Increased Mass Loss Research Articles

Enhanced Anti-Corrosion and Biological Performance of Plasma-Sprayed Nb/ZrO2/HA Coatings on ZK60 Mg Alloy

Niobium (Nb) and zirconium dioxide (ZrO2) were doped into hydroxyapatite (HA) to fabricate HA-based composite coatings prepared on a ZK60 magnesium alloy by plasma spraying technology to improve anti-corrosion and biocompatibility for clinical applications. The results revealed that the Nb-enriched coating exhibits fewer cracks and pores with a flat surface due to the decreased temperature gradient during spraying, and small needle-like structures can fill the cracks and pores in the ZrO2-contained coating, resulting in a more uniform and dense surface. Compared to coatings with only niobium or zirconium dioxide, the ZrO2/Nb/HA composite coating significantly enhanced the mechanical properties and corrosion resistance of the magnesium alloys. Among all the specimens, the ZrO2/HA coating and ZrO2/Nb/HA coating revealed high surface hardness values (327.73 HV and 293.80 HV, respectively). However, the higher hardness value made the ZrO2/HA coating fragile and more likely to crack, while the ZrO2/Nb/HA coating avoided this shortcoming and exhibited a more comprehensive performance. During immersion tests, the ZrO2/Nb/HA coating exhibited a gradual pH increase and minimal mass loss, and the cytocompatibility test demonstrated promising cellular activity.

Thermomechanical response and crack evolution of sandstone at elevated temperatures

Understanding the thermomechanical response of rock at high temperatures is crucial for various energy applications such as underground coal gasification and geothermal systems. The study investigated the effects of temperature, mineral composition, and grain size on crack initiation (CI) and crack damage (CD) thresholds in Jodhpur sandstones using uniaxial compressive strength with acoustic emission, Brazilian tensile strength, and thermogravimetric analysis subjected to elevated temperatures. The study revealed distinct patterns in crack initiation stress threshold ratios (CISTR) and crack damage stress threshold ratios (CDSTR) influenced by mineral composition and grain size under temperature treatments. Ferruginous quartz arenite exhibited an inverse relationship between quartz content and crack initiation/damage stress thresholds, while siliceous quartz arenite and subarkose showed a positive correlation. The established variation is attributed to the differing grain boundary strengths among the minerals. Comparative analysis of crack thresholds with the minerals, excluding quartz and feldspar, revealed complex relationships with clay and other minerals. Finer-grained sandstones showed direct proportionality in CI and CISTR with clay content, while coarser sandstones exhibited an inverse relationship. Additionally, the study highlighted differential trends in toughness parameters and CISTR, emphasizing the role of grain size and heat-treatment conditions in governing stress thresholds. Significant chemical changes, including quartz phase shifts and kaolinite/muscovite dehydroxylation, occurred in sandstones at 500–600°C. The presence of kaolinite/hematite in ferruginous quartz arenite caused the increased mass loss in pure O2 due to kaolinite breakdown, while siliceous quartz arenite exhibited a greater mass loss in standard conditions. The findings suggest that quartz content does not consistently enhance rock strength under heat treatment, particularly in the presence of significant clay minerals, leading to an inverse quartz-rock strength relationship in ferruginous quartz arenites. The study provides valuable insights into the thermomechanical behavior of sandstones, which is crucial for assessing rock stability and durability in energy applications.

Effects of aggregates and fibers on the strength and permeability of concrete exposed to low vacuum environment

The performance and regulation of concrete in low vacuum environments are receiving increasing attention. This study investigates the effects of aggregates and fibers on the strength and permeability of concrete in a low vacuum environment, using varying gradients of sand ratios (37.5 %, 40 %, and 42 %) and aggregate-to-binder ratios (3.27, 3.92, and 4.14). Three types of non-metallic fibers are utilized: polyethylene (PE), polyvinyl alcohol (PVA), and glass fibers. Evaluations focus on concrete strength, mass loss, gas permeability, capillary water absorption, and porosity. Results indicate that higher sand and aggregate-to-binder ratios enhance both flexural and compressive strength. Fiber incorporation improves flexural and compressive toughness, with PE fibers showing the most significant toughening effect. The low vacuum environment increases the strength of the concrete but reduces its axial compression toughness ratio and increases brittleness, while fiber incorporation helps improve the compression toughness of the concrete. Higher sand and aggregate-to-binder ratios reduce mass loss and accelerate drying equilibrium, while fibers increase mass loss and prolong drying equilibrium, with PVA fibers causing greater mass loss. The pattern of concrete mass loss can be explained by the tortuosity of the moisture diffusion path. Additionally, low vacuum significantly increases the gas permeability of concrete. Enhancing the sand and aggregate-to-binder ratios reduces permeability both before and after low vacuum treatment. Although fibers increase the gas permeability, they help mitigate this increase under low vacuum condition. Capillary water absorption tests reveal that concrete under low vacuum condition has a significantly higher water absorption rate compared to air-drying condition. Increasing sand and aggregate-to-binder ratios reduces water absorption and capillary water content, whereas fibers have the opposite effect. Porosity tests show that moisture migration in a low vacuum environment is mainly related to permeable porosity, while total porosity is more closely related to compressive strength.

Mechanical properties and damage constitutive model of concrete containing waste glass and rice husk ash in high-temperature environments

The application of waste glass and rice husk ash in concrete promotes sustainable development by reducing resource consumption and environmental pollution. This study evaluates the high-temperature performance of concrete containing glass sand, glass powder, and rice husk ash. Results show that waste glass increases mass loss, while rice husk ash reduces it and enhances concrete compactness. At ambient temperature, compressive strength is lower in rice husk ash samples compared to waste glass concrete, but higher at elevated temperatures. Particle size differences between glass sand and glass powder mainly influence high-temperature performance. Waste glass does not significantly mitigate cyclic loading damage, whereas rice husk ash reduces damage in glass sand concrete but not in glass powder concrete. A uniaxial compression thermo-mechanical coupling damage model and an improved Broutman-Hull cyclic compression damage model are established, providing a basis for the design and safety evaluation of concrete structures in high-temperature environments.

Extraction and Physicochemical Characterization of Hydroxyapatites From Horse Humerus Bones of Different Ages (1, 3, 6, and 8 Years old) Calcined at Low Temperature.

The aim of this work is to investigate the changes in the physicochemical properties of hydroxyapatite (HAp) extracted from horse humerus bones of different ages (1, 3, 6, and 8 years) subjected to low temperature calcination (600°C). Thermal analysis revealed significant mass loss due to water, collagen, organic compounds, carbonates, and age-related magnesium out-diffusion. Higher fat content in older bones contributed to increased mass loss. Phosphorus content remained constant across age groups, while calcium and sodium showed age-related fluctuations. Magnesium levels decreased with age, emphasizing its importance for early bone development. The Ca/P ratio deviated from the stoichiometric values due to additional ions from biogenic sources. Infrared spectroscopy identified functional groups in carbonated HAp, with changes observed before and after calcination. The full width at half maximum (FWHM) of the 961 cm-1 band decreased with age, indicating improved crystalline quality. The molar absorption coefficients provided information on the changes in molecular concentration and emphasized the differences between the age groups. X-ray analysis revealed nanocrystalline HAp in all samples, with crystallite size increasing with age. Rietveld analysis showed that the lattice parameters were affected by the presence of organic material, but the lattice constants remained stable, confirming high crystallinity independent of age. TEM analysis confirmed nanocrystalline structures, with crystallite size increasing with age. SEM images showed the characteristic porosity of calcined HAp, with particle size correlating positively with age. Calcination at 600°C preserved the nanoscale properties and microcrystal formation. Raman spectroscopy confirmed the identity of HAp, with FWHM variations indicating age-related changes in crystalline quality. EHAp1 showed increased FWHM, indicating lower crystalline quality and increased trace element content.

Bending performance of lightweight aggregate concrete beam subjected to reinforcement corrosion: Experimental and numerical study

The application of lightweight aggregate concrete (LWAC) benefits the structural behavior of long-span and high-rise buildings. However, the corrosion-related durability issue of bending elements made of LWAC has remained unresolved for decades, and the bending performance of corroded LWAC beam, including load-bearing capacity, stiffness, cracking, and etc., has not yet been clearly defined due to limited knowledge in the available literature. This study aims to investigate the bending performance of LWAC beams subjected to reinforcement corrosion, and the test results provide valuable data for addressing the research gap relevant to the topic and contribute fundamental knowledge to the promotion of structural LWAC elements. Seven reinforced LWAC beams were tested to examine the cracking behavior, characteristic loads and deflections, deformation ability, and distribution of cross section strain at various moments. The modelling method considering the effect of rebar corrosion for LWAC beam was proposed. It was concluded that the corrosion of longitudinal rebar led to decreased cracking, yielding, and ultimate moment of LWAC beam, while the corrosion of stirrups increased the cracking moment and had little effects on the yielding and ultimate moments. The ductility of the tested specimens initially decreased and then increased with the raising corrosion level of the longitudinal rebar, which was attributed to the variation in bond performance between the rebar and LWAC. All tested beams exhibited a yielding deflection smaller than 1/235 of the span length. The strain distribution of the mid-span cross-section exhibited a nonlinear feature with increasing mass loss of the corroded longitudinal steel rebar. The proposed modelling procedure considering the corrosion effect showed good agreement with the test results, and a preliminary analysis of the bending performance of LWAC beams with different steel reinforcement corrosion ratios was completed. Data Availability StatementAll data, models, or code that support the findings of this study are available from the corresponding author upon reasonable request.

Digital replica to unveil the impact of growing conditions on orange postharvest quality

The postharvest end-quality of citrus is significantly impacted by pre-harvest factors such as weather, which varies among growing regions. Despite the importance of these factors, the influence of regional weather variations, such as variations in temperature, humidity, wind, vapor pressure deficit (VPD), and solar radiation on postharvest citrus quality, is largely unknown. This study aims to quantify this impact through a physics-driven digital replica of the entire value chain of Valencia oranges, from orchards in South Africa to retail in Europe. Predicted fruit properties data at harvest and hygrothermal sensor data from orchard to retail for different production regions are coupled to a physics-based fruit model to simulate key postharvest fruit quality metrics. These metrics include mass loss, chilling injury, fruit quality index (FQI), remaining shelf life (RSL), total soluble solids (TSS), and titratable acidity (TA). Our digital fruit model reveals that regional weather variability significantly affects fruit quality evolution when comparing data from Nelspruit, Letsitele, and Sunday’s River Valley (SRV). The impact of weather variations is most pronounced in the temperate oceanic climate of SRV compared to the hotter climates of Letsitele and Nelspruit. Our findings indicate that differences in weather conditions between these growing regions impact postharvest mass loss, FQI, RSL, TSS, and TA of Valencia oranges at retail. The impact is up to 10% variation in mass loss and RSL, 4% in TSS, and 1% in TA among oranges grown in different regions. We show that temperature and humidity variations in the postharvest local transport of oranges between different regions largely increase mass loss by up to twofold, FQI by up to ~ 12%, and RSL by up to ~ 15% at retail. Our research also shows that weather temperature is the most important metric during fruit growth affecting various aspects of postharvest orange quality. This study offers valuable insights into the impact of regional weather variations on the quality of oranges available to consumers. These findings could help the citrus industry enhance growing practices, postharvest logistics, retail marketing, and cold chain strategies, thereby improving product quality and consumer satisfaction.

Autumn sunlight promotes aboveground carbon loss in a temperate mixed forest

BackgroundPhotodegradation of plant litter plays a pivotal role in the global carbon (C) cycle. In temperate forest ecosystems, the exposure of plant litter to solar radiation can be significantly altered by changes in autumn phenology and snow cover due to climatic change. How this will affect litter decomposition and nutrient dynamic interacting with forest canopy structure (understorey vs. gaps) is uncertain. In the present study, we conducted a field experiment using leaf litter of early-fall deciduous Betula platyphylla (Asian white birch) and late-fall deciduous Quercus mongolica (Mongolian oak) to explore the effect of change in autumn solar radiation on dynamics of litter decomposition in a gap and understorey of a temperate mixed forest.ResultsExposure to the full-spectrum of not only significantly increased the loss of mass, C, and lignin, but also modified N loss through both immobilization and mineralization during the initial decomposition during autumn canopy opening, irrespective of canopy structure and litter species. These effects were mainly driven by the blue-green spectral region of sunlight. Short-term photodegradation by autumn solar radiation had a positive legacy effect on the later decomposition particularly in the forest gap, increasing mass loss by 16% and 19% for Asian white birch and Mongolia oak, respectively.ConclusionsOur results suggest that earlier autumn leaf-fall phenology and/or later snow cover due to land-use or climate change would increase the exposure of plant organic matter to solar radiation, and accelerate ecosystem processes, C and nutrient cycling in temperate forest ecosystems. The study provides a reference for predictive research on carbon cycling under the background of global climate change.

Transformation of polyester fibre microplastics by sulfate based advanced oxidation processes

Advanced oxidation processes (AOPs) are a potential solution to microplastics (MPs) polluted wastewater but incomplete degradation can result in the formation of smaller fragments with altered surface chemistry. In this work, the impact of sulfate based oxidation on polyester MPs was investigated. Light, heat and ultrasound activation of persulfate resulted in varied degrees of mass loss and surface degradation, as probed by scanning electron microscopy (SEM), atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FTIR). Ultrasonic activation of persulfate resulted in significantly increased fragmentation and formation of smaller microplastic fibrils. Optimised UVC/peroxydisulfate (UVC/PDS) treatment (31.8 mW cm−2, 500 mg L−1) resulted in an 18.5% mass loss over 9 h with clear surface pitting and cracking. Extended treatment under these conditions for 24 h did not result in significantly increased mass loss but did cause an increased degree of surface degradation and increased roughness, indicating that incomplete mineralisation is likely in wastewater systems accompanied by MP transformation. The influence of a real laundry wastewater matrix was also studied and a decreased rate of mass loss was observed due to competing radical reactions with the organic content of the wastewater. Results advance understanding and therefore contribute to mitigating water pollution by MPs, since their physical and chemical transformation in real water treatment systems substantially affects the interaction with organic contaminants and changes the potential environmental risk of MPs.

Comparative study on the thermal runaway characteristics of Li(NixCoyMnz)O2 batteries

Lithium-ion batteries (LIBs) generate substantial gas during the thermal runaway (TR) process, presenting serious risks to electrochemical energy storage systems in case of ignition or explosions. Previous studies were mainly focused on investigating the TR characteristics of Li(NixCoyMnz)O2 batteries with different cathode materials, but they were conducted in isolation. In this study, the thermal runaway characteristics of prismatic cells that use Li(NixCoyMnz)O2 (with x ranging from 0.33 to 0.9) cathode materials in an inert environment, which are commonly used or proposed for energy storage applications, are examined. The findings of this research show that the normalized gas generation rate remains consistent, regardless of the battery capacity or experimental chamber volume, with a value of 0.1 ± 0.03 mol∙Ah⁻1. High-capacity cells have short jetting durations, and a high nickel content leads to increased mass loss rates. The flammability limits of the gases expelled during thermal runaway, represented by the lower flammability limit (LFL), remain stable at 8 ± 1.8 % with minimal variations. However, the upper flammability limit (UFL) varies significantly, ranging from 30 % to 60 %. Increasing the battery capacity or reducing the experimental chamber volume increases the explosion index. The explosive, combustibility, and jetting duration characteristics of the emitted gases from five different battery chemical compositions provide valuable insights for risk assessment in future electrochemical energy storage systems.

Numerical Simulation of the Evaporation Behavior of Fe-Mn Heterogeneous Powder in Selective Laser Melting Process.

Multi-material additive manufacturing using heterogeneous powders as raw materials is one of the important development directions of metal additive manufacturing technology. The evaporation behavior of heterogeneous powders in the selective laser melting (SLM) process has a significant influence on the accuracy of chemical composition control and the quality of the final product. In this paper, the fusion process of Fe20Mn (80 wt.% Fe and 20 wt.% Mn) heterogeneous powder, Fe and Mn elemental powders, and Fe20Mn pre-alloyed powder is numerically simulated using FLOW-3D® software and partially validated through SLM experimental results. The morphology and the characteristics of the flow field and temperature field in the melt pool for four kinds of powder materials are analyzed. The influence of the elemental evaporation behavior of different powders on the mass loss of the Mn element is discussed. The results show that the excessive accumulation of heat increases the maximum temperature of the melt pool, thus increasing mass loss. The Fe20Mn heterogeneous powder has a wider heat-affected zone and a higher peak value of temperature, nearly 400 K higher than that of the Fe20Mn pre-alloyed powders, which exhibits an intensive evaporation behavior. The mass loss of the Mn element obtained from the SLM experiment for Fe20Mn heterogeneous powders forming parts is more than the Fe20Mn pre-alloyed powders' forming parts for different laser powers, up to 17 wt.% at P = 120 W. This tendency is consistent with the numerical analysis of the effect of evaporation behavior of Fe-Mn heterogeneous powder during the SLM process. This study provides the necessary theoretical reference and process guidance for realizing the precise control of the SLM composition of a heterogeneous powder in multi-material additive manufacturing caused by evaporation behavior.

Warm Air Delivery in Adhesive Application: Effect on Bonding Performance and Morphological Outcomes.

Solvent evaporation within an adhesive layer is a crucial step during a bonding process. The aim of this current research was to test whether the use of different air temperatures (20 °C, 40 °C, and 60 °C) for solvent evaporation improves the performance of four adhesive systems to dentin. Sixty non-carious human molar teeth were randomly prepared for micro-tensile bond strength (μTBS) tests. Four different adhesive systems, Prime&Bond Universal (PBU), OptiBond Universal (OBU), OptiBond FL (OBFL), and Clearfil SE (CSE), were applied following the manufacturer's instructions. Three groups based on the air-drying temperature were used: solvent evaporation was performed with either of warm (40 °C), (60 °C), and cold air as control group (20 °C) for 10 s at a distance of 5 cm. In all bonded surfaces, three resin composite (Reflectys, Itena Clinical, Paris, France) layers of 2 mm thickness were built up. The resin-dentin samples were kept in distilled water at 37 °C for 24 h and 6 months, respectively, before μTBS testing. Failure analysis, scanning electron microscopy of resin-dentin bonded interface, and solvent evaporation rate were tested as secondary variables. All analyses were conducted using a significance level of α = 0.05. Bond strength (BS) values were similar among all the adhesive systems used (p > 0.05). Also, the aging factor did not affect the BS (p > 0.05). Only the factor of temperature used for solvent evaporation resulted in a statistically significant effect (p < 0.05), with the temperature of 60 °C being the highest value (p < 0.05). A failure mode evaluation revealed mostly adhesive or mixed modes of failures in all the different temperatures of air used for the solvent evaporation of each adhesive system. The thickness of the adhesive layer and the creation of resin tags varied amongst the temperatures evaluated. For all adhesive systems tested, the use of 40 °C or 60 °C air for solvent evaporation led to an increased mass loss. Warmer temperatures for solvent evaporation contributed positively to bonding performance, enhancing both the quality of the adhesive layer and its interaction with the dentin tissue. Optimizing solvent evaporation with warmer air temperatures (40 °C and 60 °C) significantly improved µTBS, offering a practical means to enhance the quality and longevity of adhesive restorations in esthetic dentistry.

The synergistic effects of a leaf mixture on decomposition change with a period of terrestrial exposure prior to immersion in a stream.

The effect of mixing litter on decomposition has received considerable attention in terrestrial and aquatic (but rarely in both) ecosystems, with a striking lack of consensus in the obtained results. We studied the decomposition of a mixture of poplar and alder in three terrestrial: aquatic exposures to determine (1) if the effect of mixing litter on mass loss, associated decomposers (fungal biomass, sporulation rates, and richness), and detritivores (abundance, biomass, and richness of invertebrate shredders) differs between the stream (fully aquatic exposure) and when litter is exposed to a period of terrestrial exposure prior to immersion and (2) the effect of the mixture across exposure scenarios. The effect of the mixture was additive on mass loss and synergistic on decomposers and detritivores across exposure scenarios. Within scenarios, mass loss and decomposers showed synergistic effects only in the fully aquatic exposure, detritivores showed synergistic effects only when the period of terrestrial was shorter than the period of aquatic exposure, and when the period of terrestrial was equal to the period of aquatic exposure the effect of the mixture was additive on mass loss, decomposers, and detritivores. The species-specific effects also differed among exposure scenarios. Alder affected poplar only when there was a period of terrestrial exposure, with increased sporulation rates and fungal richness in exposure 25:75, and increased mass loss in exposure 50:50. Poplar affected alder only under fully aquatic exposure, with increased mass loss. In conclusion, the synergistic effects of the mixture changed with a period of terrestrial exposure prior to immersion. These results provide a cross-boundary perspective on the effect of mixing litter, showing a legacy effect of exposure to terrestrial decomposition on the fate of plant litter in aquatic ecosystems and highlighting the importance of also assessing the effect of mixing litter on the associated biota and not only on mass loss.

Assessing the impact of despination and wax application on long-term cold stored cactus pears

Glochids and spines on cactus pears represent the main constraint that limit cactus pear consumption, thus their elimination is of pivotal importance for commercialization. Their removal causes abrasions and a reduction of epicuticular wax, which increase mass loss and microbiological spoilage. To mitigate the negative impact of glochids removal, in this study, ‘Gialla’ cactus pears of the second bloom, after despination through rotating brushes, were sprayed with two coating materials: Citrashine or Protégé at 33, 50 or 100%. Fruit were then stored at 20 °C for 1 week or at 6 °C for 4 or 8 weeks followed by 3 or 7 d at 20 °C to simulate marketing conditions. Weight loss, overall appearance and decay incidence were significantly higher in despined fruit compared to control fruit and coated fruit. When applied at 33% Protégé coating showed an overall beneficial effect that contributed to reduce mass loss, decay incidence and to improve fruit appearance without affecting chemical or sensory quality. Protégé at 50% and 100% reduced weight loss but resulted phytotoxic and worsened fruit appearance and had a negative impact on the percentage of marketable fruit, besides increasing the degradation of juice chemical compounds and altering sensory attributes. Citrashine had a good impact on preventing decay slowing down mass loss and overall appearance but altered the chemical and the eating quality as Protégé coating when applied at 50% or 100%.However, in fruit directly placed in simulated marketing conditions at 20 °C, despination neither altered fruit quality nor reduced fruit marketability. Thus, replacement of epicuticular waxes lost by despination with coatings can be beneficial for long term storage of cactus pear, provided that the applied material is not phytotoxic and does not impair the fruit gas exchange.

TRIBOLOGICAL PROPERTIES OF A SILICONE-BASED COMPOSITEWITH INORGANIC ADDITIVES

The paper presents the results of experimental studies, including tribological tests of silicone-based compositeswith additions of hexagonal boron nitride (hBN) and titanium (Ti). The tests were conducted on a BrukerUMT2 tribotester and using a pin-on-disk setup developed by the authors, without a lubricating medium,and they employed a steel ball made of 100Cr6 steel and a sample made of the composite. During the tests,the products were not removed from the contact area. The paper analyzes the influence of additives on thetribological properties of the composite, i.e., the coefficient of friction (COF) as a function of distance and thewear of the tested samples. In the case of samples containing hBN, the COF decreases with an increase in itscontent. After reaching a volumetric percentage concentration of 20%, it begins to stabilize with the increasein mass loss. The profiles of COF changes as a function of distance for samples with different additivecontents are comparable. The self-lubricating properties of hBN have been confirmed. The addition of Tireduces the COF value, which decreases with the increase in the Ti content. Samples with a mass percentageconcentration exceeding 100% of the Ti content have a COF value equal to the initial value for silicone. Thecomposite containing hBN has a lower COF value than samples with the Ti addition, and the wear tracks ontheir surface are narrower and shallower.

(Invited) Thermal Stability and Thermal Energy Measurements for a Lithium-Ion Pouch Cell with Different State of Health

Lithium-ion batteries have developed into one of the most popular secondary batteries on the market today due to high voltage, long lifetime and high energy density. However, lithium-ion cells have issues related to safety. Since the development of an internal short in a lithium-ion battery at present cannot be detected [1, 2], the physical reactions of a lithium-ion battery must be managed by a robust battery design. Lithium-ion batteries used in the Norwegian maritime sector need to be approved by thermal propagation tests as verification of design [3]. During a propagation test, one or several lithium-ion cells are forced into thermal runaway either by heating, overcharge or nail penetration. The acceptance criterion is either; no spread of thermal runaway between cells in a module, or between modules. Despite these rules, several fires have been reported. Of the more well-known are the fire/gas explosion onboard the electric car ferry ‘MF Ytterøyningen’ [4] and the fire on board ‘MS Brim’ [5].A commercial 64 Ah lithium-ion pouch cell was studied by forcing thermal runaway with nail penetration, heating and overcharge to evaluate the energy release based on the abuse method. Two cells aged to 80% state of health (SoH) were also studied with accelerating rate calorimetry and nail penetration to see the effect of cell ageing on thermal stability, critical temperature, energy release and jet flame severity. These methods were combined with diagnostics and cell disassembly to relate the differences found in degradation and safety to the diagnostic data. The safety results will be highlighted in this presentation.The uncycled cells safety properties were rated by fire and mass losses. All cells caught fire, and the mass loss ranged from 38.8% for nail penetration, 55.4% for heat ramp and 72.3% for overcharge. Based on mass loss only, overcharge is the most severe abuse method. Contrary to this, energy released to the solid surroundings during thermal runaway (internal thermal energy) decreased with increasing mass loss. Mass loss could be a key feature in explaining energy release and abuse method severity, see Figure 1. As a result, an uncycled cell in a battery module may withstand the heat from a neighboring thermal runaway during overcharge but may be driven into thermal runaway by a nail penetration test.Cyclic ageing at 25 °C to 80% SoH had a minor impact on abuse severity and mass loss. However, cycled cells are found to lose more electrical energy than internal thermalenergy. Cell electrical energy loss is not directly related to a change in the cell's internal thermal energy. Thermal runaway temperature was found to decrease for a cycled cell, from 204°C to 182°C.Dependent on abuse method, a false sense of security may result from the propagation test. Possibly, a module could show no cell-to-cell propagation with the overcharge method but be driven into thermal runaway propagation by a nail penetration. A decrease in thermal stability combined with a change in internal thermal energy could be hazardous and might be an end-of-life criteria. It is of vital importance to develop diagnostic tools capable of detecting a potentially hazardous drop in thermal stability for aged lithium-ion cells.Acknowledgements: This work was part of the BattMarine project (281005), funded by the Research Council of Norway and Norwegian industry.

Annual to seasonal glacier mass balance in High Mountain Asia derived from Pléiades stereo images: examples from the Pamir and the Tibetan Plateau

Abstract. Glaciers are crucial sources of freshwater in particular for the arid lowlands surrounding High Mountain Asia. To better constrain glacio-hydrological models, annual, or even better, seasonal information about glacier mass changes is highly beneficial. In this study, we evaluate the suitability of very-high-resolution Pléiades digital elevation models (DEMs) to measure glacier mass balance at annual and seasonal scales in two regions of High Mountain Asia (Muztagh Ata in Eastern Pamirs and parts of western Nyainqêntanglha, south-central Tibetan Plateau), where recent estimates have shown contrasting glacier behaviour. The average annual mass balance in Muztagh Ata between 2019 and 2022 was −0.07 ± 0.20 m w.e. a−1, suggesting the continuation of a recent phase of slight mass loss following a prolonged period of balanced mass budgets previously observed. The mean annual mass balance in western Nyainqêntanglha was highly negative for the same period (−0.60 ± 0.15 m w.e. a−1), suggesting increased mass loss rates compared to the approximately previous 5 decades. The 2022 winter (+0.13 ± 0.24 m w.e.) and summer (−0.35 ± 0.15 m w.e.) mass budgets in Muztagh Ata and western Nyainqêntanglha (−0.03 ± 0.27 m w.e. in winter; −0.63 ± 0.07 m w.e. in summer) suggest winter- and summer-accumulation-type regimes, respectively. We support our findings by implementing the Sentinel-1-based Glacier Index to identify the firn and wet-snow areas on glaciers and characterize the accumulation type. The good match between the geodetic and Glacier Index results supports the potential of very-high-resolution Pléiades data to monitor mass balance at short timescales and improves our understanding of glacier accumulation regimes across High Mountain Asia.

Valorization of organic municipal solid waste to enhanced solid biofuel: torrefaction kinetics, torrefied solid fuel performance, and fuel properties

ABSTRACT The kinetics of the torrefaction process have been studied in various reactors. However, no study reported the torrefaction kinetics of organic municipal solid waste (OMSW) in a helical screw rotation-induced (HSRI) fluidized bed reactor. This study produced torrefied solid fuel, and the kinetic parameters of the OMSW torrefaction process were determined. The results showed that increasing temperature and residence time from 200 to 300°C and 0 to 40 minutes increased mass loss, calorific value, ash content, fixed carbon, energy density, and carbon content. Conversely, mass yield, volatile matter, energy yields, oxygen-to-carbon, and hydrogen-to-carbon ratios decreased. The calorific value experienced notable growth, varying from 17.80 to 26.18 MJ/kg, with increased residence time and temperature. The one-step kinetic model using a first-order reaction accurately predicts reaction data for long residence times with a maximum error of 2.42% at 300°C and 10 minutes and is useful for designing and scaling up the HSRI fluidized bed reactor within the temperature and mass loss ranges of 220–300°C and 2.61–47.38%. The OMSW torrefaction frequency factor and activation energy were 0.2036 s−1 and 24.46 kJ/mol, respectively. The findings of this study showed that residence time has less effect on the torrefaction process than temperature.

Photocatalytic degradation of polyethylene and polystyrene microplastics by α-Fe2O3/g-C3N4.

This study investigated the photodegradation of microplastics (MPs) by α-Fe2O3/g-C3N4. The effects of α-Fe2O3/g-C3N4 on MPs' surface were investigated through various techniques. With the addition of α-Fe2O3/g-C3N4 and under visible light irradiation, cracks and folds were observed on the MP films and particles. Compared to the treatment without photocatalyst addition, the mass loss of MPs increased with irradiation time when α-Fe2O3/g-C3N4 was added. Specifically, polystyrene films and particles in water showed 9.94% and 7.81% increased mass loss, respectively. The degradation of MPs using α-Fe2O3/g-C3N4 demonstrated the behavior consistent with the pseudo-first-order kinetic model. The presence of α-Fe2O3/g-C3N4 led to an increase in surface oxygen-containing functional groups and crystallinity while decreasing the average molecular weight of MPs. After 30days of irradiation, the characteristic tensile bands of MPs with α-Fe2O3/g-C3N4 significantly increased, and the detection of carboxyl bands indicated the formation of carboxylic acid, ketones, and lactones as degradation products.

Experimental and numerical investigation of corroded cold-formed steel channel section columns subjected to in-plane compression and bending

This paper investigates the effect of corrosion on bearing capacity of corroded cold-formed steel (CFS) channel section columns subjected to in-plane compression and bending. Herein, 14 CFS columns with different column lengths and corrosion degrees were investigated. The mass loss rate, surface morphology, and initial geometric imperfections of corroded CFS columns were measured. The eccentric compression test of corroded CFS columns that were accelerated corrosion by the outdoor periodic spray test were carried out. The relationships among the failure mode, load–strain curves and load–axial displacement curves, and mass loss rate were analyzed, and then the deterioration laws of bearing performance of corroded CFS channel section columns were discussed. The non-linear finite element model for corroded CFS columns considering surface morphology was then developed by using Geomagic Studio and ABAQUS. The results indicated that the local and overall initial geometric imperfections of corroded specimens were greater than those of non-corroded specimens. With increasing mass loss rate, the distortional buckling deformation of corroded CFS columns occurred in advance and the failure locations were diversified. Corrosion exhibited a greater impact on the buckling critical load than on the ultimate load and post-buckling strength. The failure positions of corroded CFS channel section columns subjected to in-plane compression and bending were found to be mainly related to the areas with severe corrosion of the flange.