O presente trabalho avaliou, por microscopia eletrônica de varredura (MEV), a limpeza das paredes dos canais radiculares instrumentados pelas técnicas rotatória e Self-adjusting file (SAF®) com uso do NaOCl a 1% como solução irrigadora e o uso do EDTA a 15% e da Quitosana 0,20% como soluções quelantes, e quantificou os íons cálcio removidos pelas diferentes soluções irrigadoras por meio de espectrometria de absorção atômica. Trinta dentes caninos inferiores humanos foram divididos em dois grupos (n=15), de acordo com a técnica de instrumentação utilizada: A - instrumentos FlexMaster® usados na técnica Free Tip Preparation, assegurado alargamento mínimo de 200, até o instrumento # 60.02, irrigados com 1 mL de NaOCl 1% em cada troca de instrumento e B - sistema SAF®, com prévio alargamento manual até o instrumento K #20, aplicação da SAF® por 4 minutos, com fluxo de irrigação pelo sistema VATEA de 5mL/min. Os dentes foram divididos em três subgrupos conforme a irrigação final: G1-NaOCl 1%, G2- EDTA 15% e G3 Quitosana 0,20%. Utilizou-se 5mL de cada solução à 1mL/min. A solução extravasada pelo forame foi coletada e submetida à análise espectrométrica. O EDTA 15% apresentou maior capacidade de remoção de íons cálcio do que a Quitosana a 0,20% (p<0,05) e o NaOCl 1% não removeu íons. Os espécimes foram analisados em MEV. As fotomicrografias obtidas foram avaliadas qualitativamente em relação à remoção da camada de smear observada. Não houve diferença entre as instrumentações rotatória e SAF® nos terços dos canais avaliados. Analisadas as interações entre as técnicas utilizadas e aos terços do canal, o EDTA 15% apresentou melhores resultados que a Quitosana 0,20% (p<0,05), sendo ambas as soluções melhores que o NaOCl 1%. Conclui-se que as soluções quelantes testadas foram capazes de remover íons cálcio das paredes dos canais radiculares - com superioridade do EDTA 15% sobre a Quitosana 0,20%, e o NaOCl a 1% não apresentou essa capacidade - e removeram a camada de smear das paredes dos canais radiculares com superioridade do EDTA 15%, sem interferência das técnicas de instrumentação avaliadas rotatória e SAF®. / The present study evaluated, by scanning electron microscopy (SEM), the cleanness of the root canal walls instrumented by rotary and the self-adjusting file (SAF®) techniques using 1% NaOCl as an irrigating solution and 15% EDTA, 0.20% Chitosan as chelator solutions, and quantified the calcium ions removed by the different irrigants with atomic absorption spectrometry. Thirty human mandibular canine teeth were divided into 2 groups (n=15) according to the instrumentation technique used: A- FlexMaster® instruments used with the Free tip Preparation, assuring a minimal enlargement of 200m, up to a #60 .02 instrument, irrigated with 1mL of 1% NaOCl between each instrument; and B- SAF® system, with previous enlargement to a type K #20 manual instrument, application of SAF during 4 minutes, with VATEA irrigation system at a flow of 5mL/min. The teeth were divided into three subgroups according to the final irrigation protocol: G1- 1% NaOCl, G2- 15% EDTA and G3- 0.20 % Chitosan. Five mL of solution were used at 1mL/min. The solution extruded thru the foramen was collected and submitted to spectrometric analysis. 15% EDTA showed higher calcium ion removal capacity then 0.20% Chitosan (p<0.05) and the 1% NaOCl did not remove ions. The specimens were evaluated by means of SEM. The photomicrographs obtained were qualitatively evaluated in terms of smear layer removal. There was no significant difference between the rotary and SAF® instrumentation systems in the evaluated canal thirds. The interaction techniques used and canals thirds showed that the 15% EDTA revealed better results than the 0.02% Chitosan (p<0.05), and both were better than 1% NaOCl. It can be concluded that the tested chelating solutions removed calcium ions from the root canals walls with better results for 15% EDTA than 0.20% Chitosan; 1% NaOCl did not present this capacity - and removed the smear layer form the root canal walls with better results for 15% EDTA, with no difference between the evaluated techniques rotary and SAF®.

O presente trabalho avaliou, por microscopia eletrônica de varredura (MEV), a limpeza das paredes dos canais radiculares instrumentados pelas técnicas rotatória e Self-adjusting file (SAF®) com uso do NaOCl a 1% como solução irrigadora e o uso do EDTA a 15% e da Quitosana 0,20% como soluções quelantes, e quantificou os íons cálcio removidos pelas diferentes soluções irrigadoras por meio de espectrometria de absorção atômica. Trinta dentes caninos inferiores humanos foram divididos em dois grupos (n=15), de acordo com a técnica de instrumentação utilizada: A - instrumentos FlexMaster® usados na técnica Free Tip Preparation, assegurado alargamento mínimo de 200, até o instrumento # 60.02, irrigados com 1 mL de NaOCl 1% em cada troca de instrumento e B - sistema SAF®, com prévio alargamento manual até o instrumento K #20, aplicação da SAF® por 4 minutos, com fluxo de irrigação pelo sistema VATEA de 5mL/min. Os dentes foram divididos em três subgrupos conforme a irrigação final: G1-NaOCl 1%, G2- EDTA 15% e G3 Quitosana 0,20%. Utilizou-se 5mL de cada solução à 1mL/min. A solução extravasada pelo forame foi coletada e submetida à análise espectrométrica. O EDTA 15% apresentou maior capacidade de remoção de íons cálcio do que a Quitosana a 0,20% (p<0,05) e o NaOCl 1% não removeu íons. Os espécimes foram analisados em MEV. As fotomicrografias obtidas foram avaliadas qualitativamente em relação à remoção da camada de smear observada. Não houve diferença entre as instrumentações rotatória e SAF® nos terços dos canais avaliados. Analisadas as interações entre as técnicas utilizadas e aos terços do canal, o EDTA 15% apresentou melhores resultados que a Quitosana 0,20% (p<0,05), sendo ambas as soluções melhores que o NaOCl 1%. Conclui-se que as soluções quelantes testadas foram capazes de remover íons cálcio das paredes dos canais radiculares - com superioridade do EDTA 15% sobre a Quitosana 0,20%, e o NaOCl a 1% não apresentou essa capacidade - e removeram a camada de smear das paredes dos canais radiculares com superioridade do EDTA 15%, sem interferência das técnicas de instrumentação avaliadas rotatória e SAF®. / The present study evaluated, by scanning electron microscopy (SEM), the cleanness of the root canal walls instrumented by rotary and the self-adjusting file (SAF®) techniques using 1% NaOCl as an irrigating solution and 15% EDTA, 0.20% Chitosan as chelator solutions, and quantified the calcium ions removed by the different irrigants with atomic absorption spectrometry. Thirty human mandibular canine teeth were divided into 2 groups (n=15) according to the instrumentation technique used: A- FlexMaster® instruments used with the Free tip Preparation, assuring a minimal enlargement of 200m, up to a #60 .02 instrument, irrigated with 1mL of 1% NaOCl between each instrument; and B- SAF® system, with previous enlargement to a type K #20 manual instrument, application of SAF during 4 minutes, with VATEA irrigation system at a flow of 5mL/min. The teeth were divided into three subgroups according to the final irrigation protocol: G1- 1% NaOCl, G2- 15% EDTA and G3- 0.20 % Chitosan. Five mL of solution were used at 1mL/min. The solution extruded thru the foramen was collected and submitted to spectrometric analysis. 15% EDTA showed higher calcium ion removal capacity then 0.20% Chitosan (p<0.05) and the 1% NaOCl did not remove ions. The specimens were evaluated by means of SEM. The photomicrographs obtained were qualitatively evaluated in terms of smear layer removal. There was no significant difference between the rotary and SAF® instrumentation systems in the evaluated canal thirds. The interaction techniques used and canals thirds showed that the 15% EDTA revealed better results than the 0.02% Chitosan (p<0.05), and both were better than 1% NaOCl. It can be concluded that the tested chelating solutions removed calcium ions from the root canals walls with better results for 15% EDTA than 0.20% Chitosan; 1% NaOCl did not present this capacity - and removed the smear layer form the root canal walls with better results for 15% EDTA, with no difference between the evaluated techniques rotary and SAF®.

Diese Arbeit betrachtet die Wechselwirkung von solarer Einstrahlung mit Wolken in der Atmosphäre. Diese wird insbesondere repräsentiert durch den Wolkenstrahlungseffekt. Hierbei wurde vor allem auf die Auswirkungen von kleinskaliger Variabilität von Wolken und Wolkenfeldern auf die Genauigkeit des Wolkenstrahlungseffektes am Oberrand der Atmosphäre und am Boden Rücksicht genommen. Mit einer Schliessungsstudie ist der modellierte Wolkenstrahlungseffekt mit Schiffsmessungen verglichen worden. Hierbei wurden die Wolkeneigenschaften in dem Modell durch Schiffs- und Satellitendaten als Eingangsdatensatz beschrieben. Ein Zugewinn in der Genauigkeit konnte durch die kombinierte Nutzung beider Datenquellen erzielt werden, konkret durch die Kombination des Flüssigwasserpfads aus Schiffsmessungen und des effektiven Radius aus Satellitenbeobachtungen. Durch die Schliessungsstudie sind zwei Probleme in der Auflösung kleinskaliger Bewölkung und deren Auswirkung auf abgeleitete Wolkeneigenschaften identifiziert worden, die im weiteren Verlauf der Arbeit genauer betrachtet wurden. Ein Vergleich zweier Methoden zur Erkennung des Bedeckungsgrades, jeweils eine vom Boden und eine vom Oberrand der Atmosphäre, hat insgesamt eine gute Übereinstimmung ergeben. Jedoch zeigten sich Abweichungen bei geringer Bedeckung. So wurde bei einem Bedeckungsgrad von ca. 40% in der Hälfte der Fälle den Satellitenbildpunkt als bewölkt klassifiziert. Diese Unsicherheiten in der Klassifikation konnten auf die abgeleitete reflektierte solare Einstrahlung übertragen werden. Für als unbewölkt erkannte, tatsächlich aber bewölkte, Bildpunkte wurde eine mittlere Überschätzung der reflektierte solare Einstrahlung von ca. 30 W/m−2 gefunden. Ebenfalls wurde der Einfluss der zeitlichen Variabilität in der solaren Einstrahlung auf die Bestimmung des Wolkenstrahlungseffektes einer Wolke untersucht. Hierfür wurde ein lineares Modell entwickelt und präsentiert, das die diffuse Einstrahlung mit dem Bedeckungsgrad in Zusammenhang stellt. Das Modell liefert zwei Koeffizienten, die die Variation der diffusen Einstrahlung durch eine Wolke unter der Annahme, dass die beobachtete Wolke den ganzen Himmel bedeckt, beschreiben. Dies ermöglicht einen direkten Vergleich des Wolkenstrahlungseffektes einer beobachteten Wolke mit Modellergebnissen und die Entkopplung von der zeitlich variablen direkten Einstrahlung.

Diese Arbeit betrachtet die Wechselwirkung von solarer Einstrahlung mit Wolken in der Atmosphäre. Diese wird insbesondere repräsentiert durch den Wolkenstrahlungseffekt. Hierbei wurde vor allem auf die Auswirkungen von kleinskaliger Variabilität von Wolken und Wolkenfeldern auf die Genauigkeit des Wolkenstrahlungseffektes am Oberrand der Atmosphäre und am Boden Rücksicht genommen. Mit einer Schliessungsstudie ist der modellierte Wolkenstrahlungseffekt mit Schiffsmessungen verglichen worden. Hierbei wurden die Wolkeneigenschaften in dem Modell durch Schiffs- und Satellitendaten als Eingangsdatensatz beschrieben. Ein Zugewinn in der Genauigkeit konnte durch die kombinierte Nutzung beider Datenquellen erzielt werden, konkret durch die Kombination des Flüssigwasserpfads aus Schiffsmessungen und des effektiven Radius aus Satellitenbeobachtungen. Durch die Schliessungsstudie sind zwei Probleme in der Auflösung kleinskaliger Bewölkung und deren Auswirkung auf abgeleitete Wolkeneigenschaften identifiziert worden, die im weiteren Verlauf der Arbeit genauer betrachtet wurden. Ein Vergleich zweier Methoden zur Erkennung des Bedeckungsgrades, jeweils eine vom Boden und eine vom Oberrand der Atmosphäre, hat insgesamt eine gute Übereinstimmung ergeben. Jedoch zeigten sich Abweichungen bei geringer Bedeckung. So wurde bei einem Bedeckungsgrad von ca. 40% in der Hälfte der Fälle den Satellitenbildpunkt als bewölkt klassifiziert. Diese Unsicherheiten in der Klassifikation konnten auf die abgeleitete reflektierte solare Einstrahlung übertragen werden. Für als unbewölkt erkannte, tatsächlich aber bewölkte, Bildpunkte wurde eine mittlere Überschätzung der reflektierte solare Einstrahlung von ca. 30 W/m−2 gefunden. Ebenfalls wurde der Einfluss der zeitlichen Variabilität in der solaren Einstrahlung auf die Bestimmung des Wolkenstrahlungseffektes einer Wolke untersucht. Hierfür wurde ein lineares Modell entwickelt und präsentiert, das die diffuse Einstrahlung mit dem Bedeckungsgrad in Zusammenhang stellt. Das Modell liefert zwei Koeffizienten, die die Variation der diffusen Einstrahlung durch eine Wolke unter der Annahme, dass die beobachtete Wolke den ganzen Himmel bedeckt, beschreiben. Dies ermöglicht einen direkten Vergleich des Wolkenstrahlungseffektes einer beobachteten Wolke mit Modellergebnissen und die Entkopplung von der zeitlich variablen direkten Einstrahlung.

The aviation industry stands for about 2% of the global CO2 emissions and constitutes a large portion of what the individual can affect by their own decision making. A direct round-trip Stockholm to New York consumes about 50% of an individual's annual CO2 budget. This paper studies what role carbon offsetting has in the transition towards sustainable aviation. Sustainable aviation fuels (SAFs), electrical aviation and abstaining from flying are also considered as potential approaches to making aviation more sustainable. The research method is both empirical and theoretical. Empirically, a Carbon Offsetting Assessment Framework evaluates airlines’ and online travel agencies’ (OTAs’) work with carbon offsetting and SAF. This is done from a Sweden-centric perspective. The airlines BRA, KLM and SAS score highest. Theoretically, a discussion of the dynamics of the aviation industry’s transition into sustainability is carried out through the multi-level perspective (MLP). Carbon offsetting is considered the best short-term solution for sustainable aviation due to availability and costefficiency. SAF is currently too expensive and the usage too low to yield significant emission reductions but is a promising mid-term solution. In the long-run, electrical aviation is the solution that has the potential to lower direct emissions to almost zero but it relies on major energy storage development and is not commercially viable today. The study also explains why carbon offsetting not should be used as a letter of indulgence but still is a good way to be certain that climate positive actions happen now and not are postponed or not happen at all. / Flygindustrin står för ungefär 2% av de globala CO2-utsläppen och utgör en stor andel av vad individen kan påverka genom sitt eget beslutsfattande. En direktresa tur- och retur Stockholm till New York konsumerar ungefär 50% av en individs ärliga CO2-budget. Den här studien undersöker vilken roll klimatkompensation har i en övergång mot hållbart flyg. Hållbart flygbränsle (SAF), elflyg och att avstå från att flyga har också utvärderats som potentiella tillvägagångssätt för att göra flyget mer hållbart. Studiens forskningsmetod är både empirisk och teoretisk. En modell för att empiriskt utvärdera flygbolags och onlineresebyråers (OTAs) arbete med klimatkompensation och SAF appliceras på en Sverigecentriskt urval av aktörer. Flygbolagen BRA, KLM och SAS får högst poäng. Vidare förs en teoretisk diskussion om dynamiken i flygbranschens övergång mot hållbart flyg genom “the multi-level perspective” (MLP). Klimatkompensation anses vara den bästa kortsiktiga lösningen för hållbart flyg eftersom det är tillgängligt och kostnadseffektivt. SAF är idag för dyrt och användandet för lågt för att resultera i betydelsefulla utsläppsminskningar men är icke desto mindre en lovande teknik på medellång sikt. På lång sikt är elflyg lösningen som har potential att minska direktutsläpp till nästan noll men det står och faller med avsevärd teknikutveckling inom energilagring och är inte kommersiellt tillgängligt idag. Studien förklarar också varför klimatkompensation inte borde användas som ett avlatsbrev men att det fortfarande är ett bra sätt att försäkra sig om att klimatpositiva handlingar sker idag och inte blir uppskjutna eller uteblir.

This thesis report presents a method to analyze the communication architecture for the Intelligent Transportation Systems (ITS). The report also includes a case study on ASN.1 notation and analysis of its encoding rules. Included in the report is also: (i) accompanying instruction on how to use ASN.1 compilers to produce the C/C++ message encoder/decoder, and (ii) analysis of Non-IP communications of Communication Access for Land Mobiles (CALM-FAST) protocol stack in ITS. The thesis is a part of the research project entitled “SCOOP”, a joint project between SCANIA CV AB and KTH. The purpose of this thesis is to contribute to the ultimate goal, which is to equip a vehicle with necessary hardware and software technology to provide a platooning behavior in the GCDC 2011 competition. This goal is achieved by the means of wireless communication system for both vehicle to vehicle and vehicle to road side units communications in the platoon. Overall, this thesis introduces the important usage of ASN.1 in implementation of cut-edge telecommunication systems especially in V2V and V2I communication; and clarifies the CALM-FAST protocol stack in mobile nodes. / Kartlägga CALM-FAST protokollet och hur det användes tillsammans med den i tävlingen GCDC 2011 fastslanga kommunikationsprotokollet. GCDC var ett tävling i kooperativ körning arrangerad och initierad av Hollänska TNO och gick ut på att få fordon att agera tillsammans beserat på information sänt via WLAN 802.11p. ASN.1 användes och ingick i analysen.

This work presents a detailed investigation of magnetization dynamics in synthetic antiferromagnets (SAFs), which has been studied both experimentally, using electrically-detected ferromagnetic resonance (ED-FMR) and vector-network analyzer-based ferromagnetic resonance (VNA-FMR), and theoretically. Two modes, one with in-phase and one with 180° out-of-phase precessing magnetizations of the layers, are identified in all applied field regimes, namely, a low-field antiferromagnetically coupled regime (when magnetizations of the layers have opposite directions), a spin-flop regime at intermediate field values (when magnetizations are non-collinear) and a high-field saturation regime (when both magnetazations are collinear to each other and the external magnetic field direction). The qualitative theoretical description, found to be in good agreement with the experimental data, is given using a system of coupled Landau-Lifshitz equations. In this work, for the first time to our knowledge, it is shown that for SAFs with different magnetic moments of the individual layers, dynamic, and not static, Zeeman and interlayer exchange coupling energies are solely resposible for the frequency-field dependence in the antiferromagnetically coupled regime. The changes in the dynamical energy terms lead to the changes in the dynamical components of the precessing magnetizations. As the external magnetic field is varied, the amplitude of the components vary continiously in different ways for different modes, dropping to zero in the spin-flop regime, which is reflected in the amplitudes of ED-FMR and VNA-FMR. This effect appears only in SAFs with different magnetic moments of the layers and is related to the different increase in the Zeeman energy of the layers as the externally applied field increases. The variation of the dynamical components leads to the modulation of an exchange of spin-angular momentum between the layers (so called spin-pumping effect).This is directly reflected in the measured linewidths for the modes in both ED-FMR and VNA-FMR. As was shown before in the literature and is also confirmed here, spin-pumping leads to a constant difference in linewidths between two modes for SAFs in the saturated case. Here, we extend the previous findings to non-saturated regimes. We show that in non-saturated states, the linewidth difference does not remain constant and varries with the external magnetic field. This linewidth difference changes can be qualitatively explained using the modulation of the dynamical magnetization components. In order to directly model the spin-pumping effects, additional terms are introduced in the coupled Landau-Lifshitz equations, related to the intrinsic damping in the magnetic layers and spin-pumping induced effects. The calculations of linewidth dependences using the extended model are not in full agreement with the experiments, suggesting that additional effects must be added to the model (for example, potential domain formations). Additionly, due to the dependence of the effect on the Zeeman energy asymmetry between the layers of the SAF, SAFs with different ratio of thicknesses are studied. Although the trends described above are common to all the samples, no significant enhancement of spin-pumping effects are observed. Modeling shows that, although the evolution of the dynamical magnetization components does depend on the magnetic moment ratio between the layers, the difference between maximum and minimum values remains almost constant and does not alter the observed linewidth-field dependence.:1 Fundamentals 1 1.1 Magnetic moment 1 1.2 Magnetic energy contributions 6 1.2.1 Zeeman energy 6 1.2.2 Demagnetization energy 7 1.2.3 Magnetic anisotropy 9 1.2.4 Direct Exchange Energy 13 1.2.5 Indirect Exchange. Interlayer Exchange Coupling Energy 15 1.3 Magnetoresistance 17 1.3.1 Ordinary Magnetoresistance 17 1.3.2 Anisotropic Magnetoresistance 20 1.3.3 Giant Magnetoresistance 22 1.4 Magnetization dynamics 25 1.4.1 Classical motivation 25 1.4.2 Quantum mechanical justification 27 1.5 Spin-currents and Spin-pumping 29 2 Experimental methods 33 2.1 Vibrating Sample Magnetometry 33 2.2 Ferromagnetic resonance 34 2.2.1 Cavity-FMR 35 2.2.2 VNA-FMR 36 2.3 Electrically detected ferromagnetic resonance 39 3 Synthetic antiferromagnets. Theoretical model 47 3.1 Static model 47 3.2 Dynamical model 54 4 Sample fabrication and characterization 58 4.1 Fabrication 58 4.2 Static characterization 62 5 Magnetization dynamics in asymmetric SAFs 68 5.1 Dynamical measurements on Py(3nm)/ Ru(0.85 nm)/Py(9 nm) 68 5.2 Theoretical explanation 71 5.3 Dynamics in SAFs with varying asymmetry of the layers 80 6 High-frequency spin-pumping in SAFs 86 6.1 Spin-pumping in magnetic trilayers 86 6.2 Spin-pumping in SAFs 88 6.3 Dependence on the asymmetry between the layers 94 7 Conclusions and outlook 99 A General description of the trilayer system without damping and spin-pumping contributions 102 A.1 Effective fields 103 A.2 Final equations 107 B Mathematica program used for the theoretical modeling 108 B.1 Matrix Elements 108 B.2 Frequency-Modes 109 B.3 Dynamical components and corresponding dynamical energies 112 B.4 Equilibrium condition 114 B.5 Dynamical Energies 118 B.6 Dynamical Trajectories 121 Bibliography 125

Cloudiness and solar radiation affect the Earth's energy and water cycle and spa- tial distribution of these parameters is also connected to the atmospheric pressure field and atmospheric circulation. This thesis starts with a short overview of remote sensing of the atmosphere, the EUMETSAT organisation and its section CM SAF which focuses on the uses of satellite data for climate monitoring. Next is a description of cloud and ra- diation products used in this thesis. Daily means of these products in the Czech Republic are then used to calculate mean values, trends and anomalies for the whole time series. Obtained values are compared based on the weather circulation type using the Brádka classification. 1

In large scale entity-level military force-on-force simulations it is essential to know when one entity can visibly see another entity. This visibility determination plays an important role in the simulation and can affect the outcome of the simulation. When virtual Computer Generated Forces (CGF) are introduced into the simulation these intervisibilities must now be calculated by the virtual entities on the battlefield. But as the simulation size increases so does the complexity of calculating visibility between entities. This thesis presents an algorithm for performing these visibility calculations using Graphical Processing Units (GPU) instead of the Central Processing Units (CPU) that have been traditionally used in CGF simulations. This algorithm can be distributed across multiple GPUs in a cluster and its scalability exceeds that of CGF-based algorithms. The poor correlations of the two visibility algorithms are demonstrated showing that the GPU algorithm provides a necessary condition for a "Fair Fight" when paired with visual simulations.

Abstract When producing ferrochrome, a submerged arc furnace (SAF) is used. The charge of an SAF consists of chromite pellets, coke, lumpy ore and quartzite as a slag modifier. The charge is pre-heated before it descends into the SAF where the charge eventually reduces and melts. The electrical conductivity of the charge is important because, among other things, it affects the productivity of the furnace. The electrical conductivity of the charge should ideally be low on the higher parts of the furnace and high near the electrode tip. This is to ensure that the electric current path travels through the metal bath via arcing, which provides the most effective heat transfer. Another option for the current path would be through the solid feed material via ohmic conduction, but since this zone is less reactive, the heat energy would be mostly wasted. This work brings forth new information about the electrical behaviour of coke and chromite pellet is produced. The electrical conductivity was measured at room temperature for different simulated process conditions (different coke textures, different reduction degrees of chromite pellets, sulphur in atmosphere and replacing the coke used in chromite pellet production with charcoal). It was found out that unlike gasification with a CO/CO2 mixture, heat treatment at 950&#176;C increased the degree of graphitization and changed the electrical behaviour of coke. Furthermore, it was observed that increasing the chromite pellets’ reduction degree reduced the electrical conductivity measured at room temperature. In the case of chromite pellets and sulphur in the atmosphere it was found that sulphur has an effect on the pellets’ electrical behavior and structure during reduction, which - in turn - has an effect on the SAF performance when raw materials with varying sulphur contents are used. Lastly, it was found that substituting coke with charcoal when producing chromite pellets affects the sintering behaviour, cold compression strength, and electrical conductivity of the chromite pellets. / Tiivistelmä Uppokaariuuni on osa ferrokromin valmistusprosessia. Uppokaariuuniin panostetaan kromiittipellejä, koksia, palarikastetta ja kvartsiittia. Etukuumennusuunista panos laskeutuu uppokaariuuniin, jossa se pelkistyy ja lopulta sulaa. Uppokaariuunin panoksen sähkönjohtavuus on tärkeää uunin toiminnan kannalta, koska se vaikuttaa suoraan esimerkiksi tuottavuuteen. Jotta virran kulku tapahtuisi optimaalisesti sulan metallin kautta, panoksen sähkönjohtavuuden tulee olla pieni uunin yläosissa ja suuri alaosassa lähellä elektrodien päitä. Mikäli virran kulku tapahtuu uunin yläosassa, hukataan lämpöenergiaa ja uunin toiminta hankaloituu. Tässä työssä on selvitetty koksin ja kromiittipellettien sähköisiä ominaisuuksia. Sähkönjohtavuutta on tutkittu useilla simuloiduilla prosessiolosuhteilla (koksin eri tekstuurit, kromiittipellettien eri pelkistysasteet, rikin pitoisuus atmosfäärissä ja kromiittipellettien valmistuksessa on korvattu koksi puuhiilellä). Nämä mittaukset on tehty huonelämpötilassa. Huomattiin, että toisin kuin koksin kaasutus, koksin lämpökäsittely (950&#176;C) nosti grafitoitumisastetta ja vaikutti sähköisiin ominaisuuksiin. Kromiittipelletin pelkistymisasteen noustessa huonelämpötilassa mitattu sähkönjohtavuus laski. Kun kromiittipelletit altistetaan atmosfäärille, jossa on rikkiä, pellettien sähköiset ominaisuudet muuttuvat samoin kuin rakenne pelkistyksen aikana. Tämä vaikuttaa uppokaariuunin toimintaan, kun käytetään raaka-aineita, joissa rikkipitoisuus vaihtelee. Kun kromiittipellettien valmistuksessa käytettävä koksi korvataan puuhiilellä, tämä vaikuttaa sintrausprosessiin, kylmälujuuteen ja sähköisiin ominaisuuksiin.