been investigated by recording the [133]Cs and [1]H NMR spectra of 25 gL[-1] suspensions of Cs[+] and Mn[2+] exchanged Westone-L treated with DCP101. These novel in situ investigations have shown that DCP101 does not displace the exchangeable cation associated with the clay. They have also shown that the water molecules in the hydration sphere of the Mn2+ cation associated with the clay surface are predominantly undisturbed by added DCP101. To complement these aqueous in situ investigations, several dry powder studies were carried out including adsorption isotherms through CHN analysis, variable temperature x-ray diffraction and thermogravimetric studies. These dry powder studies show that the exchangeable cation has a large bearing upon the quantity of polymer adsorbed. One further in situ NMR method has been evaluated with a view to investigating clay/polymer interactions. This method involved the addition of 10% D[2]O to a 40 gL[-1] suspension of clay which had been exchanged to the cation of interest. The resulting [2]H NMR spectrum showed a residual quadrupolar splitting, the magnitude of which depended upon several factors including clay concentration, state of aggregation of the clay platelets and the exchangeable cation associated with the clay. It was hoped that by monitoring the clay/D[2]O interactions via the [2]H residual quadrupolar splitting that information about clay/polymer systems in aqueous suspension would be forthcoming. The observed [2]H residual quadrupolar splitting was however found to be too sensitive to addition of polymer or ions to the clay suspension, resulting in its collapse to a singlet.
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Griffith, Vivienne Jean. "Physicochemical characterisation of cyclodextrin-drug complexes." Doctoral thesis, University of Cape Town, 1996. http://hdl.handle.net/11427/25979.
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The cyclodextrins and their derivatives are finding increasing application in the pharmaceutical industry as carrier molecules for many drugs, as complexation can result in improved physical characteristics such as increased aqueous solubility and dissolution rates. The aim of this work was to prepare solid cyclodextrin complexes with selected drugs which have already been shown to interact with cyclodextrins in solution and ultimately to grow crystals of these inclusion complexes of sufficient quality for single crystal X-ray structure determination. The designated drugs included an antibacterial, sulfathiazole; three non-steroidal anti-inflammatory drugs (NSAIDs), (S)-naproxen and the sodium salts of diclofenac and meclofenamic acid; and (L)-menthol, a compound used in many pharmaceutical preparations. The chosen host molecules were ,β-cyclodextrin, γ-cyclodextrin, heptakis(2,6-di-O-methyl)-, β-cyclodextrin (DIMEB) and heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin (TRIMEB). The unit cell parameters of thirteen cyclodextrin-drug complexes and of TRIMEB monohydrate were determined by X-ray photography and the cry tal structures of six of these complexes and of TRIMEB monohydrate were solved. The water content of the complexes was established by thermogravimetric analysis and the host:guest stoichiometries of those complexes whose crystal structures were not solved were determined by UV spectrophotometry or, in one case, by a combination of NMR and thermogravimetric analysis. The complexes were also characterised by differential scanning calorimetry. Hot stage microscopy was a useful method for initial testing for the formation of inclusion complexes of the native cyclodextrins, since their behaviour on heating differs markedly from that of the relevant host alone. The events observed could be correlated with the thermal analyses of the complexes. Complexes which contained alkali metal cations appeared to retain water molecules of crystallisation to higher temperatures, on average, than those which did not. XRD patterns were calculated from the crystal structures which were solved and matched the experimental patterns of the prepared samples well. The calculated patterns serve as the best references for establishing the identity and purity of prepared complexes. Host-guest interactions included hydrogen bonding, van der Waals contacts and hydrophobic interactions. Guest molecules maintained similar conformations on the whole as those observed in other crystal structures containing these particular guests. Conformations of the hosts were akin to those found in known crystal structures, except in TRIMEB monohydrate, where the TRIMEB conformation was distorted to a remarkable extent even in comparison with the distorted conformations observed in its complexes. In addition, one of the methylglucose residues is present in the ¹C₄ inverted chair conformation which has not been observed before in the cyclodextrins or their complexes in the solid state. The invariable occurrence in the TRIMEB host of C(6Gn)-H···0(5Gn-1) hydrogen bonds noted in this study is partly responsible for the uniformity in the conformation of TRIMEB in its complexes. The packing arrangement found in the diclofenac sodium-β-CD complex is unique and is the first example of a β-CD complex crystallising in the hexagonal crystal system. The inclusion by β-CD of meclofenamate sodium (a structural isomer of diclofenac sodium) is similar to that of diclofenac sodium, but the packing arrangement is different and while unique for a complex of unsubstituted β-CD, resembles the packing arrangement found in most of the known TRIMEB complexes.
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ABBAS, IBRAHIM RASHEED. "PHYSICOCHEMICAL PROPERTIES OF TEPARY BEAN STARCH." Diss., The University of Arizona, 1987. http://hdl.handle.net/10150/183997.
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The composition of tepary beans Phaseolus acutifolius var. latifolius was determined; starch (41%) and protein (26.3%) were the predominant components. The physical, physicochemical, rheological, structural and nutritional properties of the isolated starch and its suitability in food products were evaluated. Starch granules were spherical to oval with a typical legume starch birefringence pattern. They appeared smooth and showed a normal distribution of diameters (range 15.5 - 59.9 μ; mean 33.5 μ). Tepary starch had an amylose content of 30.7% and a gelatinization temperature range of 70.5 - 84.0°C. Other physicochemical values were as follows: phosphorus, 0.01%; iodine binding capacity, 6.14%; alkali number, 8.97; inherent viscosity, 2.44 ml/g; water binding capacity, 82.1%; swelling power, 13; solubility, 17.9%; and sag, 6.26%. Fractionation provided an amylose fraction with a β-amylolysis of 76.3%, limiting viscosity of 83.5 ml/g and a DP(η) of 618. Amylopectin (iodine binding capacity, 0.88%) had a DP(η) of 1094, limiting viscosity of 91.1 ml/g and CL, OCL, and ICL values of 33, 22 and 10 glucose units, respectively. Gelatinization of tepary starch was a single-step process. Pasting viscosity was stable when starch suspensions were cooked at 95°C for 15 min; viscosity progressively increased when pastes cooled to 50°C. At 4 and 6%, tepary starch pastes resembled a type C viscosity pattern, whereas at 7% and above, pasting behavior exhibited a type B pattern. Pastes were stable at pH 5 to 9 but showed faster breakdown and no retrogradation at pH 3. Addition of sucrose and salt changed rheological behavior; 2% oil had no effect on pasting. Sensory evaluation of tepary starch vanilla pudding established its consumer acceptability. In vitro determination indicated that raw tepary starch was poorly digested (8%). Digestibility improved (from 8 to 82%) upon cooking. Raw corn starch was more digestible (25.6%) than tepary starch. Freeze-drying reduced the hydrolysis of all materials evaluated (i.e. 8.64 to 3.21%, 8.03 to 2.63% and 25.6 to 17.8% for tepary flour, tepary starch and corn starch, respectively). Autoclaving decreased the digestibility of tepary flour (8.64 to 5.72%), and tepary starch (8.03 to 7.38%), but it slightly improved that of corn starch (25.6 to 27.7%).
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Karmakar, Gourab. "Physicochemical investigation on Nanostructural Lipid Carriers." Thesis, University of North Bengal, 2018. http://ir.nbu.ac.in/handle/123456789/2855.
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Nilsson, Johanna. "CORRELATIONS BETWEEN PHYSICOCHEMICAL PROPERTIES IN MATERIALS COMPRISING MICROFIBRILLATED CELLULOSE : CORRELATIONS BETWEEN PHYSICOCHEMICAL PROPERTIES IN MATERIALS COMPRISING MICROFIBRILLATED CELLULOSE." Thesis, Umeå universitet, Kemiska institutionen, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:umu:diva-185526.
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Microfibrillated cellulose (MFC) films have gained a lot of industrial interest lately dueto their good barrier properties and good mechanical strength. In this study it wasinvestigated whether rheological characteristics and conductivity of MFC dispersionscomprised of different MFC grades could be correlated to tensile properties of the MFCfilms produced from the corresponding MFC dispersion. A rheological characterizationmethod was developed for MFC dispersions with 3 wt% MFC and a secret additiveusing a dynamic rotational rheometer and a smooth “plate to plate” geometry. Themethod consisted of an amplitude sweep, a frequency sweep, and a controlled shearrate measurement. Two predicting OPLS models were created in SIMCA: model 1correlated values from rheological measurements and ionic conductivity to tensileproperties and model 2 correlated MFC grades to tensile properties. A slight correlationbetween MFC rheology and tensile properties could be observed, but due to the lowpredictive ability of model 1 (Q2=0.47) it was deemed that the model was insufficientas a tool for facilitated predictions of new samples. It was concluded that tensileproperties are more correlated to the composition of MFC dispersions than whatrheological characteristics and ionic conductivity the dispersions display, based on thegood predictive ability of model 2 (Q2=0.59).
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McDonald, Caleb Benton. "Physicochemical Studies of the Grb2-Sos1 Interaction." Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_dissertations/260.
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Grb2, a modular protein comprised of a central SH2 domain flanked between a N-terminal SH3 (nSH3) domain and a C-terminal SH3 (cSH3) domain, is a component of cell signaling networks involved in the transmission of extracellular information in the form of growth factors and cytokines to downstream targets such as transcription factors within the nucleus. The Grb2-Sos1 interaction is mediated through the combinatorial binding of nSH3 and cSH3 domains of Grb2 to various sites - designated S1, S2, S3, and S4 - containing PXpsiPXR motifs within Sos1. Here, using a diverse array of biophysical techniques, including in particular isothermal titration calorimetry coupled with molecular modeling and semi-empirical analysis, I provide new insights into the Grb2-Sos1 interaction in thermodynamic and structural terms. My data show that Grb2 exists in monomer-dimer equilibrium in solution and that the dissociation of dimer into monomers is entropically-driven. The heat capacity change observed was much smaller than that expected from the rather large molecular surfaces becoming solvent-occluded upon dimerization, implying that monomers undergo conformational rearrangement upon dimerization. 3D structural models suggest strongly that such conformational rearrangement may arise from domain swapping. I further show that the nSH3 domain of Grb2 binds to the S1 site containing the proline-rich consensus motif PXpsiPXR with an affinity that is nearly three-fold greater than that observed for the binding of the cSH3 domain. It is also demonstrated that such differential binding of the nSH3 domain relative to the cSH3 domain is largely due to the requirement of a specific acidic residue, in the RT loop, to engage in the formation of a salt bridge with the arginine residue in the consensus motif PXpsiPXR. The data further reveal that, while binding of both SH3 domains to Sos1 is under enthalpic control, the nSH3 binding suffers from entropic penalty in contrast to entropic gain accompanying the binding of cSH3, implying that the two domains employ differential thermodynamic mechanisms for Sos1 recognition. Additionally, my data reveal that while the nSH3 domain of Grb2 binds with affinities in the physiological range to all four sites S1-S4, the cSH3 domain can only do so at the S1 site. Further scrutiny of these sites yields rationale for the recognition of various PXpsiPXR motifs by the SH3 domains in a discriminate manner. Unlike the PXpsiPXR motifs at S2, S3 and S4 sites, the PXpsiPXR motif at S1 site is flanked at its C-terminus with two additional arginine residues that are absolutely required for high-affinity binding of the cSH3 domain. In contrast, these two additional arginine residues augment the binding of the nSH3 domain to the S1 site but their role is not critical for the recognition of S2, S3 and S4 sites. Molecular modeling is employed to rationalize my new findings in structural terms. Taken together, this thesis provides novel insights into the physicochemical basis of a key protein-protein interaction pertinent to cellular signaling and cancer. My studies bear the potential for the development of novel therapies with less toxicity but more effectiveness for the treatment of disease.
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Chatterjee, Subhrangsu. "Physicochemical and Structural Aspects of Nucleic Acids." Doctoral thesis, Uppsala : Acta Universitatis Upsaliensis, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-8360.
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Hosseini, Seyed Hamid. "Physicochemical studies of oxide zinc mineral flotation /." Luleå : Division of Mineral Processing, Department of Chemical Engineering and Geosciences, Luleå University of Technology, 2008. http://epubl.ltu.se/1402-1544/2008/17/.
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Wang, Niya. "Physicochemical Changes of Coffee Beans During Roasting." Thesis, The University of Guelph, 2012. http://hdl.handle.net/10214/3584.
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In this research, physicochemical changes that took place during roast processing of coffee beans using fluidized air roaster were studied. The results showed that high-temperature-short-time resulted in higher moisture content, higher pH value, higher titratable acidity, higher porous structure in the bean cell tissues, and also produced more aldehydes, ketones, aliphatic acids, aromatic acids, and caffeine than those processed at low-temperature-long-time process. Fourier transform infrared (FTIR) spectroscopy and chemometric analysis showed that clusters for principal components score plots of ground coffee, extracted by a mixture of equal volume of ethyl acetate and water, were well separated. The research indicated that variations in IR-active components in the coffee extracts due to different stages of roast, roasting profiles, and geographical origins can be evaluated by the FTIR technique.<br>Natural Sciences and Engineering Research Council of Canada (NESRC) and Mother Parkers Tea & Coffee Inc.
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Ge, R. "Measurement of Physicochemical Properties of Ionic Liquids." Thesis, Queen's University Belfast, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527700.
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Wheale, Samantha Hilary. "Physicochemical phenomena at the plasma-polymer interface." Thesis, Durham University, 1997. http://etheses.dur.ac.uk/4977/.
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Non-isothennal plasma modification of polymer surfaces is of scientific and technological interest, since it can be used to improve wettability, adliesion, etc. This thesis covers three main areas, firstly a study of the processes occuixing at the plasma - polymer interface using a newly developed technique, secondly the fluorination of polymer surfaces using a novel transportable reagent and lastly the oxidation of rubber substrates. The interaction of N(_2), O(_2), air and H(_2) glow discharges with polyethylene surfaces has been studied using a newly developed mass spectrometric technique. The species permeating through to the reverse side of the polymer substrate can be detected and characterised. Compared to previously reported approaches, this method is capable of sampling reaction products within closer proximity to the plasma - polymer interface, thereby circumventing the complication of primary product species undergoing secondary processes within the bulk of the electrical discharge prior to detection. The nature of the feed gas is found to strongly influence the chemical reaction pathways occurring at the plasma - polymer interface. Xenon difluoride (XeF(_2)) plasma treatment of a series of polymers containing different repeat units gives rise to surface fluorination. A comparison with CF(_4) plasma modification shows that XeF(_2) electrical discharges are more effective at fluorinating polymers. The extent of fluorine incorporation can be accounted for in terms of a structure-behaviour relationship derived from extended Huckel molecular orbital calculations. Exposure of polyethylene and polystyrene to xenon difluoride (XeF(_2)) in the presence of vacuum ultraviolet (VUV) irradiation also causes surface fluorination. The extent of reaction is found to depend upon the VUV absorption characteristics of the XeF(_2) feed gas as well as those of the polymer substrate. Low pressure glow discharge, dielectric barrier discharge and ozone treatments all oxidise additive-free rubber substrates. The oxidation susceptibility of the rubber substrates differed during all three treatments, and was found to be dependent upon the concentration of unsaturated carbons, saturated carbons and phenyl rings. The additives placed ill rubbers to improve properties such as tear resistance influence their degree of oxidation.
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MacLaughlin, Fiona Caroline. "DNA delivery : physicochemical properties of DNA:polycation complexes." Thesis, University of Nottingham, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.338437.
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Badruddin, Ahmad Fasihuddin. "Physicochemical characterisation and properties of sago starch." Thesis, University of Salford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265740.
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Pechmann, Sebastian. "Insights into physicochemical principles of protein homeostasis." Thesis, University of Cambridge, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.611798.
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Denda, Mitsuhiro. "Physicochemical features of human skin stratum corneum." Kyoto University, 1994. http://hdl.handle.net/2433/160747.
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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである<br>Kyoto University (京都大学)<br>0048<br>新制・論文博士<br>博士(工学)<br>乙第8661号<br>論工博第2902号<br>新制||工||970(附属図書館)<br>UT51-94-R420<br>(主査)教授 中西 浩一郎, 教授 森島 績, 教授 砂本 順三<br>学位規則第4条第2項該当
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Cha, Won-ill. "Physicochemical studies on poly (vinyl alcohol) hydrogels." Kyoto University, 1994. http://hdl.handle.net/2433/168897.
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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである<br>Kyoto University (京都大学)<br>0048<br>新制・論文博士<br>博士(工学)<br>乙第8528号<br>論工博第2849号<br>新制||工||958(附属図書館)<br>UT51-94-J257<br>(主査)教授 筏 義人, 教授 升田 利史郎, 教授 池内 健<br>学位規則第4条第2項該当
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Bussio, John. "Physicochemical analysis of South African metamorphosed coal." Thesis, University of Pretoria, 2020. http://hdl.handle.net/2263/72838.
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An in-depth understanding of the physico-chemical nature of coal is required in order to meet ever-increasing energy demands and environmental legislature. New and classical coal analysis techniques were used on thermally-affected coals from a working coalfield in Secunda, South Africa. The study area has ubiquitous dolerite intrusions that have large-scale impacts on the minable coal resource.
A combination of five modern and classical analysis techniques, namely Schmidt hammer testing, three-dimensional X-ray tomography, proximate analysis, petrographic analysis with reflectance analysis, and two-dimensional gas chromatography time of flight mass spectrometry (GC*GCTOFMS) were used to model the mechanics of metamorphism of coal intruded by an igneous body. Freshly exposed coalface with an intersecting dolerite was analysed. The data produced from GC*GCTOFMS, reflectance, and tomographic analysis produced no strong linear correlations. Thermal dolerite influence was capped at approximately 5m from the dolerite intrusion and of note was a secondary trend that identified peaks throughout the transect correlating across GC*GCTOFMS, reflectance, and tomographic analysis. To reconcile the non-linear correlation a model using a combination of hydrothermal and thermal influences was produced to explain the mechanics of the metamorphic environment.<br>Thesis (PhD)--University of Pretoria 2020.<br>Geology<br>PhD<br>Unrestricted
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Ashurst, Ian C. "Physicochemical characteristics of chlorofluorohydrocarbon based inhalation aerosols." Thesis, Aston University, 1985. http://publications.aston.ac.uk/12546/.
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The aim of this work was to gain a better understanding of the physiochemical factors which affect the formulation of suspension inhalation aerosols. This has been attempted by applying the principles of colloid science to aerosol formulation. Both a drug system and a model colloid system have been used. The adsorption of six nonionic and cationic surfactants onto Spherisorb has been investigated. The results were analysed by calculating the area occupied by one adsorbed molecule at the surface and by comparing these values for each surfactant. The amount of each surfactant adsorbed was correlated with the number of sites on that surfactant molecule which could interact with the surface. The stability of suspensions, produced by both the model colloid Spherisorb, and by the drug isoprenaline sulphate, after adsorption of the surfactants, has been assessed by measuring settling times and rising times. The most stable suspensions were found to be those which had the greatest amounts of long chain fatty acid surfactant adsorbed on their surface. A comparison was made between the effective stabilising properties of Span 85 and oleic acid on various drug suspensions. It was found that Span 85 gave the most stable suspensions. Inhalation aerosol suspensions of isoprenaline sulphate were manufactured using the same surfactants used in the adsorption and suspension stability studies and were analysed by measuring the particle size distributions of the suspension and the emitted doses. The results were found to correlate with the adsorption and suspension stability studies and it was concluded that a deflocculated suspension was preferable to a flocculated suspension in inhalation aerosols provided that the drug density was less than the propellant density. The application of this work to preformulation studies was also discussed.
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Zhang, Yue. "The Physicochemical Properties of Secondary Organic Materials." Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17467502.
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The physicochemical properties of the secondary organic materials (SOMs) that constitute the particle phase have potentially important consequences for the growth, the reactivity, and ultimate fate of atmospheric organic aerosols, thereby affect climate, human health and visibility. A quantitative analysis of the physicochemical properties of the SOMs is important, but challenging. This thesis presents laboratory studies of α-pinene derived SOMs, which is one of the major components of secondary organic aerosols (SOAs) in the forests, by combing a flow tube reactor, aerosol particle mass analyzer (APM) and other online/offline measurement techniques.
A water-jacketed constant temperature flow tube reactor was built to produce SOM particles grown from either condensation or coagulation. Different ratios of α-pinene enantiomers were mixed and injected into the flow tube reactor for dark ozonolysis. A matrix of organic precursor and ozone concentrations was designed and tested in order to determine the optimal concentration to switch between condensation and coagulation. Results show that at 51 ± 1 ppm O3, condensation is the dominant growth mechanism when the α-pinene concentration is 0.125 ± 0.001 ppm, and coagulation is the dominant growth mechanism when the α-pinene concentration increases to 1.00 ± 0.03 ppm. A combination of both growth mechanisms is observed when the α-pinene concentration is in between the described values.
The study also proposed and tested the hypothesis that a 50:50 mixture of α-pinene enantiomers may result in SOM particles that have different physical properties, such as number-diameter distributions, when compared with those particles generated from a single enantiomer of α-pinene. The experiment was conducted within the condensational growth regime so that the chirality induced structure differences in oligomers can be maximized during the nucleation and condensation. Nevertheless, our analysis indicates that, after removing the effects of ozone and temperature, the chirality-induced effects are minimal and within our detection limit. Even though the results were negative, the method used in this experiment provided useful experience for the viscosity related experiments in this thesis.
Another important property of the SOM is its viscosity. The viscosities of atmospheric particles determine whether their interactions with surrounding gases are confined to the surface or can proceed to the interior. Viscosities affect the gas-particle diffusion rate, and ultimately influences the SOM’s other physical properties, such as particle size, and chemical properties, such as reactivity. The work presented in this thesis estimates the viscosity of submicron organic particles while they are still suspended as an aerosol without further post-processing techniques that can have the possibility of altering the properties of semivolatile materials. The results show that the studied particles are semisolid up to 58% relative humidity (RH) and may become liquid only at a higher RH. These results imply that atmospheric particles, at least those similar to the ones studied and for low to middle RH regimes, are expected to reach equilibrium only rather slowly with the chemical composition of the gas phase, sometimes on timescales longer than the actual residence time of the particles in the atmosphere.
Last but not the least, the results of offline particle analysis from two collaboration studies are also discussed in this thesis. The results show how water vapor, or RH, affects the physicochemical properties of the α-pinene derived SOM particles. In one study, the diffusivity is underestimated by approximately 8 orders of magnitude if calculated from the Stokes-Einstein equation, which suggests the breakdown of Stokes-Einstein equation for small gas molecules. The second study shows the surface properties of SOM particles can be influenced by the RH, leading to a difference of the gas-particle interactions at the particle surface.<br>Engineering and Applied Sciences - Engineering Sciences
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Kubota, Keigo. "Physicochemical properties of alkali perfluoroalkylsulfonylamides and fluorosulfonylamides." Kyoto University, 2010. http://hdl.handle.net/2433/120412.
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Kaiser, Achim. "Physicochemical Properties and Synthesis of Oligothiophene Macrocycles." [S.l. : s.n.], 2008. http://nbn-resolving.de/urn:nbn:de:bsz:289-vts-64614.
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Pena, Marcos Miguel Gonzalez. "Comparative physicochemical characterisation of thermally modified wood." Thesis, Bangor University, 2007. https://research.bangor.ac.uk/portal/en/theses/comparative-physicochemical-characterisation-of-thermally-modified-wood(544e97d3-72ad-444e-9ebc-4a5076663cd9).html.
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Small matched samples of beech, Scots pine and Norway spruce woods were heattreated to twenty schedules, at temperatures of 190, 210, 230 and 245°C for heating periods of 0.3, 1, 4, 8 and 16 h. Following thermal modification, physical changes and chemical composition in thermally modified wood (TMW) were analysed and compared to the characteristics of untreated materials. Most of the analysis were carried out using the heat-induced weight loss values (WL, %) as the independ~nt variable to make the comparisons. Average treatment WL values ranged from 0.3 to 27.0, from 0.6 to 21.5, and from 1.0 to 26.7 for beech, pine, and spruce samples respectively. A major finding of this research was that each characteristic changed following the same profile in the three wood species for all properties studied. Save for hardness in beech, the magnitude and rate of change of each property was often found not to be significantly different between species when relative-to-control values in function ofthe WL were compared. The results show that the gravimetric and dimensional changes in the transverse plane are mainly due to chemical breakdown of wood hemicelluloses. On the other hand, the readiness ofTMW to dimensional changes and moisture uptake below the FSP was of a much lower concern than in raw wood. Similarly, several mechanical properties were found to be little affected by heat exposure at treatment levels likely to be achieved industrially. Among these were compression strengths parallel and perpendicular to the axis in the tangential direction, and the axial modulus of elasticity in bending (MOE). Other mechanical strength parameters (e.g. shear strength, hardness and the modulus of rupture in bending) were reduced at almost any given treatment schedule, but the rate of reduction was mild. It is contended that design practices could make up for the strength loss incurred by the treatment for these properties. On the other hand, parameters related to the energy required to produce failure and also impact strength were greatly diminished at low levels of modification. This may restrict the use of TMW where unpredictable sudden loads may occur. Properties at the limit of proportionality were found to be less reduced than the same property at maximum load. Mechanical properties more affected by heat were found to be those more intimately related to the chemical integrity of the wood material and/or the structural configuration of wood polymers in the cell wall substance, whilst compression strength and hardness were more related to wood density. MOE was proposed to be more dependent of cellulose, microfibril angle and wood density, all of these little altered by wood heating. Lastly, a description of the colour changes in the test samples was undertaken using image analysis and qualitatively by infrared spectroscopy. It was determined that colour changes in wood were caused mainly by changes in the lignin. The major input of this work to the state of the art is given by modelling the properties studied using various linear, non-linear and multivariate methods. Properties in TMW were estimated from gravimetric, colour and moisture-related parameters. Solid-state mid-infrared spectra data, treatment parameters and interrelationship between variables were also explored. It is concluded that all changes in small heated samples of wood are amenable to be estimated efficiently in multiple ways, using cost-effective indicators. Remarkably encouraging results for the prediction of physical properties were found for models using colour parameters or by the analysis of the infrared spectra data. Whilst descriptions of the heat-induced changes in wood exist, prediction studies are fairly scarce and not comprehensive. This part of the study is thus very timely, giving the current requirements of quality control and assurance of TMW at the industrial stage. The relevance of these fmdings to property prediction in larger wood members would depend on the property considered; safety factors will probably be needed for some forms ofwood strength in larger heated materials.
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COSTANTINI, GABRIELE. "Preparation and physicochemical characterization of glycoconjugate vaccines." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2012. http://hdl.handle.net/10281/29779.
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The project of my PhD course has been focused on the characterization of glycoconjugate vaccines to develop a largely applicable methodology to identify their glycosylation sites.
The saccharide antigens are covalently attached to the carrier protein by a spacer or using specific functionalities available in both components. The general analytical strategy has involved a tryptic digestion and an enzymatic or acid hydrolysis of carbohydrate antigens in glycoconjugates. The resulting mixture of peptides and glycopeptides with well-defined mass increment has been analyzed by liquid chromatography interfaced with a mass spectrometer (LC-MS) technique to qualitatively understand which lysine residues have been involved in the glycosylation process. Several conjugate vaccines against Candida albicans, Group A Streptococcus (GAS), Group B Streptococcus (GBS) and Neisseria meningitidis group A (MenA) have been analyzed to estimate the distribution of glycosylated lysine residues. Among those, GBS resulted the less glycosylated in comparison to Candida and MenA ones. This aspect it is probably due to the different conjugation chemistries and GBS polysaccharide size. The second part of my PhD project has been the synthesis of two β(1,3)-glucans antigens, a trisaccharide and a hexasaccharide and their conjugation to CRM197. The hexasaccharide has also been linked on a multimeric structure PAMAM4 and then conjugated to CRM197. The last part of this work has been the conjugation to CRM197 of a modified MenB LPS, provided from Institute of Biological Science (IBS) laboratory (National Research Council - Ottawa Canada).
The target sites of the carrier protein (CRM197) and LPS have been activated by two different reactans, and the final glycoconjugate has been obtained by the reaction of these two.
The resulting conjugate has been characterized (saccharide and protein content, MALDI-TOF mass spectrometry and NMR) using an accurate analytical panel.
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De, Souza Ivan J. "Physicochemical changes of cellulose subjected to oxidative conditions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape3/PQDD_0029/MQ64340.pdf.
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De, Souza Ivan J. "Physicochemical changes of cellulose subjected to oxidative conditions." Thesis, McGill University, 1999. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=30364.
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This study focuses on understanding the physicochemical properties of cellulose as it undergoes the oxygen delignification process. Cellulose contributes to fibre strength but is degraded by oxygen attack. Four different types of cellulose, namely a fully bleached softwood pulp (Q-90), hemicellulose reduced pulp derived from Q-90, cotton cellulose and microcrystalline cellulose (Avicel), were subjected to pressurised oxygen and nitrogen treatments in a kettle reactor. The changes in relative degree of crystallinity, viscosity and carboxylic acid content as a function of time were used to evaluate cellulose degradation. X-ray diffraction, Fourier transform infrared (FTIR) spectroscopy and 13C solid state nuclear magnetic resonance (NMR) spectroscopy determined the relative degree of crystallinity. Viscosity and conductometric titration measurements followed the changes in the degree of polymerisation and carboxylic acid content respectively.<br>A plot of relative degree of crystallinity as a function of oxidation time showed reproducible and consistent results for all celluloses with all applied techniques. The relationship showed a common trend wherein three phases were apparent: an initial increase in relative degree of crystallinity was followed by a decrease and then another gradual increase. The change from a decrease in relative degree of crystallinity to an increase occurred at fifteen minutes for Q-90 and hemicellulose reduced pulp, and at minutes for cotton cellulose. No change in the relative degree of crystallinity with time was evident for Avicel. These trends were rationalised using the concept of the fringed micelle model.
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衛星輝 and Sing-fai Wai. "Physicochemical characterization of brain ganglioside-stimulated protein kinase." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1997. http://hub.hku.hk/bib/B31236212.
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張志田 and Zhitian Zhang. "Nutritional quality and starch physicochemical properties in sweetpotato." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B31242728.
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Andrews, G. P. "Physicochemical characterisations of novel pharmaceutical polymer gel networks." Thesis, Queen's University Belfast, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.397846.
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Knaggs, Roger D. "Physicochemical properties of opiates : analytical and biological relevance." Thesis, University of Nottingham, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.363687.
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Asamoa, Akua. "A physicochemical study of a sparingly soluble drug." Thesis, University of Kent, 1993. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.359030.
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Rudd, Nicola Clare. "Micro- and nanoscale investigations of interfacial physicochemical processes." Thesis, University of Warwick, 2007. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.445522.
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