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MENEGAZZO, ANA P. M. "Estudo da correlacao entre a microestrutura e as propriedades finais de revestimentos ceramicos do tipo gres porcelanato." reponame:Repositório Institucional do IPEN, 2001. http://repositorio.ipen.br:8080/xmlui/handle/123456789/10892.
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Tese (Doutoramenro)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN/CNEN-SP
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Maribeng, Lebea. "The influence of parent material (granite and schist) on physical and chemical properties of soils on the Syferkuil Experimental Farm." Thesis, University of Limpopo (Turfloop Campus), 2007. http://hdl.handle.net/10386/606.
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Thesis (M.Sc. (Soil Science)) --University of Limpopo (Turfloop campus), 2007The influence of parent material on physical and chemical properties of soil was studied on granite and schist derived soils on the Syferkuil Experimental Farm, situated in the Mankweng area of the Limpopo Province of South Africa. A total of 49 samples of virgin soils were collected, where granite soils constituted 26 samples and schist soils 23. The study design that was used is cross-sectional. The samples were analysed for physical and chemical properties. The physical properties of granite and schist soils were determined as percentages coarse sand, percentages medium sand, percentages fine sand, percentages very fine sand, percentages silt and percentages clay, whilst the chemical properties were determined as concentrations (cmol (+) kg-1) of Na, Mg, Ca, K ,ESP, CEC and P (mg kg-1), as well as pH. Statistical analysis of the results was performed by application of the Unpaired Student’s T Test, with the level of significance at p<0.05. The results showed that soils derived from granite had significantly higher coarse and medium sand fractions than schist soils; whereas schist soils were significantly higher in fine sand, very fine sand, silt and clay. The concentrations of Na, Ca, ESP and P, as well as CEC and pH in schist derived soils were higher than in granite derived soils although the differences were insignificant. However, significant differences occurred in K and Mg concentrations where schist derived soils had higher concentrations than granite derived soils. However, the concentrations of nutrient elements were found to be insufficient for proper production in agriculture. The sodium concentration was found to be low enough to not lead to sodic soil conditions. It was concluded that both granite and schist soils can be used for agriculture but require careful management because both soils indicated poor nutritional status.
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Dolejš, David. "Thermodynamics and phase equilibria of the silicate-fluoride-H₂O systems : implications for fluorine-bearing granites." Thesis, McGill University, 2004. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=85066.
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The progressive enrichment in volatiles and light incompatible elements observed during upper-crustal differentiation of granitic and rhyolitic magmas leads to significant changes in melt physical-chemical properties and has important implications for ore deposition and volcanic devolatization. Thermodynamic calculations and experimental studies of melting equilibria in the Na 2O-K2O-Al2O3-SiO2-F 2O-1-H2O system are used to evaluate mineral stabilities, fluid compositions, the extent of fluoride-silicate liquid-liquid immiscibility, fluorine and water solubility limits and differentiation paths of natural fluorine-bearing silicic magmas. The interaction of fluorine with rock-forming aluminosilicates corresponds to progressive fluorination by the thermodynamic component F2O-1. Formation of fluorine-bearing minerals first occurs in peralkaline and silica-undersaturated systems that buffer fluorine concentrations at very low levels (villiaumite, fluorite). The highest concentrations of fluorine are achieved in peraluminous silica-oversaturated systems, saturated with fluorite or topaz. Thermodynamic models of fluorosilicate melts indicate clustering of silicate tetrahedra in the Na2O-SiO 2-F2O-1 system, whereas initial NaAl-F short-range order evolves into partial O-F disorder in the albite-cryolite system. Experiments performed at 520-1100°C and 0.1-100 MPa completely describe liquidus relations and differentiation paths of fluorine-bearing felsic magmas. Coordination differences and short-range order effects between [NaAl]-F, Na-F vs. Si-O lead to the fluoride-silicate liquid immiscibility, which extends from the silica-cryolite binary through the peralkaline albite-silica-cryolite ternary and closes in multicomponent, topaz-bearing systems owing to the destabilizing effect of increasing peraluminosity. Liquidus relations indicate that fluoride-silicate liquid-liquid immiscibility is inaccessible to quartz-feldspar-saturated granitic melt
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Matos, Strauss Javier Fabian. "An εHf and δ18O Isotopic Study of Zircon of the Mount Osceola and Conway Granites, White Mountain Batholith, New Hampshire: Deciphering the Petrogenesis of A-Type Granites." BYU ScholarsArchive, 2021. https://scholarsarchive.byu.edu/etd/9189.
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A-type granites form in anorogenic settings and typically have high REE concentrations, K2O, Na2O, SiO2, FeOtotal, but low contents of Al2O3, MgO, CaO compared to other granite types. They have been divided in two groups according to their geochemical characteristics: differentiates of mantle-derived magmas (A1), and granites that are the result of melting depleted, lower crust (A2). The two largest A-type granites of the Mesozoic White Mountain Batholith of New Hampshire are the Mount Osceola and Conway granites. Electron microprobe analyses of biotite and amphibole in both granites are similar to those in other A-type granites: Fe-rich, but low MgO, and Al2O3. Whole-rock major and trace elements compositions of the Mount Osceola and the Conway granites are similar; both have high contents of REE, Zr, Nb, high Nb/Y ratios, and low CaO, Eu, and Sr and other compatible elements. Based on their high Nb/Y ratios, both granites are classified as mantle-derived magmas (A1). Microanalyses of ẟ18O and ƐHf of zircon show significant crustal contamination in both granites. The ẟ18O values for zircons from the Mount Osceola are between 7.4-8.9‰, and for the Conway Granite are 7.0-8.1‰. These values are distinct from mantle zircon (ẟ18O 5.3±0.3‰), which indicates large degrees of crustal contamination in both granites. Additionally, ƐHf (188Ma) for the Mount Osceola zircon ranges from -1.1 to +3.4, and those from the Conway Granite range from -2.1 to +4.6, indicating magma derivation in depleted mantle (ƐHf > 0) along with a crustal component. Although both granites have A1 compositions suggesting a mantle-derivation, this simple process is not recorded by the zircons. These zircons crystallized after considerable crustal contamination of mantle-derived A1 magmas and missed capturing the signature of that mantle component.
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Nielbock, Markus. "Physical properties of protostars." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962916951.
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Amado, Pedro J. "Physical properties of starspots." Thesis, Queen's University Belfast, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.387975.
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Nilsson, Frederik. "Alkylglucosides physical-chemical properties /." Lund : Physical Chemistry 1, Center for Chemistry and Chemical Engineering, Lund University, 1998. http://catalog.hathitrust.org/api/volumes/oclc/39761789.html.
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Le, Brun Virginie. "Physical Properties of Protein Formulations." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-109666.
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Livings, Simon John. "Physical properties of starch wafers." Thesis, University of Cambridge, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.321480.
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Micciche, Salvatore. "Physical properties of gravitational solitons." Thesis, Loughborough University, 1999. https://dspace.lboro.ac.uk/2134/33196.
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Soliton solutions of Einstein's field equations for space–times with two non-null, commuting Killing Vectors are exact solutions obtained using the solution-generating techniques that resemble the well-known Inverse Scattering Methods that have been widely used m the solution of certain nonlinear PDE's such as Korteweg–de Vries, Sine–Gordon, non-linear Schrödinger. There exist two main soliton techniques in General Relativity. The Belinski–Zakharov technique allows for purely gravitational solutions. The Alekseev technique allows for solutions of the Einstein–Maxwell equations. In both techniques, solitons arise in connection with the poles of a certain so-called "dressing matrix".
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McCoy, James Martin. "The physical properties of magnetic inks." Thesis, Durham University, 1988. http://etheses.dur.ac.uk/6646/.
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The magnetic particle inspection (MPI) method is a widely used non destructive testing (NDT) technique for ferrous structures. Magnetic inks used in MPI are suspensions of fine ferro/ferrimagnetic particles which, when applied to a magnetized test specimen, delineate surface flaws. This work is an investigation of some of the properties of magnetic ink systems and some aspects of their interaction with defect leakage flux. Reviews of magnetism, the MPI method and leakage flux at defects are given. The construction, characterization and automation of a 1.2 T electromagnet vibrating sample magnetometer, used for magnetic measurements on the inks, is described. The instrument has a resolution of better than l0(^-9) JT(^-1) . A 2D model of indication formation in MPI, based upon the simulation of many particles in the neighbourhood of a defect, is presented. Results of the role of several of the model parameters are given. Results indicate that carrier coefficients of viscosity at the lower end of the range investigated (η = 0.3 mPas) are optimum. The size and contrast of an indication increases with defect size. The contrast and rate of formation of contrast increase with defect aspect ratio. The effect of the contrast paint layer thickness indicates that the recommendation of the British Standard, BS 5044 (1973), is qualitatively correct. Experimental observations of particles in field gradients reveals a discrepancy between theoretical and observed behaviour which is attributed, in particular, to unobservable voids in the particles. Detailed characterization of the particles shows them to be aggregates of 20 - 200 nm crystallites which are probably single domain particles. The morphology of larger aggregates is related to measurements of the low field susceptibility. Evidence from intensive magnetic measurements supports the relationship between magnetic properties and aggregate characteristics. A 'In t' magnetic viscosity effect is reported. At 77 K, the coefficient of magnetic viscosity has a maximum near the coercivity field.
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顧若愚 and Ruoyu Gu. "Physical properties of some magnetic systems." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2000. http://hub.hku.hk/bib/B31240173.
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Kefaleas, Christos. "Physical properties of molecules in polyolefins." Thesis, University of Sussex, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391878.
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Gu, Ruoyu. "Physical properties of some magnetic systems /." Hong Kong : University of Hong Kong, 2000. http://sunzi.lib.hku.hk/hkuto/record.jsp?B21981942.
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André, Tomas. "Benchmarking Physical Properties of Water Models." Thesis, Uppsala universitet, Molekyl- och kondenserade materiens fysik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-388336.
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Water is a fundamental part of life as we know it, and by that also a fundamental for biology, chemistry, and parts of physics. Understanding how water behaves and interacts is key in many fields of all these three branches of science. Numerical simulation using molecular dynamics can aid in building insight in the behavior and interactions of water. In this thesis molecular dynamics is used to simulate common rigid 3 point water models to see how well they replicate certain physical and chemical properties as functions of temperature. This is done with molecular dynamics program GROMACS which offers a complete set of tools to run simulations and analyze results. Everything has been automated to work with a python script and a file of input parameters. Most of the models follow the same trends and are valid within a limited temperature range.Vatten är en av de fundamentala byggstenarna för liv, därmed är det även fundamentalt för biologi, kemi och delar av fysiken. Att förstå hur vatten beter sig och interagerar är en stor fråga inom dessa tre grenar av vetenskap. Med molekyldynamik går det att utföra numeriska simuleringar som kan användas som hjälpmedel för att bygga en djupare förståelse för riktigt vatten. I den här uppsatsen så har molekyldynamik använts till att simulera vanliga rigida 3 punkts parametiseringar av vatten för att se hur bra de kan replikera vissa egenskaper som funktioner av temperatur. Simuleringen är gjord med hjälp av molekyldynamik programet GROMACS som ger en fullständig uppsättning verktyg för att simulera och analysera molekylsystem. Alla simuleringar och analys är automatiserat med ett pythonprogram och en fil för parametrar. De allra flesta modeller följer liknande trender och är giltiga inom små temperaturintervall.
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Gilchrist, H. E. M. "Physical properties of continuous random networks." Thesis, Imperial College London, 1987. http://hdl.handle.net/10044/1/38330.
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Rogers, Salman Samson. "Some physical properties of amyloid fibrils." Thesis, University of Cambridge, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.613906.
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Skedung, Lisa. "Tactile perception : role of physical properties." Licentiate thesis, Stockholm : Skolan för kemivetenskap, Kungliga Tekniska högskolan, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-11891.
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Nico, Cláudio Miguel Silva. "Niobium oxides and niobates physical properties." Doctoral thesis, Universidade de Aveiro, 2015. http://hdl.handle.net/10773/14851.
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Doutoramento em Nanociências e NanotecnologiaNiobium oxides have been pointed as an alternative to tantalum in the production of solid electrolytic capacitors, with advantages regarding the dielectric constant, density and price. In this work, it is intended to create a new family of niobium oxides based capacitors, adapting the technology and production line currently used with tantalum. Despite the known potentialities of niobium oxides, and many types of niobates, in several technological applications, the understanding of these oxide systems is still noticeably insufficient. Hence, a careful bibliographic review is shown, which evidences the complexity of these materials, the difficulty in identifying of their different phases and polymorphs, as well as in the interpretation of their properties. In this context, several fundamental studies on niobium oxides are presented, namely structural, microstructural, optical and electrical characterizations, which allow not only to contribute in an important way for the general knowledge of the physical properties of these materials, but also to advance to a sustained development of the niobium oxides based solid electrolytic capacitors. Several processing parameters were studied, clearing the way towards the creation of a prototype. It was also decided to perform a preliminary study on the synthesis and characterization of other oxide systems based in niobium, namely rare-earth orthoniobates (RENbO4), which interest has been related to their optical properties and protonic conductivity. Hence, single and polycrystalline samples of RENbO4 were synthesized and characterized structural, optical and electrically, leaving open an interesting future work.
Os óxidos de nióbio têm sido apontados como uma alternativa ao tântalo na produção de condensadores eletrolíticos sólidos, com vantagens relativamente à constante dielétrica, densidade e preço. Neste trabalho, pretende-se criar uma nova família de condensadores de óxidos de nióbio, adaptando a tecnologia e linha de produção atualmente utilizada com o tântalo. Apesar das já conhecidas potencialidades dos óxidos de nióbio, e vários tipos de niobatos, em diversas aplicações tecnológicas, o conhecimento destes sistemas óxidos é ainda manifestamente insuficiente. Assim, é apresentada uma cuidadosa revisão bibliográfica que evidencia a complexidade destes materiais, as dificuldades na identificação das suas várias fases e polimorfos, assim como na interpretação das suas propriedades. Neste contexto, são apresentados vários estudos fundamentais em óxidos de nióbio, nomeadamente caracterização estrutural, microestrutural, ótica e elétrica, que permitem não só contribuir de uma forma importante para o conhecimento geral das propriedades físicas destes materiais, como avançar para o desenvolvimento sustentado dos condensadores eletrolíticos sólidos à base de óxidos de nióbio. Estudaram-se vários parâmetros de processamento abrindo caminho para a criação de um protótipo. Avançou-se também para um estudo preliminar da síntese e caracterização de outros sistemas óxidos à base de nióbio, nomeadamente ortoniobatos de terras-raras (RENbO4), cujo interesse tem sido manifestado relativamente às suas propriedades óticas e de condutividade protónica. Assim, amostras mono e policristalinas de RENbO4 foram sintetizadas e caracterizadas estrutural, ótica e eletricamente, deixando em aberto um interessante trabalho futuro.
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Wu, Jiajun Ph D. Massachusetts Institute of Technology. "Computational perception of physical object properties." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/103736.
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Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2016.Cataloged from PDF version of thesis.
Includes bibliographical references (pages 49-50).
We study the problem of learning physical object properties from visual data. Inspired by findings in cognitive science that even infants are able to perceive a physical world full of dynamic content at a early age, we aim to build models to characterize object properties from synthetic and real-world scenes. We build a novel dataset containing over 17, 000 videos with 101 objects in a set of visually simple but physically rich scenarios. We further propose two novel models for learning physical object properties by incorporating physics simulators, either a symbolic interpreter or a mature physics engine, with deep neural nets. Our extensive evaluations demonstrate that these models can learn physical object properties well and, with a physic engine, the responses of the model positively correlate with human responses. Future research directions include incorporating the knowledge of physical object properties into the understanding of interactions among objects, scenes, and agents.
by Jiajun Wu.
S.M.
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Hills, Romilly D. Y. "Physical properties of graphene nano-devices." Thesis, Loughborough University, 2015. https://dspace.lboro.ac.uk/2134/17993.
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In this doctoral thesis the two dimensional material graphene has been studied in depth with particular respect to Zener tunnelling devices. From the hexagonal structure the Hamiltonian at a Dirac point was derived with the option of including an energy gap. This Hamiltonian was then used to obtain the tunnelling properties of various graphene nano-devices; the devices studied include Zener tunnelling potential barriers such as single and double graphene potential steps. A form of the Landauer formalism was obtained for graphene devices. Combined with the scattering properties of potential barriers the current and conductance was found for a wide range of graphene nano-devices. These results were then compared to recently obtained experimental results for graphene nano-ribbons, showing many similarities between nano-ribbons and infinite sheet graphene. The methods studied were then applied to materials which have been shown to possess three dimensional Dirac cones known as topological insulators. In the case of Cd3As2 the Dirac cone is asymmetrical with respect to the z-direction, the effect of this asymmetry has been discussed with comparison to the symmetrical case.
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Mitsch, Carsten. "Structure and physical properties of Inovirus." Thesis, University of Cambridge, 1998. https://www.repository.cam.ac.uk/handle/1810/251636.
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Haynes, Kaaren K. "Physical properties of laccase-mediator delignified pulps." Diss., Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/5884.
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Zysman-Colman, Eli. "The chemical and physical properties of polychalcogens." Thesis, McGill University, 2003. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=84864.
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The optimized synthesis of acyclic dialkoxy disulfides and aromatic polysulfides is described and their physical properties probed. A theoretical survey of dialkoxy disulfides and thionosulfites was undertaken in order to determine the most efficacious method for accurately modeling these compounds. In particular, the origin of the high barrier to rotation in the dialkoxy disulfides was determined to be due to a generalized anomeric effect resulting from two lone pair donations of each sulfur atom into each of their respective sulfur-oxygen antibonding orbitals. The origin of the high rotational barrier was also verified experimentally, in particular with respect to solvent and substituent effects. Complimentary to this thermal process, the decomposition of dialkoxy disulfides was also investigated. It was determined that these compounds decompose under first order kinetics via an initial asymmetric S-O homolytic cleavage. Activation parameters for both of these processes were determined.Theoretical modeling on the relative ground state energies of dialkoxy disulfides is also described. It has been ascertained that the equilibrium position between the two isomers can be influenced by the ring size of the molecule; larger rings promote the dialkoxy disulfide isomer. These modeling studies were successfully corroborated experimentally. Of note is the synthesis of a new 8-membered ring dialkoxy disulfides as well as novel 7-membered ring thionosulfites. These compounds were also confirmed by single X-ray crystallography.
The kinetics of desulfurization of acyclic aromatic tri- and tetrasulfides is described. Tetrasulfides were found to transfer a sulfur atom to triphenylphosphine over ten times faster than their trisulfide analogues.
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Ghassemi, Ali. "Nonparametric geostatistical estimation of soil physical properties." Thesis, McGill University, 1987. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=63904.
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Rhyner, Jakob. "Physical and mathematical properties of quasiperiodic structures /." [S.l.] : [s.n.], 1987. http://e-collection.ethbib.ethz.ch/show?type=diss&nr=8451.
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Churakov, Sergey. "Physical-chemical properties of complex natural fluids." [S.l.] : [s.n.], 2001. http://deposit.ddb.de/cgi-bin/dokserv?idn=962849723.
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Roach, Steven John. "Determination of the physical properties of melts." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2001. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/MQ60491.pdf.
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Zhang, Shu. "Mechanical and physical properties of electrospun nanofibers." NCSU, 2009. http://www.lib.ncsu.edu/theses/available/etd-07102009-165411/.
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The process of electrospinning was utilized to fabricate randomly aigned nylon6 nanofibers and aligned nylon6 nanofibers. Polymer concentration affecting electrospinning was investigated. This parameter was evaluated using degree of crystallinity by differential scanning calorimetry (DSC) as well as visual images produced by scanning electron microscopy (SEM). DSC data demonstrated that more crystals were formed with lower polymer concentrations; SEM images revealed that slimmer fibers were produced by lower concentrations. The mechanical properties of unoriented fibers and aligned fibers were tested on Instron 5544. The result of tensile tests indicated higher Youngâs modulus and tensile strength of aligned nanofibers than that of unaligned fibers. The SEM images at broken edges of fibers illustrated different broken mechanisms of these two forms of nanofibers. The broken mechanism of aligned nanofibers was further confirmed by crystallinity parameters obtained from DSC and fiber diameter shown from SEM images.
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Alves, Luis. "Physical and chemical properties of gold nitride." Thesis, University of Newcastle Upon Tyne, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.512027.
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Alcock, Joseph Patrick. "Mechanical and physical properties of orthodontic archwires." Thesis, University of Bristol, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.492645.
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The aim of this study was to investigate the nanomechanical properties of as received, autoclaved and clinically exposed orthodontic archwires. This study was prospective. The clinical component took place in the Orthodontic department of a district general hospital in Bath. Laboratory tests were performed at Bristol Dental School.
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Pyrzas, S. "Physical properties of eclipsing white dwarf binaries." Thesis, University of Warwick, 2011. http://wrap.warwick.ac.uk/51530/.
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Close binaries containing compact objects come in many different forms, but have one thing in common: their evolution involves at least one common envelope phase and angular momentum losses. However, many aspects of these two fundamental processes are still poorly understood. Ample observational input holds the key to improving our understanding, as only then can theoretical models be properly calibrated and tested. Close binaries containing a white dwarf are perhaps the best-suited class of objects to provide such input, due to their ubiquity. White dwarf binaries that additionally display eclipses are of added interest, as accurate and model-independent determinations of fundamental stellar parameters, such as the masses and radii of the binary components, can only be obtained in such systems. In this thesis, I present a study of eclipsing white dwarf binaries. I identify SDSSJ 0110+1326, SDSSJ 0303+0054, SDSSJ 1210+3347, SDSSJ 1435+3733 and SDSSJ 1548+4057 as new eclipsing, detached, post-common-envelope, white dwarf +M-dwarf binaries. I use follow-up photometric and spectroscopic observations, as well as a light curve fitting technique to measure their orbital periods, and derive the masses, radii and radial velocities of the binary components. These five systems have been identified as part of the first dedicated search for eclipsing post-common-envelope binaries and almost double the existing population. The measurements of the stellar parameters, and others obtained from similar systems, are of great value both for the calibration of the common envelope equations and for testing the mass-radius relations of white dwarfs and low-mass main sequence stars. I also identify HS 2325+8205 as a new eclipsing and very frequently outbursting dwarf nova. Combined constraints from photometric and spectroscopic observations are used to infer the binary and stellar parameters. The combination of eclipses, frequent outbursts, brightness range and high declination make HS 2325+8205 an ideal laboratory for detailed studies of accretion discs and accretion processes in close binaries. Finally I study the cataclysmic variable V455And, in an attempt to verify the presence of non-radial pulsations in the white dwarf primary. This is achieved by analysing ten-years worth of photometric observations using time-series analysis techniques and Fourier transforms. The results are indeed consistent with white dwarf pulsations, although a very complex behaviour of the power spectra is revealed, most likely a result of the rapid rotation of the accreting white dwarf primary.
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Astafyeva, Ksenia. "Physical and acoustical properties of fluorocarbon nanoparticles." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2014. http://tel.archives-ouvertes.fr/tel-00960290.
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In this thesis, acoustical and other physical properties of soft submicron suspensions were investigated in order to provide invaluable clues for their adaptation in theragnostic applications. Two types of dispersions were studied: fluorocarbon droplets stabilised with a polymeric (PLGA, PLGA-PEG) shell or a semifluorinated surfactant (called FTAC) shell. Since preparation of polymeric particles had been already developed, we first studied factors affecting mean diameter, size distribution, and coarsening of emulsions made of FTAC stabilising droplets of various fluorocarbons. Mechanical parameters used for emulsion synthesis and surfactants length were optimised to get the smallest droplets (~200 nm in diameter) that stay mainly submicrometric for several weeks. In addition, a full characterisation of surfactant properties was conducted. Next, for ultrasonic theragnostic purpose, it was necessary to improve our understanding in the mechanisms underlying interactions between ultrasonic waves and particles of a suspension. To do so, ultrasound propagation studies through dilute suspensions were carried out in a large frequency range (3-90 MHz) with subsequent modelling. The model could fit with a good accuracy our experimental data on polymeric particles and reveals information about unknown parameters of the shell: the geometrical parameters (shell thickness) and the viscoelastic parameters of the shell (speed of sound, shear moduli at infinite and zero frequencies, and the relaxation frequency). Therefore, such a model provides the required feedback for tuning the physicochemical parameters of nanoparticles in order to optimize their design.
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Unosson, Johanna. "Physical Properties of Acidic Calcium Phosphate Cements." Doctoral thesis, Uppsala universitet, Tillämpad materialvetenskap, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-233637.
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The gold standard for bone replacement today, autologous bone, suffers from several disadvantages, such as the increased risk of infection due to the need for two surgeries. Degradable synthetic materials with properties similar to bone, such as calcium phosphate cements, are a promising alternative. Calcium phosphate cements are suited for a limited amount of applications and improving their physical properties could extend their use into areas previously not considered possible. For example, cement with increased strength could be used as load bearing support in selected applications. The focus of this thesis is, therefore, on how the physical properties of acidic calcium phosphate cements (brushite cements) are affected by compositional variations, with the ultimate aim of making it possible to formulate brushite cements with desired properties. In this thesis a method to measure the porosity of a cement was developed. This method is advantageous over existing methods as it is easy to use, requiring no advanced equipment. A model estimating the porosity of the hardened cement from the initial chemical composition was further formulated and the accuracy affirmed. Utilization of this model allows the porosity to be optimized by calculations rather than extensive laboratory work. The effect on strength and porosity of several compositional variations were also assessed and it was found that the optimal composition to achieve a high strength was: monocalcium phosphate particles in sizes <75µm, 10 mol% excess of beta-tricalcium phosphate, 1 wt% disodium dihydrogen pyrophosphate, and 0.5 M citric acid in a liquid-to-powder ratio of 0.22 ml/g. This composition gave the highest compressive strength historically measured for this type of cement, i.e., 74.4 (±10.7) MPa. Although such a high strength may not be necessary for all applications, it allows for the use of brushite cements in new applications. Furthermore, a high strength of the bulk allows for alterations to the cement that cause a decrease in strength. One application is fast degrading materials, allowing rapid bone ingrowth. A fast degradation is obtained with a high macroporosity, which would reduce strength. The high strength composition was therefore utilized to achieve brushite cement with a high macroporosity.
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Torres, Jesus Cirre. "Thermo physical properties of investment casting waxes." Thesis, University of Birmingham, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.410856.
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Kagawa, Yasuyuki. "New tetracyanoquinodimethane chromophores, synthesis and physical properties." Thesis, Durham University, 1998. http://etheses.dur.ac.uk/4902/.
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Synthesis and physical characterizations of a novel class of zwitterionic organic chromophores were carried out. A series of tetracyanoquinodimethane (TCNQ) derivatives was prepared from reactions with primary and secondary amines. By modifications of the structure it was hoped to optimize their nonlinear properties. The newly synthesized organic chromophores were highly polar, zwitterionic and transparent at wavelengths above 600nm, which is a requirement for waveguide devices at 650nm. The molecular dipole moments were determined experimentally and theoretically. The experimental dipole moments and the theoretical dipole moments were found to be in agreement. The nonlinear optical properties of the new compounds were studied using the Kurtz powder technique. Large second harmonic generation was observed from 7-(2,6, dimethylmorpholino)-7-(4-methylpiperidine)- 8,8-dicyanoquinomethane (25 times urea) as a result of the noncentrosymmetric crystal lattice (P2(_1)2(_1)2(_1)). A large twist between the donor moieties and the benzene ring was found from the crystallographic data, and compared with a theoretical model using an ab initio calculation. Strong fluorescence was observed in the solid states and glass forming solvents at low temperatures. An increase of the quantum yields as a function of viscosity was observed due to the constraining effect of the environment. Variations in the quantum yields from chromophore doped polymeric matrices such as PMMA at room temperature and at low temperature are attributed to the different "free volume" of the polymeric matrices. Possible mechanisms for the emission process in either viscous or non-viscous media are proposed. Photodegradation in solution was observed for illumination by a white light source. In parallel studies photodegradation in PMMA films was observed both in air and under vacuum. A possible photodegradation mechanism via free radicals, compatible with these experimental observations is suggested.
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Haws, Christine Margaret. "Selected physical properties of liquid crystalline polysiloxanes." Thesis, Durham University, 1989. http://etheses.dur.ac.uk/6496/.
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The static and dynamic electrical behaviour, the electrical conductivity, the macroscopic viscosity and the optical transmission characteristics of side chain polysiloxane liquid crystal polymers (LCPs) have been studied. Particular emphasis has been placed on the study of the molecular dynamics using dielectric relaxation spectroscopy and the low field (AC) and high field (DC) conductivity, with the intention of relating structural variations to the behaviour of these materials, and of identifying the most appropriate LCPs for use in practical optical storage devices. The effect on the molecular dynamics of the polymer backbone and the core, spacer and end groups of the mesogenic units was investigated. The LCP responses were shown to be broadly similar to those of low molar mass liquid crystals, though with longer relaxation times. The dynamic responses of structurally different LCPs were shown to be related when these were observed at a temperature referenced to the glass transition temperature. Values of the static permittivity of several LCPs have also been measured and tabulated. Low field electrical conductivity measurements were used to show that the magnitude of the conductivity was comparable to that of commercial liquid crystals. A method was identified whereby the conductivity of different LCPs could be compared. The texture of the measuring electrode surface was found to play an important role in determining the impedance of electrical double layers formed near the surface of the sample, with smooth polymer based surfactants reducing the formation of space charge. High field DC conductivity measurements showed that Schottky-type charge emission occurred at the electrodes at elevated temperatures, except when the smooth polymer based surfactants were present. This was probably a result of the reduction in the local field near the electrode due to a better physical match at the LCP/surfactant interface. The bulk viscosity of mixtures of an LCP and commercial liquid crystal were also measured and the results extrapolated to the viscosity of the LCP. The relationship between electrical conductivity and bulk viscosity was examined. The optical absorption spectra of blue pleochroic dyes have been measured to identify appropriate dyes for use with LCPs in laser written optical memories. The stability of the alignment of selected LCPs with time and temperature was also observed optically.
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Finn, A. "The physical properties of chemically modified catalases." Thesis, University of Manchester, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.377465.
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Clarke, Nicola Zoe. "Physical properties of thiol stabilised gold nanoparticles." Thesis, University of Liverpool, 2002. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.269570.
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Han, Liqing. "Physical and sensory properties of oat cakes /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p1418026.
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Akella, Ravi Chandra. "Information flow properties for cyber-physical systems." Diss., Rolla, Mo. : Missouri University of Science and Technology, 2009. http://scholarsmine.mst.edu/thesis/pdf/Akella_09007dcc806406a3.pdf.
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Thesis (M.S.)--Missouri University of Science and Technology, 2009.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed April 15, 2009) Includes bibliographical references (p. 34-36).
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Dimov, Dimitar. "Fundamental physical properties of graphene reinforced concrete." Thesis, University of Exeter, 2018. http://hdl.handle.net/10871/34648.
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The global warming has increased with unprecedented levels during the last couple of decades and the trend is uprising. The construction industry is responsible for nearly 10% of all carbon emissions, mainly due to the increasing global population and the large demand for housing and civil infrastructure. Concrete, which is the most used construction material worldwide, is found in every type of building as it provides long term structural stability, support and its main constituent cement, is very cheap. Consequently, due to the raising concerns of high average temperatures, the research community started investigating new, innovative methods for substituting cement with 'greener' materials whilst at the same time improving the intrinsic properties of concrete. However, the manufacturing complications and logistics of these materials make them unfavourable for industrial applications. A novel and truly revolutionary method of enhancing the performance of concrete, thus allowing for decreased consumption of raw materials, lies in nanoengineering the cement crystals responsible for the development of all mechanical properties of concrete. Graphene, a two-dimensional sheet of carbon atoms arranged in a hexagonal lattice, is the most promising nanomaterial for composites' reinforcement to this date, due to it's exceptional strength, ability to retain original shape after strain, water impermeability properties and non-hazardous large scale manufacturing techniques. I chose to investigate the addition of liquid-phase exfoliated graphene suspensions for concrete reinforcement, aiming to improve the fundamental mechanical properties of the construction material and therefore allowing the industry to design buildings using less volume of base materials. First, the method of liquid exfoliation of graphene was developed and the resulting water suspensions were fully characterised by Raman spectroscopy. Then, concrete samples were prepared according to British standards for construction and tested for various properties such as compressive and flexural strength, cyclic loading, water impermeability and heat transport. A separate, in-depth, study was carried out to understand the formation and propagation of micro-structural cracks between the concrete's internal matrix planes, and graphene's impact on total fracture capacity and resistance of concrete. Lastly, multiple experiments were performed to investigate the microcrystallinity of cement hydration products using X-Ray diffraction. In general, all experimental results show a consistent improvement in concrete's performance when enhanced with graphene on the nanoscale level. The nanomaterial improves the mechanical interlocking of cement crystal, thus strengthening the internal bonds of the composite matrix. This cheap and highly scalable method for producing and mixing graphene with concrete turns it into the first truly applicable method for industrial applications, with a real potential to have positive impact on the global warming by decreasing the production of concrete.
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Chilton, John Andrew. "Physical properties of selected heavy fermion systems." Thesis, Imperial College London, 1989. http://hdl.handle.net/10044/1/47379.
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Croft, Oliver. "Manganites : physical properties and magnetic tunnel devices." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.709185.
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Ward, Daniel W. "Tailoring the physical properties of energetic materials." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/29531.
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Energetic materials are a class of material that have large amounts of chemical energy stored within their molecular structure. This energy is released upon decomposition, generally in the form of rapidly expanding, hot gases. They are therefore used for a wide range of applications such as; mining, military, and space exploration, and there is therefore a strong desire to improve the overall performance and safety of such materials. On account of reduced sensitivity to initiation by shock and impact, 2,4-dinitroanisole (DNAN) is a potential replacement for 2,4,6-trinitrotoluene (TNT) in melt-cast formulations for military applications. However, up to 15 % irreversible growth of DNAN has been previously observed upon thermal cycling and is a key reason why DNAN has not yet been universally accepted as a replacement for TNT. DNAN exhibits a complex system of polymorphism. One particular transition from DNAN-II to DNAN-III, which occurs at 266 K, has been observed in these studies to cause 8 - 10 % growth of DNAN-II pellets when temperature cycled for 30 cycles between 256 K and 276 K. What was even more concerning was the appearance of cracking of DNAN pellets after being temperature cycled. Doping the crystal structure of DNAN-II with related molecules, such as 2,4-dinitrotoluene or 2,4-dinitroaniline, was investigated in order to probe how steric and electronic factors affect the transition. The addition of varying amounts of 2,4-dinitroaniline suppressed this transition to varying extents and ultimately as low as 150 K with 10 mol% 2,4-dinitroaniline, and potentially eliminated entirely. This doped material has been designated as phase-stabilised DNAN (PS-DNAN). Temperature cycling of PS-DNAN was conducted over the same 256-276 K range, and this material showed no evidence of irreversible growth compared to undoped DNAN pellets, on account of suppression of the II-III transition. The production of PS-DNAN is therefore a possible route to avoiding problematic irreversible growth in DNAN formulations. Melt-casting of DNAN in a sealed environment consistently results in the metastable form-II, which has proven to be stable for in excess of 32 weeks. However, exposure to seeds of form-I, either via deliberate or accidental seeding, rapidly converted the material to the thermodynamically more stable form-I. This transition was accelerated by increasing temperature which rapidly converted pellets of DNAN-II to DNAN-I. When DNAN-I pellets were temperature cycled, they did not undergo a transition to form-III, and as a result did not illustrate irreversible growth. This presents another approach to avoiding problematic growth in DNAN-based materials. Whilst being one of the most widely used oxidisers in propellant formulations, ammonium perchlorate (AP) has several issues; the formation of porous ammonium perchlorate (PAP) can seriously affect the sensitivity of propellants, the hygroscopicity of AP makes handling and manufacture of formulations difficult, and spherical AP exhibits poor binding properties to the polymer binders used in propellant formulations. Several different approaches were taken to combat these issues. Co-crystallisation of AP was attempted in order to produce new AP co-crystals with reduced reactivity towards the formation of PAP. A theoretical based approach using COSMOtherm was used for rapid screening and selection of potential co-formers to be used in lab-based co-crystallisation trials. Co-crystallisation was attempted using multiple stoichiometries and multiple solvents by solvent evaporation, cooling crystallisation, and Resonant Acoustic Mixing methods. Unfortunately no new co-crystals were obtained, presumably on account of the ionic nature of AP which makes co-crystallisation difficult. The mass of untreated AP increased by 0.027% in a humid environment (90% RH) due to the uptake of water, which resulted in significant caking and hence hindering the processability of AP. In an attempt to counteract the hygroscopicity and improve the processability of AP, particles of AP were coated in graphene nanoplatelets using the technique of Resonant Acoustic Mixing. Low mixing energy (G-force) (30 G) resulted in poor coating of AP, but the flowability of this mixure after exposure to moisture was significantly enhanced, most probably as a result of graphene acting as an effective lubricant. Higher mixing energy (90-100 G) was required to break up agglomerates of graphene nanoplatelets and resulted in AP particles efficiently coated with graphene (APGR). Differential scanning calorimetry showed that the energy released upon decomposition of APGR was greater than pure AP, or AP mixed with graphene, due to the intimacy of the AP particle surface and the graphene coating.
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Juri, Juan Ernesto. "Prediction of petro-physical properties for carbonates." Thesis, Heriot-Watt University, 2016. http://hdl.handle.net/10399/3120.
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This thesis is concerned with the inversion of lattice pore-network model parameters of carbonate rocks using only the capillary pressure, and then the use of the inverted parameters to predict the water-flooding relative permeabilities of the carbonate rocks. Background: There has been a tendency to claim that pore-network modelling using three-dimensional micro-computed tomography or 3D mathematically created images can predict imbibition relative permeabilities for wettabilities other than strongly water/oil-wetting. This is based on the flexibility for matching data, which is a weakness of pore-network modelling. The method proposed in this thesis is important because a large percentage of the porosity in carbonates is microporosity. Conclusions: We applied stochastic inversion of lattice pore-network model parameters using Hamiltonian Dynamics (Hamiltonian Monte Carlo) to three carbonate rock samples and we predicted water-flooding relative permeabilities with good accuracy by using as constraint only routinely obtained data, such as mercury intrusion capillary pressure (MICP) and oil/water capillary pressure. We found that there is a strong correlation between the amount of microporosity and the volume exponent parameter. This suggests that when microporosity is ignored, the volume exponent will tend to be systematically strongly underestimated. HMC found large variability in wettability that causes mid-sized pores to be invaded at the same level of pressure as larger pores. The coexistence of these events reduces the tendency for preferential flow through large pores, resulting in more uniform flow at the pore scale compared with the case in which flow is restricted only to large pores. Mid-sized pores have an important effect on the connectivity because they could have higher contact angles than larger pores. Therefore, they do not spontaneously imbibe and shield larger pores, improving water-flooding displacement. The wettability of micropores could better explain the gentle curvature of the imbibition water relative permeability compared with the generally assumed mixed-wet large wettability model. The importance of the maximum and minimum observed capillary pressure is directly connected to accounting for the full pore-size distribution. Thus, the common assumption that microporosity can be ignored is unsatisfactory. The ranges of advancing contact angles obtained from the HMC inversion were wider than the ranges of apparent advancing contact angles obtained with analytical determinations in previous studies, and in one case our results were contradictory to the analytical determination. It follows that variability in advancing and receding contact angles is not reflected in the apparent contact angle data outside porous media. Apparent contact angle data outside porous media cannot completely characterise the wettability in porenetwork models because the data does not capture the contact angle variability in porous media. The existence of wetting films depends on the maximum capillary pressure during drainage, and thus wettability alteration during ageing. Our results suggest that matching both connate water at the maximum drainage capillary pressure before ageing and matching residual oil at the minimum imbibition capillary pressure leads to better estimation of the advancing and receding variability in the contact angles.
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Zhao, Nan. "Evaluation of physical properties of ionic liquids." Thesis, Queen's University Belfast, 2017. https://pure.qub.ac.uk/portal/en/theses/evaluation-of-physical-properties-of-ionic-liquids(8198ab21-0f79-461c-9e4a-6cbb431a3910).html.
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Firstly, experimental data for ionic liquids properties; density, viscosity of pure ionic liquids, viscosity of binary ionic liquid mixtures, and solubility in molecular solvents were collected from the literature and thus four databases were compiled. Then mathematical gnostics was used to analyse the uncertainty and discrepancy of experimental data reported from different resources and to recommend reliable datasets. The volumetric properties of ionic liquids were evaluated by using a group contribution method. The volumetric parameters of 55 ions were calculated by correlating 5,399 training data points using the Tait-type equations. 2,522 test datapoints were used to validate the accuracy of this method. This method also allows the calculation of mechanical coefficients with a good agreement. The viscosity of pure and binary mixtures of ionic liquids was estimated using a new method based on the UNIFAC-VISCO model. The dataset containing 819 experimental viscosity data points for 70 pure ionic liquids was correlated using the modified UNIFAC-VISCO method, thus the interaction parameters and ion VFT parameters were estimated, which were used for the evaluation of 11 types of binary mixtures. A good agreement with the evaluation of binary mixtures in turn proved that the parameters estimated were accurate enough to estimate the viscosity of pure and mixtures ionic liquids. The liquid-liquid-equilibrium data for binary mixtures; ionic liquid and a molecular solvent, were modelled using the UNIQUAC and UNIFAC methods. A user-friendly web based interface was established and all the mutual solubility data between the ionic liquid and molecular solvents were uploaded to the online database, which allows end user to get reference data in academy and industry.
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Yang, Guang. "Structure and physical properties of chalcogenide glasses." Rennes 1, 2012. http://www.theses.fr/2012REN1S027.
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Les verres dits de chalcogénures, synthétisés à partir de S, Se et/ou Te, se présentent sous forme de blocs opaques à la lumière visible, mais sont par contre transparents dans l'infrarouge. Ils possèdent d'intéressantes propriétés thermo-mécaniques qui permettent de les mettre sous forme de fibres optiques, de guides planaires ou de lentilles. La contrepartie de ces propriétés exceptionnelles réside dans leurs basses températures caractéristiques et surtout dans une tenue en service qui n'égale pas celle des verres d'oxydes. L'objet de ce travail consiste à chercher à mieux comprendre l'origine de ces comportements en corrélant l'évolution des propriétés structurales d'une part et thermo-mécaniques d'autre part. Pour cela, nous nous sommes appuyés sur deux familles de verres binaires modèles: AsₓSe₁₋ₓ et GeₓSe₁₋ₓ. Pour ces 2 familles, l'ensemble des propriétés thermiques et mécaniques a été mesuré permettant ainsi de suivre leurs évolutions sur une gamme de compositions la plus large jamais obtenue. Des études structurales menées par RMN et Raman conduisent à des corrélations permettant de mieux comprendre les origines structurales des propriétés de ces verres. Ensuite, nous nous sommes intéressés aux comportements de fibres optiques fabriquées à partir de verre dont la formulation est aboutie. Ainsi, une caractérisationcomplètede l'évolution de la viscosité au cours du fibrage a été effectuée in-situ à partir d'un verre de composition As₂Se₃. Enfin, un suivi des effets du vieillissement sur les propriétés mécaniques de fibres en verre de composition Te₂As₃Se₅est proposéThis work aims at contributing to refine the structural properties of two simple glassy systems, AsₓSe₁₋ₓ and GeₓSe₁₋ₓ families. Although a lot of insightful research has been done on these glass models, their structural descriptions are still controversial. To achieve our goal, a large set of physical and structural properties was recorded on a same series of glassy samples for each family. The composition dependence of physical properties exhibit an extremum at = 2. 4 in AsxSe1-x glassy system. These results indicates a dramatic structural change at x = 0. 4, which evolves from a pyramidal network in Se-rich region and then transitions to a lower dimension structure containing an increasing number of 0-D molecular inclusions in As-rich region. Moreover, a series of physical properties throughout and above the glass transition, shows a double minimum at =2. 3 and =2. 5 with a local maximum at =2. 4. The observed trend is in agreement with the dimensionality of the network derived from structural data obtained by NMR. In binary GexSe1-x glasses, our results also indicates a dramatic structural change at x = 1/3. For the Ge-rich region, they do not support the tetrahedral model but strongly suggests that the Ge-rich glass network is closer to the GeSe crystalline phase structure. On the other hand, the viscosity of As₂Se₃ glass within the hot-zone region of the fiber drawing process was estimated using the actual temperature distribution and from standard continuum mechanics equations for a linear viscous material. Effect of ageing conditions (ageing in dark, in light and under load) on mechanical property of Te₂As₃Se₅ glass fibers has been investigated
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Rigas, Konstantinos. "Thermal Physical Properties of Söderberg Electrode Material." Thesis, KTH, Materialvetenskap, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-259191.
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Söderberg electrodes take part in the production of ferroalloys, copper, nickel, platinum, and calcium carbide. They are involved in a continuous and with low costs operation. The study of such electrodes is essential, since research and new findings will provide us with vital information regarding the operation of such furnaces leading to a more efficient production. Therefore, the study of Söderberg electrodes materials characteristics is of great importance. The current work refers to the thermal properties of Söderberg electrode paste by focusing on the thermal conductivity coefficient from room temperature up to 800 °C with the Transient Plane Source (TPS) method applied to an electrode paste material with softening point at 65°C. Another electrode paste with higher softening point at 90 °C and an already baked material are studied to some extent. The study gives significant results for the thermal conductivity coefficient for all the investigated cases. Results indicate variation of coefficients regarding the phase evolved during heating at different temperatures. In principle, thermal conductivity of the green paste with low softening point decreases until 400°C and increases after the baking point which is found in between 400-500°C. A few measurements for the green paste with higher softening point indicate the same trend. For the case of the fully baked electrode, thermal conductivity seems to keep an increasing trend according to temperature increase. On the two last mentioned materials, more experimental work will be conducted in future.Söderberg-elektroder används till produktionen av ferrolegeringar, koppar, nickel, platina och kalciumkarbider. De är involverade i kontinuerliga och lågkostnadsoperationer. Studien av sådana elektroder är väsentlig eftersom forskning och nya fynd kommer att ge oss viktig information om driften av sådana ugnar vilket leder till en effektivare produktion. Därför är studien av Söderberg-elektrodens materialegenskaper av stor betydelse. Det nuvarande arbetet refererar till de termiska egenskaperna hos Söderberg-elektrodpastan genom att fokusera på den termiska konduktivitetskoefficienten från rumstemperatur upp till 800°C med den TPS-metoden (Transient Plane Source) tillämpad på ett elektrodpasta-material med en mjukningspunkt vid 65°C. En annan elektrodpasta med en högre mjukningspunkt vid 90°C samt ett redan bakat material studeras även till viss del. Studien ger signifikanta resultat för värmeledningsförmågan för alla undersökta fall. Resultaten indikerar på variationer av koefficienterna gällande fasen som utvecklas under uppvärmning vid olika temperaturer. I stort sett minskar värmeledningsförmågan hos den gröna pastan med låg mjukningspunkt upp till 400°C och ökar efter bakningspunkten som finns mellan 400-500°C. Några mätningar för den gröna pastan med en högre mjukningspunkt visar samma trend. När det gäller den helt bakade elektroden verkar värmdeledningsförmågan hålla en ökande trend beroende på temeperaturökningen. På de två sistnämnda materialen kommer mer experimentellt arbete att genomföras i framtiden.
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Τσαμπά, Αρετή. "Φυσικές και μηχανικές ιδιότητες γρανιτών περιοχής Φλώρινας Ι." Thesis, 2013. http://hdl.handle.net/10889/6497.
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Τα δείγματα που μελετήθηκαν στην παρούσα διπλωματική εργασία προέρχονται από τη θέση Τούμπα - Ανθοβούνι, στις ΒΔ-Δ-ΝΔ υπώρειες του όρους Βαρνούντα του νομού Φλώρινας. Στην περιοχή αυτή κατασκευάστηκε Αιολικό Πάρκο, όπου πραγματοποιήθηκαν συνολικά τριάντα τέσσερις γεωτρήσεις για την εγκατάσταση ανεμογεννητριών. Η ευρύτερη περιοχή τη Φλώρινας ανήκει γεωλογικά στην Πελαγονική Ζώνη και δομείται γενικά από γνευσίους και ημι-μεταμορφωμένα πετρώματα.
Στα πλαίσια αυτής της εργασίας εκτελέστηκαν εργαστηριακές δοκιμές σε δείγματα βραχωδών σχηματισμών. Στο τρίτο κεφάλαιο περιγράφονται αναλυτικά οι δοκιμές που χρησιμοποιήθηκαν. Μετά τη συλλογή τους, τα βραχώδη δείγματα διαμορφώθηκαν σε κυλινδρικό σχήμα, διαμέτρου 53 mm με εργαστηριακή καροταρία. Τα άκρα των δοκιμίων κόπηκαν σε μήκη ανάλογα των προβλεπόμενων εργαστηριακών δοκιμών. Οι βάσεις τους λειάνθηκαν ώστε να είναι κάθετες προς τον μεγάλο άξονα του δοκιμίου.
Στο επόμενο κεφάλαιο αναφέρεται η δειγματοληψία των γρανιτών. Η θέση δειγματοληψίας εντοπίζεται στην περιοχή Πισοδερίου, που βρίσκεται στο νομό Φλώρινας. Επίσης, στην ενότητα αυτή περιγράφονται και οι δύο τρόποι διαμόρφωσης των δειγμάτων μετά από τη δειγματοληψία με το δειγματοληπτικό γεωτρύπανο.
Στο εργαστήριο εξετάστηκαν τα φυσικά και τα μηχανικά χαρακτηριστικά των γρανιτών. Οι εργαστηριακές αυτές δοκιμές βραχομηχανικής γίνονται για τον προσδιορισμό της πυκνότητας, του λόγου κενών, του πορώδους, και της αντοχής των γρανιτών σε μοναξονική ανεμπόδιστη θλίψη. Στο κεφάλαιο αυτό, τα αποτελέσματα από κάθε εργαστηριακή δοκιμή προβάλλονται σε πίνακες, καθένας από τους πίνακες αυτούς αναφέρεται και σε μία άλλη δοκιμή. Ο αριθμός των δοκίμια που χρησιμοποιήθηκαν για κάθε δοκιμή είναι ο εξής: για τον προσδιορισμός των φυσικών παραμέτρων οκτώ (8) δοκίμια, για τον προσδιορισμός των δυναμικών παραμέτρων έξι (6) δοκίμια και για τον προσδιορισμός των παραμέτρων αντοχής χρειάστηκαν δέκα (10) δοκίμια.
Στο έκτο κεφάλαιο συγκεντρώνονται σε ένα πίνακα όλα τα αποτελέσματα από όλες τις δοκιμές που εκτελέστηκαν. Οι δοκιμές αυτές πραγματοποιήθηκαν στους γνεύσιους, γρανίτες και γρανιτογνεύσιους.The samples that have been studied in the current diplomatic project come from Toumpa-Anthovouni, at the NW-W-SW foot of the mountain Varnouda of county Florina. At these area was built a wind park, where had taken place thirty-four drilling for the installing of the wind turbines. The wider area of Florina geologically belongs to the Pelagonian zone and is generally structured by gneisses semi-transformed stones. Within the project laboratory testing have taken place on samples of rock formations. In the third chapter the testing that were used are described in depth. After their collection, the rock samples were reformed into cylindrical shape, diameter 53mm by laboratory karotaria. The ends of the samples were cut into lengths as the planned laboratory tests. Their bases were planished to be perpendicular to the long axis of the specimen. In the next chapter the sampling of the granites are mentioned. The place of the sampling is located in the area of Pisoderio, which belongs to the county Florina. Also, on that section both two ways of forming the samples after the sampling by sampling rig are described. At the laboratory the natural and mechanical characteristics of the granites were examined. These laboratory tests on rock mechanics have been done for the determination of the density, the ratio of spaces, the porosity and the durability of the granites under uniaxial unconfined compression. In this chapter, the results from each laboratory test are displayed on tables, each one of them mentions a different test. The number of the samples that were used for each test are the following; for the determination of the natural parameters eight (8) samples, for the determination of the dynamic parameters six (6) samples and for the determination of the durability parameters were used ten (10) samples. In the sixth chapter all the results from all the tests that have been executed are gathered in one table. These tests took place in gneiss and granites.