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11	Colligative Measurements in Anhydrous Hydrogen Fluoride. Humphreys, David Alan 09 1900 (has links) <p> Techniques have been developed for making cryoscopic and vapour pressure measurements in anhydrous hydrogen fluoride. The cryoscopic constant for the solvent has been determined. </p> <p> The techniques developed have been used to determine the mode and extent of the ionization of some acids and bases of the HF system. The formation and stability of polymeric ions in the solvent has been investigated and the formation of the previously unknown anion As₂F₁₁⁻ has been shown. Cryoscopy has been used to detect a new polymeric 1:1 adduct of XeF₂ and SbF₅. Solutions of cyanides in HF have been investigated and the formation of a new polymeric cation Hg₂CN₃⁺, formed when mercury cyanide dissolves in HF, has been suggested. The results of some experiments on solvolysis reactions are also reported. </p> / Thesis / Doctor of Philosophy (PhD) chemistry colligative measurements anhydrous hydrogen fluoride; HF cryoscopic; cryoscopic constant vapour pressure solvolysis reaction
12	Riskmoment vid släckning av brand i litium-jonbatterier ombord på fartyg / Hazards regarding extinguishing of lithium-ionbattery fires onboard ships Lif, William, Sehlin, André January 2020 (has links) Detta arbete söker att svara på vilka risker som måste beaktas vid bekämpningen av en brand i litium-jonbatterier ombord på fartyg. Antalet elbilar med denna typ av batterier ökar i popularitet och transporteras ofta via fartyg. För att få svar på vilka risker som då uppstår och hur de ska beaktas, har en serie semistrukturerade intervjuer genomförts med räddningstjänsten i olika län, samt forskare som har kunskap inom ämnet. Arbetet har visat på att det finns flera olika risker som kan uppkomma med ett litium-jonbatteri, brand och termisk rusning är några av riskerna som kan uppkomma. Vid dessa händelser släpps ett flertal farliga gaser ut där den mest kända är vätefluorid. Andra risker som uppkommer varierar mellan den höga värmen av 1150°C från branden, till det faktum att en sådan brand inte kan kvävas då den förser sig själv med syre vilket gör att den kan fortsätta brinna. Det finns inga tydliga regelverk eller riktlinjer för hur dessa bränder ska bekämpas på bästa sätt och detta kräver ytterligare forskning för att tydliggöra hur brand i litium-jonbatterier skall hanteras. / This study is searching for the answer of what hazards must be considered when fighting fires in lithium-ion batteries on board ships. The number of electric vehicles with this type of battery are increasing in popularity and are often transported through the shipping industry. To highlight the hazards and how to handle them, a couple of semi-structured interviews were conducted with firefighters and researchers with knowledge in the subject. The study has looked at the risks that arise when a lithium-ion battery has a thermal runaway, during which several dangerous gases are emitted where the most known is hydrogen fluoride. Other hazards that arise vary from high heat at points as high as 1150° C, to the fact that such fire cannot be suffocated as it is selfsufficient in oxygen. There are no clear regulations or guidelines on how to fight this kind of fire and further research is required to clarify how to handle these types of fires. Lithium-ionbatteries hydrogen fluoride firefighting techniques battery fires risks hazards Litium-jonbatterier vätefluorid brandsläckningsteknik batteribrand risker Övrig annan teknik
13	Släckning av brand i elbilar ombord på fartyg : För ett säkert och effektivt släckarbete av elfordon ombord på fartyg / Extinguishing of fires in electric cars on board ships : For safe and efficient extinguishing of electric vehicles on board ships Berglin, Anton, Lindroth, Tobias January 2022 (has links) Målet med arbetet var att undersöka vilka tekniker som finns för att bekämpa bränder i elbilar ombord på fartyg och vilka farliga gaser som elbilar med litiumjonbatterier avger när de brinner. För att svara på dessa gjordes en metaanalys för att undersöka hälsoriskerna med några av de farliga gaserna som uppstår, hur man minskar hälsorisken som följer bränder i litiumjonbatteri genom användning av särskild utrustning, samt vilka åtgärder som går att utnyttja ombord på fartyg, Litiumjonbatterier har även visats sig problematiska att släcka, men det har dykt upp särskilda släckmedel för att bekämpa dessa bränder. I arbetet undersöks några av dessa släckmedel. Då teknologin bakom batteridrift i fordon fortfarande är relativt ny och precis börjar bli vanligt på våra gator, så finns det ännu inte mycket direktiv om vilka åtgärder som bör tas för en effektiv släckning, förhindra återtändning och skydda personers hälsa ombord på fartyg. Därför har vi valt att titta på vilka rutiner det finns i land för att se om de går att tillämpa ombord. / The purpose of this thesis was to examine which techniques exists to fight fires in electrical vehicles aboard ships and which harmful substances electrical vehicles releases when burning. To answer these questions, we performed a meta-analysis to understand some of the harmful gases that will be present during an EV fire, how to minimize the health hazard that comes with fires in lithium-ion batteries using certain equipment and what measures that can be taken aboard ships. Li-ion batteries have also proven to be problematic to extinguish, but there have emerged certain extinguishing agents to fight these types of fires. In this thesis we look at some of these extinguishing agents. As technology being used in battery powered vehicles is still new and just becoming common on our streets, there is not a whole lot of directives on how to be effective in extinguishing them, prevent reignition and protect the health of people abord ships. That is why we have chosen to look at what is being used on shore and see if it can be applied on ships. Marine Engineer Electric vehicles Fire lithium-ion battery hydrogen fluoride Fire extinguishing techniques Thermal Runaway Sjöingenjör; Elbilar Brand litiumjonbatteri vätefluorid Brandsläckningstekniker Termiskrusning Övrig annan teknik
14	Advanced electronic structure theory: from molecules to crystals / Höhere Elektronenstrukturtheorie: vom Molekül zum Kristall Buth, Christian 21 October 2005 (has links) (PDF) In dieser Dissertation werden ab initio Theorien zur Beschreibung der Zustände von perfekten halbleitenden und nichtleitenden Kristallen, unter Berücksichtigung elektronischer Korrelationen, abgeleitet und angewandt. Als Ausgangsbasis dient hierzu die Hartree-Fock Approximation in Verbindung mit Wannier-Orbitalen. Darauf aufbauend studiere ich zunächst in Teil I der Abhandlung den Grundzustand der wasserstoffbrückengebundenen Fluorwasserstoff und Chlorwasserstoff zick-zack Ketten und analysiere die langreichweitigen Korrelationsbeiträge. Dabei mache ich die Basissatzextrapolationstechniken, die für kleine Moleküle entwickelt wurden, zur Berechnung von hochgenauen Bindungsenergien von Kristallen nutzbar. In Teil II der Arbeit leite ich zunächst eine quantenfeldtheoretische ab initio Beschreibung von Elektroneneinfangzuständen und Lochzuständen in Kristallen her. Grundlage hierbei ist das etablierte algebraische diagrammatische Konstruktionsschema (ADC) zur Approximation der Selbstenergie für die Bestimmung der Vielteilchen-Green's-Funktion mittels der Dyson-Gleichung. Die volle Translationssymmetrie des Problems wird hierbei beachtet und die Lokalität elektronischer Korrelationen ausgenutzt. Das resultierende Schema wird Kristallorbital-ADC (CO-ADC) genannt. Ich berechne damit die Quasiteilchenbandstruktur einer Fluorwasserstoffkette und eines Lithiumfluoridkristalls. In beiden Fällen erhalte ich eine sehr gute Übereinstimmung zwischen meinen Resultaten und den Ergebnissen aus anderen Methoden. / In this dissertation, theories for the ab initio description of the states of perfect semiconducting and insulating crystals are derived and applied. Electron correlations are treated thoroughly based on the Hartree-Fock approximation formulated in terms of Wannier orbitals. In part I of the treatise, I study the ground state of hydrogen-bonded hydrogen fluoride and hydrogen chloride zig-zag chains. I analyse the long-range contributions of electron correlations. Thereby, I employ basis set extrapolation techniques, which have originally been developed for small molecules, to also obtain highly accurate binding energies of crystals. In part II of the thesis, I devise an ab initio description of the electron attachment and electron removal states of crystals using methods of quantum field theory. I harness the well-established algebraic diagrammatic construction scheme (ADC) to approximate the self-energy, used in conjunction with the Dyson equation, to determine the many-particle Green's function for crystals. Thereby, the translational symmetry of the problem and the locality of electron correlations are fully exploited. The resulting scheme is termed crystal orbital ADC (CO-ADC). It is applied to obtain the quasiparticle band structure of a hydrogen fluoride chain and a lithium fluoride crystal. In both cases, a very good agreement of my results to those determined with other methods is observed. Ab-initio-Rechnung Angeregte Zustände Bandstruktur Basissatz Extrapolation Basissatz Konvergenz Bindungsenergie Chlorwasserstoff Elektronenstrukturtheorie Elektronische Korrelation Fluorwasserstoff Greensfunktion Kristall Lithiumfluorid Propa Green's function ab initio calculations band structure basis set convergence basis set extrapolation binding energy crystal electron correlation electronic structure theory excited states hydrogen chloride hydrogen fluoride infinite bent chain ddc:530 rvk:UM 1200 Ab-initio-Rechnung Angeregter Zustand Bandstruktur Bindungsenergie Chlorwasserstoff Elektronenkorrelation Extrapolation Fluorwasserstoff Green-Funktion Konvergenz Kristall Lithiumfluorid Propagator Vielteilchentheorie
15	Advanced electronic structure theory: from molecules to crystals Buth, Christian 10 November 2005 (has links) In dieser Dissertation werden ab initio Theorien zur Beschreibung der Zustände von perfekten halbleitenden und nichtleitenden Kristallen, unter Berücksichtigung elektronischer Korrelationen, abgeleitet und angewandt. Als Ausgangsbasis dient hierzu die Hartree-Fock Approximation in Verbindung mit Wannier-Orbitalen. Darauf aufbauend studiere ich zunächst in Teil I der Abhandlung den Grundzustand der wasserstoffbrückengebundenen Fluorwasserstoff und Chlorwasserstoff zick-zack Ketten und analysiere die langreichweitigen Korrelationsbeiträge. Dabei mache ich die Basissatzextrapolationstechniken, die für kleine Moleküle entwickelt wurden, zur Berechnung von hochgenauen Bindungsenergien von Kristallen nutzbar. In Teil II der Arbeit leite ich zunächst eine quantenfeldtheoretische ab initio Beschreibung von Elektroneneinfangzuständen und Lochzuständen in Kristallen her. Grundlage hierbei ist das etablierte algebraische diagrammatische Konstruktionsschema (ADC) zur Approximation der Selbstenergie für die Bestimmung der Vielteilchen-Green's-Funktion mittels der Dyson-Gleichung. Die volle Translationssymmetrie des Problems wird hierbei beachtet und die Lokalität elektronischer Korrelationen ausgenutzt. Das resultierende Schema wird Kristallorbital-ADC (CO-ADC) genannt. Ich berechne damit die Quasiteilchenbandstruktur einer Fluorwasserstoffkette und eines Lithiumfluoridkristalls. In beiden Fällen erhalte ich eine sehr gute Übereinstimmung zwischen meinen Resultaten und den Ergebnissen aus anderen Methoden. / In this dissertation, theories for the ab initio description of the states of perfect semiconducting and insulating crystals are derived and applied. Electron correlations are treated thoroughly based on the Hartree-Fock approximation formulated in terms of Wannier orbitals. In part I of the treatise, I study the ground state of hydrogen-bonded hydrogen fluoride and hydrogen chloride zig-zag chains. I analyse the long-range contributions of electron correlations. Thereby, I employ basis set extrapolation techniques, which have originally been developed for small molecules, to also obtain highly accurate binding energies of crystals. In part II of the thesis, I devise an ab initio description of the electron attachment and electron removal states of crystals using methods of quantum field theory. I harness the well-established algebraic diagrammatic construction scheme (ADC) to approximate the self-energy, used in conjunction with the Dyson equation, to determine the many-particle Green's function for crystals. Thereby, the translational symmetry of the problem and the locality of electron correlations are fully exploited. The resulting scheme is termed crystal orbital ADC (CO-ADC). It is applied to obtain the quasiparticle band structure of a hydrogen fluoride chain and a lithium fluoride crystal. In both cases, a very good agreement of my results to those determined with other methods is observed. info:eu-repo/classification/ddc/530 ddc:530

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