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Challenges surrounding energy have gained increased attention, which is not least reflected in the 2030 Agenda for Sustainable Development and the Sustainable Development Goals (SDGs). Energy issues have also become a pressing matter for most countries in the last decades. The reasons for this are not only related to the effects of the emission of greenhouse gases (GHG) from fossil fuels and their impact in climate change, but also span through other issues such as security of energy supply with geopolitical considerations and competitiveness of industry. To address these issues, a collection of public policies ranging from the international to local levels have been implemented. Sweden has historically had lower energy prices than its European counterparts, which has resulted in its industry having a relatively higher share of electricity in the total energy use by industry. The share of electricity accounts for 35% of total energy use in Swedish industry. This has led to efficiency measures being overlooked by industry, and the pulp and paper industry is by far the biggest energy user, with a share of 51% of the total energy use by industry. The variation of energy prices, and particularly electricity prices have obvious implications on the competitiveness of this sector. Production of biogas in pulp and paper mills has been gaining attention, and is now the target of an increasing number of scientific studies. The interest for this industry is not only related to security of energy supply and the environmental performance of the biogas itself, but there are also considerations regarding the biogas plant as an alternative to treat the large flows of wastewaters and other waste stream in this sector. There is an estimated biogas production potential of 1 TWh within this industry in Sweden, which accounts for 60% of the current biogas production in the country. Pulp and paper mills commonly rely on aerated biological treatment to deal with waste streams with high organic content This biological process has a high energy demand, and the integration of an anaerobic treatment, along with the use of the biogas for heat and electricity can yield a net positive energy recovery for the combined plant. This project analyses the current energy and material performance of an anaerobic biological treatment combined with an aerobic biological treatment in a recycled board mill. The anaerobic treatment is performed upstream of the aerobic one and removes most of the chemical oxygen demand of the wastewater. Energy and material balances for the plant are presented, and a comparison of the wastewater treatment plant running before and after the start-up of the biogas plant is made. The plant operation with the anaerobic digestion has shown an increased energy use of 9.4% coupled to an increased flow of wastewater of 7.7%. The average biogas production is 72 Nm³/h, which accounts for 440 kWh and is currently being flared. The introduction of AD has largely decrease the organic load in the aerobic treatment, by nearly 50%. This project ends with an optimisation model implemented with the optimisation tool reMIND to investigate potential optimisation strategies for the operation of the combined plant. The model has shown to be adequate to describe electricity use with mean error below 10%. For the biogas production, the mean error was of 16%.

Master of Landscape Architecture / Department of Landscape Architecture/Regional and Community Planning / Lee R. Skabelund / Since the mid-1960s a paradigm shift in environmental values has been initiated in Europe, parts of the United States, and many other parts of the world, culminating in a focus on green infrastructure based development (Ahern et al., 2007b). During the 1980s and 1990s sustainability and landscape ecology began to be important aspects of landscape architecture education and practice (Swaffield, 2002; Ahern, 2005). The effort to create sustainable cities, neighborhoods, and sites is making a difference in urban areas, which is very important since global census data shows that a majority of the earth’s population now lives in urban settlements (United Nations, 2014). Personal and cultural values reveal an environmental consciousness and strong interest in sustainability in many communities (Peiser & Hamilton, 2012). Nevertheless, many developments associated with landscape construction seem to implement few, if any, sustainable practices as new neighborhoods in many parts of the U.S. are developed. This study develops a modified ecological approach and applies this outlook to an existing exurban neighborhood in Manhattan, Kansas. Quantitative and qualitative research includes: 1) a review of relevant literature and precedent studies; 2) a multi-tiered site analysis informed by landscape ecology principles; and 3) surveys of local homeowners regarding landscape maintenance practices and their willingness to install more ecologically appropriate landscapes. It is anticipated that sustainable design considerations for Lee Mill Heights and nearby areas will emerge to inform future neighborhood retrofits, helping move existing subdivisions towards more ecologically appropriate patterns and processes.

Thesis advisor: Zhifeng Ren / Solid state cooling and power generation based on thermoelectric principles are regarded as one of the technologies with the potential of solving the current energy crisis. Thermoelectric devices could be widely used in waste heat recovery, small scale power generation and refrigeration. It has no moving parts and is environmental friendly. The limitation to its application is due to its low efficiency. Most of the current commercialized thermoelectric materials have figure of merit (ZT) around 1. To be comparable with kitchen refrigerator, ZT is required at room temperature. Skutterudites have emerged as member of the novel materials, which potentially have a higher ZT. In the dissertation, my investigation will be focused on the optimization of CoSb₃ &ndash based skutterudites. Starting with Co and Sb elements, CoSb₃ will form through a high energy ball mill. Unfortunately, even after 20 hours, only a small percentage of the powders have transformed in into CoSb₃. Then the powders will be compacted into bulk samples by DC-controlled hot press. CoSb₃ single phase will form after press. Characterization of the structure and thermoelectric properties will be presented with details. The effects of synthesis conditions on thermoelectric properties of skutterudites were studied and discussed. Several possible methods of improving the ZT of N type skutterudites were applied. The highest obtained ZT thus far is about 1.2 from Yb doped CoSb₃. For a group of samples with nominal composition Yb_xCo₄Sb₁₂, the increased Yb concentration in our samples not only enhanced the power factor due to electron doping effect but also decreased the thermal conductivity due to a stronger rattling effect. In addition, the increased grain boundary density per unit volume due to the small grains in our bulk skutterudite materials may have also helped to enhance the phonon scattering and thus to reduce the thermal conductivity. Single and double doping methods with different combinations were also tried. So far, none of them have surpassed ZT of 1.2. Mixing different materials with Yb_0.35Co₄Sb₁₂ so far to increase the phonon scattering was also performed. No dramatic thermal conductivity reduction was observed. Small amounts of Fe/Mn substitution on Co sites will decrease the power factor to undesired degrees. Some results with Nd filled P type sample will be briefly introduced. P type samples are also obtained through substitution on Sb site. Preliminary work on preparing the electrode for CoSb₃ will be presented in the dissertation. CoSi₂ has low resistivity, and a similar coefficient of thermal expansion (CTE) as of doped CoSb₃. It is good electrode candidate. DC controlled hot press is used to make the contact. Thermal stability of the contact was tested. Small cracks will form in the contact area, further improvement is necessary. Finally, my previous work on ZnO nanowire growth is briefly introduced. Large throughput of ZnO nanowire could be obtained with NaCl as the support to promote the conversion of Zn powder to ZnO. / Thesis (PhD) — Boston College, 2010. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.

Na área de moagem secundária, ou remoagem, a preocupação com a eficiência energética se mostra de extrema importância. Em geral, os consumos específicos desta etapa são superiores aos da etapa primária. Além disso, tem se observado uma tendência de afinamento das granulometrias de moagem nos novos projetos de minerais metálicos, o que leva cada vez mais a uma maior necessidade de gastos nesta etapa, tanto em termos de custos de implantação como de operação. Nos novos projetos que incluem remoagem no Brasil granulometrias de remoagem da ordem de 40 a 20 m têm se mostrado necessárias. Neste contexto, os moinhos tubulares de bolas, adequados para moagem primária, apresentam eficiências decrescentes em termos de aproveitamento de energia, quando são necessários produtos abaixo de 50 m. A fim de avaliar as melhores alternativas tecnológicas disponíveis para estas aplicações de remoagem, este trabalho estudou moinhos de carga agitada, com foco em moinhos verticais. O presente trabalho apresenta e discute os resultados de amostragens em escala industrial com o moinho vertical em quatro usinas em operação no Brasil. Foi desenvolvido também um novo ensaio em escala laboratorial para simular o consumo de energia e a distribuição granulométrica dos moinhos verticais, que se mostrou válido para a aplicação estudada. / Energy efficiency is extremely important in secondary grinding (regrinding) as specific consumption are greater than obtained in primary grinding. Moreover, finer grinding sizes are a trend in new grinding circuits therefore increasing the energy consumption, as well as respective capital and operating costs. In Brazil regrinding sizes between 40 a 20 m are common in greenfield projects. As horizontal ball mills show decreasing efficiency as grinding sizes are finer than 50 m, this work shows regrinding equipment alternatives to ball mills focusing on vertical mills. A number of survey campaigns were carried out on four industrial operations in which vertical mills were installed in the respective regrind circuit. A new batch test was developed and validated to predict the energy consumption and product size distribution associated to vertical mills.

Os caranguejos anomuros da família Lithodidae são exclusivamente marinhos, habitantes predominantemente de águas frias vivendo, geralmente, em águas profundas. Via de regra são animais de grande tamanho, sendo que das 124 espécies atualmente conhecidas (distribuídas em 10 gêneros), algumas são de grande importância comercial. O monofiletismo da família Lithodidae e dos gêneros que a compõe, assim como as relações filogenéticas em Lithodidae ainda são obscuros e têm recebido muito pouca atenção. Diante da complexidade do esqueleto gástrico nos crustáceos Decapoda, neste trabalho nós investigamos em detalhe as características morfológicas dos ossículos do esqueleto gástrico em Lithodidae com vistas a sua descrição, interpretação e como fonte de dados morfológicos para servir de base a uma análise filogenética de Lithodidae, cujo objetivo precípuo foi testar a hipótese de monofiletismo de Lithodidae e acessar as relações internas na família. A partir do estudo de 185 estômagos foi descrita e ilustrada a morfologia dos ossículos do esqueleto gástrico de 66 espécies: 52 espécies (dos 10 gêneros de Lithodidae), 8 espécies (dos 5 gêneros de Hapalogastridae) e 6 espécies de outros Decapoda representantes do grupo externo (Birgus latro, Petrochirus diogenes, Pagurus bernhardus, Homarus americanus, Nephrops norvegicus e Thalassina anomala). A análise cladística de Lithodoidea foi realizada no programa TNT. Foram utilizados 126 caracteres binários e 63 caracteres multiestado obtidos da morfologia do esqueleto gástrico, relacionados com o tamanho, forma, grau de calcificação, grau de fusão de ossículos e morfologia dos dentes gástricos. O esqueleto gástrico em Lithodoidea está composto por 44 ossículos. Um novo ossículo foi reconhecido, o parapterocardíaco, associado com o ossículo pterocardíaco. A maioria dos ossículos exibem um padrão uniforme com variações menores e elementos morfológicos característicos. Nossa análise cladística resultou em 10 árvores igualmente parcimoniosas com 1802 passos. Nosso estudo mostra que a superfamília Lithodoidea é monofilética, porém o monofiletismo de Lithodidae e Hapalogastridae não pode ser recuperado. Os gêneros de Lithodidae, Cryptolithodes e Lopholithodes são monofiléticos, enquanto que Lithodes, Neolithodes, e Paralomis são polifiléticos. Paralithodes é parafilético. Os gêneros monoespecíficos de Lithodidae (Glyptolithodes, Phyllolithodes, Rhinolithodes e Sculptolithodes) são bem caracterizados por autapomorfias. Em consequência de nossos resultados, alterações na classificação interna de Lithodoidea são necessárias, afim de refletir as relações evolutivas. / The king crabs of the family Lithodidae (Anomura) are all marine and inhabit predominantly cold, deep waters. The lithodids currently comprise 124 species, some of which attain large sizes and are of great commercial importance. The interrelationships of the lithodids and even their monophyly and some of the constituent genera are yet to be solved. The great complexity of the decapod gastric mill prompted us to study the morphology of the gastric ossicles in the Lithodidae as a source of characters to assess its phylogenetic interrelationships and its monophyletic status as well as that of its constituent genera. We described and illustrated herein the morphology of the gastric ossicles from 66 species. A total of 186 stomachs were obtained as follows: 52 lithodid species (from all the 10 genera currently included in the Lithodidae), 8 hapalocarcinid species (from all the 5 genera of the Hapalogastridae) and 6 species from other groups of decapods representing the outgroup (Birgus latro, Petrochirus diogenes, Pagurus bernhardus, Homarus americanus, Nephrops novegicus e Thalassina anomala). The cladistic analysis of the Lithodoidea, was performed using the program TNT. 126 binary and 63 multistate characters from the morphology of the gastric ossicles related to size, shape, degree of calcification and fusion between ossicles, were used. The stomach of the Lithodoidea consists of 44 ossicles. A new ossicle is recognized herein, the para-pterocardiac, associated with pterocardiac ossicle. Most of the ossicles are conservative in shape, with few variations and distinctive morphological elements. The cladistic analysis resulted in 10 equally parsimonious trees with 1802 steps. Our study show that the superfamily Lithodoidea is monophyletic, whereas the lithodids and hapalogastrids were not recovered as monophyletic groups. The lithodid genera Cryptolithodes and Lopholithodes was recovered as monophyletic, while Lithodes, Neolithodes and Paralomis are polyphyletic; Paralithodes is paraphyletic. The monospecific lithodid genera are well characterized by a number of autoapomorphies each. As a result, the internal classification of the Lithodoidea requires further elaboration in order to reflect evolutionary relationships.

Sistemas de geração de referências para as malhas de controle de laminadores a frio têm proporcionado elevados níveis de produtividade e de qualidade do material processado. No caso de falha da unidade de processamento responsável pela execução do sistema de geração de referências, a operação do laminador fica comprometida e necessita-se de um modo de operação emergencial. Nesse trabalho é desenvolvido um sistema alternativo para geração de referências que visa substituir o modo de operação de emergência de consulta a tabelas de referências pré-calculadas da planta em questão. O sistema de geração de referências desenvolvido, assim como o sistema usado em condições normais de operação, é composto por uma função custo que avalia o nível de produtividade e de qualidade que um conjunto de referências pode proporcionar. A função custo é minimizada pelo método simplex de Nelder e Mead e as variáveis do processo envolvidas na função custo são avaliadas por um modelo de laminação a frio composto somente por equações algébricas, enquanto que o sistema usado em condições normais de operação usa um modelo clássico, composto por equações algébricas e integrais. A comparação entre o sistema usado em condições normais de operação e o sistema desenvolvido mostrou que apesar desse sistema ser mais simples, menos preciso e robusto, as referências por ele calculadas são aceitáveis e podem proporcionar resultados superiores que o modo de operação de emergência baseado na consulta a tabelas. / Setup generation systems for cold mill control loops have provided rolling mill operation with high levels of quality and productivity. In case of malfunctioning in the process unit responsible to execute the setup generation system, the normal procedure for the operation of the mill is interrupted, being necessary the use of an emergency operation mode. This work develops an alternative system for references generation which aims to replace the current emergency operation mode based on pre-calculated, not continuous, setup tables for the rolling mill. The developed references generation system, like the normal system used during mill operation, is composed by a cost function which evaluated the mill quality and productivity operation level which a set of references may propose. The cost function is minimized using the Nelder and Mead simplex method and the process variables involved in the cost function are evaluated by a cold rolling mill model composed only by algebraic equations, while the normal operation system uses a classical model, made up by integrals and algebraic equations. Comparing the existing main setup system to the developed reference system it was observed that, despite its simplicity, less accuracy and less robustness, references calculated using this system were accurate enough to achieve better results than the one emergency table mode has provided.

Nos tratamentos ortodônticos, fios de diferentes ligas metálicas são utilizados nas etapas de alinhamento, nivelamento, correção da posição molar, fechamento espacial, acabamento e retenção. Com relação às duas últimas, responsáveis pelo posicionamento adequado dos dentes superiores sobre os inferiores, a preparação requer um fio que favoreça o torque de incisão, ou seja, que apresente grande resistência e rigidez associadas à ativação de pequeno alcance. Para este fim, os fios de aços inoxidáveis austeníticos retangulares são os preferidos em razão do módulo de elasticidade elevado e boa resistência à corrosão no meio bucal. Quanto à geometria retangular, o processo de fabricação requer desenvolvimento tecnológico adequado para a produção em escala industrial de fios com as características geométricas e propriedades mecânicas para melhor adequação às necessidades de uso. Com o objetivo de se produzir fios com tais características, foi desenvolvido um laminador para a fabricação de fios retangulares com a intuito de se dispor de uma alternativa de menor custo ao processo de produção por trefilação, de custo elevado, devido a complexidade das matrizes. Além da fabricação do laminador, foram avaliados os aspectos tecnológicos que envolveram os efeitos da deformação nas propriedades mecânicas dos fios, por meio de medidas de microdurezas e ensaios em tração e de flexão. Nos testes realizados, os fios apresentaram geometria, acabamento superficial e propriedades mecânicas adequadas à sua utilização em tratamentos ortodônticos. / In orthodontic treatments, wires of different metallic alloys are used for alignment, leveling, correction of the molar position, space closing, finish and retention. With respect to finish and retention, these wires are responsible for adequate positioning of the upper teeth on the lower teeth. Wires that are subjected to incisor torque require high resistance and stiffness. For this, wires of rectangular austenitic stainless steel are used due to high modulus of elasticity and good corrosion resistance in the oral environment. Because of the rectangular geometry, wire production requires process development suitable for industrial scale manufacture with geometric characteristics and mechanical properties better adapted to the use conditions. To obtain wires with such characteristics, a rolling mill was developed for the production of rectangular wires by a rolling process with the objective of reducing cost of the cold drawing process that is currently used, which utilize complex and expensive wiredrawing dies. In addition to the rolling process itself, wire deformation, microhardness, tension and bend tests were also performed. In these tests, wire geometry, surface finish and mechanical properties were successfully adapted for use in orthodontic treatments.

The pulp and paper industry in New Zealand annually produces over one hundred thousand dry tonnes of solid waste due to the treatment of pulp and paper mill effluents, the majority of which is currently landfilled. The New Zealand Waste Management Strategy (2002) has set a target for the diversion of commercial organic wastes from landfill to beneficial use to exceed 95% by 2010 . Effluents produced by softwood pulp mills, such as in New Zealand, contain high concentrations of naturally derived resin extractive compounds that are toxic to fish and other aquatic organisms. Improvements in waste water treatment technology has enabled the industry to meet rigorous discharge standards, however, this has resulted in an increase in the production of pulp mill effluent solids which require disposal. This has become an issue for the pulp and paper industry, especially as current landfill space is limited. Land application has been used for many years as a means of disposal of pulp mill wastes. While most studies investigating land application of pulp mill effluent solids have concluded that the risk posed to the environment is low, few have investigated the potential toxicity of these wastes to soil organisms, and these studies did not directly address the effects of resin extractive compounds. Resin extractives have been shown to be recalcitrant and to accumulate in anaerobic sediments. It is not known to what extent resin extractives are bioavailable or degradable in land applied Pulp mill effluent solids (PMES), or their potential to bioaccumulate in soil organisms. This PhD thesis research sought to extend the knowledge on the environmental fate and effects of pulp mill effluent wastes. It focused on terrestrial systems, which have not been well studied in this respect. Four chemically distinct softwood pulp mill effluent solids, a primary treatment solid and three secondary treatment biosolids, were used to investigate their effects on soil organisms and soil functions. An interdisciplinary approach was adopted, which incorporated three main areas of study, as follows: 1. A comprehensive resin extractives analysis of the pulp mill effluent solids undertaken so that effects on soil organisms and soil functions could be related to the resin extractives chemistry of the individual pulp mill effluent solids tested. 2. A battery of bioassays used to investigate the toxicity of the selected pulp mill effluent solids. 3. A field trial set-up to investigate how pulp mill effluent solids affected soil functions and also to investigate the decomposition of pulp mill effluent solids and of resin extractives in these solids. Three hypotheses tested were: I. Pulp mill effluent solids are toxic to soil organisms. II. Resin extractives in pulp mill effluent solids are recalcitrant in the terrestrial environment. III. Pulp mill effluent solids will cause significant measurable negative impacts on soil functional capacity. A wide range of resin extractives compounds were identified in pulp mill effluent solids, and concentrations of individual compounds varied widely between the different pulp mill effluent solids tested. During the two years after field application of the pulp mill effluent solids, resin extractives declined, however, decay rates of individual compounds were variable. The decay rate of compounds was influenced by the type of pulp mill effluent solids containing these compounds and not by the initial concentration of compounds. All compounds, including resin acids, degraded rapidly in the applied primary solid and in one of the applied biosolids, with average half-lives calculated ranging from three to twelve months. In the other biosolids, resin acids were recalcitrant with average half-lives calculated to be nearly ten years. Laboratory bioassays conducted on oats, earthworms and enchytraeid worms indicated that pulp mill effluent solids had low toxicity to these organisms. An aquatic bioassay organism, however, was acutely affected by aqueous extracts from pulp mill effluent solids. Earthworms were shown to bioaccumulate some resin extractive compounds to a limited extent, indicating that resin extractives were bioavailable in pulp mill effluent solids. Enchytraeid reproduction was reduced by exposure to some pulp mill effluent solids but this was not correlated to resin extractives concentration of the solids tested. Field applied pulp mill effluent solids significantly enhanced the fluxes of CO2 from the soil surface. When mass losses of pulp mill effluent solids carbon were taken into account, it was shown that these solids had little effect on soil respiration. Needle litterbags were placed above and below pulp mill effluent solids and in the litter horizon of a control treatment for 12 months. Needle litter decomposition was not significantly different between treatments, however, changes in enzyme activities were detected in litter beneath pulp mill effluent solids compared to control needle litter that had not been exposed to pulp mill effluent solids. The decomposition rate of field applied pulp mill effluent solids was slow, with half-lives extrapolated to be between five and twenty five years. The decomposition rate appeared to be influenced by the pools of carbon available for decomposition, with primary solids decaying significantly faster than biosolids due to a higher cellulose component. The conclusions of the PhD thesis research are, therefore, that generally, pulp mill effluent solids used in the study were demonstrated to be relatively benign and appear to pose a low risk to the terrestrial ecosystem when applied to soil. However, a cautious approach is still recommended to land application, based on the extensive evidence of disruption to aquatic ecosystems, and because pulp mill effluent solids will take many years to decompose and resin acids are recalcitrant in some pulp mill effluent solids. Further research is recommended to elucidate mechanisms of action by resin extractives in soil organisms and the ultimate fate of these compounds in the soil compartment.

The ideas of liberty presented in the important works of John Locke and John Stuart Mill, The Second Treatise of Government (1689) and On Liberty (1859), are often viewed as belonging to the same conceptual tradition, that of English liberalism. This thesis is an articulation of the diversity between the theories of liberty expressed by Locke and Mill in the Second Treatise and On liberty. \ am aiming to provide a corrective to the tendency to ignore or to gloss over very significant differences between the two men. The work concentrates on the philosophical aspects of each theory of liberty, arguing that they differ in four respects. These are; definitions of liberty; justifications of liberty; how much liberty and for whom they recommend it, and finally, who they believe threatens liberty and how this threat is to be curbed. It is the purpose of this thesis to show that in terms of these areas Locke and Mill are pursuing different ends. I conclude that Locke and Mill present strikingly different theories of liberty and cannot be thought of as belonging to the one conceptual tradition in terms of the definition, the justification, the prescription and the threat to liberty. Ultimately, I question the value of including Locke and Mill in the one conceptual tradition of liberty solely on the basis that they argue ‘freedom from.’