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This studypresentsan investigation of the annual cooling load in buildings by analyzingthe influenceof parameters of phase change materials(PCMs)integrated into the envelopes of the buildings. For the use cases, well-knownCases 600 and 650 of ASHRAE Standard 140were considered. Wemodified vertical walls of the use cases incorporating various PCM layers. The impact of variousfactors of PCM layers in four climates was assessed. These factors were the thickness, melting temperature, latent heat of fusion, density, specific heat capacity, and thermal conductivity. The results showed that the variation of the density, latent heat of fusion, and the thickness of PCMs had a high impact on the reduction ofthe annual cooling energy. However, the level of thickness, latent heat of fusion, and density stuck inthe maximum value, whereas the level of thermal conductivity and specific heat capacity stuckinthe minimum value. Generally, during the globaland multi-objective optimization problems, theseparameters may beexcludedfrom the variable settingsexcept for thickness whereby the penalty function can be set. The general thermodynamic pattern of the results concludes that buildings with lightweight envelopes require as much heat storage as possiblepreventing it from theflow ofheat to the surrounding.

Biotechnology can greatly improve the efficiency of forest tree breeding for the production of biomass, energy, and materials. However, EU regulations impede the market introduction of genetically modified (GM) trees so their socioeconomic and environmental benefits are not realized. European policy makers should concentrate on a science-based regulatory process.

Recently, morphological signs of damage were reported in rabbit Achilles tendon following extracorporeal shock wave application (ESWA) with an energy flux density (EFD) of 0.6 mJ/mm(2). However, it is unknown whether or not the same can be found after ESWA to other tendons such as the quadriceps tendon.We investigated the effects of ESWA in vivo on rabbit quadriceps tendon. Animals received 1,500 SW pulses each of different EFD ranging between 0.0 and 1.2 mJ/mm(2) on either the left or right quadriceps tendon. ESWA effects were investigated by histopathological examination.ESWA with EFD of 0.5 mJ/mm(2) upwards resulted in edema within the paratenon. ESWA with EFD of 1.2 mJ/mm(2) resulted in various morphological signs of damage within the tendon and paratenon.We conclude that ESWA to the quadriceps tendon in clinical experimental use should be restricted to EFD less than 0.5 mJ/mm(2).

Correction for ‘Sustainable electrochemical synthesis of dry formaldehyde from anhydrous methanol’ by Florian Schwarz et al., Green Chem., 2024, 26, 4645–4652, https://doi.org/10.1039/D3GC04978G.

AbstractAs a regenerative energy source, tidal energy can significantly contribute to greenhouse gas reduction, even though the potentially achievable energy output is lower than that of wind or solar energy. The decisive advantage of tidal turbines lies in the simply and reliably predictable energy output. However, their commercial use has so far been impeded by the fact that on the one hand complex mechanical systems are required to convert energy of tidal currents and on the other hand multi-axial loading conditions caused by turbulent ocean currents act on the turbine. For this reason, field tests on prototypes are an essential part of the development strategy to ensure operational reliability. However, in-field tests do not allow for accelerated lifetime testing, so that test bench experiments are becoming an increasingly important alternative. Today, established procedures for testing the turbines main bearings and gearing system are already available, both for setting up the required test configuration and for determining the corresponding test loads. However, the use of advanced calculation methods, such as the finite element method for stress calculation, requires a deep understanding of the examined components and hinders the transfer of the approaches to other components.To simplify the process of test loads determination, a general methodology is presented, which relies exclusively on standardized empirical calculation rules. Doing this, fatigue equivalent loads can be determined for any component in a simple process. It was shown that the achieved reduction in complexity opens further potential for test acceleration, since several components can be tested simultaneously.

Balancing power markets involve complex procurement auction mechanisms that are challenging both to design for auctioneers and to take part in for suppliers. Recent empirical work indicates that auction results from Austria and Germany do not match game‐theoretic predictions. Instead, suppliers adjust their bids to previous auctions results and do not reveal their actual costs within their bids. Therefore, this work focuses on bidding strategies of suppliers in the Austrian and German automatically‐activated Frequency Restoration Reserve auctions. First, the operating principle of the auctions is analyzed and the cost and profit structures are illustrated. Then, a theoretic approach for the derivation of optimal bidding strategies is presented, that allows the integration of price expectations based on historical market data. We validate our approach by a numerical application of the bidder's calculus. Finally, our theoretic results are confronted with Austrian and German auction outcomes. We find evidence that the identified bidding strategies are applied by the suppliers.This article is categorized under: Energy Systems Analysis > Economics and Policy Energy Infrastructure > Economics and Policy Energy Policy and Planning > Economics and Policy Concentrating Solar Power > Economics and Policy

Abstract This study simulated the effect of time on bioenergy production from dairy manure and associated variation in energy demand and GHG emission in Ohio and Hawaii. Increasing the residence-time (RT) decreases the bioenergy-production in a nonlinear-fashion, for both the states (Ohio and Hawaii). Using the main scenario in Hawaii, the highest bioenergy production for 30 days RT was 11.2 × 104 GJ. Life-cycle-assessment of produced bioenergy showed that energy requirement and GHG emission of the produced-bioenergy (GJ) varied from 0.65 to 0.67 and 28–35 kg CO2/GJ bioenergy respectively. Year-round bioenergy production through main scenario was more advantageous with respect to bioenergy production and GHG emission. Decreasing nitrogen concentration for algal biomass production increased the bioenergy production significantly with a reduced energy demand and marginally increased GHG emission. Hence, the LCA model predicted that running a biorefinery for short residence time, and using diluted waste, could provide bioenergy with reduced energy requirement and GHG-emission.