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Public transport systems in different parts of the world are currently undergoing a change characterised by the introduction of battery-powered electric buses in everyday operations. The introduction of electric buses brings new challenges such as high investment costs and technology concerns, as well as new forms of collaboration between both established and new actors. The aim of this paper is to disentangle different actors’ rationale for the transition, identifying underlying interests in and expectations of the electric bus system. With a focus on the Swedish context, we found that whilst common rationales exist, these are influenced by collective expectations and different underlying interests for the actor groups. We found that the interests of the actors are grounded in expectations of future developments, but also relate to the experience that the transition is occurring faster than previously anticipated. The results show a high degree of consensus regarding the transition to electric buses, although the actors have varying resources and action spaces with which to influence the transition, which is largely determined by the institutional and local context.

Adsorption refrigeration, as a renewable cooling method, has received more attention in the last few years. The interest in this technology comes especially from developing and tropical countries, where the demand for cooling increases every year due to economy and population growth. Based on this scenario, this work aims to develop a numerical model of an adsorption chiller driven with solar energy, which can be used to optimize the cooling system operation of the building where the device is situated and compare it with the current cooling methods in use. The numerical study here presented was created using Matlab/Simulink™, it is based on a lumped parameter model that relies on physical properties and represents a cooling system using a pair of silica gel-water in a two-bed chiller. In this study, the authors proposed a simplified version of the system and the numerical model, which aims to reduce the simulation time and provide faster results. Besides the temperatures in the system, which range from 52 °C to 72 °C in the hot cycle and 12 °C to 23 °C in the chilled water cycle, the results also include the variation of water uptake in the two adsorbent beds. In general, the simulated temperature, cooling and heating power and coefficient of performance (COP) are in fair agreement with the literature data, nevertheless, the final results show that improvements still have to be performed.

Parameters of environmental health, including paracellular permeability of external epithelia, functional state of lysosomes and the level of metallothioneins (MTs), were examined using fluorescent markers and vital microfluorometry in different tissues of the marine gastropod, Hexaplex trunculus, from a coal-polluted and coal-free site. Vital microfluorometrical examinations exhibited enhanced paracellular permeability of external epithelia to the anionic marker, fluorescein (FLU), lower lysosomal accumulation of neutral red (NR) as well as higher levels of MTs, when compared with epithelia of gastropods from the coal-free site. Those differences were particularly marked in the foot epithelium, which is in direct contact with the substrate. In addition, cadmium was measured by ICP-AES in the hepatopancreas of gastropods sampled from the coal-polluted site and two coal-free sites. Significantly higher levels of Cd were found in gastropod hepatopancreas from the coal-polluted site. In addition, two months feeding experiments conducted in aquaria containing: (a) coal pieces covered by barnacles; (b) natural rocks covered by barnacles; and (c) natural rocks with barnacles + bare coal pieces, demonstrated significant increase of Cd concentration in the hepatopancreas of the gastropods exposed to coal. We suggest that coal in the marine environment has detrimental effects on marine gastropods, both directly through contact with the organisms and indirectly through the food web.

This paper is devoted to study the electrochemical behavior of Pt catalyst in a polymer electrolyte fuel cell at various operating conditions and at different electric potential difference (also known as voltage) cycling applied in accelerated stress tests. The degradation of platinum is considered with respect to the Pt ion dissolution and the Pt oxide coverage of catalyst described by a one-dimensional model. In the model, degradation rate increases with temperature and decreasing particle diameter of Pt nano-particles. The theoretical study of the underlying diffusion system with the nonlinear reactions is presented by analytical methods and gives explicit solutions through a first integral of the ODE system. Numerical tests are obtained using a second order implicit-explicit scheme. The computer simulation shows that the lifetime of the catalyst depends on the voltage profile and the upper potential level. By this Pt mass loss is more significant at the membrane surface than at the gas diffusion layer.

Ziel der Diplomarbeit ist es, sich kritisch mit dem Thema Sanierung im Bestand und der Revitalisierung der Plattenbausiedlungen in den neuen Europ��ischen L��ndern, auseinanderzusetzen. Dies ist wichtig, weil das Sanierungsproblem nicht nur im Mittelosteurop��ischen Raum (MOE) gegenw��rtig ist, sondern auch in vielen westeurop��ischen Industriel��ndern ein zentrales Thema geworden ist. Im Zuge der Ausarbeitung wird in Bezug auf Deutschland ein geschichtlicher R��ckblick gemacht warum diese Siedlungen entstanden, wie viele Plattenbauten im MOE Raum zu finden sind und welche Geb��udetypologien in Deutschland am meisten zur Anwendung kamen. Diese Arbeit gibt einen ��berblick ��ber den Stand der Wissenschaft, welche Sanierungskonzepte bereits existieren, inwieweit sie praktisch umgesetzt sind und welche Verbesserungsm��glichkeiten bestehen. Untersucht wird, ob es neue innovativere L��sungsans��tze f��r die Sanierung im Bestand gibt und wie diese bereits umgesetzt sind oder aussehen k��nnten. Untersucht wird hierzu ein g��ngiger Geb��udetypus aus Deutschland - jener, der am h��ufigsten zur Anwendung kam. Es handelt sich hier um ein reines Gedankenexperiment wie man mit innovativen Systemen schaffen k��nnte, den Energieverbrauch wesentlich zu reduzieren. Bedenkt man die Gesamtfl��che der noch zu sanierenden Geb��ude, findet man auch aus marktpolitischer Sicht ein enormes Entwicklungspotential, da die Erhaltung der Bausubstanz notwendig ist und ein Abriss unm��glich. Es soll mit dieser Diplomarbeit gezeigt werden, dass es sinnvoll ist sich auch an der Fakult��t f��r Architektur mit der Forschung zu besch��ftigen, um neue und sinnvolle Methoden zur Geb��udesanierung zu entwickeln. Es wird bereits an der TU Wien mit dem Modul Experimenteller Hochbau ein Schritt in diese Richtung erm��glicht, den es gilt weiter auszubauen! Aim of the thesis is to deal critically with the issue of renovation and revitalization of prefabricated housing estates in the new European countries. This is important because this issue is present not only in the Middle East European Space (MEO), but also has become a key issue in many Western European industrial countries. Initially a historical review is made referring to Germany why these settlements have been built, how many panel buildings can be found in the CEE region and the building typologies which are the most applied in Germany. This work gives an overview of the state of scientific knowledge, which remedial concepts already exist, how they are implemented in practice and what are the opportunities for improvement. It will be investigated whether there are new innovative solutions for the renovation of existing panel buildings and how these have already been implemented or how they could look like. A common type of building in Germany - the one which most often was used - is examined as an example. We are discussing a pure thought experiment how one might manage to reduce the energy consumption significantly with the help of innovative systems. Considering the total area of the yet to be rehabilitated buildings this is quite a market perspective and an enormous development potential, the preservation of the panel buildings is the better alternative to demolition. It will be shown in this thesis that it is useful even at the Faculty of Architecture to do some research for finding new and useful methods to develop building renovation. The combination of the classic art of construction with experimental science, is able to create new technologies, appliances and additives which is already done in the module Experimental construction at the Vienna University of Technology.

Research to date has suggested that both individual marine species and ecological processes are expected to exhibit diverse responses to the environmental effects of climate change. Evolutionary responses can occur on rapid (ecological) timescales, and yet studies typically do not consider the role that adaptive evolution will play in modulating biological responses to climate change. Investigations into such responses have typically been focused at particular biological levels (e.g., cellular, population, community), often lacking interactions among levels. Since all levels of biological organisation are sensitive to global climate change, there is a need to elucidate how different processes and hierarchical interactions will influence species fitness. Therefore, predicting the responses of communities and populations to global change will require multidisciplinary efforts across multiple levels of hierarchy, from the genetic and cellular to communities and ecosystems. Eventually, this may allow us to establish the role that acclimatisation and adaptation will play in determining marine community structures in future scenarios.

The design and validation of a newly commissioned entrained flow reactor is described in the present paper. The reactor was designed for advanced studies of fuel conversion and ash formation in powder flames, and the capabilities of the reactor were experimentally validated using two different solid biomass fuels. The drop tube geometry was equipped with a flat flame burner to heat and support the powder flame, optical access ports, a particle image velocimetry (PIV) system for in situ conversion monitoring, and probes for extraction of gases and particulate matter. A detailed description of the system is provided based on simulations and measurements, establishing the detailed temperature distribution and gas flow profiles. Mass balance closures of approximately 98% were achieved by combining gas analysis and particle extraction. Biomass fuel particles were successfully tracked using shadow imaging PIV, and the resulting data were used to determine the size, shape, velocity, and residence time of converting particles. Successful extractive sampling of coarse and fine particles during combustion while retaining their morphology was demonstrated, and it opens up for detailed time resolved studies of rapid ash transformation reactions; in the validation experiments, clear and systematic fractionation trends for K, Cl, S, and Si were observed for the two fuels tested. The combination of in situ access, accurate residence time estimations, and precise particle sampling for subsequent chemical analysis allows for a wide range of future studies, with implications and possibilities discussed in the paper.

This paper presents the goals and components of a quantitative energy balance assessment framework to define PEDs flexibly in three important contexts: the context of the district's density and RES potential, the context of a district's location, induced mobility and the context of the dis-trict's future environment and its decarbonized energy demand or supply. It starts by introducing the practical goals of this definition approach: achievable, yet sufficiently ambitious to be inline with Paris 2050 for most urban and rural Austrian district typologies. It goes on to identify the main design parts of the definition: system boundaries, balancing weights and balance targets and argue how they can be linked to the definition goals in detail. In particular we specify three levels of system boundaries and argue their individual necessity: operation, including everyday mobili-ty, including embodied energy and emissions. It argues that all three pillars of PEDs, energy effi-ciency, onsite renewables and energy flexibility can be assessed with the single metric of a prima-ry energy balance when using carefully designed, time-dependent conversion factors. Finally, it is discussed how balance targets can be interpreted as information and requirements from the sur-rounding energy system, which we identify as a "context factor". Three examples of such context factors, each corresponding to the balance target of one of the previously defined system bounda-ries operation, mobility and embodied emissions are presented: Density (as a context of opera-tion), sectoral energy balances and location (as a context for mobility) and an outlook of a person-al emission budgets (as a context for embodied emissions). Finally, the proposed definition framework is applied to seven distinct district typologies in Austria and discussed in terms of its design goals.