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We describe a laser-plasma platform for photon-photon collision experiments to measure fundamental quantum electrodynamic processes such as the linear Breit-Wheeler process with real photons. The platform has been developed using the Gemini laser facility at the Rutherford Appleton Laboratory. A laser wakefield accelerator and a bremsstrahlung convertor are used to generate a collimated beam of photons with energies of hundreds of MeV, that collide with keV x-ray photons generated by a laser heated plasma target. To detect the pairs generated by the photon-photon collisions, a magnetic transport system has been developed which directs the pairs onto scintillation-based and hybrid silicon pixel single particle detectors. We present commissioning results from an experimental campaign using this laser-plasma platform for photon-photon physics, demonstrating successful generation of both photon sources, characterisation of the magnetic transport system and calibration of the single particle detectors, and discuss the feasibility of this platform for the observation of the Breit-Wheeler process. The design of the platform will also serve as the basis for the investigation of strong-field quantum electrodynamic processes such as the nonlinear Breit-Wheeler and the Trident process, or eventually, photon-photon scattering. We describe a laser–plasma platform for photon–photon collision experiments to measure fundamental quantum electrodynamic processes. As an example we describe using this platform to attempt to observe the linear Breit–Wheeler process. The platform has been developed using the Gemini laser facility at the Rutherford Appleton Laboratory. A laser Wakefield accelerator and a bremsstrahlung convertor are used to generate a collimated beam of photons with energies of hundreds of MeV, that collide with keV x-ray photons generated by a laser heated plasma target. To detect the pairs generated by the photon–photon collisions, a magnetic transport system has been developed which directs the pairs onto scintillation-based and hybrid silicon pixel single particle detectors (SPDs). We present commissioning results from an experimental campaign using this laser–plasma platform for photon–photon physics, demonstrating successful generation of both photon sources, characterisation of the magnetic transport system and calibration of the SPDs, and discuss the feasibility of this platform for the observation of the Breit–Wheeler process. The design of the platform will also serve as the basis for the investigation of strong-field quantum electrodynamic processes such as the nonlinear Breit–Wheeler and the Trident process, or eventually, photon–photon scattering.

International audience; The hemp plant Cannabis sativa Linn, referring to industrial hemp, is a high-yielding annual industrial crop grown providing fibers from hemp stalk and oil from hemp seeds. Although hemp is a niche crop, hemp production is currently undergoing a renaissance. More than 30 countries grow hemp, with China being the largest hemp producing and exporting country. Europe and Canada are also important actors in the global hemp market. Traditionally, hemp as a fiber plant has been used for the production of apparels, fabrics, papers, cordages and building materials. The hurds, as waste by-product of fiber production, were used for bedding of animals, the seeds for human nutrition, e.g., as flour, and the oil for a wide range of purposes, from cooking to cosmetics. Hemp has also been an important crop throughout human history for medicine. Other more recent applications include materials for insulation and furniture, automotive composites for interior applications and motor vehicle parts, bioplastics, jewelry and fashion sectors, animal feed, animal bedding, and energy and fuel production. Foods containing hemp seed and oil are currently marketed worldwide for both animal and human nutrition. They also find applications in beverages and in neutraceutical products. Hemp oil is also used for cosmetics and personal care items, paints, printing inks, detergents and solvents. It is estimated that the global market for hemp consists of more than 25,000 products. Currently, the construction and insulation sector, paper and textile industries, and food and nutrition domains are the main markets while the cosmetics and automotive sector are growing markets. Innovative applications, e.g., in the medical and therapeutic domains, cosmeceuticals, phytoremediation, acoustic domain, wastewater treatment, biofuels, biopesticides and biotechnology, open new challenges. Hemp is also the object of numerous fundamental studies. This review presents and discusses the traditional and new uses of industrial hemp.

Microbial biophotovoltaic cells exploit the ability of cyanobacteria and microalgae to convert light energy into electrical current using water as the source of electrons. Such bioelectrochemical systems have a clear advantage over more conventional microbial fuel cells which require the input of organic carbon for microbial growth. However, innovative approaches are needed to address scale-up issues associated with the fabrication of the inorganic (electrodes) and biological (microbe) parts of the biophotovoltaic device. Here we demonstrate the feasibility of using a simple commercial inkjet printer to fabricate a thin-film paper-based biophotovoltaic cell consisting of a layer of cyanobacterial cells on top of a carbon nanotube conducting surface. We show that these printed cyanobacteria are capable of generating a sustained electrical current both in the dark (as a ‘solar bio-battery’) and in response to light (as a ‘bio-solar-panel’) with potential applications in low-power devices., Cyanobacteria can be exploited to convert light energy into electrical current, however utilising them efficiently for power generation is a challenge. Here, the authors use a simple commercial inkjet printer to fabricate a thin-film paper-based biophotovoltaic cell capable of driving low-power devices.

Some Parties (Countries) to the UNFCCC decided to include the carbon uptake by harvested wood products (HWP) in a new general accounting framework after 2012 (post Kyoto). The analysis aims to make a comparison between the cascaded use of HWP and the use of wood for energy. We combine the new HWP framework with an assumed increased 50 million m3harvest level in Canada and evaluate the impact of the GHG emissions over a 100-year period. Our reference case assumes all harvested wood is an immediate CO2emission (IPCC default) and no substitution effects, i.e. annual GHG emissions of 41 million tonnes CO2eq. In our wood utilization scenario's, harvested trees are allocated (in varying shares) to three end-products: construction wood, paper products and pellets for power production. In comparison with our base case, a combination of fossil fuel substitution, material substitution and temporary carbon uptake by HWP leads to significant decreases in GHG emissions. All scenario's show annual GHG emission between 18 and 21 million tonnes CO2eqexcept for triple use without recycling (at least 24 million tonnes CO2eq). We conclude that GHG emissions of our scenarios are substantially lower than IPCC default. However, it is difficult to incorporate one single method to account for GHG uptake and emissions by HWP, due to end use efficiency and recycling options. Further GHG allocation over individual countries is not straightforward and needs further research. © 2013 Elsevier Ltd.

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A loss of industrial competitiveness is a major concern for energy and environmental policy design. This thesis studies the impacts of energy prices and environmental regulation asymmetries among countries on the competitiveness of the manufacturing industry in Europe and in the World. First, main factors of competitiveness in two energy-intensive industries, steel and paper sectors, are identified with econometric methods. The role of energy is then quantified and weighted relatively to these other factors. In particular, the evolution of exports and production for a national industry, as well as changes in production capacities of a factory, are analysed. Secondly, high energy prices, or a new environmental regulation, do not impact only energy-intensive industries but also downstream manufacturing sectors. The scale of the research is therefore extended to the whole manufacturing industry on a global scope. The objective is to grasp energy interdependencies between industrial sectors all along the production chain, including national differences in energy use. The study is based on a matrix calculation method using Input-Output tables. Energy dependence of national industries is not only a domestic issue, but also an international one.; La crainte d'une perte de compétitivité industrielle est au cœur des débats sur de nouvelles politiques énergétiques et environnementales. Cette thèse étudie les effets d'une asymétrie des prix de l'énergie et des régulations environnementales entre pays sur la compétitivité de l'industrie manufacturière en Europe et dans le Monde. Dans un premier temps, les principaux déterminants de la compétitivité de deux industries grandes consommatrices d'énergie, la sidérurgie et l'industrie du papier, sont identifiés par des méthodes économétriques. Le rôle de l'énergie est ensuite quantifié et pondéré par rapport à ces déterminants. Notamment, l'évolution des exportations et de la production d'une industrie nationale ainsi que les changements de capacité des sites de production sont analysés. Dans un second temps, une hausse des prix de l'énergie, ou l'instauration d'une contrainte environnementale, n'affecte pas uniquement les secteurs grands consommateurs d'énergie mais aussi les industries en aval de la chaîne de production industrielle. L'échelle de l'étude est alors étendue à toute l'industrie manufacturière sur un périmètre mondial. L'objectif est d'appréhender les interdépendances énergétiques des secteurs industriels, en incluant les différences nationales et sectorielles, au travers d'une étude matricielle sur les tableaux entrées-sorties. La dépendance de l'industrie aux prix de l'énergie, et donc sa compétitivité, n'est pas seulement un enjeu national, mais une problématique européenne, voire mondiale.

A loss of industrial competitiveness is a major concern for energy and environmental policy design. This thesis studies the impacts of energy prices and environmental regulation asymmetries among countries on the competitiveness of the manufacturing industry in Europe and in the World. First, main factors of competitiveness in two energy-intensive industries, steel and paper sectors, are identified with econometric methods. The role of energy is then quantified and weighted relatively to these other factors. In particular, the evolution of exports and production for a national industry, as well as changes in production capacities of a factory, are analysed. Secondly, high energy prices, or a new environmental regulation, do not impact only energy-intensive industries but also downstream manufacturing sectors. The scale of the research is therefore extended to the whole manufacturing industry on a global scope. The objective is to grasp energy interdependencies between industrial sectors all along the production chain, including national differences in energy use. The study is based on a matrix calculation method using Input-Output tables. Energy dependence of national industries is not only a domestic issue, but also an international one.; La crainte d'une perte de compétitivité industrielle est au cœur des débats sur de nouvelles politiques énergétiques et environnementales. Cette thèse étudie les effets d'une asymétrie des prix de l'énergie et des régulations environnementales entre pays sur la compétitivité de l'industrie manufacturière en Europe et dans le Monde. Dans un premier temps, les principaux déterminants de la compétitivité de deux industries grandes consommatrices d'énergie, la sidérurgie et l'industrie du papier, sont identifiés par des méthodes économétriques. Le rôle de l'énergie est ensuite quantifié et pondéré par rapport à ces déterminants. Notamment, l'évolution des exportations et de la production d'une industrie nationale ainsi que les changements de capacité des sites de production sont analysés. Dans un second temps, une hausse des prix de l'énergie, ou l'instauration d'une contrainte environnementale, n'affecte pas uniquement les secteurs grands consommateurs d'énergie mais aussi les industries en aval de la chaîne de production industrielle. L'échelle de l'étude est alors étendue à toute l'industrie manufacturière sur un périmètre mondial. L'objectif est d'appréhender les interdépendances énergétiques des secteurs industriels, en incluant les différences nationales et sectorielles, au travers d'une étude matricielle sur les tableaux entrées-sorties. La dépendance de l'industrie aux prix de l'énergie, et donc sa compétitivité, n'est pas seulement un enjeu national, mais une problématique européenne, voire mondiale.

Foram estudadas as características anatômicas da madeira de 7 espécies ocorrentes na floresta Amazônia com vistas a geração de energia ou produção de papel. Para qualificação de madeira para produção de papel consideraram-se, dentre outros parâmetros, o coeficiente de rigidez e de flexibilidade, densidade, índice de Runkel, percentual de fibras, vasos, parênquimaaxial e de raios. Para produção de energia determinaram-se a densidade, a fração parede (%) das células em relação a área ocupada por cada tipo de células, percentual de fibras, de vasos e de parênquima axial e radial. O estudo foi baseado em 3 áreas de seções transversais, orientadas do centro em direção ao alburno. Com base nas características anatômicas e na densidade, Bellucia grossularioides, Cecropia palmata, Duguetia cauliflora, Eschweilera matamata e Parkia multuijuga podem ser usadas para polpa destinada a produção de papel, e Myrocarpus frondosus, Sloaneagrandis podem ser usadas na produção de carvão. _________________________________________________________________________________ ABSTRACT The wood anatomy of 7 species from the Brazilian Amazon forest was studied to evaluate them for energy production (charcoal and alcohol) and for paper production. Trans-verse. For paper production, the wood was qualified according to the coefficient of rigidity and flexibility, density, Runkel index, the percent of fibers, vessel, axial parenchyma and percent of area occupied by rays. For energy production, wall fraction in relation to the area occupied bycells (%), percent of fibers, vessel, and both axial and ray parenchyma, as well as wall density were considered. The study was based on 3 areas of the cross section of the trunk, from the center towards the sapwood. On the basis of anatomy and density, Bellucia grossularioides, Cecropia palmata, Duguetia cauliflora, Eschweilera matamata and Parkia multijuga can be used for pulp for paper production, and Myrocarpus frondosus, Sloanea grandis can be used for charcoal production.