In order to reduce the discharge of the greenhouse gas CO2, the use of biomass is nowadays promoted as fuel in boilers. Compared to boilers fired with coal and oil the biomass-fired boilers have more complications related to both fouling and corrosion on the heat transfer surfaces. After the combustion, unburned inorganic matter in state of vapour, melts and solid particles are transported in the flue gas and may form deposits on heat transfer surfaces. Deposits on the heat transfer surfaces may result in both increasing corrosion and decreasing boiler efficiency as the heat transfer rate to the superheaters and reheaters decrease by deposits. In order to understand the process of deposit build-up, the whole combustion and transport process had to be analysed including aspects such as, boiler design, fuel properties and combustion environment, followed by particle transport phenomena and the probability for particles to get stuck on the heat transfer tubes. In this thesis numerical simulation of particle trajectories has been conducted as well as measurements of deposits on a special designed deposit probe followed by investigation of on-site measurements of deposit depth on the super-heater tubes in a circulating fluidised bed in Västerås, Sweden. Numerical simulations of particle trajectories in the vicinity of two super-heater tubes were conducted in an Eulerian-Lagrangian mode considering the flue gas and ash particles phase. Particle impingements on the tubes were investigated for different particle sizes. The results from the particle trajectory simulations show that particle larger than 10 µm will mainly impinge on the windward side of the first tube but, however also on the sides of the second tube in the flue gas flow direction. In theory as well as from observations and measurements two tubes can merge together by the deposit build-up. Smaller particles are usually more dispersed due to turbulence and thermophorectic forces, resulting in a more even impingement distribution on the whole surface of the tubes. Probe measurements reveal that the deposit layer growth rate have a significant temperature and time dependence. After the initial deposit build-up a sintering process occurs and sintering is also proven to be dependent on temperature and exposure time. Soot-blowing is the most common method to reduce the effect of deposits on the heat transfer tubes. In the present thesis the soot boiling efficiency is therefore also investigated. The soot-blowing show a strong positive effect on the heat transfer rate in a short time (hours) perspective after a soot-blowing cycle is completed. This positive effect is much weaker when considering a time period of three years. This is an effect of fact that soot-blowing mostly remove the loose part of the deposit material leaving the hard sintered part unaffected. The subject of deposit build up on superheater tubes in large scale boilers involves multi-discipline knowledge and historically, the related research is mostly conducted as measurements and experiments on operating plants. Possibly in the future, theoretical simulations will have a bigger part of research on deposit build-up where the calculations are to be calibrated through measurements on real sites plants.

This Master’s thesis examines the discussions about the new Swedish legal deposit legislation for electronicdocuments, related to Jürgen Habermas’ theories around the public sphere. In 2009, a draft of the law proposal was sent out to various authorities and organizations who were asked tocontribute their views on this matter. This study looks at who has responded of those asked, and what commonviews are apparent within these responses. The responses from two different categories are focused on –universities and other authorities, examining if any similarities or differences can be noticed in the arguments inthe different categories’ responses to the proposed law change. This information has been first analyzed through content analysis, providing an overview to the respondentsof the draft, and the different views which have arisen. Argumentation analysis has then been used to examinehow specific respondents have argued their views, focusing on the National Library of Sweden and the NationalArchives of Sweden. The most common views and arguments revolve around the definitions suggested in the proposal, regardingwhich documents are to be collected and who is responsible for their delivery. Many respondents also mentionedtheir desire to be able to fulfill their legal deposit obligations by delivering documents through networks. Habermas’ theories on the public sphere, which he claims to exist in today’s society, are very similar to thetheories of the public sphere addressed within this study. The authorities and organizations which have beenasked to contribute opinions towards this proposal are the same one who will be directly involved with the legaldeposit itself; while the future users of these collected electronic documents, namely scholars and the public,have been excluded from this discussion. Some respondents remarked upon the importance of the documentsbeing available to those to which they will be of use. However, the discussion has primarily concentrated on howthe delivery of these documents can be affected in the easiest possible manner for those involved.

The Vazante Northern Extension is a continuation of the structurally controlled, hypogene nonsulfide zinc deposit from the Vazante Mine, Minas Gerais, Brazil. The deposit is hosted in Neoproterozoic carbonates of the Serra do Poço Verde Formation located in the Brasília Fold Belt along the western margin of the São Francisco Craton. The Northern Extension deposit is hosted within a shear zone that strikes 200 to 225 and dips 30º-70º NW and is associated with substantial folding that occurred in the same deformation (D2) event and later transcurrent faulting. The shear zone is composed of a tectonic-hydrothermal breccia that can be subdivided into four types: Type 1 Breccia– distally located from the willemite (Zn2SiO4) ore, weakly brecciated dolostone with some Fe-carbonate alteration; Type 2 Breccia–Strong Fe-carbonate alteration, intense brecciation; Type 3 Breccia–hematite replacement breccia, usually proximal to the Type 4 Breccia; Type 4 Breccia–willemite ore breccia, containing three generations of hypogene willemite (Zn2SiO4) as well as hematite (Fe2O3), and franklinite (ZnFe2O4). In the southern part of the deposit, late sulfide-rich veinlets are observed cutting the hypogene zinc silicate mineralization, and contain galena, sphalerite, native silver, covellite, and stromeyerite (Cu1-xAg1-xS). Geochemical studies conducted on the tectonic-hydrothermal breccia showed a strong regional signature enriched in Ag, Cd, Pb, and Zn. The presence of willemite as opposed to sphalerite and the ubiquity of hematite suggest that the zinc silicate mineralization has formed from the mixing between a low sulfur, acid, oxidizing metalliferous basinal brine similar to the fluids found in MVT deposits with a cooler, more oxidizing, meteoric fluid. / Thesis (Master, Geological Sciences & Geological Engineering) -- Queen's University, 2012-02-29 16:45:36.41

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The study investigates the preservation of, and access to, legal deposit materials in South Africa. The rapid development of technology has led to an increase in electronic publications as well as no considerable decrease in the production of printed materials making legal deposit a multifaceted and dynamic area of research. The primary purpose of legal deposit collections is to provide access to materials, both those published recently and produced years ago; these materials are deposited and need to be properly preserved for future generations. The specific objectives of the study were to, examine the activities and strategies in place to preserve materials while being used as well as the accessibility of these documents to the South African population. This study builds on and extends the candidate's investigation carried out in her master‘s thesis in 2007, about how legal deposit materials are kept and preserved. The highlight of the study includes identifying systems that assist with the collection of print and electronic documents. The means and processes to help make both print and electronic documents accessible in the long run are also identified. In addition, the study examines the challenges faced by legal deposit staff including their skills and knowledge in preservation management. The National Library of South Africa (NLSA), Mangaung Library Services, Msunduzi Municipal Library, Constitutional Court Library, R J R Masiea Public Library (Phuthaditjhaba) and North West Provincial Library Services were the units of analysis in this study. The study population included members of the Legal Deposit Committee, the heads of the libraries and departmental heads of legal deposit sections of each library. The whole population was in each case studied. Methodological triangulation was used to look at the problem from different angles using different tools in order to get a more accurate result. The study used both quantitative and qualitative methods, using self-administered questionnaires and interview schedules to collect data. A response rate of 78.6% was achieved for the questionnaire and results were analysed using SPSS. The qualitative method of conceptual content analysis was used to analyse the open-ended questions for the interview schedule. Descriptive statistics were used to summarise data in graphs, tables and pie charts. The major research findings indicate that preservation is not carried out properly at present due to the combined lack of preservation policies, funding, staff training and expertise. Most of the legal deposit libraries do not have preservation policies to improve preservation conditions, develop conservation facilities or to train and recruit staff. Furthermore the study concludes that various critical issues surrounding and affecting all facets of legal deposit stem from a lack of policy. Recommendations based on the findings and conclusions are made and the study establishes that effective implementation, preservation and access of legal deposit are dependent largely on many factors. The most important of these are a proper legislative framework that provides a firm foundation for legal deposit, adequate funding as well as skills and knowledge in preservation management. / Thesis (Ph.D.)-University of KwaZulu-Natal, Pietermaritzburg, 2012.

This dissertation consists of three essays: (I) Double Liability, Moral Hazard and Deposit Insurance Schemes, (II) Contract Costs, Lender Identity and Bank Loan Pricing, and (III) Bank Capital Structure and Differential Lending Behaviour. The first essay proposes to add double liability to a deposit insurance scheme to induce insurees (depository financial institutions) to reveal their true risk types. The second essay looks at the differential lending patterns of American banks versus Japanese banks. The third essay discusses the relationship between the characteristics of a lender and those of the borrower.

Deposit insurance varies greatly across countries due to each country’s specific environment. The purpose of this study is to find what factors may affect coverage limit in deposit insurance. First, we implement panel data over the period of 1960 to 2008 including 78 countries’ political setting, bank industry’s structural differences and overall economic factors. The empirical results show that countries with lower saving rate, interest spread and government debt tend to have higher coverage. However, coverage tends to be lower in more political open countries. Second, we performed panel data logit model to find that increasing government debt would reduce the probability of increasing coverage limits. Third, the regression of variable changes shows strong negative significance in the relationship of interest spread and coverage over GDP per capita. The main contribution of this thesis is to identify significant influences to the coverage limit. This could provide reference factors when considering the setting of Deposit insurance scheme to insure financial stability.

The Mt. Milligan deposit is a tilted (~45°) Cu-Au alkalic porphyry located 155 km northwest of Prince George, B.C., Canada. It is the youngest of the BC alkalic porphyry deposits, all of which formed between 210 to 180 Ma in an extensive belt of K-enriched rocks related to the accretion of the Quesnellia-Stikinia superterrane to ancestral North America. Mt. Milligan has a measured and indicated resource of 205.9 million tonnes at 0.60 g/t Au and 0.25% Cu containing 3.7 million oz. gold, and 1.12 billion lb. copper. Shoshonitic volcanic and volcaniclastic andesites host mineralization. These have been intruded by a composite monzonitic stock (MBX stock), and associated sill (Rainbow Dike). Early disseminated chalcopyrite-magnetite and accessory quartz veins are associated with K-feldspar alteration in the MBX stock. A halo of biotite alteration with less extensive magnetite replaces host rocks within a ~150 m zone surrounding the stock, while K-feldpsar alteration extends along the Rainbow Dike and permeable epiclastic horizons. Peripheral albite-actinolite-epidote assemblages surround the K-silicate zone. Albite-actinolite occurs at depth, and epidote dominates laterally. Copper and Au grade are maximal where the albite-actinolite assemblage overprints biotite alteration. Gold grade is moderate in association with epidote, whereas Cu is depleted. The post-mineral Rainbow Fault separates the core Cu-rich zone from a downthrown Au-rich zone. A similar zonation of metals occurs in the hanging-wall (66 zone), where a Cu-bearing, potassically-altered trachytic horizon transitions to a funnel-shaped zone of pyrite-dolomite-sericite-chlorite alteration with elevated gold. Sulfide S-isotope compositions range from -4.79 δ34S in the central Cu-Au orebody to near-zero values at the system periphery, typical of alkalic porphyries. Sulfur isotope contours reflect the magmatic-hydrothermal fluid evolution, and indicate late-stage ingress of peripheral fluids into the Cu-Au zone. Carbonate C- and O-isotope compositions corroborate the magmatic fluid path from the Cu-Au rich zone to Au-rich zone with decreasing depth. Strontium isotopic compositions of peripheral alteration minerals indicate a laterally increasing meteoric fluid component. Changes in major- and trace element composition of epidote and pyrite across the deposit are also systematic. These provide additional vectors to ore, and confirm the kinematics of the Rainbow Fault.

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