With size down to nanoscale, nanomaterials exhibit novel properties exceeding or differing significantly from their bulk counterparts. In particular, amongst a wide range of interesting new nanostructures, tungsten based nanomaterials have demonstrated super physical, chemical, electronical and mechanical properties in a diverse range of applications which has been comprehensively reviewed. However, challenges still remain high on the effective processes to scale up the manufacturing of such nanomaterials, with desired shape, size and quality. These tungsten based nanomaterials are thus become the research subject of this project, and the study on continuous manufacturing of specifically inorganic fullerene WS2 (IF-WS2) nanoparticles, and their potential exploration as fillers to polymer matrix to fabricate nanocomposites with improved mechanical properties are the main objectives of this research. After a thorough assessment of the extremely promising potentials of tungsten based nanostructures, and review of the current bottleneck for large quantity production of IF-WS2, a generic experimental methodology and techniques used for the investigations have been described in experimental methodology part. In the following chapters, this thesis demonstrates the following research works: A novel rotary furnace for continuous scaling up manufacturing of IF-WS2 nanoparticles has been designed, constructed, tested and refined in this work. The new furnace consists of several key components: a tube furnace, self-contained rotary system, dynamic seal system, modified new tube with baffle, and a continuous gas-blow feeding system. Test results show that the rotary reactor has improved the lab scale manufacturing of IF-WS2 from sub-gram to several tens of grams per batch without agglomeration, which makes this technique a promising alternative for the replacement of the existing tall fluidised tower processing in industrial level production. As an important precursor for IF-WS2 nanomaterials production, the synthesis of WOx nanoparticles by high temperature thermal decomposition of Ammonium Paratungstate (APT) has been investigated, and the parameters have been optimised (with Ar flow at 6 L/min at 1350°C ) for achieving desired sizes. Further studies on the creation of uniform and ultra-thin WOx nanowires were carried out using solvothermal technique. The solvent concentrations, reaction time and solvent types have been systematically investigated, and the resulting WOx nanowires from tungsten chloride precursor in mixed cyclohexanol and ethanol solvent exhibited a record high specific surface area of 275 m2/g. This is fundamentally significant for their applications in sensor and electro-chromic devices. Reverse patterned growth of WOx nanorods was realised for the first time on an Au-coated W foil by a simple W-water vapour reaction. The resulting nanorods of different diameters, lengths and patterns have been created by tuning the growth parameters. Further nitriding under NH3 atmosphere at elevated temperature, converted the WOx nanorods, as a template, to WOxNy nanorods. The WOxNy nanorods have been found to inherit the patterns on the substrate and kept the size and shape of WOx nanorods. An interesting morphology revolution for the conversion of WOx to WOxNy nanorods was observed, and a mechanism has been proposed accordingly to account for the growth. This result represents a simple, innovative and efficient process for the reverse-patterned growth of new nanomaterials. Further development of the rotary furnace has led to a unique new class of core-shell composite nanoparticles, carbon (C)-coated IF-WS2 hollow nanoparticles, by continuous chemical vapour deposition (CVD) production. The composite nanoparticles exhibited a uniform and adjustable C coating, with little or no agglomeration. Importantly, the thermal stability of the core-shell C-coated IF-WS2 against oxidation in air has been improved by about 70°C, compared to the pristine IF-WS2. This new material could find applications where thermal stability is critical. Exploration of 0-4 wt% IF-WS2 as reinforcement in nylon 12 matrix nanocomposites has been carried out for the first time, using a combination of ultrasonic dispersion and magnetic stirring technique to achieve excellent IF-WS2 dispersion in the matrix. Tensile and bending test results showed moderate improvements of 27% and 28% respectively, with a 2 wt% IF-WS2 addition, but a staggering 185% and 148% improvement in toughness for the addition of 0.25 and 0.5 wt% IF-WS2 samples, against pure nylon 12, suggesting that such composites are promising candidates for structural and ballistic fibre applications.

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Medidas para controle de Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae) vem sendo buscadas intensamente nos últimos anos visto que este inseto é considerado a mais importante praga da citricultura devido a sua capacidade de transmitir as bactérias causadoras do Huanglongbing (HLB). Como não existem, ainda, medidas curativas para a doença, seu manejo se baseia, principalmente, no controle do vetor. O controle biológico com utilização do parasitoide Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) vem trazendo bons resultados em diversas partes do mundo. Para uma eficiente utilização deste inimigo natural, sua produção em larga escala é imprescindível, o que exige também a criação da praga. Assim, o objetivo deste trabalho foi estudar alguns pontos chaves da criação das duas espécies, visando aumentar seu rendimento, propor um sistema de produção em larga escala do parasitoide, estimando seu custo de implantação e manutenção e também avaliar o estabelecimento e eficiência do parasitoide liberado em diferentes regiões produtoras do estado de São Paulo. Visando a criação de D. citri, foram avaliados aspectos referentes ao tamanho das brotações do hospedeiro [Murraya paniculta (L.)] e viabilidade de uso de outro hospedeiro [Murraya koenigii (L.) Sprengel]. Para T. radiata foram investigados os efeitos da alimentação suplementar e um novo sistema de coleta de adultos. Foi ainda avaliada, em campo, a validade do modelo de exigências térmicas para as duas espécies. Utilizando-se os resultados obtidos, propôs-se um sistema de criação em larga escala do parasitoide, avaliando-se seu custo de implantação e manutenção. Foram realizadas liberações do parasitoide em diferentes regiões, do estado de São Paulo, ao longo de um ano, para avaliar seu estabelecimento e parasitismo. Verificou-se que brotações de M. paniculata com comprimento entre 1,0 a 2,6 cm favorecem a oviposição, e aquelas com tamanho médio de 4,3 são melhores para alimentação. A viabilidade de ovos, de ninfas e total, e a duração da fase de ovo de D. citri não foram afetadas pelos hospedeiros, M. paniculata e M. koenigii; por outro lado, as durações da fase ninfal e total foram maiores em M. paniculata, para qual D. citri apresenta preferência quando em teste com chance de escolha, não tendo sido verificada diferença em teste sem chance de escolha. A umidade afeta a emergência de T. radiata no sistema de coleta proposto e tal sistema permite uma economia de tempo na coleta de parasitoides de até cinco vezes. O fornecimento de alimento para adultos de T. radiata não afetou sua longevidade, nem sua capacidade de parasitismo. Os modelos de exigências térmicas estimados para D. citri e T. radiata, são válidos para temperaturas mais elevadas. Recomenda-se o uso de mudas de M. paniculata apenas duas vezes na criação de D. citri. O maior custo do sistema é devido à produção de ninfas de T. radiata e à mão de obra. T. radiata se estabeleceu em todas regiões testadas com boas taxa de redução de ninfas. O parasitismo médio foi inicialmente alto tornando-se variável e foi afetado pela estação do ano. / Control methods for Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae) have been intensively researched in recent years, since this insect is considered the most important citrus pest due to its ability to transmit the Huanglongbing (HLB) bacterium. Because no remedy for the disease is yet available, its management is based principally on control of the vector. Biological control using the parasitoid Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) is providing excellent results in many parts of the world. For efficient utilization of this natural enemy, large-scale production is necessary, which also requires rearing the pest. This study examined some key aspects of rearing these two species, in order to increase their productivity; propose a large-scale production system for the parasitoid, estimating the costs of its implantation and management; and also to evaluate the establishment and efficiency of the parasitoid, released in different citrus-producing areas of São Paulo state. Aspects of rearing D. citri related to the branch size of the host [Murraya paniculata (L.)] and the feasibility of using an alternative host [Murraya koenigii (L.) Sprengel] were evaluated. For T. radiata, the effects of supplementary feeding and a new system for collecting adults were investigated. The validity of the thermal-requirements model was evaluated in field conditions for both species. Based on the results obtained, a large-scale rearing system for the parasitoid is proposed, together with an evaluation of its implantation and management costs. Parasitoid releases were conducted, and its performance in different climate zones during one year was evaluated in order to assess its establishment and parasitism efficiency. The results indicated that M. paniculata buds sized 1.0 to 2.6 cm are best for egg laying, and buds averaging 4.3 cm are better for feeding. The egg, nymph and total viabilities, and the egg-stage duration of D. citri were not affected by the different hosts M. paniculata and M. koenigii; however, the nymphal stage and the total development duration were longer on M. paniculata, for which D. citri showed a preference in the free-choice test. No difference was seen in the no-choice test. The humidity affects the emergence of T. radiata in the proposed collection system. This system reduces the time required to produce the parasitoid by up to five-fold. The food supply for adults of T. radiata did not affect the longevity or parasitism capacity. The estimated thermal-requirement models for D. citri and T. radiata are valid at higher temperatures. M. paniculata seedlings should be used only twice in rearing D. citri. The highest cost in the rearing system is due to the production of T. radiata nymphs and to labor. T. radiata established successfully in all zones tested, with good rates of nymph reduction. The mean parasitism incidence was initially high and then became variable, and was affected by the season of the year.

Cette thèse porte sur la conceptualisation de la résilience au sein du réseau logistique. La résilience a été initialement définie comme la capacité du métal à rebondir et à revenir à l'état initial face à un choc. Nous avons essayé de transposer et d'appliquer cette notion dans le réseau logistique, qui est confronté inévitablement à des aléas et subit souvent des ruptures. Après une étude conceptuelle multidisciplinaire de la résilience, nous avons tenté de définir la capacité de résilience au sein du réseau logistique dans une perspective de la Resource Based View. Selon nous, la résilience est constituée par trois caractéristiques formant un processus rétroactif: absorption, réponse et capitalisation. Une série de mécanismes qui favorisent la résilience a été identifiée à partir d'une revue de la littérature. Notre étude exploratoire prend appui sur le contexte de la production à grande échelle des produits assemblés en Chine, par une recherche empirique de vingt-deux entreprises internationales. A cette fin, nous avons réalisé des enquêtes avec des industriels et deux études de cas dans le secteur automobile et dans le secteur électronique grand public. Sur le terrain, nous avons confirmé et complété la signification de la résilience, synthétisé un processus de son fonctionnement, identifié les mécanismes qui favorisent cette capacité, les facteurs influençant sa formation et ses avantages compétitifs stratégiques. / This PhD dissertation works on the conceptualization of resilience of supply chain network. The initial definition of resilience is the quality of metal of rebounding and returning to its original shape after bending. Our study tries to transpose and apply this concept into the supply chain network, which confronts inevitably with accidents and suffers disruptions. Based on multidisciplinary literature, we have tried to develop a definition of the resilience capacity of supply chain network in the perspective of Resource Based View. In our opinion, the resilience comprises three characteristics, which form a retroactive process, absorption, response, and capitalization. We have synthesized a set of mechanisms, which are favorable for the improvement of resilience. Our exploratory and empirical study is implemented in the field of large scale production of assembling products in China, data gathered by twenty two international companies. We have carried out survey and two case studies in automotive and consumer electronics industries. By the field study, we have validated and complemented the signification of resilience, synthesized its implementation process, identified the enhancing mechanisms, and indicated the influential factors and strategic competitive advantages.

Medidas para controle de Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae) vem sendo buscadas intensamente nos últimos anos visto que este inseto é considerado a mais importante praga da citricultura devido a sua capacidade de transmitir as bactérias causadoras do Huanglongbing (HLB). Como não existem, ainda, medidas curativas para a doença, seu manejo se baseia, principalmente, no controle do vetor. O controle biológico com utilização do parasitoide Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) vem trazendo bons resultados em diversas partes do mundo. Para uma eficiente utilização deste inimigo natural, sua produção em larga escala é imprescindível, o que exige também a criação da praga. Assim, o objetivo deste trabalho foi estudar alguns pontos chaves da criação das duas espécies, visando aumentar seu rendimento, propor um sistema de produção em larga escala do parasitoide, estimando seu custo de implantação e manutenção e também avaliar o estabelecimento e eficiência do parasitoide liberado em diferentes regiões produtoras do estado de São Paulo. Visando a criação de D. citri, foram avaliados aspectos referentes ao tamanho das brotações do hospedeiro [Murraya paniculta (L.)] e viabilidade de uso de outro hospedeiro [Murraya koenigii (L.) Sprengel]. Para T. radiata foram investigados os efeitos da alimentação suplementar e um novo sistema de coleta de adultos. Foi ainda avaliada, em campo, a validade do modelo de exigências térmicas para as duas espécies. Utilizando-se os resultados obtidos, propôs-se um sistema de criação em larga escala do parasitoide, avaliando-se seu custo de implantação e manutenção. Foram realizadas liberações do parasitoide em diferentes regiões, do estado de São Paulo, ao longo de um ano, para avaliar seu estabelecimento e parasitismo. Verificou-se que brotações de M. paniculata com comprimento entre 1,0 a 2,6 cm favorecem a oviposição, e aquelas com tamanho médio de 4,3 são melhores para alimentação. A viabilidade de ovos, de ninfas e total, e a duração da fase de ovo de D. citri não foram afetadas pelos hospedeiros, M. paniculata e M. koenigii; por outro lado, as durações da fase ninfal e total foram maiores em M. paniculata, para qual D. citri apresenta preferência quando em teste com chance de escolha, não tendo sido verificada diferença em teste sem chance de escolha. A umidade afeta a emergência de T. radiata no sistema de coleta proposto e tal sistema permite uma economia de tempo na coleta de parasitoides de até cinco vezes. O fornecimento de alimento para adultos de T. radiata não afetou sua longevidade, nem sua capacidade de parasitismo. Os modelos de exigências térmicas estimados para D. citri e T. radiata, são válidos para temperaturas mais elevadas. Recomenda-se o uso de mudas de M. paniculata apenas duas vezes na criação de D. citri. O maior custo do sistema é devido à produção de ninfas de T. radiata e à mão de obra. T. radiata se estabeleceu em todas regiões testadas com boas taxa de redução de ninfas. O parasitismo médio foi inicialmente alto tornando-se variável e foi afetado pela estação do ano. / Control methods for Diaphorina citri Kuwayama, 1908 (Hemiptera: Liviidae) have been intensively researched in recent years, since this insect is considered the most important citrus pest due to its ability to transmit the Huanglongbing (HLB) bacterium. Because no remedy for the disease is yet available, its management is based principally on control of the vector. Biological control using the parasitoid Tamarixia radiata (Waterston, 1922) (Hymenoptera: Eulophidae) is providing excellent results in many parts of the world. For efficient utilization of this natural enemy, large-scale production is necessary, which also requires rearing the pest. This study examined some key aspects of rearing these two species, in order to increase their productivity; propose a large-scale production system for the parasitoid, estimating the costs of its implantation and management; and also to evaluate the establishment and efficiency of the parasitoid, released in different citrus-producing areas of São Paulo state. Aspects of rearing D. citri related to the branch size of the host [Murraya paniculata (L.)] and the feasibility of using an alternative host [Murraya koenigii (L.) Sprengel] were evaluated. For T. radiata, the effects of supplementary feeding and a new system for collecting adults were investigated. The validity of the thermal-requirements model was evaluated in field conditions for both species. Based on the results obtained, a large-scale rearing system for the parasitoid is proposed, together with an evaluation of its implantation and management costs. Parasitoid releases were conducted, and its performance in different climate zones during one year was evaluated in order to assess its establishment and parasitism efficiency. The results indicated that M. paniculata buds sized 1.0 to 2.6 cm are best for egg laying, and buds averaging 4.3 cm are better for feeding. The egg, nymph and total viabilities, and the egg-stage duration of D. citri were not affected by the different hosts M. paniculata and M. koenigii; however, the nymphal stage and the total development duration were longer on M. paniculata, for which D. citri showed a preference in the free-choice test. No difference was seen in the no-choice test. The humidity affects the emergence of T. radiata in the proposed collection system. This system reduces the time required to produce the parasitoid by up to five-fold. The food supply for adults of T. radiata did not affect the longevity or parasitism capacity. The estimated thermal-requirement models for D. citri and T. radiata are valid at higher temperatures. M. paniculata seedlings should be used only twice in rearing D. citri. The highest cost in the rearing system is due to the production of T. radiata nymphs and to labor. T. radiata established successfully in all zones tested, with good rates of nymph reduction. The mean parasitism incidence was initially high and then became variable, and was affected by the season of the year.

Considering the long term target set by the Swedish government of having an energy system basedexclusively on renewable sources, the potential for different renewable sources need to beinvestigated. When analyzing the sources used for electricity production in Sweden today, solarPV represents a very small share. This relatively small share also mainly consists of grid-connecteddistributed PV systems, and to analyze the possibilities of making solar energy a larger share inthe electricity production in Sweden this study will focus on grid-connected centralized PV farms.The main purpose of the study is to identify the potential for grid-connected centralized PVsystems for large scale production in Sweden. This will include an identification of the mostimportant key factors influencing the profitability, an investment calculation to be aware of theprofitability, a prediction of the future development of the PV industry in Sweden and lastly themain challenges that the PV industry is facing.To conduct this study a collaboration with Vattenfall Vind AB has been made, where a case studybased on three specific locations has been implemented when analyzing both the profitability andthe key factors. These three cases are based on places where Vattenfall has existing wind farms orhas assigned for upcoming ones. These areas could be seen as a potential benefit since the companyalready has started to inspect the land area, and that wind and PV farms might be able to sharenecessities such as infrastructure.The results of the study mainly indicate that the PV industry most likely will continue develop andgrow, but the profitability of investing in grid-connected centralized PV farms does not lookpromising today or in the next coming years. This mainly due to low prices for electricity anduncertainties in the future development of the financial support policy. The location is also veryimportant for this type of installation. There are places in southern Sweden with enough insolation,but these areas can be seen as limited. To make solar energy a larger share of the electricityproduction in Sweden in a profitable way today, more investments should be made in gridconnecteddistributed PV systems rather than grid-connected centralized PV farms. PV farms forlarge scale production might though be more profitable in the future when the prices for modulesand inverters will decrease further and when the spot price increases.