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Companies are facing a rapidly changing and ever more challenging environment. Globalization, together with a shifting political landscape, is combining with major transformations in population, urbanization, resource utilization, climate change and consumer attitudes. Through the evolution of communications networks there is growing connectivity that with the rise of non-governmental organizations (NGOs) results in an increasingly transparent society. Socially responsible investors combining forces with the media and NGOs have emerged as a major force compelling firms through the capital markets toward a more environment friendly behaviour. The global food industry is especially susceptible to climate change and shifting consumer attitudes and thus has to increasingly respond to external stakeholders in order to remain competitive. How did attitudes and perceptions change in recent years toward the industries environmental performance and how did this influence their financial results? Our research investigates forty-six global food industry companies.

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The development of high performance insulating materials incorporating nanotechnologies has enabled considerable decrease in the effective thermal conductivity. Besides the use of conventional insulating materials, such as mineral fibers, the adoption of new nano-technological materials such as aerogel, vacuum insulation panels, graphite expanded polystyrene, is growing. In order to reduce the thermal conductivity of polystyrene insulation materials, during the manufacturing, nano/micro-sized graphite particles are added to the melt of the polystyrene grains. The mixing of graphite flakes into the polystyrene mould further reduces the lambda value, since graphite parts significantly reflect the radiant part of the thermal energy. In this study, laboratory tests carried out on graphite insulation materials are presented. Firstly, thermal conductivity results are described, and then sorption kinetic curves at high moisture content levels are shown. The moisture up-taking behaviour of the materials was investigated with a climatic chamber where the relative humidity was 90% at 293 K temperature. Finally, calorific values of the samples are presented after combusting in a bomb calorimeter.

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Authors: I. Tamáska, Z. Vértesy, A. Deák, P. Petrik, K. Kertész, and László Biró

Bioinspired 1+2D nanoarchitectures inspired by the quasi-ordered structures occurring in photonic nano-architectures of biological origin, like for example butterfly scales, were produced by depositing a layer of SiO2 nanospheres (156 nm and 292 nm in diameter) on Si wafers, over which a regular multilayer composed from three alternating layers of SiO2 and TiO2 was deposited by physical vapor deposition. Flat multilayers were deposited in the same run on oxidized Si (324 nm SiO2 thickness) for comparison. Different types of disorder (in plane and out of plane) were purposefully allowed in the 1+2D nanoarchitectures. The positions of the specular reflection maxima for the flat multilayer and for the two different bioinspired nanoarchitectures were found to be similar. Additionally to this, the bioinspired nanoarchitectures exhibited angle independent diffuse reflection too, which was absent in the flat multilayer. Different model calculations were made to explain the specular and diffuse optical properties of the samples. Satisfactory agreement was obtained between experimental data and model calculations.

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Acta Alimentaria
Authors: Zs. Albert, Zs. Erős-Honti, G. Solymossy, L. Kuznyák, A. Miskó, Cs. Deák, M. Ladányi, I. Terbe, and I. Papp

In this study two widely consumed Hungarian bell pepper cultivars ‘Hó’ and ‘Kárpia’, were examined. Aims of the investigations were to describe the postharvest behaviour of the cultivars and assign associated traits to the largely different shelf-life that is well known for these cultivars. ‘Hó’ is a white fruit flesh cultivar with average postharvest storability, while ‘Kárpia’ is of Capia type, with extended shelf-life. Postharvest water loss rates were measured, and differences between the cultivars were found. Interestingly, however, the longer shelf-life ‘Kárpia’ fruits showed higher water loss rate. Bright field microscopy was used to study the tissue structure of the outer pericarp of pepper fruits to find explanation for the good storability of ‘Kárpia’. Significantly more cell layers of the hypodermal collenchyma were found in ‘Kárpia’, than in ‘Hó’. Thicker cell walls were also found in this tissue but also in the epidermis. Fluorescent imaging confirmed these observations and also supported differences in the cuticular thickness between the cultivars. Our results highlight epidermal and hypodermal tissue structures as potential factors to influence the shelf-life of bell pepper fruits.

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