Made available in DSpace on 2016-04-04T18:27:38Z (GMT). No. of bitstreams: 1 Marcelo Gulini Chiodi.pdf: 363388 bytes, checksum: 0578a0c625e8841b1da092c135b88eb8 (MD5) Previous issue date: 2007-12-14 / Pontif?cia Universidade Cat?lica de Campinas / The study of intellectual evaluation has shown great diversity through out the time. Currently, the theory recognized as the most extensive to explain the mental functioning is the C-H-C (Cattell-Horn-Carroll). Among the tests internationally availables, the only one that meets this proposal is the theoretical battery Woodcock Johnson III (WJ - IIII). Accordingly, the objective of this study was to verify the convergence validity battery of Cognitives Abilities Woodcock-Johnson III, comparing it with the Wechsler Intelligence Scale for Children - WISC-III, already validated for our reality. The sample was composed of 30 students from public school of Primary and Secondary Education, being 15 men and 15 women aged between 13 and 15 years. It was applied to the participants, with parents permission, the two sets of Cognitive Abilities WJ-III and WISC-III. The results were analyzed according to the Pearson correlation and it was performed the Analysis of Variance between gender and age for each instrument. The results pointed to a significant correlation between the total score of Woodcock and the total score in the WISC of 0,865, between Woodcock and the scale implementation 0,766 and the scale verbal 0,843. As for the Analysis of Variance, in the instrument WISC-III there was no significant difference in age and in subtestes Complete Figures and Cubes Sex x Age to the subtest vocabulary. In addition, for the instrument WJ-III there were differences of Sex X Age only for subtest Verbal Understanding. The Battery Woodcock Johnson III is considered the most complete in order to allow the evaluation of different differents cognitive abilities of the model C-HC, and therefore, according to the presents results, the battery WJ-III can be used in Brazil to replace the WISC - III. / O estudo da avalia??o intelectual tem apresentado grande diversidade atrav?s dos tempos. Atualmente, a teoria reconhecida como sendo a mais ampla para explicar o funcionamento mental ? a C-H-C (Cattell-Horn-Carroll) . Dentre os testes dispon?veis internacionalmente, o ?nico que atende a esta proposta te?rica ? a Bateria Woodcock-Johnson III (WJ-IIII). Neste sentido, o objetivo deste trabalho foi verificar a validade convergente da Bateria de Habilidades Cognitivas Woodcock Johnson-III, comparando-a com a Escala Wechsler de Intelig?ncia para Crian?as WISC- III, que j? apresenta evidencias de validada para a nossa realidade. A amostra foi composta por 30 estudantes de escola p?blica do Ensino Fundamental e M?dio, sendo 15 homens e 15 mulheres com idades entre 13 e 15 anos. Foram aplicadas nos participantes, com a autoriza??o dos pais, as duas baterias de Habilidades Cognitivas WJ-III e WISC-III. Os resultados obtidos foram analisadas segundo a correla??o de Pearson e foi realizada a An?lise de Vari?ncia entre sexo e idade para cada instrumento. Os resultados apontaram para uma correla??o significativa entre a pontua??o total do Woodcock e a pontua??o total no WISC de 0,865, entre o Woodcock e a escala execu??o 0,766 e com a escala verbal 0,843. Com rela??o a An?lise de Vari?ncia, no instrumento WISC-III houve diferen?a significativa da Idade nos subtestes Completar Figuras e Cubos e de Sexo X Idade para o subteste Vocabul?rio. J? com o instrumento WJ-III houve diferen?as de Sexo X Idade somente para o subteste Compreens?o Verbal. Tais dados nos indicam que a Bateria de Habilidades Cognitivas Woodcock-Johnson- III- WJ-III permite uma avalia??o e um diagn?stico mais detalhado das v?rias habilidades cognitivas, podendo enriquecer ainda mais as possibilidades de instrumentos para avalia??o intelectual.

This thesis focuses on the politics of Antipope Victor IV and his successors Paschal III, Calixtus III and Innocent III, who were the opponents of Alexander III since the schismatic elections of 1159. The aim is to analyse the political thinking and actions of the antipopes, with an emphasis on the political relations of Victor IV. The thesis is divided into six thematic sections. The first deals with the pre-election developments and the election of 1159 itself. The second considers their position in relation to Alexander III, while the third turns to the papal-imperial policy and examines the relationship between the antipopes and Emperor Frederick Barbarossa. The fourth section discusses the status and relations of the antipopes outside the Holy Roman Empire. The penultimate chapter examines the attitude of the imperial clergy to the pontificates of the antipopes as well as the obedience of the imperial monasteries, according to papal documents. The final chapter constructs biographies of the antipopes, focusing on the period before their pontificates.

High-valent iron-oxo intermediates play central roles as active oxidants in enzymatic and synthetic catalytic oxidations. Many transition metal catalysts are designed for biomimetic studies of the predominant oxidation catalysts in Nature, the cytochrome P450 enzymes. In this work, a new photochemical method to generate high-valent iron-oxo porphyrin models was discovered. As controlled by the electronic nature of porphyrin ligands, iron(IV)-oxo porphyrin radical cations (Compound I model) and iron(IV)-oxo porphyrin derivatives (Compound II model) were produced. These observations indicate that the photochemical reactions involve a heterolytic cleavage of O-Br in precursors to give a putative iron(V)-oxo intermediate, which might relax to Compound I through electron transfer from porphyrin to the iron or undergo rapid comproportionation reaction with residual iron(III) to afford the Compound II derivative. Furthermore, visible light photolysis of bis-porphyrins-dimanganese(III)-μ-oxo complexes, [MnIII(Por)]2O, was studied in three porphyrin systems. Direct conversion of manganese(III)-μ-oxo dimers to manganese(IV)-oxo porphyrins [MnIV(Por)(O)] and manganese(III) products was observed in benzene solution upon light irradiation. The spectral signature of [MnIV(Por)(O)] was further confirmed by production of the same species in the reported reaction of the [MnIII(Por)Cl] with PhI(OAc)2. Continuous irradiation of bis-porphyrins-dimanganese(III)-μ-oxo complexes in the presence of pyridine or triphenylphospine gave rise to the formation of [MnII(Por)(Py)] or [MnII(Por)(PPh3)], which are stable to be detected. A photo-disproportionation mechanism similar to that for bis-porphyrins-diiron(III)-μ-oxo complex was proposed to explain above photochemical behaviors of bis-porphyrins-dimanganese(III)-μ-oxo complexes. With iodobenzene diacetate [PhI(OAc)2] as the oxygen source, manganese(III) porphyrin complexes exhibit remarkable catalytic activity towards the selective oxidation of alkenes and activated hydrocarbons. Conspicuous is the fact that the readily soluble PhI(OAc)2 in the presence of a small amount of water is more efficient oxygen source than the commonly used PhIO under same conditions. High selectivity for epoxides and excellent catalytic efficiency with up to 10,000 Turnovers (TONs) were achieved in alkene epoxidations. A manganese(IV)-oxo porphyrin was observed in the oxidation of the manganese(III) porphyrin and PhI(OAc)2. However, catalytic competition and Hammett studies suggested that the more reactive manganese(V)-oxo intermediate was favored as the premier active oxidant, even it is too short-lived to be detected in the catalytic reaction.

Les MOSFETs ultra-thin body UTB ont été fabriqués avec une technologie auto-alignée. Le canal conducteur est constitué d’InGaAs à 75% de taux d’indium ou d’un composite InAs/In0,53Ga0,47As. Une fine couche d'InP (3 nm) a été insérée entre le canal et l'oxyde, afin d’éloigner les défauts de l’interface oxyde-semiconducteur du canal. Enfin, une épaisseur de 4 nm d'oxyde de grille (Al2O3) a été déposée par la technique de dépôt des couches atomiques. Les contacts ohmiques impactent les performances des MOSFETs. La technologie UTB permet difficilement d’obtenir des contacts S/D de faibles résistances. De plus, l’utilisation de la technique d’implantation ionique pour les architectures UTB est incompatible avec le faible budget thermique des matériaux III-V et ne permet pas d’obtenir des contacts ohmiques de bonne qualité. Par conséquent, nous avons développé une technologie auto-alignée, basée sur la diffusion du Nickel « silicide-like » par capillarité à basse température de recuit (250°C) pour la définition des contacts de S/D. Finalement, nous avons étudié et analysé la résistance de l'alliage entre le Nickel et les III-V. A partir de cette technologie, des MOSFET In0,75Ga0,25As et InAs/In0,53Ga0,47As ont été fabriqués. On constate peu de différences sur les performances électriques de ces deux composants. Pour le MOSFET InAs/InGaAs ayant une longueur de grille LG =150 nm, un courant maximal de drain ID=730 mA/mm, et une transconductance extrinsèque maximale GM, MAX = 500 mS/mm ont été obtenu. Le dispositif fabriqué présente une fréquence de coupure fT égale à 100 GHz, et une fréquence d'oscillation maximale fmax de 60 GHz, pour la tension drain-source de 0,7 V. / Abstract : Silicon-based devices dominate the semiconductor industry because of the low cost of this material, its technology availability and maturity. However, silicon has physical limitations, in terms of mobility and saturation velocity of the carriers, which limit its use in the high frequency applications and low supply voltage i.e. power consumption, in CMOS technology. Therefore, III-V materials like InGaAs and InAs are good candidates because of the excellent electron mobility of bulk materials (from 5000 to 40.000 cm2 /V.s) and the high electron saturation velocity. We have fabricated ultra-thin body (UTB) InAs/InGaAs MOSFET with gate length of 150 nm. The frequency response and ON-current of the presented MOSFETs is measured and found to have comparable performances to the existing state of the art MOSFETs as reported by the other research groups. The UTB MOSFETs were fabricated by self-aligned method. Two thin body conduction channels were explored, In0,75Ga0,25As and a composite InAs/In0,53Ga0,47As. A thin upper barrier layer consisting of InP (3nm) is inserted between the channel and the oxide layers to realized a buried channel. Finally, the Al2O3 (4 nm) was deposited by the atomic layer deposition (ALD) technique. It is well known that the source and drain (S/D) contact resistances of InAs MOSFETs influence the devices performances. Therefore, in our ultra-thin body (UTB) InAs MOSFETs design, we have engineered the contacts to achieve good ohmic contact resistances. Indeed, for this UTB architecture the use of ion implantation technique is incompatible with a low thermal budget and cannot allow to obtain low resistive contacts. To overcome this limitation, an adapted technological approach to define ohmic contacts is presented. To that end, we chose low thermal budget (250°C) silicide-like technology based on Nickel metal. Finally, we have studied and analyzed the resistance of the alloy between Nickel and III-V (Rsheet). MOSFET with two different epilayer structures (In0,75Ga0,25As and a composite InAs/In0,53Ga0,47As) were fabricated with a gate length (LG) of 150 nm. There were few difference of electrical performance of these two devices. We obtained a maximum drain current (ION) of 730 mA/mm, and the extrinsic transconductance (GM, MAX) showed a peak value of 500 mS/mm. The devices exhibited a current gain cutoff frequency fT of 100 GHz and maximum oscillation frequency fmax of 60 GHz for drain to source voltage (VDS) of 0.7 V.

In this study the performance of pure, very fine iron (III) oxide powder was investigated as catalyst for the decomposition of sulphur trioxide into sulphur dioxide and oxygen. This highly endothermic reaction requires a catalyst to lower the reaction temperature. This reaction forms part of the HyS (Hybrid Sulphur) cycle, a proposed thermochemical process for the industrial scale production of hydrogen and oxygen from water. The study aimed at obtaining reaction kinetics for this reaction employing pure, unsupported iron (III) oxide as catalyst as a cheaper alternative compared to supported iron catalysts. It was found that the SO3 conversion was carried out in the absence of diffusion limitations and that the reverse reaction did not play a significant role. By assuming plug flow conditions in the reactor and 1st order kinetics, the kinetic parameters of the reaction were obtained. These parameters that form part of the Arrhenius law in describing the reaction rate constant, were determined to be 118(±23) kj / mol for the activation energy ( Ea ), and a value of 3(±0.5) x 108hr-1 was obtained for the Arrhenius frequency factor ( A ). Both values correspond to literature, although in general larger activation energies were published for iron (III) oxide derived supported catalysts. A comparison of the performance of the pure, unsupported iron (III) oxide catalyst with other iron (III) oxide derived supported catalysts (or pellets) has shown that the pure iron (III) oxide catalyst exhibit similar activities. Avoiding expensive catalyst preparation will be an initial step in the direction of developing a cost effective catalyst for the decomposition of sulphur trioxide. It is, however, recommended to investigate different particle sizes as well as purity levels of the unsupported iron (III) oxide to find an optimum cost to performance ratio, as the degree of fineness and the degree of purity will largely influence the final catalyst cost. A qualitative investigation with various reaction product species as well as water in the reactor feed was conducted to assess the influence of these species on the reaction rate. The addition of these species seems to have a larger influence on the reaction rate at low reaction temperatures around 700°C than at higher reaction temperatures (i.e. 750°C and 825°C). This can be attributed to adsorption rates of such species that reduce at higher temperatures. Observations at higher reaction temperatures also suggest that the reaction is of a first-order nature. / MIng (Chemical Engineering), North-West University, Potchefstroom Campus, 2014

In this study the performance of pure, very fine iron (III) oxide powder was investigated as catalyst for the decomposition of sulphur trioxide into sulphur dioxide and oxygen. This highly endothermic reaction requires a catalyst to lower the reaction temperature. This reaction forms part of the HyS (Hybrid Sulphur) cycle, a proposed thermochemical process for the industrial scale production of hydrogen and oxygen from water. The study aimed at obtaining reaction kinetics for this reaction employing pure, unsupported iron (III) oxide as catalyst as a cheaper alternative compared to supported iron catalysts. It was found that the SO3 conversion was carried out in the absence of diffusion limitations and that the reverse reaction did not play a significant role. By assuming plug flow conditions in the reactor and 1st order kinetics, the kinetic parameters of the reaction were obtained. These parameters that form part of the Arrhenius law in describing the reaction rate constant, were determined to be 118(±23) kj / mol for the activation energy ( Ea ), and a value of 3(±0.5) x 108hr-1 was obtained for the Arrhenius frequency factor ( A ). Both values correspond to literature, although in general larger activation energies were published for iron (III) oxide derived supported catalysts. A comparison of the performance of the pure, unsupported iron (III) oxide catalyst with other iron (III) oxide derived supported catalysts (or pellets) has shown that the pure iron (III) oxide catalyst exhibit similar activities. Avoiding expensive catalyst preparation will be an initial step in the direction of developing a cost effective catalyst for the decomposition of sulphur trioxide. It is, however, recommended to investigate different particle sizes as well as purity levels of the unsupported iron (III) oxide to find an optimum cost to performance ratio, as the degree of fineness and the degree of purity will largely influence the final catalyst cost. A qualitative investigation with various reaction product species as well as water in the reactor feed was conducted to assess the influence of these species on the reaction rate. The addition of these species seems to have a larger influence on the reaction rate at low reaction temperatures around 700°C than at higher reaction temperatures (i.e. 750°C and 825°C). This can be attributed to adsorption rates of such species that reduce at higher temperatures. Observations at higher reaction temperatures also suggest that the reaction is of a first-order nature. / MIng (Chemical Engineering), North-West University, Potchefstroom Campus, 2014

The Millon Clinical Multiaxial Inventory-Third Edition (MCMI-III) currently ranks among the most commonly utilized personality tools. A review of the literature revealed that ethnic minorities tend to score higher on certain scales of the MMPI and MCMI compared to their White counterparts. The literature also indicated that acculturation level can serve as a moderator variable on overall performance on these measures. Most of the studies that examined racial/ethnic differences on the MCMI were conducted using the MCMI-I and MCMI-II. While many MCMI studies have explored racial differences, few studies have examined the impact of cultural factors on MCMI-III performance. To date, there is no empirical data on the impact of culture on the MCMI-III scores of Blacks from different cultural backgrounds. Given the significant increase in the number of Black immigrants to the United States especially from the Caribbean and Africa, Black Americans are becoming an even more diverse group, representing different cultures and nationalities. In the current study, the performance of African Americans (n = 52) and Caribbean Blacks (n = 77) were compared on the Antisocial, Narcissistic, Paranoid, and Delusional Disorder scales of the MCMI-III. Attempts were also made to compare Blacks in the current sample to the MCMI-III's development sample. Additionally, the impact of cultural variables was examined using the African American Acculturation Scaled-Revised (AAAS-R). Multivariate Analysis of Variance procedure revealed no significant difference in performance between the two groups on the select scales of the MCMI-III (p =.883). Additional analyses revealed significant difference between the two groups on the Compulsive scale: Caribbean Blacks obtained a higher mean (Cohen's d =.-50. F= 6.663, p = .011). Analyses comparing the Blacks in the current sample to the MCMI-III's development sample indicated the following: a) a significant difference between the two groups on the Antisocial, Narcissistic, and Delusional Disorder Scales and b) no significant difference between the two groups on the Paranoid scale (p = .559). Supplemental analysis revealed moderate association between the Paranoid and Delusional Disorder Scales of the MCMI-III and certain scales of the AAAS-R, implying both a degree of item overlap and similar item content.

Manuel M. Ponce skrev Sonata III 1927. Ponce var startkt influerad av kompositörer som Ravel och Debussy och i Sonata III:s första sats märks detta väl. Den är komponerad i en stil som liknar Ravels och Debussys impressionism, full med dramatiska harmonier, överlagringar och polytonalitet, med stora ackord följt av flytande arpeggion och sångbara melodier. Allt skrivet av en man som själv inte kunde spela gitarr, men förstod instrumentet väl. I detta arbete går jag igenom Sonata III:s första sats, genom en analys av formen och verket samt genom att gå igenom hur jag valt att tolka den och varför jag gjort dessa val. / <p>Konsertrepertoar:</p><p>Manuel M. Ponce - Sonata III</p><p>Dionisio Aguado - Andante et Rondo Nr 2, Opus 2</p><p>Benjamin Britten - Nocturnal after John Dowland for guitar, Opus 70</p><p>Medverkande: Pontus Ahlbäck, gitarr.</p><p></p>

International Telemetering Conference Proceedings / October 26-29, 1998 / Town & Country Resort Hotel and Convention Center, San Diego, California / FAA is currently evaluating DGPS based CAT III Landing Systems for use as the next generation commercial aviation landing system standard. Any technique to validate such a DGPS based system must have at least equivalent accuracy. A laser position tracking system coupled with a high performance real-time computational capability was developed providing real-time analysis of performance. This real-time performance measurement system was key in enabling the quick completion of a large number of test approach and landings needed to achieve statistically accurate results.

Thesis (PhD)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: Recent developments in the atmospheric treatment of low-grade nickel laterite ores at Anglo American plc has culminated in the conceptual iron-focused laterite (ARFe) process. In addition to the recovery of nickel and cobalt from laterite ore, this process uniquely aims to recover iron as a saleable by-product. The reduction of soluble iron(III) (Fe(III)) by sulfur dioxide gas (SO2) is central to the ARFe concept and represents a complex, multiphase system involving simultaneous gas-liquid mass transfer, thermodynamic speciation and chemical reaction. The chemistry of iron-containing systems is generally poorly understood and accurately predicting their behaviour is challenging, especially under aggressive hydrometallurgical conditions. The primary objective of this work is the development of an engineering model capable of describing the rate and extent of ferric reduction with SO2 under conditions typical of the ARFe process. Thermodynamic considerations provide a rigorous framework for the interpretation of chemical reactions, however little experimental data are openly available for the associated solution species in acidic iron sulfate systems. A key contribution of this work, and critical for the development of the overall model, is the direct measurement of speciation in iron sulfate solutions. Raman and UV-vis spectroscopy were utilised to make direct speciation measurements in the various subsystems of the Fe2(SO4)3-FeSO4-H2SO4-H2O system that were previously unavailable in the open literature. The FeSO+4 and Fe(SO4)– 2 species were explicitly identified and measurements were supported and rationalised by static computational quantum mechanical calculations and ultimately permit the calibration of a robust, ion-interaction solution model with the explicit recognition of the important solution species up to 1.6 mol/kg Fe2(SO4)3, 0.8 mol/kg H2SO4 over 25 – 90 C. Batch and continuous Fe(III) reduction kinetics were measured and the effects of initial Fe2(SO4)3 and H2SO4 concentrations, temperature and in-situ neutralisation quantified. The retardation effect of sulfuric acid was observed to be the most significant factor influencing the initial reaction rate and the achievable extent of reduction at fixed residence time, which varied between about 20 and 80 % after 180 minutes of reaction. A reaction mechanism that is limited by the slow ligand-to-metal electron transfer in the FeIIISO+3 solution species’ decomposition is proposed and spectroscopic measurements and computational quantum mechanical calculations are used to support this mechanism. A kinetic model, comprising a system of differential mass-balance equations, is incorporated into the thermodynamic framework. This reaction model permits the prediction of kinetic profiles over the full range of experimental conditions and can be incorporated into more elaborate simulation models of the ARFe circuit. The specific original contributions of this work are • The direct measurement of aqueous speciation in the Fe2(SO4)3-H2SO4-H2O system by Raman and UV-vis spectroscopy • The development of a modelling framework to characterise speciation, activity coefficients and solubility in the mixed Fe2(SO4)3-FeSO4-H2SO4-H2O system. • The measurement of Fe(III) reduction kinetics using SO2 in concentrated sulfate solutions as a function of initial composition and temperature. • The development of a solution reaction model of Fe(III) reduction with SO2 that accurately predicts the solution speciation and reaction rate with time as a function of composition and temperature. Lastly, the vast complexity of industrial systems will nearly always result in a lack of specific experimental data that are required for the development of phenomenological models. This work emphasises the crucial role that engineering studies hold in the generation of such data to derive maximum practical value for industrial process development and optimisation. / AFRIKAANSE OPSOMMING: Onlangse ontwikkelinge in die atmosferiese behandeling van lae-graad nikkel lateriet erts by Anglo American plc het gelei tot die konseptuele yster gefokus lateriet (ARFe) proses. Bykommend tot die herwinning van nikkel en kobalt uit laterite erts is hierdie proses uniek en daarop gemik om yster te herwin as ’n verkoopbare by-produk. Die vermindering van oplosbare yster(III) (Fe(III)) met swaeldioksied (SO2) is sentraal tot die ARFe konsep en verteenwoordig ’n komplekse, multifase stelsel wat gelyktydige gas-vloeistof massa-oordrag, termodinamiese spesiasie en chemiese reaksie behels. Die oplossingschemie van ysterstelsels word, oor die algemeen, swak verstaan en om hul gedrag akuraat te voorspel is ’n uitdaging, veral onder aggressiewe hidrometallurgiese kondisies. Die primêre doel van hierdie werk is die ontwikkeling van ’n ingenieursmodel wat die tempo en omvang van yster(III) vermindering met SO2 onder tipiese ARFe proses toestande beskryf. Termodinamiese oorwegings stel ’n streng raamwerk voor vir die interpretasie van chemiese reaksies, alhoewel daar egter min eksperimentele data openlik beskikbaar is vir die gepaardgaande oplossing spesies in suur yster(III) sulfaat stelsels. ’n Belangrike bydrae van hierdie werk, en van kritieke belang vir die ontwikkeling van die algehele model, is die direkte meting van spesiasie in yster(III) sulfaat oplossings. Raman en UV-vis spektroskopie is gebruik om direkte spesiasie metings te maak in die verskillende subsisteme van die Fe2(SO4)3-FeSO4-H2SO4-H2O stelsel wat voorheen nie in die oop literatuur beskikbaar was nie. Die FeSO+4 en Fe(SO4)– 2 spesies is ekplisiet geïdentifiseer, terwyl die metings ondersteun en gerasionaliseer is deur statiese kwantummeganiese berekeninge wat uiteindelik die kalibrasie van ’n robuuste, ioon-interaksie model tot gevolg hê wat ook die belangrike oplossingspesies duidelik beklemtoon tot en met 1.6 mol/kg Fe2(SO4)3, 0.8 mol/kg H2SO4 en tussen 25 – 90°C. Enkellading en kontinue yster(III) verminderingskinetika is gemeet en die gevolge van die aanvanklike Fe2(SO4)3 en H2SO4 konsentrasies, temperatuur en in-situ neutralisasie is gekwantifiseer. Die waargeneemde vertragingseffek van swaelsuur is die mees beduidende faktor wat die aanvanklike reaksietempo en die haalbare reaksie omvangsvermindering na ’n vaste residensietyd van 180 minute bepaal, wat wissel tussen ongeveer 20 en 80%. ’n Reaksiemeganisme word voorgestel wat beperk word deur die stadige ligand-totmetaal elektronoordrag in ontbinding van die Fe(III)SO+3 oplossing-spesies en wat verder deur spektroskopiese metings en kwantummeganiese berekenings ondersteun word. A kinetiese model, wat bestaan uit ’n stelsel van gedifferensieerde massa-balans vergelykings, is in die termodinamiese raamwerk geïnkorporeer. Hierdie reaksie-model laat die voorspelling van kinetiese profiele toe oor die volle omvang van die eksperimentele toestande en kan in meer uitgebreide simulasie modelle van die ARFe proces geinkorporeer word. Die spesifieke en oorspronklike bydraes van hierdie werk is • Die direkte meting van die spesiasie in die Fe2(SO4)3-H2SO4-H2O stelsel deur Raman en UV-vis spektroskopie • Die ontwikkeling van ’n modelraamwerk om spesiasie, aktiwiteitskoëffisiënte en oplosbaarheid in die gemengde Fe2(SO4)3-FeSO4-H2SO4-H2O stelsel te karakteriseer. • Die meting van yster(III) vermideringskinetieka deur SO2 in gekonsentreerde sulfate oplossings te gebruik as ’n funksie van die aanvanklike samestelling en temperatuur. • Die ontwikkeling van ’n oplossingsreaksie-model van yster(III) vermindering met SO2 wat die oplossing-spesiasie en reaksietempo met die tyd as ’n funksie van samestelling en temperatuur akkuraat voorspel. Laastens, die oorgrote kompleksiteit van industriële stelsels sal byna altyd lei tot ’n gebrek van spesifieke eksperimentele data wat nodig is vir die ontwikkeling van fenomenologiese modelle. Hierdie werk beklemtoon die belangrike rol wat ingenieursstudies speel in die generasie van data wat sodanig tot maksimum praktiese waarde vir industriële prosesontwikkeling en optimalisering lei.