<p>The Vickers residual stress field (VRSF) in soda-lime glass results from the elastic-plastic contact event that takes place when a Vickers diamond pyramid is loaded onto the surface of the material in an indentation cycle. The importance of elastic-plastic indentation lies in the contact damage that it gives rise to in the surface of the glass. Since such surface flaws can be characterised, with respect to shape and size, they offer the opportunity to study naturally occurring flaws in glass and brittle materials in general. The residual stress field is not passive; rather it exerts a crack opening force on the associated crack system during subsequent strength testing of a Vickers-indented sample through a residual stress field coefficient, c. Besides the strength-controlling properties, the elastic-plastic contact residual stress field is also important as a region where the influence of mechanical excitation on material properties such as hardness, H, and elastic modulus, E, can be studied.</p><p>This thesis concerns studies that were made to characterise the Vickers residual stress field by first measuring the magnitude and distribution of stresses around it, using nanoindentation with a cube corner tip. With a Berkovich tip in nanoindentation, experiments were conducted in the VRSF to study the dependence of hardness, H and elastic modulus, E, on stresses in soda-lime glass: a strong E dependence on stress was observed, while H was not affected unless the stresses were high. In the process, a method was developed to determine the true contact area during elastic-plastic nanoindentation when the Oliver-Pharr method is used for the data analysis.</p><p>The observed elastic modulus dependence on stress was then utilised in a study where it was shown that the VRSF responds differently to relaxation annealing on either side of the glass transition temperature. This result was then used to explain strength recovery trends in annealed Vickers-indented glass specimens.</p>

Summary                                                               Overweight and obesity in Sweden and in the rest of the industrialized world continues to increase. This results in increased costs both to society and the healthcare system. Part of this development is the increasing consumption of sugar and that is what should be restricted to tackle this growing social problem. Part of the increased consumption of sugar in Sweden was the launch of pick and mix ingrocery stores.  This study aims to examine how store managers look at their public health responsibilities, and investigate how managers of grocery stores think about health and health aspects in general and about the sugar consumption in particular. Semi-structured "face to face" interviews was used to collect data and seven grocery store managers participated in the study. The interviews were analyzed using concentration of sentences that involves compiling the interviewees' statements into shorter formulations. Results of the study showed that all the store managers claimed to take the health responsibilities that can be expected of them. The health aspects taken into account by the store managers were that they provided good organic and locally produced groceries and that some of them had collaboration with a dietician or people with other professions related to food. It was considered easy to buy good and healthy food by all store managers. The question regarding the introduction of a sugar tax divided the store managers, 4 of them were positive to taxation, while 3 of them were more hesitant about its effects. The conclusion of this study is that store managers are taking some responsibility to the public health by providing healthy alternatives. However there is much more they can do to reduce sugar consumption among the population, thus contributing to an important public health work.

Thesis (M.B.A.)--University of Hong Kong, 1997. / Includes bibliographical references (leaf 71-74).

Made available in DSpace on 2014-06-11T19:32:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-09-18Bitstream added on 2014-06-13T20:43:10Z : No. of bitstreams: 1 algazi_adf_dr_jabo.pdf: 940112 bytes, checksum: 2ed564ef1af617edc20e4563d7fa8fa4 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Metriona elatior Klug é potencial candidato para o controle biológico de Solanum viarum Dunal (joá-bravo), principalmente em locais onde está planta é caracterizada como invasora e exótica. A especificidade é um forte requisito para a adequabilidade de um organismo como agente de controle biológico. Assim, a preferência alimentar das diferentes fases de desenvolvimento desse inseto em laboratório, foi avaliada em quatorze híbridos de Solanum melogena Linnaeus (berinjela). Adicionalmente, foi realizado à análise citogenética do inseto e do joá-bravo. O estudo iniciou-se pelos testes de dupla e múltipla escolha, em períodos de exposição de 24 e 48 horas, oferecendo discos de tecido foliar, em condições de placas de Petri. As avaliações da sobrevivência e consumo foliar das larvas e adultos (recém emergidos e sem distinção sexual) foram realizadas em folhas de joá-bravo e nos híbridos de berinjela mantidas túrgidas pela imersão do pecíolo em água. A área foliar foi medida antes e após quatro dias de exposição ao inseto e a longevidade avaliada através de observações diárias. Os adultos e as larvas de M. elatior apresentaram maior taxa de alimentação, sobrevivência e consumo na planta daninha. Dentre os híbridos comercias, Minikuro Kowishiki e Redonda Wase Oomaru foram mais preferidos pelos adultos e larvas, respectivamente, do crisomelídeo em estudo. No entanto, estes dados são preliminares para teste de risco. As análises citogenéticas permitiram quantificar o número cromossômico de 2n = 24 para ovos de M. elatior e 2n = 18 nas raízes de S. viarum. / Metriona elatior Klug is a potential agent for the biological control of Solanum viarum Dunal (tropical soda apple), especially in regions where this plant is an exotic and invasive plant. Feeding specificity is an important requirement for the adoption of an organism as a biological control agent. The feeding preference of this insect at different development stages was tested under lab conditions in fourteen Solanum melogena Linnaeus (eggplant) hybrids and S. viarum. In addition, a cytogenetical analysis was performed in tropical soda apple and the insect. The study started with dual and multiple choice testes with exposure times of 24 and 48 hours, by providing leaf disks to insects in Petri dishes. Survival and leaf consumption of larvae and adults (nearly emerged, regardless of sex) were determined in tropical soda apple and eggplant leaves kept turgid by petiole immersion in water. Leaf area was measured before and after four days of exposure to the insect while longevity was determined through daily observations. M. elatior adults and larvae showed higher feeding, survival and consumption rates on the weed specie. The eggplant commercial hybrids Minikuro Kowishiki and Redonda Wase Oomaru were the most preferred by adults and larvae, respectively. However, results are still preliminary for a risk test. Cytogenetical analyses allowed us to count the chromosome number of M. elatior (2n = 24) in eggs and S. viarum (2n = 18) in roots.

Submitted by Lucienne Costa (lucienneferreira@ufcg.edu.br) on 2018-04-24T00:19:47Z No. of bitstreams: 1 JULIANA ZEYMER AUAD PAFFER – DISSERTAÇÃO (PPGEQ) 2015.pdf: 2369945 bytes, checksum: 31ce517399cfe89bebdd0e7c02c68852 (MD5) / Made available in DSpace on 2018-04-24T00:19:47Z (GMT). No. of bitstreams: 1 JULIANA ZEYMER AUAD PAFFER – DISSERTAÇÃO (PPGEQ) 2015.pdf: 2369945 bytes, checksum: 31ce517399cfe89bebdd0e7c02c68852 (MD5) / Um dos efluentes gerados na indústria de cloro e soda é uma corrente ácida (água saturada de cloro). Esta corrente deve passar por um sistema de tratamento antes de ser descartado, devido ao potencial de dano que este pode causar à flora e à fauna marinha, além de infringir as regulamentações ambientais. Visando reduzir o consumo de energia e atender à especificação do efluente, o objetivo deste trabalho é realizar e avaliar a simulação dinâmica de um sistema de tratamento de efluente ácido. O sistema estudado é composto por uma coluna de stripper e um trocador de calor que pré aquece a corrente de alimentação. O estudo se concentrou em avaliar o comportamento do sistema no estado estacionário e dinâmico frente a alterações nas condições de operação do trocador de calor. As simulações foram realizadas no AspenTM e validados com dados da planta industrial. De acordo com os resultados, reduzindo a eficiência de troca de calor do trocador leva no aumento do consumo de energia e o efluente fica fora das especificações. Desta forma, é muito importante manter a eficiência do trocador de acordo com a de projeto e os controladores sintonizados. / One of the effluents generated by chlor-alkali plant is an acid stream (saturated water chlorine). This stream must pass through a treatment system before being discarded because of damage potential that this may cause to the flora and marine fauna, in addition to breaching environmental regulations. In order to reduce energy consumption and meet the effluent specification, the objective is to implement and evaluate the dynamic simulation of an acid wastewater treatment system. The system is composed of a column stripper and a heat exchanger that heats the pre feed stream. The study focused on evaluating the system behavior in the steady state and dynamic against changes in operating conditions of the heat exchanger. The simulations were accomplished by the simulator Aspen™ and validated with data from industrial plant. According to the results, reducing the efficiency of heat exchanger can make the power consumption increase and the effluent is out of specification. This way, it is very important to keep the heat exchange efficiency according to design and tuned controls.

The radio spectrum dependent applications are facing a huge scarcity of the resource. To address this issue, future wireless systems require new wireless network architectures and new approaches to spectrum management. Spectrum sharing has emerged as a promising solution to address the radio frequency (RF) spectrum bottleneck. Although spectrum sharing is intended to provide flexible use of the spectrum, the architecture of the existing approaches, such as TV White Space [1] and Citizen Broadband Radio Services (CBRS) [2], have a relatively fixed sharing framework. This fixed structure limits the applicability of the architecture to other bands where the relationship between various new users and different types of legacy users co-exist. Specifically, an important aspect of sharing that has not been explored enough is the cooperation between the resource owner and the opportunistic user. Also in a shared spectrum system, the users do not have any information about the availability and duration of the available spectrum opportunities. This lack of understanding about the shared spectrum leads the research community to explore a number of core spectrum sharing tasks, such as opportunity detection, dynamic opportunity scheduling, and interference protection for the primary users, etc. This report proposes a Primary-Secondary Cooperation Framework to provide flexibility to all the involved parties in terms of choosing the level of cooperation that allow them to satisfy different objective priorities. The cooperation framework allows exchange of a probabilistic assurance: Spectrum Opportunity Duration Assurance (SODA) between the primary and secondary operations to improve the overall spectrum sharing experience for both the parties. This capability will give the spectrum sharing architectures new flexibility to handle evolutions in technologies, regulations, and the requirements of new bands being transitioned from fixed to share usage. In this dissertation we first look into the regulatory aspect of spectrum sharing. We analyze the Federal Communications Commission's (FCC) initiatives with regards to the commercial use of the 150 MHz spectrum block in the 3.5 GHz band. This analysis results into a Spectrum Access System (SAS) architecture and list of required functionalities. Then we address the nature of primary-secondary cooperation in spectrum sharing and propose to generate probabilistic assurances for spectrum opportunities. We use the generated assurance to observe the impact of cooperation from the perspective of spectrum sharing system management. We propose to incorporate primary user cooperation in the auctioning and resource allocation procedures to manage spectrum opportunities. We also analyze the improvement in spectrum sharing experience from the perspective of the primary and secondary users as a result of cooperation. We propose interference avoidance schemes that involve cooperation to improve the achievable quality of service. Primary-secondary cooperation has the potential to significantly influence the mechanism and outcomes of the spectrum sharing systems. Both the primary and secondary operations can benefit from cooperation in a sharing scenario. Based on the priorities of the primary and secondary operations, the users may decide on the level of cooperation that they are willing to participate. Also access to information about the availability and usability of the spectrum opportunity will result in efficient spectrum opportunity management and improved sharing performance for both the primary and secondary users. Thus offering assurances about the availability and duration of spectrum opportunity through primary-secondary cooperation will significantly improve the overall spectrum sharing experience. The research reported in this dissertation is expected to provide a fundamental analytical framework for characterizing and quantifying the implications of primary-secondary cooperation in a spectrum sharing context. It analyzes the technical challenges in modeling different level of cooperation and their impact on the spectrum sharing experience. We hope that this dissertation will establish the fundamentals of the spectrum sharing to allow the involved parties to participate in sharing mechanisms that is suitable to their objective priorities. / PHD

Nous étudions la réponse élastoplastique des verres silicatés à de fortes contraintes par diffusion Brillouin de la lumière. Des cartographies micro-Brillouin 3D du champ de densité résiduelle sont obtenues dans l'empreinte plastique laissée par une indentation Vickers et comparés à des modélisations par éléments finis. L'analyse conjointe des mesures réalisées en enclumes diamants sur la silice dans le domaine de déformation élastique et des données de la littérature fait apparaître que le durcissement anormal des modules élastiques avec la température est d'origine dynamique. La température à laquelle le durcissement est mis en évidence augmente avec la pression hydrostatique appliquée. Nous observons également que la densification progressive de la silice diminue fortement l'amplitude du maximum dans le frottement interne observé à 2 GPa de même qu'elle supprime l'anomalie dans la compressibilité. / We study the elastoplastic response of silicate glasses at high stresses with Brillouin light scattering. 3D micro-Brillouin mapping residual density field are obtained in the plastic region left by a Vickers indentation. Maps are compared with finite element modeling. The joint analysis of new high-pressure measurements in a diamond anvil cell on silica in the elastic domain and literature data revealed that the abnormal hardening of elastic moduli with temperature is of dynamical origin. The onset temperature of the hardening increases with increasing applied hydrostatic pressure. We also observe that densification of silica strongly reduces the amplitude of the maximum in internal friction observed at 2 GPa as well as it suppresses the compressibility anomaly.

O presente estudo teve como objetivo avaliar e comparar os processos de polpação sodaantraquinona e bissulfito base magnésio para Bambusa vulgaris Schrad. com 2 anos de idade oriundos de plantios comerciais no Maranhão Brasil visando a produção de polpa celulósica branqueável e não branqueável (números kappa 30±2 e 50±2 respectivamente). A matéria-prima foi caracterizada com relação à densidade básica, composição química e dimensões de fibras; para aos processos de polpação avaliou-se o tempo total de cozimento, o fator H, o rendimento bruto, rendimento depurado, teor de rejeitos, carga de reagentes químicos e propriedades físicomecânicas das polpas. Os resultados obtidos mostram que a matéria-prima apresentou valores típicos para a espécie em questão no que diz respeito à densidade básica, dimensões e índices morfológicos das fibras e composição química. Para o processo de polpação soda-antraquinona os níveis de deslignificação determinados (números kappa) foram obtidos com cargas alcalinas de 15 e 19% (base NaOH) respectivamente e fator H de 1218; para o processo bissulfito base magnésio as polpas celulósicas com os níveis de deslignificação estabelecidos foram obtidas com uma mesma carga de reagentes químicos 26% (base SO2) e fator H de 1218 para polpas com número kappa 30±2 e 828 para polpas com número kappa 50±2; o tempo total de cozimento para o processo soda-antraquinona necessário para obtenção das polpas celulósicas desejadas são, em média, 3,8 vezes menores aos do processo bissulfito base magnésio. Adicionalmente os rendimentos depurados foram 3,0 e 4,6 pontos porcentuais superiores para as polpas com números kappa 30±2 e 50±2 respectivamente no processo soda-antraquinona. Os ensaios físicomecânicos mostram as diferenças entre as polpas tanto no que diz respeito ao processo de polpação empregado quanto no nível de deslignificação, sendo este último um fator de diferenciação dos produtos (papel) que podem ser obtidos a partir das polpas celulósicas. Comparando-se os processos de polpação no que diz respeito às propriedades físico-mecânicas observa-se a superioridade das polpas soda-antraquinona exceto nos parâmetros de drenabilidade e densidade aparente. Os resultados obtidos neste trabalho mostram que para a produção de polpa celulósica a partir de Bambusa vulgaris o processo soda-antraquinona é superior ao processo bissulfito base magnésio tanto nos aspectos de engenharia de processo (quantitativos) como nos aspectos relacionados à qualidade da polpa obtida. / The present study had as objective evaluates and to compare the soda-antraquinone and magnesium base bisulfite pulping processes for Bambusa vulgaris Schrad. with 2 years old originating from commercial plantings in Maranhão Brazil seeking the production of bleachable and unbleachable cellulosic pulp grade\'s (kappa numbers 30±2 and 50±2 respectively). The raw material was characterized regarding the basic density, chemical composition and dimensions of fibers; for to the pulping processes was evaluated the total time of cooking, H factor, total yield, screened yield, rejects, load of chemical reagents and physicalmechanical properties of the pulps. The obtained results show that the raw material presented typical values for the species in subject in what says respect to the basic density, dimensions and morphologic indexes of the fibers and chemical composition. For the soda-antraquinone pulping process the certain levels of delignification (kappa numbers) were obtained with alkaline loads of 15 and 19% (NaOH base) respectively and a H factor of 1218; for the magnesium base bisulfite process the cellulosic pulps with the established levels of delignification were obtained with a fix load of chemical reagents 26% (SO2 base) and H factor of 1218 for pulps with kappa number 30±2 and 828 for pulps with kappa number 50±2; the necessary total time of cooking to the sodaantraquinone process to obtain the wanted cellulosic pulps are, on average, 3,82 time less when compared with the bisulfite process. Additionally the screened yields were 3 and 4,63 percent superior for the pulps with numbers kappa 30±2 and 50±2 respectively in the soda-antraquinone process. The physical-mechanical tests show the differences among the pulps in what says respect to the used pulping process as in the delignification level, being this last one a factor of differentiation of the products (paper) that can be obtained starting from the cellulosic pulps. Comparing the pulping processes as what concerns of physical-mechanical properties the superiority of the soda-antraquinone pulps is observed except in freeness and density parameters. The results obtained in this work show that for the production of cellulosic pulp from Bambusa vulgaris the soda-antraquinone process it is superior than the magnesium base bisulfite process as much in the aspects of engineering process (quantitative) as in the aspects related to the quality of the obtained pulp.

L’industrie chimique française est une industrie qui apparait alanguie au début du siècle et distancée par l’Allemagne. Elle connait cependant une croissance, plus lente, et un certain nombre de transformations notamment au point de vue de la recherche. Elle croît à l’ombre d’un système d’ententes généralisée et du dur labeur des ouvriers. Quand la guerre éclate en 1914, elle est mal préparée et doit effectuer une transformation rapide. Sa montée en puissance se fait grâce à un effort d’outillage et un développement du travail intensif où les travailleurs coloniaux paie un cher prix. Les approvisionnements anglais et américains sont essentiels pour sa production. La guerre terminée l’industrie chimique française doit se reconvertir. Elle pense, avec l’aide des pouvoirs publics, le faire grâce au Traité de Versailles. Cependant la crise de 1920-1921 montre les fragilités de cette industrie. Le retour à la croissance entre 1922 et 1929 s’accompagne à partir de 1925 d’une concurrence accrue de la part de l’Allemagne qui a rationnalisé ses structures. La croissance se fait principalement sur le marché national. En fin de période, la recherche scientifique commence à s’organiser au sein des entreprises. Toutefois la transformation capitalistique c’est imparfaitement faite. Le secteur reste dispersé et continue d’employer une forte main d’œuvre immigrée, seule capable d’accepter les tâches les plus dures. / The French Chemical industry appears in the beginning of the century as a backward industry compared with the german one. Indeed there is a slow growth and a a certain number of progress, in research for instance. The Chemical Industry is structured by a general system of cartels and harsh labour. At the outbreak of the War, the French Chemical industry is ill prepared and has to shift rapidly. It’s improvment is made through the basic development of traditionnal factories and an intensification of work due to colonial workforce for the most. At the end of the war, the chemical industry as to convert to civil markets. The 1920-1921 crisis shows the fragility of this industry. When the economic growth is back in 1922-29 the German chemical is more competitive thane ever having rationalized its structures. Thus the inner market is developped. At the end of the period, scientific research is rising. Nevertheless the capitalistic transformation is far for being made. The branch is still divided in archaïc (foreign workforce) and modern trends.

[pt] Neste trabalho se analisam as características de colapso de um solo laterítico submetido à percolação de um licor cáustico a diferentes concentrações. O solo é uma areia quartzosa com uma pequena fração de finos cauliníticos. O licor é um efluente industrial, resultante da produção de alumínio, a base de soda cáustica. Mediante o presente estudo, determinou-se o efeito da infiltração do licor cáustico sobre três aspetos: colapsividade, transporte de solutos e características de sucção. Isto foi feito através de um programa experimental que incluiu ensaios de caracterização física-química do solo e do licor, ensaios edométricos, em edômetros especiais, para avaliar as características de colapso e de transporte de solutos, e ensaios de sucção pelo método do papel filtro. Os resultados do programa experimental mostraram que o solo é colapsível em presença de água, sendo sua colapsividade aumentada em presença do licor cáustico. Também indicaram que os parâmetros de transporte e sucção são fortemente afetados pela percolação do licor. A mudança destes parâmetros é função da concentração do licor. / [en] In this work, characteristics of collapse of a laterítico soil submitted to percolation of a caustic liqueur to different concentrations are analysed. The soil comprises a quartzitic sand with a small fraction of kaolinitic clay. The liqueur is a caustic fluid, from an aluminium industry. In the present study, effects of the caustic liqueur infiltration were observed considering three aspects: collapse, solute transport and soil suction characteristics. This was done through an experimental program that included physical and chemical characterization of the soil and liqueur, special oedometer tests to evaluate simultaneously collapse characteristics and solute transport, and suction tests using the filter paper method. The results of the experimental program showed that the soil suffers volume change in presence of water, and its colapsivity is increased in presence of the caustic liqueur. They also indicated that the transport and suction parameters are affected strongly by the percolation of the liqueur.