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Abstract Efficiency of the earth-to-air heat exchangers depends not only on their thermal performance but also on the total pressure losses that are the cost of harvesting a geothermal heat. In this paper the sensitivity analysis of the flow characteristics to the change of multi-pipe exchanger geometry is presented. Experimental investigation and CFD simulation results present total pressure losses in the considered exchangers and airflows in each branch-pipes. Considered geometrical structures varies in the number of parallel pipes, pipes length, main pipes diameters and supply type. The experimental investigations were conducted on the exchangers models in a scale 1:4. To investigate the real size exchangers, validated CFD flow performance model was used. A costless modification of heat exchanger supply-type from Z-type to U-type structure (change in air inlet location) is verified as a simple method of decreasing total pressure losses by 6–36% and improving airflow division uniformity by 11–80%. It is shown that main pipes diameter that are 1.4 times bigger than parallel pipes diameter can result in diminished total pressure losses by 56–73% and improved airflow division uniformity by 6–59%. The least significant effect on the flow characteristics has the branch-pipe length. Total pressure losses of long branch-pipes exchangers can be 15–32% higher than for short ones and the airflow division uniformity can be 8–35% higher. Results can be used for choosing the proper geometry of multi-pipe earth-to-air heat exchangers from the flow performance point of view. Presented flow characteristics can be used in detailed analysis and energy assessment of exchangers cooperating with the mechanical ventilation system in building.

Abstract The direct carbon fuel cells with solid oxide electrolyte (DC-SOFC) and anodes deposited by inject printing (EM/DCIJP) were studied. The cells were fed with carbon fuel obtained by the direct RF plasma splitting of methane. Since the (EM/DCIJP)M/DCIJP technology allows easy modification of electrode material, the effect of Cu addition to the Ni–YSZ anode was investigated. The significant improvement of the cell performance with the new anode was observed.

Human diamine oxidase (hDAO, EC 1.4.3.22) is the key enzyme in the degradation of extracellular histamine. Consumption of alcohol is a known trigger of mast cell degranulation in patients with mast cell activation syndrome. Ethanol may also interfere with enzymatic histamine degradation, but reports on the effects on DAO activity are controversial. There are also conflicting reports whether disulfiram, an FDA-approved agent in the treatment of alcohol dependence, inhibits DAO. We therefore investigated the inhibitory potential of ethanol and disulfiram and their metabolites on recombinant human DAO (rhDAO) in three different assay systems. Relevant concentrations of ethanol, acetaldehyde, and acetate did not inhibit rhDAO activity in an in vitro assay system using horseradish peroxidase (HRP) -mediated luminol oxidation. The aldehyde dehydrogenase (ALDH; EC 1.2.1.3) inhibitors cyanamide and its dimer dicyanamide also had no effect on DAO activity. In one assay system, the irreversible ALDH inhibitor disulfiram and its main metabolite diethyldithiocarbamate seemed to inhibit DAO activity. However, the decreased product formation was not due to a direct block of DAO activity but resulted from inhibition of peroxidase employed in the coupled system. Our in vitro data do not support a direct blocking effect of ethanol, disulfiram, and their metabolites on DAO activity in vivo.

Abstract Demand response aims to change the energy consumption patterns of normal customers in response to changes in price rate or incentive offers. This process reduces peak loads and in turn potentially lowers the energy cost for customers. In this study, we propose a new demand response scheme on the basis of an adaptive consumption level pricing scheme. On the one hand, this strategy encourages customers to manage their energy consumption and consequently lower their energy bill. On the other hand, it allows utilities to manage the aggregate consumption and predict load requirement. Unlike other pricing schemes, such as block tariff and time-of-use, the proposed pricing scheme can lower the energy bill of about 73% of customers, assuming that the total utility revenue is the same for all pricing schemes. On the basis of the currently available schemes in the literature, we find that the proposed method has significant advantages over other schemes in terms of fairness in charging customers.

Abstract Using the method of hot-wall epitaxy, layers of n-type CdTe and CdS doped with indium were grown on monocrystalline BaF 2 and SrF 2 substrates, respectively. Typical electron concentrations of up to 2 × 10 17 cm −3 in CdTe and 3 × 10 18 cm −3 in CdS were obtained. At room temperature we measured mobilities of 600 cm 2 /Vs for CdTe and 230 cm 2 /Vs for CdS. The mobility of some samples increased exponentially with temperature in the temperature range of 300 to 100 K. This effect can be explained by means of a grain boundary model. However, in other samples bulk scattering mechanisms play a significant role for temperatures lower than 100 K. The mobility as a function of grain size was also investigated. For the characterization of carrier traps in the CdTe films we performed deep level transient spectroscopy measurements. We found six different defect levels in the upper half of the forbidden gap. It was determined that the concentration of the defects and their distribution with depth away from the interface in heterojunction diodes were a function of the growth conditions. Using temperatures of only 350 K we were able to reduce the concentration of two of the defects in the CdTe layers.

EU climate and energy policy defines ambitious objectives for the Member States, requiring a fundamental change in energy systems. In an interdisciplinary approach, starting with welfare-generating energy services instead of energy flows, we analyse restructuring options for the Austrian energy system. We extend the concept of stabilization wedges by Pacala and Socolow and integrate technological and behavioural options into a structural energy model, complemented by an economic evaluation in an input-output analysis. We apply the energy service based approach to a transformation of the Austrian energy system that meets the EU 2020 emission targets. We estimate that this would require on average additional investment of about 6 billion € p.a. over a twelve year period. This investment allows to tap savings in operating costs (predominantly energy costs) of up to 4.3 billion € at the end of the period, when using a conservative assumption of non-rising energy prices.

Hydrogen ingress into a metal has been observed at cavitation in distilled water and in 3% NaCl solution at open circuit potential. The measurements of hydrogen permeation rate have been made using an ultrasonic cavitation facility with an attached Devanathan-Stachurski double cell. Increase in vibration amplitude has been associated with the increase in amplitude of electrochemical voltage and current pulses and with the modification of hydrogen permeation rate. Hydrogen behavior within the metal has been affected by the cavitation induced dynamic stresses and metal deformation hardening, ascertained on the basis of the appearance of hydrogen permeation transients at cavitation in comparison with those recorded for the unstressed state. Metal damage has been a resultof associated effects of cavitation and hydrogen.

This paper presents an integrated vehicle model to simulate simultaneously the driver, powertrains, chassis, body, road condition, vehicle dynamics and the Active Suspension (AS) system with/without an energy harvesting module. The developed model is used to investigate the ride comfort and influences of energy harvesting AS system on the total energy consumption of battery Electric Vehicles (EVs) relative to EVs with a passive suspension system. Preliminary simulation results show that compared to EVs with a passive suspension system, the ones with AS system improve ride comfort, up to 31% reduction of the vehicle body acceleration RMS value, with an expense of higher energy consumption. This expense can be reduced to about 2.8% when using an energy harvesting AS system. Simulation results also demonstrate that the available energy for recuperation during the AS system operation is significant in relation to the regenerative braking energy of the propulsion system, up to approx. 70% on bumpy road surfaces.

The study of the biological mechanisms of ethanol reward has greatly suffered from problems to obtain ethanol-induced conditioned place preference (CPP) in rats. In the present study, CPP was obtained in genetically selected Marchigian Sardinian alcohol-preferring (msP) rats, derived from Sardinian alcohol-preferring rats, following intragastric (IG) ethanol administration by means of a permanent IG catheter, but not after intraperitoneal (IP) injection or IG gavage. Rats with permanent IG catheter, received IG administration of 0.35, 0.7, 1.5 or 2.8 g/kg ethanol, as a 10% v/v solution. In ethanol-experienced rats 0.7 or 1.5, but not 0.35 or 2.8 g/kg ethanol significantly increased in comparison to controls the time spent in the ethanol-associated previously non-preferred compartment, which became preferred in the post-conditioning test. In ethanol-naive rats, only 0.7 g/kg ethanol significantly increased the time spent in the ethanol-associated compartment. On the other hand, no effect was observed in alcohol-experienced rats following IG gavage, or IP injection of 0.35, 0.7 or 1.5 g/kg ethanol. The present results provide evidence that ethanol possesses postingestive rewarding properties in msP rats, and that it can reliably induce CPP in them, provided that an appropriate method of administration is adopted.