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The adenine nucleotide translocation in mitochondria has previously been established as an exchange between exogenous and endogenous adenine nucleotides across the inner membrane. The specificity and the control of the exchange are examined with the following major results: The adenine nucleotide translocation is relatively specific for exogenous ADP and ATP, AMP being nearly inactive. Among other nucleotides tested, only dADP and dATP exchange with a noticeable activity. In the controlled state ADP exchanges 2–4 times faster than ATP. If simultaneously added, ADP and ATP compete for the exchange, with ADP being about tenfold more active than ATP. The specificity of the exit of adenine nucleotides in the exchange is similar to the specificity of the entrance with the difference that ADP and ATP are released with equal activity in proportion to their intramitochondrial content. AMP is released only after a slow conversion to ADP. Therefore the short time exchange is limited by the endogenous content of ADP plus ATP. The exchange is influenced by the metabolic state of the mitochondria. The ATP exchange is more variable than the ADP exchange. Two effects are elucidated: (a) the influence of the metabolic state on the relative content of AMP which inhibits both the ADP and ATP exchange (b) the coupling of the energy transfer system which inhibits only the ATP exchange. An example for case (a) is the inhibition of the ADP and ATP exchange by arsenate and an example for case (b) is the strong increase of the ATP exchange on uncoupling. The following effects are relevant to the mechanism of the control of the exchange by ATP. The stimulation of the ATP exchange by uncoupler has the same concentration dependence as the uncoupling of oxidative phosphorylation (Km [CCP] = 0.08 μM, where CCP = carbonyl‐cyanide‐phenylhydrazone). Oligomycin does not abolish the uncoupler effect on the ATP exchange. “Endogenous uncoupling” on aging of mitochondria also stimulates the ATP exchange. Valinomycin plus K+ only slightly stimulate the ATP exchange. Anaerobiosis stimulates the ATP exchange to a smaller extent than uncoupling.In competition with ADP the effects of energy transfer on ATP exchange are more strongly revealed. On uncoupling the more than tenfold preference for ADP is fully abolished. It is concluded that basically the exchange for ADP and ATP has equal specificity in forward and reverse reaction. In the controlled state a superimposed force makes the specificity asymmetric and inhibits the entrance of ATP. This control of the ATP exchange is concluded to be based on the anionic character of the adenine nucleotides. Thus the ATP4‐ex–ADP3‐in exchange is inhibited unless the charge difference is compensated for by an uncoupler stimulated H+ movement across the membrane. Furthermore an electric potential gradient appears to be effective in the controlled state which is abolished on uncoupling.

The energy considered as waste heat in industrial furnaces owing to inefficiencies represents a substantial opportunity for recovery by means of thermal energy storage (TES) implementation. Although conventional systems based on sensible heat are used extensively, these systems involve technical limitations. Latent heat storage based on phase change materials (PCMs) results in a promising alternative for storing and recovering waste heat. Within this scope, the proposed PCM-TES allows for demonstrating its implementation feasibility in energy-intensive industries at high temperature range. The stored energy is meant to preheat the air temperature entering the furnace by using a PCM whose melting point is 885 °C. In this sense, a heat transfer model simulation is established to determine an appropriate design based on mass and energy conservation equations. The thermal performance is analysed for the melting and solidification processes, the phase transition and its influence on heat transference. Moreover, the temperature profile is illustrated for the PCM and combustion air stream. The obtained results prove the achievability of very high temperature levels (from 700 to 865 °C) in the combustion air preheating in a ceramic furnace; so corroborating an energy and environmental efficiency enhancement, compared to the initial condition presenting an air outlet at 650 °C.

AbstractEuropean climate is associated with variability and changes in the mid-latitude atmospheric circulation. In this study, we aim to investigate potential future change in circulation over Europe by using the EURO-CORDEX regional climate projections at 0.11° grid mesh. In particular, we analyze future change in 500-hPa geopotential height (Gph), 500-hPa wind speed and mean sea level pressure (MSLP) addressing different warming levels of 1 °C, 2 °C and 3 °C, respectively. Simple scaling with the global mean temperature change is applied to the regional climate projections for monthly mean 500-hPa Gph and 500-hPa wind speed. Results from the ensemble mean of individual models show a robust increase in 500-hPa Gph and MSLP in winter over Mediterranean and Central Europe, indicating an intensification of anticyclonic circulation. This circulation change emerges robustly in most simulations within the coming decade. There are also enhanced westerlies which transport warm and moist air to the Mediterranean and Central Europe in winter and spring. It is also clear that, models showing different responses to circulation depend very much on the global climate model ensemble member in which they are nested. For all seasons, particularly autumn, the ensemble mean is much more correlated with the end of the century than most of the individual models. In general, the emergence of a scaled pattern appears rather quickly.

Abstract This paper aims to present a feasibility study of the innovative plant for methanol synthesis from carbon dioxide-sequestered by fossil fuel power plant and hydrogen, which is produced by water electrolyzer employing the over-production on the electrical grid. The thermo-economic analysis is performed in the framework of the MefCO2 H2020 EU project and it is referred to the German economic scenario, properly taking into account the real market costs and cost functions for different components of the plant. Three different plant capacities for methanol production (4000 10,000 and 50,000 ton/year) have been investigated, assuming an average cost for electrical energy to feed electrolysers and analyzing the influence of the most significant parameters (oxygen selling option, methanol selling price and electrolysers’ capital cost) on the profitability of the plant. The analysis has been performed in W-ECoMP, software for the thermo-economic analysis and plant optimization developed by the University of Genoa.

Abstract Electricity markets in Europe become increasingly interconnected due to new grid connections and market coupling regulations. This paper examines the interdependencies between the Swiss electricity market and those of neighbouring countries. The Swiss market serves as a good example for a smaller electricity market which is increasingly affected by developments in the large neighbouring countries. To study these cross-border effects, especially those on Swiss electricity prices, we apply two different methodologies, an econometric and a Nash-Cournot equilibrium model. The analyses show that the Swiss electricity price correlates strongly with the German electricity price in the summer, but tends to follow the French electricity price in the winter. Another finding is that gas prices and the electricity load of neighbouring countries have a significant influence on prices. In particular, the load of France and Italy is driving up Swiss prices in the winter, while the German electricity demand and renewable energy generation have a larger influence on Swiss prices in the summer.

Biofuels have been identified as a mid-term GHG emission abatement solution for decarbonising the transport sector. This study examines the techno-economic analysis of biofuel production via biomass fast pyrolysis and subsequent bio-oil upgrading via zeolite cracking. The aim of this study is to compare the techno-economic feasibility of two conceptual catalyst regeneration configurations for the zeolite cracking process: (i) a two-stage regenerator operating sequentially in partial and complete combustion modes (P-2RG) and (ii) a single stage regenerator operating in complete combustion mode coupled with a catalyst cooler (P-1RGC). The designs were implemented in Aspen Plus® based on a hypothetical 72 t/day pine wood fast pyrolysis and zeolite cracking plant and compared in terms of energy efficiency and profitability. The energy efficiencies of P-2RG and P-1RGC were estimated at 54% and 52%, respectively with corresponding minimum fuel selling prices (MFSPs) of £7.48/GGE and £7.20/GGE. Sensitivity analysis revealed that the MFSPs of both designs are mainly sensitive to variations in fuel yield, operating cost and income tax. Furthermore, uncertainty analysis indicated that the likely range of the MFSPs of P-1RGC (£5.81/GGE  £11.63/GGE) at 95% probability was more economically favourable compared with P-2RG, along with a penalty of 2% reduction in energy efficiency. The results provide evidence to support the economic viability of biofuel production via zeolite cracking of pyrolysis-derived bio-oil.

This article makes the central argument that basic democratic values such as justice, autonomy and participation run the risk of being neglected when designing ‘nudges’ (i.e., indirect suggestions to influence individual behaviour) for sustainable behaviour change in the context of food governance, potentially complicating a democratisation of the food system. ‘Nudges’ uphold freedom of choice while simultaneously advocating a non-coercive soft force of paternalism to help people realise their preferences, maximise societal well-being and meet macro-sustainability goals. While the promises of the ‘nudge’ approach are widely echoed, nudging is also being contested because of its possible anti-democratic effects, such as individualisation, depoliticization and the emphasis of the status of citizens as ‘consumer-citizens.’ From a food democracy perspective, these dangers may undermine efforts to organise collective political action and impede alternative visions of a future food system. Empirically, the article examines specifically how behavioural-economic approaches imagine transitions to a more sustainable food system. By using the “COOP Supermarket of the Future” as a case study, the following analysis will illustrate how private actors are increasingly involved in steering consumer choice towards socially desirable actions. The analysis suggests that the design of choice environments may under specific circumstances increase the susceptibility of individuals to the influence of corporate preferences and simultaneously decrease the prospects for democratic legitimation and decision-making. The article therefore critically assesses whether reforming the food system by altering consumers’ choice-sets and the attribution of personal responsibility, may in fact point towards implicit anti-democratic tenets underlying the ‘will to nudge’ citizens.