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This study addresses the critical need for a constitutive model to analyze the cyclic plasticity of additively manufactured 316L stainless steel. The anisotropic behavior at both room temperature and 300 degrees C is investigated experimentally based on cyclic hysteresis loops performed in different orientations with respect to the build direction. A comprehensive constitutive model is proposed, that integrates the Armstrong-Frederick nonlinear kinematic hardening, Voce nonlinear isotropic hardening and Hill's anisotropic yield criterion within a 3D return mapping algorithm. The model was calibrated to specimens in the 0 degrees and 90 degrees orientations and validated with specimens in the 45 degrees orientation. A single set of hardening parameters successfully represented the elastoplastic response for all orientations at room temperature. The algorithm effectively captured the full cyclic hysteresis loops, including historical effects observed in experimental tests. A consistent trend of reduced hardening was observed at elevated temperature, while the 45 degrees specimen orientation consistently exhibited the highest degree of strain hardening. The applicability of the model was demonstrated by computing energy dissipation for stabilized hysteresis loops, which was combined with fatigue tests to propose an energy-based fatigue life prediction model.

This study addresses the critical need for a constitutive model to analyze the cyclic plasticity of additively manufactured 316L stainless steel. The anisotropic behavior at both room temperature and 300 degrees C is investigated experimentally based on cyclic hysteresis loops performed in different orientations with respect to the build direction. A comprehensive constitutive model is proposed, that integrates the Armstrong-Frederick nonlinear kinematic hardening, Voce nonlinear isotropic hardening and Hill's anisotropic yield criterion within a 3D return mapping algorithm. The model was calibrated to specimens in the 0 degrees and 90 degrees orientations and validated with specimens in the 45 degrees orientation. A single set of hardening parameters successfully represented the elastoplastic response for all orientations at room temperature. The algorithm effectively captured the full cyclic hysteresis loops, including historical effects observed in experimental tests. A consistent trend of reduced hardening was observed at elevated temperature, while the 45 degrees specimen orientation consistently exhibited the highest degree of strain hardening. The applicability of the model was demonstrated by computing energy dissipation for stabilized hysteresis loops, which was combined with fatigue tests to propose an energy-based fatigue life prediction model.

This study addresses the critical need for a constitutive model to analyze the cyclic plasticity of additively manufactured 316L stainless steel. The anisotropic behavior at both room temperature and 300 degrees C is investigated experimentally based on cyclic hysteresis loops performed in different orientations with respect to the build direction. A comprehensive constitutive model is proposed, that integrates the Armstrong-Frederick nonlinear kinematic hardening, Voce nonlinear isotropic hardening and Hill's anisotropic yield criterion within a 3D return mapping algorithm. The model was calibrated to specimens in the 0 degrees and 90 degrees orientations and validated with specimens in the 45 degrees orientation. A single set of hardening parameters successfully represented the elastoplastic response for all orientations at room temperature. The algorithm effectively captured the full cyclic hysteresis loops, including historical effects observed in experimental tests. A consistent trend of reduced hardening was observed at elevated temperature, while the 45 degrees specimen orientation consistently exhibited the highest degree of strain hardening. The applicability of the model was demonstrated by computing energy dissipation for stabilized hysteresis loops, which was combined with fatigue tests to propose an energy-based fatigue life prediction model.

This study addresses the critical need for a constitutive model to analyze the cyclic plasticity of additively manufactured 316L stainless steel. The anisotropic behavior at both room temperature and 300 °C is investigated experimentally based on cyclic hysteresis loops performed in different orientations with respect to the build direction. A comprehensive constitutive model is proposed, that integrates the Armstrong-Frederick nonlinear kinematic hardening, Voce nonlinear isotropic hardening and Hill's anisotropic yield criterion within a 3D return mapping algorithm. The model was calibrated to specimens in the 0° and 90° orientations and validated with specimens in the 45° orientation. A single set of hardening parameters successfully represented the elastoplastic response for all orientations at room temperature. The algorithm effectively captured the full cyclic hysteresis loops, including historical effects observed in experimental tests. A consistent trend of reduced hardening was observed at elevated temperature, while the 45° specimen orientation consistently exhibited the highest degree of strain hardening. The applicability of the model was demonstrated by computing energy dissipation for stabilized hysteresis loops, which was combined with fatigue tests to propose an energy-based fatigue life prediction model., QC 20240514

The quantification of the influence of the weather conditions has a great importance in the field of Structural Heath Monitoring (SHM). In this work, the KTH two-span post-tensioned concrete bridge is studied. A shell based Finite Element (FE) model and a 3D solid FE-model are made. A sensitivity analysis of the dynamic properties of the system, i.e. natural frequencies and mode shapes is performed considering the influence of the boundary conditions, the elastic modulus of concrete, the material properties of the asphalt layer, the expansion joints of the bridge and the interaction between the deck and the abutments of the system. Furthermore, an experimental campaign was performed during winter weather conditions and compared to a previously developed study of the same system during autumn weather conditions. The results show the great influence the weather conditions on the dynamic properties of the system as well as the limitation, uncertainties and the problem of the unicity of the solution for the calibration of the developed FE-models. The case study shows the importance of SHM not only for tracking the dynamic properties of the studied system and early detection of global changes of the system but also how performing measurements can help to reduce the inherent uncertainties associated to a FE-model to improve the current engineering practice., Part of ISBN [9783031614248]QC 20240830

This study addresses the critical need for a constitutive model to analyze the cyclic plasticity of additively manufactured 316L stainless steel. The anisotropic behavior at both room temperature and 300 degrees C is investigated experimentally based on cyclic hysteresis loops performed in different orientations with respect to the build direction. A comprehensive constitutive model is proposed, that integrates the Armstrong-Frederick nonlinear kinematic hardening, Voce nonlinear isotropic hardening and Hill's anisotropic yield criterion within a 3D return mapping algorithm. The model was calibrated to specimens in the 0 degrees and 90 degrees orientations and validated with specimens in the 45 degrees orientation. A single set of hardening parameters successfully represented the elastoplastic response for all orientations at room temperature. The algorithm effectively captured the full cyclic hysteresis loops, including historical effects observed in experimental tests. A consistent trend of reduced hardening was observed at elevated temperature, while the 45 degrees specimen orientation consistently exhibited the highest degree of strain hardening. The applicability of the model was demonstrated by computing energy dissipation for stabilized hysteresis loops, which was combined with fatigue tests to propose an energy-based fatigue life prediction model.

This study addresses the critical need for a constitutive model to analyze the cyclic plasticity of additively manufactured 316L stainless steel. The anisotropic behavior at both room temperature and 300 degrees C is investigated experimentally based on cyclic hysteresis loops performed in different orientations with respect to the build direction. A comprehensive constitutive model is proposed, that integrates the Armstrong-Frederick nonlinear kinematic hardening, Voce nonlinear isotropic hardening and Hill's anisotropic yield criterion within a 3D return mapping algorithm. The model was calibrated to specimens in the 0 degrees and 90 degrees orientations and validated with specimens in the 45 degrees orientation. A single set of hardening parameters successfully represented the elastoplastic response for all orientations at room temperature. The algorithm effectively captured the full cyclic hysteresis loops, including historical effects observed in experimental tests. A consistent trend of reduced hardening was observed at elevated temperature, while the 45 degrees specimen orientation consistently exhibited the highest degree of strain hardening. The applicability of the model was demonstrated by computing energy dissipation for stabilized hysteresis loops, which was combined with fatigue tests to propose an energy-based fatigue life prediction model.

Similar to wood, adhesives may exhibit duration of load effects. When loaded for longer periods of time, damage processes in the material may develop, eventually leading to failure. From wood research it is known that load level, temperature and relative humidity have an important influence on this behaviour. In general, higher stress levels, temperatures, and moisture content will lead to shorter times to failure and these effects may be more pronounced in loading directions such as shear or tension perpendicular to the grain. It is shown that the reaction kinetics based approach for damage accumulation effects in polyurethane based adhesives can be described using the same non-linear damage accumulation expression as used for wood. The relationship between the time to failure and load-level as influenced by for instance temperature is determined for lap joints, immersed in hot water with temperature of 60oC and 90oC, and at load levels varying between 30 and 90% of the mean short term shear strength. It is shown that a non-linear damage accumulation expression as used for wood, can also be used for damage accumulation effects in melamine-urea-formaldehyde adhesives. The relationship between the time to failure and load-level as influenced by temperature is determined for beech lap joints loaded in tensile shear. The specimens have been immersed in hot water with temperatures of 60oC and 90oC respectively, and at load levels varying between 30 and 90% of the mean short term shear strength., Bio-based Structures & Materials

One of the main challenges for bridge damage identification using monitoring data is to acquire sensitive damage features but insensitive to operational and environmental effects as well as noise. Specifically, the temperature as part of environmental variability can mask structural damages in bridges. Principal Component Analysis (PCA) has been applied here as a well-known and robust technique for removing environmental variability and obtain damage-sensitive indices. As a first aim, PCA is used considering only ambient vibrations and the natural frequencies are considered as damage indicators. As a second objective, PCA in conjunction with Hilbert Huang Transform (HHT) and Variational Mode Decomposition (VMD) are applied to eliminate the environmental influence in transient vibrations due to traffic. The combined methodology is applied to the case of a numerical benchmark by using the Instantaneous Phase Difference (IPD) as novel vibration damage feature in the case of non-stationary vibrations. The results show that the proposed strategy to use the non-stationary vibration due to traffic instead of ambient vibration seems a promising tool for damage identification and, therefore, its capabilities in real bridge applications are worth exploring further when experimental data from real bridges will become available., The authors thank Prof. Eleni Chatzi, ETH Zurich, for giving us the data as well as documentation from the numerical bridge utilized in the case study. To the Dirección de Investigación de la Universidad Peruana de Ciencias Aplicadas for the support provided for the realization of this research work through the UPC-EXPOST-2023-1 incentive., Peer Reviewed, Postprint (author's final draft)

Climate change has been projected to cause increased temperature and amplified inflows of terrestrial organic matter to coastal areas in northern Europe. Consequently, changes at the base of the food web favoring heterotrophic bacteria over phytoplankton are expected, affecting the food web structure. We tested this hypothesis using an outdoor shallow mesocosm system in the northern Baltic Sea in early summer, where the effects of increased temperature (+ 3°C) and terrestrial matter inputs were studied following the system dynamics and conducting grazing experiments. Juvenile perch constituted the highest trophic level in the system, which exerted strong predation on the zooplankton community. Perch subsequently released the microbial food web from heavy grazing by mesozooplankton. Addition of terrestrial matter had a stronger effect on the microbial food web than the temperature increase, because terrestrial organic matter and accompanying nutrients promoted both heterotrophic bacterial production and phytoplankton primary production. Moreover, due to the shallow water column in the experiment, terrestrial matter addition did not reduce the light below the photosynthesis saturation level, and in these conditions, the net-autotrophy was strengthened by terrestrial matter enrichment. In combination with elevated temperature, the terrestrial matter addition effects were intensified, further shifting the size distribution of the microbial food web base from picoplankton to microphytoplankton. These changes up the food web led to increase in the biomass and proportion of large-sized ciliates (>60 µm) and rotifers. Despite the shifts in the microbial food web size structure, grazing experiments suggested that the pathway from picoplankton to nano- and microzooplankton constituted the major energy flow in all treatments. The study implies that the microbial food web compartments in shallow coastal waters will adjust to climate induced increased inputs of terrestrial ma

Climate change has been projected to cause increased temperature and amplified inflows of terrestrial organic matter to coastal areas in northern Europe. Consequently, changes at the base of the food web favoring heterotrophic bacteria over phytoplankton are expected, affecting the food web structure. We tested this hypothesis using an outdoor shallow mesocosm system in the northern Baltic Sea in early summer, where the effects of increased temperature (+ 3°C) and terrestrial matter inputs were studied following the system dynamics and conducting grazing experiments. Juvenile perch constituted the highest trophic level in the system, which exerted strong predation on the zooplankton community. Perch subsequently released the microbial food web from heavy grazing by mesozooplankton. Addition of terrestrial matter had a stronger effect on the microbial food web than the temperature increase, because terrestrial organic matter and accompanying nutrients promoted both heterotrophic bacterial production and phytoplankton primary production. Moreover, due to the shallow water column in the experiment, terrestrial matter addition did not reduce the light below the photosynthesis saturation level, and in these conditions, the net-autotrophy was strengthened by terrestrial matter enrichment. In combination with elevated temperature, the terrestrial matter addition effects were intensified, further shifting the size distribution of the microbial food web base from picoplankton to microphytoplankton. These changes up the food web led to increase in the biomass and proportion of large-sized ciliates (>60 µm) and rotifers. Despite the shifts in the microbial food web size structure, grazing experiments suggested that the pathway from picoplankton to nano- and microzooplankton constituted the major energy flow in all treatments. The study implies that the microbial food web compartments in shallow coastal waters will adjust to climate induced increased inputs of terrestrial ma

Plastic waste poses a significant hazard to the environment as a result of its high production rates, which endanger both the environment and its inhabitants. Similarly, another concern is the production of cement, which accounts for roughly 8% of global CO2 emissions. Thus, recycling plastic waste as a replacement for cementitious materials may be a more effective strategy for waste minimisation and cement elimination. Therefore, in this study, plastic waste (low-density polyethylene) is utilised in the production of plastic sand paver blocks without the use of cement. In addition to this, basalt fibers which is a green industrial material is also added in the production of eco-friendly plastic sand paver blocks to satisfy the standard of ASTM C902-15 of 20 N/mm2 for the light traffic. In order to make the paver blocks, the LDPE waste plastic was melted outside in the open air and then combined with sand. Variations were made to the ratio of LDPE to sand, the proportion of basalt fibers, and sand particle size. Paver blocks were evaluated for their compressive strength, water absorption, and at different temperatures. Including 0.5% percent basalt fiber of length 4 mm gives us the best result by enhancing compressive strength by 20.5% and decreasing water absorption by 50.5%. The best results were obtained with a ratio of 30:70 LDPE to sand, while the finest sand provides the greatest compressive strength. Moreover, the temperature effect was also studied from 0 to 60 °C, and the basalt fibers incorporated in plastic paver blocks showed only a 20% decrease in compressive strength at 60 °C. This research has produced eco-friendly paver blocks by removing cement and replacing it with plastic waste, which will benefit the environment, save money, reduce carbon dioxide emissions, and be suitable for low-traffic areas, all of which contribute to sustainable development., Validerad;2023;Nivå 2;2023-06-21 (hanlid);Funder: Ministry of Higher Education of Malaysia and Universiti Teknologi Malaysia (5F545, 4J224); Prince Sattam bin Abdulaziz University (PSAU/2023/R/1444)

Climate change has been projected to cause increased temperature and amplified inflows of terrestrial organic matter to coastal areas in northern Europe. Consequently, changes at the base of the food web favoring heterotrophic bacteria over phytoplankton are expected, affecting the food web structure. We tested this hypothesis using an outdoor shallow mesocosm system in the northern Baltic Sea in early summer, where the effects of increased temperature (+ 3°C) and terrestrial matter inputs were studied following the system dynamics and conducting grazing experiments. Juvenile perch constituted the highest trophic level in the system, which exerted strong predation on the zooplankton community. Perch subsequently released the microbial food web from heavy grazing by mesozooplankton. Addition of terrestrial matter had a stronger effect on the microbial food web than the temperature increase, because terrestrial organic matter and accompanying nutrients promoted both heterotrophic bacterial production and phytoplankton primary production. Moreover, due to the shallow water column in the experiment, terrestrial matter addition did not reduce the light below the photosynthesis saturation level, and in these conditions, the net-autotrophy was strengthened by terrestrial matter enrichment. In combination with elevated temperature, the terrestrial matter addition effects were intensified, further shifting the size distribution of the microbial food web base from picoplankton to microphytoplankton. These changes up the food web led to increase in the biomass and proportion of large-sized ciliates (>60 µm) and rotifers. Despite the shifts in the microbial food web size structure, grazing experiments suggested that the pathway from picoplankton to nano- and microzooplankton constituted the major energy flow in all treatments. The study implies that the microbial food web compartments in shallow coastal waters will adjust to climate induced increased inputs of terrestrial ma

Plastic waste poses a significant hazard to the environment as a result of its high production rates, which endanger both the environment and its inhabitants. Similarly, another concern is the production of cement, which accounts for roughly 8% of global CO2 emissions. Thus, recycling plastic waste as a replacement for cementitious materials may be a more effective strategy for waste minimisation and cement elimination. Therefore, in this study, plastic waste (low-density polyethylene) is utilised in the production of plastic sand paver blocks without the use of cement. In addition to this, basalt fibers which is a green industrial material is also added in the production of eco-friendly plastic sand paver blocks to satisfy the standard of ASTM C902-15 of 20 N/mm2 for the light traffic. In order to make the paver blocks, the LDPE waste plastic was melted outside in the open air and then combined with sand. Variations were made to the ratio of LDPE to sand, the proportion of basalt fibers, and sand particle size. Paver blocks were evaluated for their compressive strength, water absorption, and at different temperatures. Including 0.5% percent basalt fiber of length 4 mm gives us the best result by enhancing compressive strength by 20.5% and decreasing water absorption by 50.5%. The best results were obtained with a ratio of 30:70 LDPE to sand, while the finest sand provides the greatest compressive strength. Moreover, the temperature effect was also studied from 0 to 60 °C, and the basalt fibers incorporated in plastic paver blocks showed only a 20% decrease in compressive strength at 60 °C. This research has produced eco-friendly paver blocks by removing cement and replacing it with plastic waste, which will benefit the environment, save money, reduce carbon dioxide emissions, and be suitable for low-traffic areas, all of which contribute to sustainable development., Validerad;2023;Nivå 2;2023-06-21 (hanlid);Funder: Ministry of Higher Education of Malaysia and Universiti Teknologi Malaysia (5F545, 4J224); Prince Sattam bin Abdulaziz University (PSAU/2023/R/1444)

Climate change has been projected to cause increased temperature and amplified inflows of terrestrial organic matter to coastal areas in northern Europe. Consequently, changes at the base of the food web favoring heterotrophic bacteria over phytoplankton are expected, affecting the food web structure. We tested this hypothesis using an outdoor shallow mesocosm system in the northern Baltic Sea in early summer, where the effects of increased temperature (+ 3°C) and terrestrial matter inputs were studied following the system dynamics and conducting grazing experiments. Juvenile perch constituted the highest trophic level in the system, which exerted strong predation on the zooplankton community. Perch subsequently released the microbial food web from heavy grazing by mesozooplankton. Addition of terrestrial matter had a stronger effect on the microbial food web than the temperature increase, because terrestrial organic matter and accompanying nutrients promoted both heterotrophic bacterial production and phytoplankton primary production. Moreover, due to the shallow water column in the experiment, terrestrial matter addition did not reduce the light below the photosynthesis saturation level, and in these conditions, the net-autotrophy was strengthened by terrestrial matter enrichment. In combination with elevated temperature, the terrestrial matter addition effects were intensified, further shifting the size distribution of the microbial food web base from picoplankton to microphytoplankton. These changes up the food web led to increase in the biomass and proportion of large-sized ciliates (>60 µm) and rotifers. Despite the shifts in the microbial food web size structure, grazing experiments suggested that the pathway from picoplankton to nano- and microzooplankton constituted the major energy flow in all treatments. The study implies that the microbial food web compartments in shallow coastal waters will adjust to climate induced increased inputs of terrestrial ma

One of the first water treatment technologies used by humans is Reverse Osmosis (RO). It has become a sustainable alternative solution to the problem of water scarcity in the current world conditions. In this research, the effects of temperature and pH on efficiency, energy consumption, and outlet water quality from simple single-stage RO systems, single-stage hybrid, simple two-stage, and two-stage hybrid are investigated using RO software. The results depict that at all temperatures, the two-stage RO system is more efficient in terms of efficiency, and the hybrid two-stage system has the best performance in terms of energy consumption. Moreover, the pH of the water entering the system has no effect on the efficiency and energy consumption of desalination plants. In terms of water quality, all the four desalination plants reduced the concentration of harmful ions to the desired level, but single-stage systems outperformed two-stage systems. In terms of corrosion index, two-stage systems outperformed single-stage systems. Furthermore, the corrosion rate of water could be significantly reduced by increasing the temperature and adding sodium hydroxide. In addition, the obtained results showed that the operating pressure on the RO system decreased as the temperature increased. © 2022 Sharif University of Technology. All rights reserved.

One of the first water treatment technologies used by humans is Reverse Osmosis (RO). It has become a sustainable alternative solution to the problem of water scarcity in the current world conditions. In this research, the effects of temperature and pH on efficiency, energy consumption, and outlet water quality from simple single-stage RO systems, single-stage hybrid, simple two-stage, and two-stage hybrid are investigated using RO software. The results depict that at all temperatures, the two-stage RO system is more efficient in terms of efficiency, and the hybrid two-stage system has the best performance in terms of energy consumption. Moreover, the pH of the water entering the system has no effect on the efficiency and energy consumption of desalination plants. In terms of water quality, all the four desalination plants reduced the concentration of harmful ions to the desired level, but single-stage systems outperformed two-stage systems. In terms of corrosion index, two-stage systems outperformed single-stage systems. Furthermore, the corrosion rate of water could be significantly reduced by increasing the temperature and adding sodium hydroxide. In addition, the obtained results showed that the operating pressure on the RO system decreased as the temperature increased. © 2022 Sharif University of Technology. All rights reserved.

Otoliths are very useful biomarkers especially for fish growth. Climate change with the associated global changes in warming and acidification could affect the calcification and the shape of otoliths during the crucial larval period in teleost fish. To evaluate this predicted combined effect of temperature and CO2, Atlantic herring (Clupea harengus) embryos and larvae were reared from hatching to respectively 47 and 60 days post-hatching (dph), under present day conditions and a scenario predicted for the year 2100 (IPCC RCP8.5). Otolith morphogenesis was tracked by analyzing area and normalized Elliptical Fourier coefficients. We found that otolith area for fish of similar size increased under the predicted 2100 climate change scenario compared to the present day. Climate change does not, however, seem to directly affect the otolith shape. Finally, the onset of otolith morphogenesis is hardwired, but the relationship between otolith and fish size is environment-dependent.

African Swine Fever Virus (ASFV) is the cause of an infectious disease in pigs, which is difficult to control. Long viability of ASFV has been shown for several contaminated materials, especially under low temperature. Therefore, when pigs are exposed to a contaminated environment, new infections could occur without the presence of infectious individuals. For example, a contaminated, poorly washed, empty livestock vehicle poses a risk to the next load of pigs. A quantitative stochastic environmental transmission model was applied to simulate the change in environmental contamination levels over time and calculate the epidemic parameters through exposure-based estimation. Due to the lack of experimental data on environmental transmission at low temperatures, we performed a non-linear fit of the decay rate parameter with temperature based on a literature review. Eventually, 16 scenarios were constructed for different temperature (at 20 °C, 10 °C, 0 °C, or −10 °C) and duration of empty periods (1, 3, 5, or 7 days) after the environment had been contaminated. We quantified the variation in the contamination level of the environment over time and the probability of newly added recipients getting infected when exposed to the environment after the empty period. As a result, the transmission rate parameter for ASFV in pigs was estimated to be 1.53 (0.90, 2.45) day-1, the decay rate parameter to be 1.02 (0.73, 1.47) day-1 (at 21 °C), and the excretion rate parameter to be 2.70 (2.51, 3.02) day-1. Without washing and disinfecting, the environment required 9, 14, 24, 54 days to reach a low probability of causing at least one new case (<0.005) at 20 °C, 10 °C, 0 °C, −10 °C, respectively. In addition, the method proposed in this paper enables assessment of the effect of washing and disinfecting on ASFV environmental transmission. We conducted this study to better understand how the viability of ASFV at different temperatures could affect th

African Swine Fever Virus (ASFV) is the cause of an infectious disease in pigs, which is difficult to control. Long viability of ASFV has been shown for several contaminated materials, especially under low temperature. Therefore, when pigs are exposed to a contaminated environment, new infections could occur without the presence of infectious individuals. For example, a contaminated, poorly washed, empty livestock vehicle poses a risk to the next load of pigs. A quantitative stochastic environmental transmission model was applied to simulate the change in environmental contamination levels over time and calculate the epidemic parameters through exposure-based estimation. Due to the lack of experimental data on environmental transmission at low temperatures, we performed a non-linear fit of the decay rate parameter with temperature based on a literature review. Eventually, 16 scenarios were constructed for different temperature (at 20 °C, 10 °C, 0 °C, or −10 °C) and duration of empty periods (1, 3, 5, or 7 days) after the environment had been contaminated. We quantified the variation in the contamination level of the environment over time and the probability of newly added recipients getting infected when exposed to the environment after the empty period. As a result, the transmission rate parameter for ASFV in pigs was estimated to be 1.53 (0.90, 2.45) day-1, the decay rate parameter to be 1.02 (0.73, 1.47) day-1 (at 21 °C), and the excretion rate parameter to be 2.70 (2.51, 3.02) day-1. Without washing and disinfecting, the environment required 9, 14, 24, 54 days to reach a low probability of causing at least one new case (<0.005) at 20 °C, 10 °C, 0 °C, −10 °C, respectively. In addition, the method proposed in this paper enables assessment of the effect of washing and disinfecting on ASFV environmental transmission.

Climate change has been projected to cause increased temperature and amplified inflows of terrestrial organic matter to coastal areas in northern Europe. Consequently, changes at the base of the food web favoring heterotrophic bacteria over phytoplankton are expected, affecting the food web structure. We tested this hypothesis using an outdoor shallow mesocosm system in the northern Baltic Sea in early summer, where the effects of increased temperature (+ 3°C) and terrestrial matter inputs were studied following the system dynamics and conducting grazing experiments. Juvenile perch constituted the highest trophic level in the system, which exerted strong predation on the zooplankton community. Perch subsequently released the microbial food web from heavy grazing by mesozooplankton. Addition of terrestrial matter had a stronger effect on the microbial food web than the temperature increase, because terrestrial organic matter and accompanying nutrients promoted both heterotrophic bacterial production and phytoplankton primary production. Moreover, due to the shallow water column in the experiment, terrestrial matter addition did not reduce the light below the photosynthesis saturation level, and in these conditions, the net-autotrophy was strengthened by terrestrial matter enrichment. In combination with elevated temperature, the terrestrial matter addition effects were intensified, further shifting the size distribution of the microbial food web base from picoplankton to microphytoplankton. These changes up the food web led to increase in the biomass and proportion of large-sized ciliates (>60 µm) and rotifers. Despite the shifts in the microbial food web size structure, grazing experiments suggested that the pathway from picoplankton to nano- and microzooplankton constituted the major energy flow in all treatments. The study implies that the microbial food web compartments in shallow coastal waters will adjust to climate induced increased inputs of terrestrial ma

Climate change has been projected to cause increased temperature and amplified inflows of terrestrial organic matter to coastal areas in northern Europe. Consequently, changes at the base of the food web favoring heterotrophic bacteria over phytoplankton are expected, affecting the food web structure. We tested this hypothesis using an outdoor shallow mesocosm system in the northern Baltic Sea in early summer, where the effects of increased temperature (+ 3°C) and terrestrial matter inputs were studied following the system dynamics and conducting grazing experiments. Juvenile perch constituted the highest trophic level in the system, which exerted strong predation on the zooplankton community. Perch subsequently released the microbial food web from heavy grazing by mesozooplankton. Addition of terrestrial matter had a stronger effect on the microbial food web than the temperature increase, because terrestrial organic matter and accompanying nutrients promoted both heterotrophic bacterial production and phytoplankton primary production. Moreover, due to the shallow water column in the experiment, terrestrial matter addition did not reduce the light below the photosynthesis saturation level, and in these conditions, the net-autotrophy was strengthened by terrestrial matter enrichment. In combination with elevated temperature, the terrestrial matter addition effects were intensified, further shifting the size distribution of the microbial food web base from picoplankton to microphytoplankton. These changes up the food web led to increase in the biomass and proportion of large-sized ciliates (>60 µm) and rotifers. Despite the shifts in the microbial food web size structure, grazing experiments suggested that the pathway from picoplankton to nano- and microzooplankton constituted the major energy flow in all treatments. The study implies that the microbial food web compartments in shallow coastal waters will adjust to climate induced increased inputs of terrestrial ma

In this work, the rise characteristics of a single H2 bubble, in the ellipsoidal regime, in (i) water, (ii) single electrolyte (2 M, 4.5 M NaCl) solution and (iii) various concentrations of electrolyte mixture (up to 6.4 M of 1:5 weight fraction NaCl-NaClO3), have been studied, at temperatures up to 80°C. Our results show that both individual and collective effects of the temperature and the electrolyte concentration on the rise velocity and the bubble shape are purely dependent on the changes in liquid properties (density, viscosity, and surface tension); the bubble motion can be described by known non-dimensional correlations for clean bubble rise in pure fluids., ChemE/Transport Phenomena, Executive board

[Introduction]: Human semen analysis must be performed after the liquefaction of the ejaculate. This takes place about 30min after ejaculation and samples must be maintained in the lab during this time. The temperatures for this incubation and the final analysis of motility are crucial but seldom taken into account. This study aims to examine the effect of these temperatures on various sperm parameters both manually (sperm count, motility, morphology, viability, chromatin condensation and maturation and DNA fragmentation) and CASA (kinematics and morphometrics, using an ISAS®v1 CASA-Mot and CASA-Morph systems, respectively) analyzed., [Methods]: Seminal samples from thirteen donors were incubated for 10min at 37°C followed by additional 20min at either room temperature (RT, 23°C) or 37°C and then examined following WHO 2010 criteria., [Results]: The data obtained show that there were no significant differences (P>0.05) in the subjective sperm quality parameters with incubation temperature. On the other hand, the head sperm morphometric parameters were significantly higher after room temperature incubation showing, in addition, lower ellipticity (P<0.05). Furthermore, kinematic parameters were evaluated both at RT and 37°C for the two incubation temperatures. In general, the four temperature combinations showed that kinematic parameters followed this order: RT-RT, [Conclusions]: Our results showed that temperature control during both incubation and analysis is needed for accurate semen analysis, recommending the use of 37°C during the entire process.

African Swine Fever Virus (ASFV) is the cause of an infectious disease in pigs, which is difficult to control. Long viability of ASFV has been shown for several contaminated materials, especially under low temperature. Therefore, when pigs are exposed to a contaminated environment, new infections could occur without the presence of infectious individuals. For example, a contaminated, poorly washed, empty livestock vehicle poses a risk to the next load of pigs. A quantitative stochastic environmental transmission model was applied to simulate the change in environmental contamination levels over time and calculate the epidemic parameters through exposure-based estimation. Due to the lack of experimental data on environmental transmission at low temperatures, we performed a non-linear fit of the decay rate parameter with temperature based on a literature review. Eventually, 16 scenarios were constructed for different temperature (at 20 °C, 10 °C, 0 °C, or −10 °C) and duration of empty periods (1, 3, 5, or 7 days) after the environment had been contaminated. We quantified the variation in the contamination level of the environment over time and the probability of newly added recipients getting infected when exposed to the environment after the empty period. As a result, the transmission rate parameter for ASFV in pigs was estimated to be 1.53 (0.90, 2.45) day-1, the decay rate parameter to be 1.02 (0.73, 1.47) day-1 (at 21 °C), and the excretion rate parameter to be 2.70 (2.51, 3.02) day-1. Without washing and disinfecting, the environment required 9, 14, 24, 54 days to reach a low probability of causing at least one new case (<0.005) at 20 °C, 10 °C, 0 °C, −10 °C, respectively. In addition, the method proposed in this paper enables assessment of the effect of washing and disinfecting on ASFV environmental transmission. We conducted this study to better understand how the viability of ASFV at different temperatures could affect th

CRUE-CSIC (Acuerdos Transformativos 2022), This investigation assesses the effect of the alloy composition and temperature in the corrosivity of the ternary carbonate eutectic, 32% Li2CO3, 33% Na2CO3, 35% K2CO3. To this end, an iron-based alloy, coded as 51Fe-24Cr-20Ni, and a nickel-based alloy, coded as 5Fe–23Cr-58Ni-8Mo, were exposed to the carbonate mixture for 500 h at 700 ºC, 750 ºC and 800 ºC under static atmospheric air. The results revealed that corrosion extension does not have a linear dependence on temperature. There are changes in the corrosion mechanism that depend on the temperature, but, in turn, they are directly influenced by the alloying elements of the material. The performance of the nickel-based substrate proved to be catastrophic at all the studied temperatures. The order from worst to best was 700 ºC > 750 ºC > 800 ºC. The presence of a high molybdenum concentration in the carbonate mixture in contact with this nickel-based alloy suggested that this element dissolution contributes to increasing the corrosivity of the mixture. By contrast, the iron-based alloy showed improved corrosion resistance, with an estimated corrosion rate in the order of hundreds of microns at the three temperatures. The best performance of the 51Fe-24Cr-20Ni alloy was achieved at 700 ºC, followed by that at 800 ºC, while the highest degradation was registered at 750 ºC. This investigation reinforced the idea of the complexity of the corrosion processes in molten carbonate. The equilibrium of corrosive species is very sensitive to an important number of parameters, meaning that modifications in the system conditions have a great impact on corrosivity. Hence, it is critical not to make assumptions when considering potential materials for carbonate containment in CSP technology., Ministerio de Ciencia e Innovación (MICINN), Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

Stellar ejecta gradually enrich the gas out of which subsequent stars form, making the least chemically enriched stellar systems direct fossils of structures formed in the early Universe1. Although a few hundred stars with metal content below 1,000th of the solar iron content are known in the Galaxy2–4, none of them inhabit globular clusters, some of the oldest known stellar structures. These show metal content of at least approximately 0.2% of the solar metallicity ([Fe / H] ≳ − 2.7). This metallicity floor appears universal5,6, and it has been proposed that protogalaxies that merged into the galaxies we observe today were simply not massive enough to form clusters that survived to the present day7. Here we report observations of a stellar stream, C-19, whose metallicity is less than 0.05% of the solar metallicity ([Fe/H]=−3.38±0.06(statistical)±0.20(systematic)). The low metallicity dispersion and the chemical abundances of the C-19 stars show that this stream is the tidal remnant of the most metal-poor globular cluster ever discovered, and is significantly below the purported metallicity floor: clusters with significantly lower metallicities than observed today existed in the past and contributed their stars to the Milky Way halo.

Otoliths, calcified structures in the inner ears, are used to estimate fish age, and their shape is an efficient fish stock identification tool. Otoliths are thus very important for the management and assessment of commercial stocks. However, most studies have used left or right otoliths, chosen arbitrarily without evaluation of the difference between these otoliths. In this study, the asteriscii otoliths from 263 common carp (Cyprinus carpio; Linnaeus, 1758) were sampled in three Iraqi rivers to test the potential asymmetry and the geographical effect on otolith growth from three measurements (length, width and weight), and on shape from two shape indices (ellipticity and form-factor). Among all asteriscii otolith features, there was significant fluctuating asymmetry between fish length and every otolith descriptor. At one fish length, the size and/or the shape of otoliths could be different between two individuals and/or between left and right asteriscii otoliths for the same individual. Moreover, the relationship between fish length and otolith shape/growth was significantly dependent on the studied geographical area and, more especially, the environmental effects as the water temperature and pH. Finally, the relationships between fish length and otolith shape indices showed that the otolith evolves into the elliptical shape during the life of the fish. To use the otolith shape, it is essential to take into account the developmental stage of individuals to integrate the ontogenetic effect. Our results highlight the importance of verifying potential otolith asymmetry, especially for the asteriscii otoliths (lagenar otoliths) before their use in fisheries research.

Otoliths, calcified structures in the inner ears, are used to estimate fish age, and their shape is an efficient fish stock identification tool. Otoliths are thus very important for the management and assessment of commercial stocks. However, most studies have used left or right otoliths, chosen arbitrarily without evaluation of the difference between these otoliths. In this study, the asteriscii otoliths from 263 common carp (Cyprinus carpio; Linnaeus, 1758) were sampled in three Iraqi rivers to test the potential asymmetry and the geographical effect on otolith growth from three measurements (length, width and weight), and on shape from two shape indices (ellipticity and form-factor). Among all asteriscii otolith features, there was significant fluctuating asymmetry between fish length and every otolith descriptor. At one fish length, the size and/or the shape of otoliths could be different between two individuals and/or between left and right asteriscii otoliths for the same individual. Moreover, the relationship between fish length and otolith shape/growth was significantly dependent on the studied geographical area and, more especially, the environmental effects as the water temperature and pH. Finally, the relationships between fish length and otolith shape indices showed that the otolith evolves into the elliptical shape during the life of the fish. To use the otolith shape, it is essential to take into account the developmental stage of individuals to integrate the ontogenetic effect. Our results highlight the importance of verifying potential otolith asymmetry, especially for the asteriscii otoliths (lagenar otoliths) before their use in fisheries research.

Bicycles are becoming always more popular as a cheap and healthy tool for urban travels. The concerns für crowded public transport means are changing the habits after the pandemic situation caused by Covid-19, encomaging people towards the use of bicycle. As stated in literature, tyres play a large role in the handling ofbicycles . This is why it is necessary to characterize tyres so as to derive useful parameters for modeling. To this purpose, proper experimental methods have been implemented for bicycle tyres. A deepen knowledge of the phenomena occurring at tyre/road contact patch is indeed fundamental to ensure proper adherence and safety conditions, especiatly for vehicles as bicycles or motorcycles working with high camber angles. This paper aims at enabling the future development of bicycle tyres, in order to improve the safety and the performances. Specifically, the focus is devoted to understand how the road temperature can impact on tyre performances, and therefore on bicycle handling. After a brief section describing the methods and instruments used für this research activity, the results of an experimental campaign carried out on road racing tyre are presented and discussed. The remarkable variation of temperature oftyre rolling surface can have multiple impacts on the performances. lt can affect the noise emissions as weil as rolling resistance, as noted in, where higher temperature was co.rrelated to lower rolling resistance coefficient. In the temperatu.re influence on car tyre lateral characteristics is investigated on a drum testrig. A They found a decrease in cornering stiffness as temperature increases, while no particular variations on relaxation length were observed. Despite the known influence of the temperature on tyre properties, there is a lack of studies regarding bicycle tyres. In a test on testrig of wintertype tyre revealed remarkable differences with respect to the mechanical characteristics of other tyres tested at room temperature. Th, Biomechatronics & Human-Machine Control

Interpreting the subtleness and complexity of vulnerable road user (VRU) behaviour is still a significant challenge for automated vehicles (AVs). Solutions for facilitating safe and acceptable interactions in future automated traffic include equipping AVs and VRUs with human-machine interfaces (HMl.s), such as awareness and notification systems, and connecting road users to a network of A Vs and infrastructure. The research on these solutions, however, primarily focuses on pedestrians. There is no overview ofthe type of systems or solutions supporting cyclists in future automated traffic. The objective ofthe present study is to synthesise current literature and provide an overview ofthe state-ofthe-art support systems available to cyclists. The aim is to identify, classify, and count the types of communicative technologies, systems, and devices capable of supporting the safety of cyclists in automated traffic. The overall goal is to understand A V-cyclist interaction better, pinpoint knowledge gaps in current literature, and develop strategies for optimising safe and pleasant cycling in future traffic environments with AVs., Transport and Planning, Human-Robot Interaction

This study provides an alternative solution to the improvement on solid–liquid phase change by designing a Y-shaped fin in a nonuniform pattern along the gravity direction. A numerical model is established and validated through the present measurement and data in literature. Six cases with different Y-shaped fins and locations are designed and compared to the original straight fin case. Thermal assessments on the melting fraction, temperature field, velocity distribution, and uniformity for melting are made. Results demonstrate that the nonuniform melting features caused by the local natural convection are significantly eliminated by the novel nonuniform fin structure. The time required for melting the lower PCM is found to occupy more than 50% of the completely melting time. The accurate local heat transfer enhancement measures (bottom enhancement) are conducive to markedly reduce the full melting time by 21.5%, compared to the uniform fin pattern. Upon using finned thermal storage tank for a mobilized thermal storage truck (bare tube tank), the initial investment increases by 44.9% but the profit increases by 393.6% and the payback period reduces by 69.2%. The use of fin tube in heat storage tank can quickly obtain higher returns based on a small increase in initial investment. This work provides new insights into the understandings of the transient phase change process and the strategies for guiding the design for thermal energy storage tank.

Quantifying rock weathering processes, especially in ways of nondisturbance and on-site investigation, is one of the most critical tasks in predicting rocks erosion rates and understanding the sediment transportation. We proposed a more reproducible approach to test how image analysis can quantify the changes in the size and shape of fragments during the weathering process. Four artificial models were designed to select suitable metrics among over 20 parameters. To validate the efficiency of image analysis, we analyzed rocks from badlands in Nanxiong Basin, Southeast China, under three different ranges of temperature differences (TD) during cyclic wetting and drying (WD). Our results show that TDs can accelerate the disintegration rate, and even if there is only a 20°C difference in the range of TDs, an apparent difference in fragment size was observed. Moreover, the shape of fragments became more round as the increasing number of cyclic treatments, and for samples that went through the same number of treatments, the larger the temperature difference, the more round the shape became. All that serves as another evidence for landscape evolution response to climatic warming.

Arctic vegetation cover has been increasing over the last 40 years, which has been attributed mostly to increases in temperature. Yet, the temporal dimension of this greening remains overlooked as it is often viewed as a monotonic trend. Here, using 11 year long rolling windows on 30 m resolution Landsat data, we examined the temporal variations in greening in north-eastern Canada and its dependence on summer warming. We found two significant and distinct waves of greening, centred around 1996 and 2011, and observed in all land cover types (from boreal forest to arctic tundra). The first wave was more intense and correlated with increasing summer temperature while no such relation was found for the weaker second wave. More specifically, the greening lasted longer at higher elevation during the first wave which translates to a prolonged correlation between greening and summer warming compared to low-altitude vegetation. Our work explored a forsaken complexity of high latitude greening trends and associated drivers and has raised new questions that warrant further research highlighting the importance to include temporal dimension to greening analyses in conjunction with common spatial gradients.

A first-principles based modeling approach to the effect of temperature on the isothermal single-crystal and polycrystalline elastic parameters of Fe-rich solid solutions is reported. The approach integrates alloy theory for chemical and magnetic disorders with accessible experimental data for the equilibrium volume and ferromagnetic phase transition, and is adopted to predict the temperature-dependent elastic parameters of the body-centered cubic phase of three reduced activation steels, CLAM/CLF-1, F82H, EUROFER97, considered as high-temperature material in power reactors. The predictions are assessed based on available experimental data for a reduced activation steel and both experimental and theoretical data for pure Fe. Alloying effects on the elastic constants relative to pure Fe are found to differ in the magnetically ordered and disordered phases. Contributions due to loss of long-range magnetic order, volume expansion, and entropy are important in determining the temperature dependence of the elastic parameters in all investigated materials. A previously reported, peculiar magneto-volume phenomenon on the equation of state in pure Fe is gradually removed by alloying and magnetic disordering, which requires particular attention when describing the thermo-chemical effects derived from the equation of state in Fe-rich solid solutions.

A first-principles based modeling approach to the effect of temperature on the isothermal single-crystal and polycrystalline elastic parameters of Fe-rich solid solutions is reported. The approach integrates alloy theory for chemical and magnetic disorders with accessible experimental data for the equilibrium volume and ferromagnetic phase transition, and is adopted to predict the temperature-dependent elastic parameters of the body-centered cubic phase of three reduced activation steels, CLAM/CLF-1, F82H, EUROFER97, considered as high-temperature material in power reactors. The predictions are assessed based on available experimental data for a reduced activation steel and both experimental and theoretical data for pure Fe. Alloying effects on the elastic constants relative to pure Fe are found to differ in the magnetically ordered and disordered phases. Contributions due to loss of long-range magnetic order, volume expansion, and entropy are important in determining the temperature dependence of the elastic parameters in all investigated materials. A previously reported, peculiar magneto-volume phenomenon on the equation of state in pure Fe is gradually removed by alloying and magnetic disordering, which requires particular attention when describing the thermo-chemical effects derived from the equation of state in Fe-rich solid solutions., QC 20210112

A first-principles based modeling approach to the effect of temperature on the isothermal single-crystal and polycrystalline elastic parameters of Fe-rich solid solutions is reported. The approach integrates alloy theory for chemical and magnetic disorders with accessible experimental data for the equilibrium volume and ferromagnetic phase transition, and is adopted to predict the temperature-dependent elastic parameters of the body-centered cubic phase of three reduced activation steels, CLAM/CLF-1, F82H, EUROFER97, considered as high-temperature material in power reactors. The predictions are assessed based on available experimental data for a reduced activation steel and both experimental and theoretical data for pure Fe. Alloying effects on the elastic constants relative to pure Fe are found to differ in the magnetically ordered and disordered phases. Contributions due to loss of long-range magnetic order, volume expansion, and entropy are important in determining the temperature dependence of the elastic parameters in all investigated materials. A previously reported, peculiar magneto-volume phenomenon on the equation of state in pure Fe is gradually removed by alloying and magnetic disordering, which requires particular attention when describing the thermo-chemical effects derived from the equation of state in Fe-rich solid solutions.

A first-principles based modeling approach to the effect of temperature on the isothermal single-crystal and polycrystalline elastic parameters of Fe-rich solid solutions is reported. The approach integrates alloy theory for chemical and magnetic disorders with accessible experimental data for the equilibrium volume and ferromagnetic phase transition, and is adopted to predict the temperature-dependent elastic parameters of the body-centered cubic phase of three reduced activation steels, CLAM/CLF-1, F82H, EUROFER97, considered as high-temperature material in power reactors. The predictions are assessed based on available experimental data for a reduced activation steel and both experimental and theoretical data for pure Fe. Alloying effects on the elastic constants relative to pure Fe are found to differ in the magnetically ordered and disordered phases. Contributions due to loss of long-range magnetic order, volume expansion, and entropy are important in determining the temperature dependence of the elastic parameters in all investigated materials. A previously reported, peculiar magneto-volume phenomenon on the equation of state in pure Fe is gradually removed by alloying and magnetic disordering, which requires particular attention when describing the thermo-chemical effects derived from the equation of state in Fe-rich solid solutions.

Aim: The Expansion-Contraction model has been used to explain the responses of species to climatic changes. During periods of unfavourable climatic conditions, species retreat to refugia from where they may later expand. This paper focuses on the palaeoecology of red deer over the past 54 ka across Europe and the Urals, to reveal patterns of change in their range and explore the role of environmental conditions in determining their distribution. Location: Europe and western Asia to 63°E. Taxon: Red deer (Cervus elaphus). Methods: We collected 984 records of radiocarbon-dated red deer subfossils from the Late Pleistocene and the Holocene, including 93 original dates. For each deer sample we compiled climatic and biome type data for the corresponding time intervals. Results: During the last 54 ka changes in red deer range in Europe and the Urals were asynchronous and differed between western and eastern Europe and western Asia due to different environmental conditions in those regions. The range of suitable areas for deer during the Last Glacial Maximum (LGM) was larger than previously thought and covered vast regions not only in southern but also in western and eastern Europe. Throughout the period investigated the majority of specimens inhabited forests in the temperate climatic zone. The contribution of forests in deer localities significantly decreased during the last 4 ka, due to deforestation of Europe caused by humans. Mean January temperature was the main limiting factor for species distribution. Over 90% of the samples were found in areas where mean January temperature was above −10°C. Main conclusions: Red deer response to climatic oscillations are in agreement with the Expansion-Contraction model but in contradiction to the statement of only the southernmost LGM refugia of the species. During the last 54 ka red deer occurred mostly in forests of the temperate climatic zone. © 2020 John Wiley & Sons Ltd.

Structural Health Monitoring (SHM) systems have been heavily studied worldwide in the past decades. In this field, extensive research has been carried out on vibration-based damage detection (VBDD) techniques in civil structures, especially in bridges. Dynamic responses of a structure manifest a certain degree of sensitivity not only to structural damage but also to any change in operational and environmental conditions, these last factors can mask structural damages. In this sense, the main objective of this paper is to separate structural damage conditions from the changes caused by the environmental effects in a numerical benchmark bridge structure. Temperature is chosen as a global environmental parameter for its significant impact on the waveform, and the Instantaneous Phase Difference (IPD) obtained from an analysis of the Hilbert spectral is studied as the vibration damage feature. Principal Component Analysis (PCA) is applied mainly to the IPD in order to eliminate the environmental influence. Due to the lack of experimental data including the temperature effects, the effectiveness and robustness of the proposed procedure is applied to a numerical benchmark bridge structure generated as part of COST Action TU1402 on quantifying the value of information (VoI) in SHM. The benchmark model consisted of a two-span steel bridge under operational (vehicular traffic) and environmental variability, in which two levels of damage were introduced. The dynamic responses in both healthy and structural damage conditions were obtained from a nonlinear time-history analysis using an open access Python code. As the main concluding remark, the suitability of Hilbert-Huang Transform combined with a PCA-based approach and the instantaneous phase difference to achieve a more robust damage assessment algorithm is verified for the numerical benchmark bridge., The second author wishes to express their gratitude for the financial support received from PRONABEC Program of Peruvian Ministry of Education with the President of the Republic Scholarship for the great support on his PhD studies. The authors wish to thank the Prof. Eleni Chatzi, ETH Zurich, for their valuable sharing of the entire data from numerical benchmark bridge used in the present research. Authors are indebted to the Secretaria d’ Universitats i Recerca de la Generalitat de Catalunya for the funding provided through AGAUR (2017 SGR 1481)., Postprint (author's final draft)

A new model is proposed for describing freeze-thaw-induced plastic volume changes in saturated clays based on microscopic inhomogeneities inherent in the soil structure and the pore water transfer between them. It is shown through a simple inhomogeneous mesostructure model that the equilibrium state reached after freezing serves as an important reference state for interpreting the volumetric behaviour. The soil state evolution towards this freeze equilibrium state describes many features seen in the experimentally observed freeze-thaw behaviour, such as the existence of a limiting stress level above which no plastic volume change occurs. The process of freezing/thawing is modelled as a rate process approaching the freeze equilibrium line (FEL) and representing the eventual equilibrium states at a particular sub-freezing temperature, exploiting a newly defined state parameter, psi(fe). The model offers a mesoscopic three-dimensional yield surface in the specific volume - effective stress - temperature space, expressed by a simple equation. Although the model's essence is encapsulated in only two simple equations, it can simulate well the experimentally observed volume change accumulation with freeze-thaw cycles under different stress levels and densities (or over-consolidation ratios). As the model is formulated in an incremental rate form, it can be applied to general freeze-thaw problems, even those with irregular temperature and stress history - a feature not seen in existing models. (C) 2021 Production and hosting by Elsevier B.V. on behalf of The Japanese Geotechnical Society.

A first-principles based modeling approach to the effect of temperature on the isothermal single-crystal and polycrystalline elastic parameters of Fe-rich solid solutions is reported. The approach integrates alloy theory for chemical and magnetic disorders with accessible experimental data for the equilibrium volume and ferromagnetic phase transition, and is adopted to predict the temperature-dependent elastic parameters of the body-centered cubic phase of three reduced activation steels, CLAM/CLF-1, F82H, EUROFER97, considered as high-temperature material in power reactors. The predictions are assessed based on available experimental data for a reduced activation steel and both experimental and theoretical data for pure Fe. Alloying effects on the elastic constants relative to pure Fe are found to differ in the magnetically ordered and disordered phases. Contributions due to loss of long-range magnetic order, volume expansion, and entropy are important in determining the temperature dependence of the elastic parameters in all investigated materials. A previously reported, peculiar magneto-volume phenomenon on the equation of state in pure Fe is gradually removed by alloying and magnetic disordering, which requires particular attention when describing the thermo-chemical effects derived from the equation of state in Fe-rich solid solutions.

A new model is proposed for describing freeze-thaw-induced plastic volume changes in saturated clays based on microscopic inhomogeneities inherent in the soil structure and the pore water transfer between them. It is shown through a simple inhomogeneous mesostructure model that the equilibrium state reached after freezing serves as an important reference state for interpreting the volumetric behaviour. The soil state evolution towards this freeze equilibrium state describes many features seen in the experimentally observed freeze-thaw behaviour, such as the existence of a limiting stress level above which no plastic volume change occurs. The process of freezing/thawing is modelled as a rate process approaching the freeze equilibrium line (FEL) and representing the eventual equilibrium states at a particular sub-freezing temperature, exploiting a newly defined state parameter, psi(fe). The model offers a mesoscopic three-dimensional yield surface in the specific volume - effective stress - temperature space, expressed by a simple equation. Although the model's essence is encapsulated in only two simple equations, it can simulate well the experimentally observed volume change accumulation with freeze-thaw cycles under different stress levels and densities (or over-consolidation ratios). As the model is formulated in an incremental rate form, it can be applied to general freeze-thaw problems, even those with irregular temperature and stress history - a feature not seen in existing models. (C) 2021 Production and hosting by Elsevier B.V. on behalf of The Japanese Geotechnical Society.

The final authenticated version is available online at https://doi.org/10.1007/978-3-030-91877-4_22., Monitoring structural damage is widely used for sustaining and preserving the service life in civil structures, especially in bridges. The influence of environmental variability like temperature affects the dynamic behavior, which can mask subtler structural changes caused by damage. The direct application of vibration-based damage detection methods to measured responses without a prior treatment of the ambient data may lead to false condition assessments. In this article, the main objective is to separate the structural damage conditions from the changes caused by the environmental effects in a numerical benchmark bridge. The Principal Component Analysis (PCA) is applied to decide if the change in vibration characteristics is due to environmental effects or structural damages. The proposed approach in the use of PCA not only allows to detect the damage without the requirement of the baseline to consist of damage sensitivity features obtained from a wide range of environmental conditions, but also serves as a measure for its quantification. The effectiveness and robustness of the proposed methodology is applied to a benchmark bridge structure generated as part of COST Action TU1402 on quantifying the value of information (VoI) in SHM. The benchmark model consisted of a two-span steel bridge under environmental effects, in which two levels of damage were introduced., Peer Reviewed, Postprint (author's final draft)

High temperature (HT) and drought (D) have detrimental effects on growth and phenology that result in reductions of the yields of agricultural crops. Nevertheless, homeostatic ranges of tolerance exist. Recent analysis of survey data and simulations suggest US wheat (Triticum aestivum L.) yields remain relatively stable under irrigation in the range of 35°– 40°C. Applying analogue statistical procedures on experimental data and simulations from the Hot Serial Cereal Experiment (HSC) we demonstrate that failed incorporation of the corresponding phenological acceleration due to HT and a low interannual temperature variability lead to this result. Here, we incorporate the phenological effect into the used binned temperature exposure yield model by rescaling (normalizing) the absolute seasonal temperature counts to a maximum season length. The application to observed and simulated HSC data with a wide temperature range reveals that the suggested upper homeostatic response limit of US wheat yields to HT requires a down–revision. HT stress can be reduced by transpirational cooling. However, the effect is currently not sufficient to expand the homeostatic range of irrigated wheat markedly beyond 25°C taking our analysis of the HSC experiment.

A first-principles based modeling approach to the effect of temperature on the isothermal single-crystal and polycrystalline elastic parameters of Fe-rich solid solutions is reported. The approach integrates alloy theory for chemical and magnetic disorders with accessible experimental data for the equilibrium volume and ferromagnetic phase transition, and is adopted to predict the temperature-dependent elastic parameters of the body-centered cubic phase of three reduced activation steels, CLAM/CLF-1, F82H, EUROFER97, considered as high-temperature material in power reactors. The predictions are assessed based on available experimental data for a reduced activation steel and both experimental and theoretical data for pure Fe. Alloying effects on the elastic constants relative to pure Fe are found to differ in the magnetically ordered and disordered phases. Contributions due to loss of long-range magnetic order, volume expansion, and entropy are important in determining the temperature dependence of the elastic parameters in all investigated materials. A previously reported, peculiar magneto-volume phenomenon on the equation of state in pure Fe is gradually removed by alloying and magnetic disordering, which requires particular attention when describing the thermo-chemical effects derived from the equation of state in Fe-rich solid solutions.

In previous works, the authors have shown the feasibility of using classical and robust principal component analysis for damage detection on structures when ultrasonic guided waves are used. It has also been demonstrated that robust principal component analysis presents a higher probability of detection accuracy when data are corrupted. In the present work, a robust principal component analysis orthogonal distance is proposed as a new feature for damage detection strategy based on ultrasonic guided waves on structures subjected to uniform temperature changes. The effect of this temperature fluctuation on the signal propagation and also in the new feature is analyzed. Temperature compensation is applied to mitigate the effect of temperature changes on the reliability of the damage detection methodology. The proposed feature and damage detection strategy that considers these effects are tested on two structures: a laboratory scale composite plate and a large-scale complex composite that is representative of a component from an aerospace application. The promising result proves the ability of the new feature as a damage detection tool.

Power generation processes generate wastewater that is rich in scale-forming agents and which, therefore, requires suitable pre-treatment prior to further treatment with an RO system. In this study, Rheofloc5023 was used as a coagulant, while Rheofloc5414, ARFloc100, and Genefloc were the selected flocculants applied after the pH adjustment with lime and NaOH to alter the solubility of the ions in the water. The tests were conducted at 40°C and 60°C to observe the effect that temperature has on the treatment process. Four parameters were considered during the optimization process, namely, conductivity, turbidity, total hardness, and alkalinity. When lime was used, it was found that the treatment was superior at 60°C with ARfloc100 as flocculant. A coagulant dosage of 0.5 mg/L, a flocculant dosage of 0.2 mg/L, and a lime dosage of 220 mg/L were found to be optimal for a conductivity removal of 36%, a turbidity increase of 59%, a total hardness removal of 54%, and an alkalinity removal of 71%. When NaOH was used, Rheofloc5414 at 40°C was found to be optimal with coagulant and flocculant dosages of 5 and 0.5 mg/L, respectively. This yielded a conductivity removal of 1.26%, a turbidity removal of 58.75%, a total hardness removal of 20.3%, and an alkalinity removal of 50.6%. Thus, lime treatment was more efficient for the removal of scaling agents from the water. However, it was found that settling occurred faster at 60°C with both lime and NaOH and that the latter had a better settling velocity characterized by the formation of more stable crystals. This finding was confirmed with a scanning electron microscopy, as the treatment with NaOH and Rheofloc5414 at 60°C had larger and more densely packed crystals. From the above findings, it is suggested that lime should be used for treatment, as it removed more scaling agents and it is less expensive and more readily available than NaOH

We are facing an important challenge, to reduce the greenhouse gas emissions to make sure that we limit global warming to 2 °C, preferably 1.5 °C. Drastic changes and developing new methods may be our only chance to keep global warming under 1.5 °C. The steel production in Sweden today accounts for 10% of the CO2 emission. The joint venture HYBRIT (Hydrogen Breakthrough Ironmaking Technology), between SSAB, LKAB and Vattenfall, aims to reduce the CO2 emission by developing a method that reduces iron ore pellets with hydrogen gas, leaving only water as off-gas. From simple thermodynamic calculations, it is evident that the reduction of iron ore using hydrogen gas is an endothermic reaction, requiring heat. Based on the calculated energy requirement, the temperature at the center of the pellet should not be the same as the temperature at the surface of the pellet but instead, decrease as the reduction reaction takes place. This report presents the temperature profile at the surface and in the center of a hematite pellet during hydrogen reduction at temperatures of 600 °C, 700 °C, 800 °C and 900 °C. Ideally, the results can be implemented in a model to better simulate the reduction reaction taking place inside a hematite pellet. The experiment consists of three sub-experiments, the first measures the temperature profile of the unreduced iron ore pellet in an argon gas atmosphere, secondly, the temperature profile and mass loss are measured during reduction, lastly, the temperature profile is measured for the reduced pellet in a hydrogen atmosphere. The mass loss measured during hydrogen reduction is used to calculate the degree of reduction. The results show that the reaction rate increases with increasing temperature and concentration of H2. Additionally, a higher reduction temperature gives the largest temperature decrease inside the pellet during reduction. At 900 °C, the temperature decrease is equal to 39 °C and at 600 °C, it is equal to 3 °C. The results prove th, Idag står vi inför en viktig utmaning, att minska utsläppen av växthusgaser och se till så att vi inte överskrider 2 °C uppvärmning, helst inte 1.5 °C. För att klara detta krävs drastiska förändringar och utvecklingar av nya metoder kan vara vår enda chans att uppnå 1.5-gradersmålet. Ståltillverkningen i Sverige idag står för 10% av CO2 utsläppen och för att bidra till att minska utsläppen av CO2 har företaget HYBRIT, vilket står för Hydrogen Brakethrough Ironmaking Technology, skapats. HYBRIT är en joint venture mellan SSAB, LKAB och Vattenfall som tillsammans vill skapa stål på ett mer miljövänligt sätt. Processen går ut på att reducera järnmalmspellets med hjälp av vätgas för att producera järnsvamp och ge ifrån sig vatten som avgas. Från enkla termodynamiska beräkningar är det lätt att inse att reduktionen med hjälp av vätgas är en endoterm process, som kräver energi. Det är genom denna kunskap som en kan föreställa sig att reduktionen av järnmalmspellets med hjälp av vätgas kommer bidra till en temperaturminskning. I denna rapport har temperaturprofilen inne i och på ytan av en hematitpellet mätts under tiden som den blivit reducerad med vätgas. Idealt kan resultaten implementeras i en modell för att bättre simulera reduktionsreaktionen som äger rum i en hematitpellets. Fyra olika reduktionstemperaturer har undersökts: 600 °C, 700 °C, 800 °C och 900 °C. Experimenten består av tre del-experiment, först mäts temperaturprofilen av den oreducerad hematitpelletsen i en argonatmosfär, sedan mäts viktminskningen och temperaturprofilen av pelleten medan den reduceras i en vätgasatmosfär, slutligen mäts temperaturprofilen av den reducerade pelleten i en argonatmosfär. Viktminskningen under reduktionen används för att beräkna reduktionsgraden under reduktionsförloppet. Resultaten visade att reduktionshastigheten ökade med ökande temperatur och koncentration av H2. Ökad temperatur gav även den största temperaturminskningen inne i pelleten då den reducerats med vätgas. Vid

Power generation processes generate wastewater that is rich in scale-forming agents and which, therefore, requires suitable pre-treatment prior to further treatment with an RO system. In this study, Rheofloc5023 was used as a coagulant, while Rheofloc5414, ARFloc100, and Genefloc were the selected flocculants applied after the pH adjustment with lime and NaOH to alter the solubility of the ions in the water. The tests were conducted at 40°C and 60°C to observe the effect that temperature has on the treatment process. Four parameters were considered during the optimization process, namely, conductivity, turbidity, total hardness, and alkalinity. When lime was used, it was found that the treatment was superior at 60°C with ARfloc100 as flocculant. A coagulant dosage of 0.5 mg/L, a flocculant dosage of 0.2 mg/L, and a lime dosage of 220 mg/L were found to be optimal for a conductivity removal of 36%, a turbidity increase of 59%, a total hardness removal of 54%, and an alkalinity removal of 71%. When NaOH was used, Rheofloc5414 at 40°C was found to be optimal with coagulant and flocculant dosages of 5 and 0.5 mg/L, respectively. This yielded a conductivity removal of 1.26%, a turbidity removal of 58.75%, a total hardness removal of 20.3%, and an alkalinity removal of 50.6%. Thus, lime treatment was more efficient for the removal of scaling agents from the water. However, it was found that settling occurred faster at 60°C with both lime and NaOH and that the latter had a better settling velocity characterized by the formation of more stable crystals. This finding was confirmed with a scanning electron microscopy, as the treatment with NaOH and Rheofloc5414 at 60°C had larger and more densely packed crystals. From the above findings, it is suggested that lime should be used for treatment, as it removed more scaling agents and it is less expensive and more readily available than NaOH