Carbon fibre reinforced polymers (CFRP) are used in increasing quantities as they have some 2 of the best properties in terms of specific strength and stiffness of any widely available material. By 2020, annual global CFRP production is expected to be over 140,000 tonnes. 4However, the resulting increased quantity of CFRP waste has highlighted the need for 5 sustainable treatment options as carbon fibre manufacture has high-energy intensity. A life 6 cycle methodology is used to evaluate primary energy demand (PED) and global warming 7 potential (GWP) leveraging best available literature data, process models, and experimental 8 work. Overall results indicate that recycling scenarios are generally the environmentally 9 preferable options over landfill and incineration. However, the relative environmental 10 benefits of advanced recycling processes (i.e., pyrolysis, fluidised bed, and chemical 11 recycling process) depend on the method used to determine displacement of virgin carbon 12 fibre by recycled carbon fibre. Totally, recycling processes can achieve a representative GWP 13 of -19 to -27 kg CO 2 eq. and PED of -395 to -520 MJ per kg CFRP, providing superior 14 environmental performance to conventional composite waste treatment technologies.

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Abstract-More-electric aircraft (MEA) has become a dominant trend for modern aircraft. On-board MEA, many functions, which are conventionally driven by pneumatic and hydraulic power, are replaced with electrical subsystems. Starting aircraft engines with an electrical motor instead of using pneumatic power from the auxiliary power unit (APU) is one of the major characteristics of future aircraft. This paper presents the development of a novel electric starter-generator system for aircraft applications. The paper describes the main achievements of the project within the key areas including electric machines, power electronic converters, thermal management and overall system control design. The developed prototype has been tested successfully and the test results are presented in this paper.

The microstructure of transition aluminas obtained via the dehydration of boehmite has been characterized by using transmission electron microscopy (TEM). The presence of ␥-, ␦-, and -aluminas was identified by using selected-area electron diffraction. Modifications that resulted from the reordering of aluminum vacancies on octahedral sites in a cubic close-packed oxygen network have been detected and analyzed by using high-resolution transmission electron microscopy (HRTEM) combined with image simulations. A good correspondence of the observed and calculated images confirmed the ordering of vacant octahedral sites located on {011} and {011} planes that formed a zigzag configuration along the 〈010〉 direction. Two more arrangements of empty octahedral sites, but now concentrated on {001} planes, have been determined in the sintered powder-gel agglomerates. Structure analysis suggested that the modifications are all associated with the rearrangement of vacant sites during the phase transformation from ␥-alumina to ␦-alumina, and further to -alumina, and may be driven by configuration entropy minimization.

The chemical route with thermal reduction is found to be the least impacting route after a comparative LCA of three main graphene production routes.

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