Neste trabalho os parâmetros de fabricação de alvos de dispersão UAlx-Al foram definidos aplicando-se a tecnologia de montagem e laminação de um conjunto núcleo-moldura-revestimentos tradicionalmente adotada na fabricação de placas combustíveis usadas em reatores de pesquisa. O uso das técnicas de dilatometria e difração de raios-x com refinamento de Rietveld contribuíram para desenvolver um processamento termomecânico para controle das fases presentes no núcleo do alvo. Um método inovador que permitiu o aumento da produtividade desse tipo de alvo também foi desenvolvido com base na laminação de múltiplos núcleos. O processo de fabricação mostrou-se adequado para produção de alvos com a especificação para produção de Mo-99 no Reator Multipropósito Brasileiro (RMB). / At this work, the manufacturing parameters of uranium aluminide dispersion targets (UAlx-Al) were defined applying the picture-frame technique, traditionally adopted to manufacture fuel plates used in research reactors. The use of dilatometric and X-ray analysis supported the development of a thermomechanical processing to control the phases present in the target meat. It was also developed a method to quantify uranium aluminides phases. An innovative method that allowed to increase the productivity of this type of target was also developed based on multicore rolling. The manufacturing process proved to be suitable for the production of targets fulfilling the specification to produce Mo-99 in the Brazilian Multipurpose Reactor.

Orientador: Roger J. Zem / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Quimica / Made available in DSpace on 2018-07-27T02:36:46Z (GMT). No. of bitstreams: 1 Santos_LucianaCristinados_M.pdf: 3430679 bytes, checksum: 28d163db7620c9a4ecc0df34b7ae538b (MD5) Previous issue date: 2000 / Resumo: Um novo procedimento de estimativa de área e custos de capital para sistemas sob integração energética é proposto. Este método permite que restrições de troca térmica e trocadores com mais de uma passagem nos tubos sejam utilizados. O método desenvolvido resulta em um modelo não linear onde, balanços de energia, restrições de troca térmica e o fator de correção para trocadores do tipo casco e tubo 1-2 (com 1 passagem no casco e duas ou mais passagens pares nos tubos) são incluídos. As dificuldades de convergência decorrentes da adição de restrições não lineares, devido a utilização de trocadores com múltiplas passagens nos tubos, levaram ao uso de uma estratégia nova. Esta estratégia é constituída pela resolução de dois problemas não lineares. O primeiro estima a área para trocadores contracorrente constituindo a primeira aproximação para obtenção dos fatores de correção para trocadores com múltiplas passagens nos tubos, e outro onde é estimado o capital para trocadores 1-2. Os fatores de correção dos trocadores com múltiplas passagens nos tubos são calculados externamente ao modelo e entram como parâmetro conhecido. Este procedimento é repetido até que uma diferença tolerável entre as estimativas de capital seja atingida. Para completar o projeto de recuperação de energia, uma metodologia que fornece o projeto da rede de trocadores de calor considerando restrições de troca térmica é proposto. O modelo de síntese resulta na formulação de um MIP (Mixed Integer Programming), onde o problema é dividido em estágios e submetido a balanços de energia para minimizar o número de trocadores.Uma comparação dos custos de capital entre os métodos da estimativa de área e o de síntese de rede mostrou bons resultados, já que a diferença de capital entre os métodos foi inferior a 10% / Abstract: A new procedure for estimating area and capital cost targets of constrained heat exchanger networks is presented. The method allows for match constrained networks and exchangers with more than one tube passo The procedure is based on modelling the problem as a non-linear formulation where the forbidden exchanger matches are included as constraints and the temperature difference correction due to multipass exchangers is included in the modeI. The difficulty of converging to a solution due to the additional non-linear constraints imposed by the multipass exchangers required the use of a two-Ievel approach: at the inner leveI, the area targets for simple pass exchangers are obtained, and at the outer leveI the temperature difference required for multipass exchangers are computed and fed back to the inner leveI. The procedure is repeated until an appropriate tolerance between two iterations was achieved. A procedure for the authomatic synthesis of contrained heat exchanger network was developed, using a mixed integer programming approach and minimising the overall number of heat exchangers. A comparison between the estimated exchanger areas and costs estimated by the new procedure and the area and costs obtained from the final heat exchanger design shows a very good agreement / Mestrado / Sistemas de Processos Quimicos e Informatica / Mestre em Engenharia Química

Introduction Alternative methods for producing the medical imaging isotope 99mTc are actively being developed around the world in anticipation of the imminent shutdown of the National Research Universal (NRU) reactor in Chalk River, Ontario, Canada and the high flux reactor (HFR) in Petten, Holland that together currently produce up to 80 % of the world’s supply through fission. The most promising alternative methods involve accelerators that focus Bremsstrahlung radiation or protons on metallic targets comprised of 100Mo and a supporting material used to conduct heat away during irradiation. As an example, the reaction 100Mo(p,2n)99mTc provides a direct route that can be incorporated into routine production in regional nuclear medicine centers that possess medical cyclotrons for production of other isotopes, such as those used for Positron Emission Tomography (PET). The targets used to produce 99mTc are subject to a number of operational constraints. They must withstand the temperatures generated by the irradiation and be fashioned to accommodate temperature gradients from in situ cooling. The targets must be resilient, which means they cannot disintegrate during irradiation or post processing, because of the radioactive nature of the products. Yet, the targets must be easily post-processed to separate the 99mTc. In addition, the method used to manufacture the targets must not be wasteful of the 100Mo, because of its cost (~$2/mg). Any manufacturing process should be able to function remotely in a shielded space to accommodate the possibility of radioactive recycled target feedstock. There are a number of methods that have been proposed for large-scale target manufacturing including electrophoretic deposition, pressing and sinter-ing, electroplating and carburization [1]. How to develop these methods for routine production is an active business [2,3]. From the industrial perspective, plasma spraying showed promising results initially [4], but the process became very expensive requiring customized equipment in order to reduce losses because of overspray,which also required a large inventory of expen-sive feedstock. In this paper we report the ex-perimental validation of an industrial process for production of targets comprising a Mo layer and a copper support. Materials and methods Target Design Targets have been manufactured for irradiation at 15 MeV. Two targets are shown in FIG. 1: one as-manufactured and another after irradiation; no visible changes were observed following irradiation. The supporting circular copper (C101) disks have diameters of 24 mm and thickness of 1.6 mm. The molybdenum in the center of the target is fully dense with thickness 230 μm determined from SEM cross-sections.Targets have also been manufactured for irradi-ation in a general-purpose target holder designed to be attached to all makes of cyclotrons found in regional nuclear medicine centers. The elliptical targets were designed for high-volume production of 99mTc with 15 MeV protons at currents of 400 µA with 15% collimation [4]. The elliptical shape reduces the heat flux associated with high current sources. The cooling channels on the back of the target are designed to with-stand the high temperature generated during Irradiation. A thermal simulation of expected temperatures during irradiation is shown in FIG. 3. The center of the target is expected to reach 260 oC during irradiation. The elliptical targets were formed from a 27 mm C101 copper plate with width 22 mm and length 55 mm. The molybdenum in the center of the target is fully dense with thickness 60 m de-termined from SEM cross-sections. FIG. 4 shows the molybdenum deposition in the center of the target in a form of an ellipse (38×10 mm). Results and Conclusions Circular targets have been produced and suc-cessfully irradiated for up to 5 h with a proton beam with energy 15 MeV and current 50 µA. (FIG. 1). The targets were resilient. Before irradi-ation the targets were subjected to mechanical shock tests and thermal gradients with no ob-servable effect. After irradiation there was no indication of any degradation. The manufacturing process produced 20 consistently reproducible targets within an hour with a molybdenum loss of less than 2 %. After irradiation the targets were chemically processed and the products characterized by Ge-HP gamma spectrometry. Only Tc isotopes were found. No other contami-nants were identified after processing. The de-tails of the separation and purification are de-scribed elsewhere [5]. Circular targets suitable for low-volume produc-tion of 99mTc have been manufactured and test-ed. The targets have been shown to meet the required operation constraints: the targets are resilient withstanding mechanical shock and irradiation conditions; they are readily produced with minimal losses; and post-processing after irradiation for 5 h has been shown to produce 99mTc. Elliptical targets suitable for high-volume pro-duction of 99mTc with high power cyclotrons have been manufactured (FIG. 4). Like the circular targets, the elliptical targets are readily pro-duced with minimal losses and are able to with-stand mechanical shock and thermal gradients; however, they have yet to be irradiated.

The urgent issue of climate change has led to companies increasingly taking climate action by setting science-based emission reduction targets aligned with the goals of the Paris Agreement. The purpose of this study was to investigate how Swedish companies are working to reduce their greenhouse gas emissions through science-based targets. The study was performed through a survey to the Swedish companies committed to the Science Based Targets initiative, and by an assessment of progress against targets using public emission data. The results showed that science-based targets as a tool for climate action raises the climate ambition of companies and provides a good basis for climate strategy. Benefits of committing to science-based targets were primarily that it builds credibility and a good reputation. The main drivers were to improve company climate action, reduce greenhouse gas emissions as well as to gain market advantages. Most companies reported climate results annually, but reporting practices were often insufficient or lacked transparency. Most science-based targets were on track to be achieved, though the results showed more limited progress against targets covering scope 3 emissions. The key activities for progress were primarily linked to energy, transportation and fuel, and product development. Overall, the study shows that science-based targets can play a significant role in companies’ efforts to reduce greenhouse gas emissions and serve as a useful climate action tool. However, increased transparency is needed to strengthen the integrity of the targets.

I årsredovisningar kan företag frivilligt ge ut information utöver det som krävs av regler, principer och praxis. En vanlig typ av sådan frivillig information är målsättningar av olika slag. Men varför olika företag väljer att presentera olika antal målsättningar finns det dock inget tydligt svar på. I tidigare forskning har främst finansiella mål studerats, men då dagens informationssamhälle inte bara fokuserar på finansiella resultat finns en stor del övriga mål som företags intressenter kan komma att efterfråga. Syftet med denna studie är att förklara hur många och vilka målsättningar som börsnoterade företag väljer att redovisa samt förklara vilka samband som föreligger mellan antal målsättningar och variablerna: företagsstorlek, lönsamhet, skuldsättningsgrad, Tobins q och bransch. Denna studie är utförd genom en kvantitativ metod med en deduktiv ansats. Data samlades in från årsredovisningar genom en kvantitativ innehållsanalys. För att mäta sambanden mellan studiens beroende och oberoende variabler utfördes regressions- och korrelationsanalyser. Resultatet visade att 94 % av företagen redovisade någon målsättning, 88 % redovisade finansiella mål och 66 % icke-finansiella mål. Medelantalet för finansiella mål respektive icke-finansiella var 3 per företag. Antal totala målsättningar uppvisade ett positivt samband med företagsstorlek och lönsamhet. För finansiella målsättningar fanns ett positivt samband med skuldsättningsgrad medan icke-finansiella målsättningar inte uppvisade något signifikant samband med någon av variablerna. Även skillnader mellan olika branscher uppvisades, där konsumentvaror hade högst medelvärden, medan energi hade lägst. Dessa förhållanden gällde för målsättningar totalt samt uppdelat på finansiella och icke-finansiella. / In annual reports, companies can voluntarily disclose information that go beyond what rules, guidelines and praxis require. One kind of voluntary disclosure that is commonly occurring is different targets. But there is no distinct explanation to why different companies disclose different number of targets. The subject of earlier studies has mainly been financial targets, but in today’s information society financial results isn’t the only focus. Therefore, stakeholders may also be demanding non-financial information and targets. The aim of this study is to explain the number of and which targets listed companies choose to disclose. The aim is also to explain if the number of targets correlates with the variables: company size, profitability, leverage, Tobin’s q and industry. This study was executed through a quantitative method with a deductive approach. Data was collected from annual reports using a quantitative content analysis. To measure the correlation between the study’s dependent and independent variables, both regression and correlation analysis were performed. The result showed that 94 % of the companies disclosed some kind of target, 88 % disclosed financial targets and 66 % non-financial targets. The average number of financial targets was three per company, likewise for the non-financial targets. The number of targets in total proved to be positively correlated with company size and profitability. The financial targets proved to be positively correlated with leverage, while the non-financial targets didn’t show any significant correlation with any of the variables. Differences between industries were also shown, where consumer goods had the highest mean values, while energy had the lowest. These conditions did apply for the number of targets in total, financial targets and non-financial targets.

Being able to predict a merger or acquisition before it takes place could lead to an investor earning a premium, if they owned shares of the targeted firm before the merger or acquisition attempt is announced. On average acquiring firms pay a premium when acquiring or merging with a targeted firm. This study uses publicly available financial information for 7,267 attempted takeover targets and 52,343 non-targeted firms for the period January 3, 2000 through December 31, 2007 to estimate (using logit) predictive models. Financial ratios are constructed based on six hypotheses found in the literature. Although statistical evidence supports a few of the hypotheses, the low predictive power of the models does not indicate the ability to accurately predict targeted firms ahead of time, let alone with any economic significance.

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There has been an ongoing debate on quality and what constitutes quality improvement in healthcare for several decades. Several authors identify that defining quality is an important part of that debate, yet recognise that quality is defined differently by different interests (Caper, 1988; Harteloh, 2003). Harteloh's distinction between quality as a property (a descriptive approach) and quality as a category of judgment (a prescriptive approach) has influenced the conception of quality as a property of participation emerging in this research. This is in stark contrast to the wide spread prescriptive approach set out in published accounts of quality and quality improvement. In the mainstream management literature, conventionally organisations are understood as systems and this conceptualisation underpins many published considerations of quality. In this way of thinking, those involved in leading quality improvement are thought to operate as autonomous individuals who design improvement tools and control improvements according to plans. It is taken for granted that it is possible for a powerful individual to step out of the organisational system and treat it as an object for manipulation and change, following the diagnosis of problem areas and gaps. Yet at other times that autonomous individual becomes part of the system and is subject to manipulation and change by others. As with much of the literature of change management, this approach sets "thought" before "action". In other words, "thought" is understood as the formulation of a plan and "action" is the implementation of that plan. In this thesis, it is my contention that this way of thinking leads to a privileging of the more mechanical and cybernetic elements of quality improvement - such as tools and techniques of waste elimination and fault detection, and, of particular interest in this thesis, the use of national targets in the public sector. My research is underpinned by a complex responsive processes perspective (Stacey, Griffin and Shaw, 2000). Central to this theory of human interaction is the importance of understanding everyday experience from the perspective of inquiring into “…just what is it that we are doing in our groups or in our organisations that leads to emergent patterns that are our experience…” (Stacey, 2003c: 32). In this thesis, I take up a key question raised by Stacey (2006) concerning how those working in the public sector institutions are operationalising central government governance requirements. I explore my experience of working locally with nationally determined performance targets for access to emergency care. I argue for consideration of quality improvement as a cult value along the lines defined by Mead (1923). In conceptualising quality improvement in this way, my inquiry focuses on what happens as we try to make sense of the ways in which our daily activities are being influenced by competing ideologies, by power relations that are played out, and by the enabling and constraining aspects of going on together in patterns of conversation. These are the complex social processes of working with targets I refer to in the title of this thesis. It is my contention that this perspective draws attention to quality as a property of our own participation as managers, rather than the more usual exhortations to look for the next tool for instilling quality into the organisation. As such, I argue that this research makes an important contribution to the ongoing debate on quality, as well as managerial practice. I propose that the participative and socially reflexive nature of the qualitative methodology involved provides a practical example of Mode 2 research, addressing what MacLean, MacIntosh and Grant (2002) identify as a current gap in the literature. Finally, I posit a potential contribution to policy making seeking to address a growing recognition from some policy makers regarding what is now being seen as an increasing problematic reliance on traditional, modernist assumptions of programmatic change.

The bacterium Burkholderia pseudomallei causes the disease melioidosis, a significant public health threat in endemic regions and is a potential biowarfare agent. Treatment of melioidosis is intensive and prolonged and there is no licensed vaccine to protect against it. The aim of this study was to characterise novel targets for antimicrobials to improve treatment of melioidosis. A holistic down selection process was undertaken in order to identify a range of possible novel and exploitable antimicrobial targets in Burkholderia pseudomallei. Four targets: FtsA, FtsZ, MraW and TonB were selected for characterisation by mutagenesis study. FtsA and FtsZ are early effectors of cell division and are considered potential antimicrobial drug targets in other pathogenic bacteria. Genes for both were shown likely to be essential for viability in Burkholderia pseudomallei, following attempted deletion of the genes, thus confirming their potential for drug targeting for treatment of melioidosis. MraW, a highly conserved methyltransferase, and TonB, the energiser for high affinity iron uptake in Gram negative bacteria, were also selected for characterisation as antimicrobial targets. In-frame deletions of the genes encoding these targets were constructed in B. pseudomallei K96243. In order to determine the roles played by MraW and TonB during infection, these mutants were characterised in several models of Burkholderia pseudomallei infection. Deletion of mraW rendered the bacteria non-motile and led to attenuation during infection of Balb/C mice. A small growth defect was seen early during infection of macrophages by this mutant, whilst no attenuation was seen on deletion of mraW in Galleria mellonella. Burkholderia pseudomallei ΔtonB required free iron supplementation for growth. This mutant had an improved ability to invade murine macrophages, though the mutant was attenuated in both Galleria mellonella and Balb/C mice. Attenuation of both mutants in a mammalian model of infection, support the strategy to target either of these proteins as novel targets for inhibition with small molecules during Burkholderia pseudomallei infection. However, an improved ability to infect macrophages by Burkholderia pseudomallei ΔtonB and non-complementation of this mutant by iron supplementation to Galleria mellonella suggests additional roles to iron uptake alone for TonB in Burkholderia pseudomallei, such as bacterial iron sensing and signalling.