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Magnetocaloric materials, which exploit reversible temperature changes induced by magnetic field variations, are promising for advancing energy-efficient cooling technologies. The potential integration of two-dimensional materials into magnetocaloric systems represents an emerging opportunity to enhance the magnetocaloric cooling efficiency. In this study, we use atomistic spin dynamics simulations based on first-principles parameters to systematically evaluate how magnetocaloric properties transition from three-dimensional (3D) to two-dimensional (2D) ferromagnetic materials. We find that 2D features such as reduced Curie temperature, sharper magnetic transition, and higher magnetic susceptibility are beneficial for magnetocaloric applications, while the relatively higher lattice heat capacity in 2D can compromise achievable adiabatic temperature changes. We further propose GdSi 2 as a promising 2D magnetocaloric material. Our calculation predicts that GdSi 2 exhibits an isothermal entropy change Δ S M of 22.5 J kg − 1 K − 1 and an adiabatic temperature change Δ T a d of 6.2 K, near the hydrogen liquefaction temperature (T C ≈ 25 K). Our analysis offers valuable theoretical insights into the magnetocaloric effect in 2D ferromagnets and demonstrates that 2D ferromagnets hold promise for cooling and thermal management applications in compact and miniaturized nanodevices. [ABSTRACT FROM AUTHOR]

Interest has emerged recently in addressing the long‐standing issue of waste plastic disposal and environmental challenges through the co‐liquefaction of waste plastics with eco‐friendly renewable biomass resources, including microalgae biomass and lignocellulosic biomass, to produce biofuels. Co‐liquefaction provides a viable alternative for managing plastic waste while contributing to biofuel production. The purpose of this article is to provide a comprehensive review of the advances in the co‐liquefaction of various mixtures of plastic waste and different types of biomass feedstocks (lignocellulosic and algal) for the production of biofuels. The influence of various reaction parameters, such as feedstock composition (blending ratio), temperature, catalyst type and loading, solvents, and reaction time on the product yield are explored. The synergistic interaction during the co‐liquefaction of biomass and plastic and the distribution and properties of biofuel products are also discussed. The findings demonstrate that maximum product yields vary depending on the final temperature, and the blending ratio plays a crucial role in determining the distribution of liquefaction products. Of particular interest is biocrude oil, the components of which are influenced by the composition of the feedstock material. The distribution of organic elements in the biochar is contingent upon the type of plastic used. Although the analysis of gas‐phase components is often overlooked, the reaction medium's composition is shown to impact the resulting gas composition. Finally, based on the insights gleaned from the literature, this review presents future perspectives on the subject matter. In general, the co‐liquefaction process offers a viable option for sustainable biofuel production and is a promising approach to address the waste plastics disposal challenges effectively, contributing to the valorization of plastic waste to achieve a circular bioeconomy in the future. [ABSTRACT FROM AUTHOR]

Hydrothermal liquefaction is a new, sustainable pathway to generate biogenic liquids from organic resources. The technology is compatible with a wide variety of resources such as lignocellulosic resources, organic waste, algae, and sewage sludge. The chemistry is complex and predictions of yields are notoriously difficult. Understanding and modeling of hydrothermal liquefaction is currently mostly based on a simplified biochemical analysis and product yield data. This paper presents a large dataset of 2439 experiments in batch reactors that were extracted from 171 publications in the scientific literature. The data include biochemical composition data such as fiber content and composition, proteins, lipids, carbohydrates, and ash. The experimental conditions are recorded for each experiment as well as the reported yields. The objective of this paper is to make a large database available to the scientific community. This database is analyzed with machine‐learning tools. The results show that there is no consensus on the analysis techniques, experimental procedures, and reported data. There are many inconsistencies across the literature that should be improved by the scientific community. Machine‐learning tools with a large dataset allow the generation of reliable yield production tools with a large application field. Given the accuracy of the data, the overall precision of prediction in an extrapolation to new results can be expected to be around 10%. [ABSTRACT FROM AUTHOR]

Camelina sativa plant residue was used as feedstock for the production of biogasoline (a mixture of paraffinic and olefinic hydrocarbons) by catalytic hydrothermal liquefaction (cHTL) process. The experiments were conducted at temperature range 200–375°C and pressure range 10–19 MPa. Molecular hydrogen was added for the hydro-deoxygenation processes. Various experiments were performed to understand the contributions of process parameters such as temperature, pressure, hydrogen, and retention time on reaction conversion and products distribution. This was followed by screening of different catalyst supports – γ-Al2O3, HZSM-5, SiO2-Al2O3, SBA-15, and Al2O3-HZSM-5 to understand their impacts as well as catalytic activities. The Al2O3/HZSM-5 exhibited the best properties and was impregnated with a varying range of cobalt metal for the HTL of Camelina sativa. The 5%Co/γ-Al2O3-HZSM-5 catalyst exhibited highest liquefaction conversion (79%) and biogasoline yield (43%) at optimized reaction conditions due to the presence of strong brønsted acidity on the catalyst were that enhanced both the hydrocarbon cracking and hydrogenation leading to the production of low boiling point and low molecular weight hydrocarbon within the boiling point range of fossil gasoline. Across all the data point used in the work, the average deviation was within ± 3%, these are mostly indicated by the error bars. [ABSTRACT FROM AUTHOR]

Hydrogen liquefaction is essential for the efficient storage and transportation of hydrogen. In the liquefaction process, catalytic ortho‐para conversion is crucial to achieve a product with at least 95 % para‐hydrogen to reduce boil‐off losses. The proposed hydrogen liquefaction process using a catalyst‐filled heat exchanger for continuous ortho‐para conversion is modeled through steady‐state thermal simulations in Aspen HYSYS. Additionally, an ejector is integrated to reliquefy boil‐off gas. The proposed design achieves a specific energy consumption (SEC) of 10.50 kWh (kgLH2${\mathrm{kg}}_{{\mathrm{LH}}_2}$)−1 and an exergy efficiency (EXE) of 30.1 %, which is 18 % lower in SEC compared to processes with separate converters. The integrated approach enhances energy utilization and offers references for future hydrogen liquefiers. [ABSTRACT FROM AUTHOR]

To clarify the influence range and saturation distribution after the biogas desaturation method is applied, a three-dimensional model is established with TOUGH2 software to analyze the effect of construction parameters such as grouting volume, grouting rate, grouting depth, nitrogen source concentration, and soil porosity. After that, the sensitivity of the parameters on the influence range is determined. The grouting volume and soil porosity are the most sensitive to the lateral and vertical influence range, respectively. This study provides a basis for the engineering practice of treating liquefiable subgrade by the biogas desaturation method. [ABSTRACT FROM AUTHOR]

In recent years, algae have emerged as a promising feedstock for biofuel production, due to their eco-friendly, sustainable, and renewable nature. Various methods, including chemical, biochemical, and thermochemical processes, are used to convert algal biomass into biofuels. Pyrolysis, a widely recognized thermochemical technique, involves high temperature and pressure to generate biochar and bio-oil from diverse algal sources. Various pyrolytic processes transform algal biomass into biochar and bio-oil, including low pyrolysis, fast pyrolysis, catalytic pyrolysis, microwave-assisted pyrolysis, and hydropyrolysis. These methods are utilized to convert a range of microalgae and cyanobacteria into biochar and bio-oil. In this publication, we will discuss catalytic pyrolysis using mesoporous materials, such as SBA-15. Mesoporous catalysts have earned significant attention for catalytic reactions, due to their high surface area, facilitating the better distribution of impregnated metal. Pyrolysis conducted in the presence of a mesoporous catalyst is viewed more as efficient, compared to reactions occurring within the smaller microporous cavities of traditional zeolites. SBA-15 supports with incorporated Zr and/or Ce were synthesized using the direct hydrothermal synthesis method. The catalyst was characterized using structural and morphological technical analysis and utilized for the pyrolysis reaction of the algal biomass. [ABSTRACT FROM AUTHOR]

We report a transformative epoxy system with a microalgae-derived bio-binder from hydrothermal liquefaction processing (HTL). The obtained bio-binder not only served as a curing agent for conventional epoxy resin (e.g., EPON 862), but also acted as a modifying agent to enhance the thermal and mechanical properties of the conventional epoxy resin. This game-changing epoxy/bio-binder system outperformed the conventional epoxy/hardener system in thermal stability and mechanical properties. Compared to the commercial EPON 862/EPIKURE W epoxy product, our epoxy/bio-binder system (35 wt.% bio-binder addition with respect to the epoxy) increased the temperature of 60% weight loss from 394 °C to 428 °C and the temperature of maximum decomposition rate from 382 °C to 413 °C, while the tensile, flexural, and impact performance of the cured epoxy improved in all cases by up to 64%. Our research could significantly impact the USD 38.2 billion global market of the epoxy-related industry by not only providing better thermal and mechanical performance of epoxy-based composite materials, but also simultaneously reducing the carbon footprint from the epoxy industry and relieving waste epoxy pollution. [ABSTRACT FROM AUTHOR]

Microbial-induced calcium carbonate precipitation (MICP) is an emerging in situ grouting technology for sand ground improvement, slope stability, and subgrade reinforcement, featuring rapid implementation and low energy consumption. The precipitated calcium carbonate crystals can rapidly fill and cement sand particles so as to form a new soil structure that effectively reduces liquefaction sensitivity and dynamic damage. The centrifuge shake table test is an effective method for simulating liquefaction of sandy soil layers under shear wave excitation. Many studies have been conducted on this topic in recent years. However, the study on dynamic response, especially the liquefaction resistance of MICP-cemented sands by centrifuge shake table tests, is rare. In order to investigate the cementation effect of microbial treatment, centrifuge shake table tests were performed on two models, i.e., untreated and MICP cemented sand model. The test results indicated that, compared with untreated sand model, the liquefaction resistance of the MICP model was significantly improved in terms of acceleration response, shear stiffness, stress–strain relationship, and ground surface settlement. This study contributes to a better understanding of the mechanical law in the liquefaction process and enriches the engineering application of microbial grouting treatment of sand foundation prone to liquefaction. [ABSTRACT FROM AUTHOR]

The technical note presents findings of an experimental study on the applicability of equivalent intergranular void ratio e*eq concept in sand-plastic fines mixtures under monotonic and cyclic loading. The results of undrained triaxial tests conducted on mixtures of Hostun sand with varying amounts (0% to 20%) and types of plastic fines (kaolin and calcigel bentonite) were already presented in two previous studies. The e*eq for the mixtures under various initial densities was calculated using the parameter b. Preliminary results show that the concept of e*eq seems to hold valid in the e-p space considering monotonic tests as well as being able to capture the variation of the cyclic resistance ratio for a predefined number of cycles to initial liquefaction from cyclic undrained tests even in mixtures with plastic fines below threshold fines content. However, the need for further studies is duly acknowledged. [ABSTRACT FROM AUTHOR]

The utilization of microalgae to treat carbon dioxide (CO2)-rich industrial off-gas has been suggested as both beneficial for emissions reduction and economically favorable for the production of microalgal products. Common sources of off-gases include coal combustion (2–15% CO2), cement production (8–15% CO2), coke production (18–23% CO2), and ore smelting (6–7% CO2). However, industrial off-gas also commonly contains other acid gas components [typically nitrogen oxides (NOX) and sulfur dioxide (SO2)] and metals that could inhibit microalgae growth and productivity. To utilize industrial off-gas effectively in microalgae cultivation systems, a number of solutions have been proposed to overcome potential inhibitions. These include bioprospecting to identify suitable strains, genetic modification to improve specific cellular characteristics, chemical additions, and bioreactor designs and operating procedures. In this review, results from microalgae experiments related to utilizing off-gas are presented, and the outcomes of different conditions discussed along with potential solutions to resolve limitations associated with the application of off-gas. [ABSTRACT FROM AUTHOR]

This study investigates the effect of non-plastic fines content of sand–silt mixtures on excess pore water pressure generation using an energy-based approach. For this purpose, an experimental program was designed and conducted on mixtures of Firoozkuh sand No. 161 and Firoozkuh silt. A total of 35 undrained strain-controlled cyclic triaxial tests were performed on the reconstituted specimens of sand–silt mixtures, with a wide range of effective parameters such as relative density, effective confining stress, and fines content. Also, to present a more generalized and precise model, 37 undrained cyclic tests were collected from previous studies. Then, using nonlinear regression analysis and the results of these 72 tests, a model, relating residual excess pore water pressure ratio ( r u ) to the ratio of dissipated energy to capacity energy ( W / W liq ), is proposed. The results indicated that initial effective confining stress has a negligible effect on the r u - W / W liq trend and so, the calibration parameter of the model only depends on the relative density and fines content. Convincingly, the accuracy of the proposed model was verified using the results of a series of centrifuge tests, reported by others, and the recorded data of wildlife downhole array site during the Superstition Hills 1987 earthquake. The proposed model is practical, applicable to various sands and sand–silt mixtures with nonplastic fines contents, and able to be calibrated using convenient parameters (i.e., relative density and fines content). Finally, the model can be easily implemented in site response analysis for energy-based liquefaction potential evaluation. [ABSTRACT FROM AUTHOR]

The microbial induced partial saturation (MIPS) technique is the new environmentally friendly, cost-effective technique applicable under existing structures for mitigating sand liquefaction. The current study investigated the effectiveness of MIPS for mitigating sand liquefaction under undrained static loading. A series of undrained static triaxial tests were conducted to examine the influence of biogenic gas production through microbial denitrification on poorly graded sand at various relative densities. Initial batch experiments revealed that increased nitrate concentrations resulted in a decreased degree of saturation. Loosely and medium-dense saturated samples exhibited positive pore pressure during loading, which was reduced through biological desaturation, resulting in increased undrained shear strength ratios. Dense saturated and desaturated samples produced negative excess pore pressure, decreasing the undrained strength of treated samples due to dilative behavior. The undrained stress–strain behavior of loose and medium-dense sand transitioned from strain softening to strain hardening as the degree of saturation decreased from 100 to 90%. However, dense sand exhibited strain-hardening behavior with decreased saturation from 100 to 95%. Decreasing saturation levels reduced instability susceptibility, resulting in more stable soil behavior and decreasing the potential for large strains and instability. The study demonstrated a reduction in the Liquefaction Potential Index (LPI) for both loose and medium-dense sand as the degree of saturation decreased from 100 to 90%. These findings highlight the potential of MIPS as an effective technique for mitigating sand liquefaction and offer insights into its underlying mechanisms. [ABSTRACT FROM AUTHOR]

Crystallization of alloys from a molten state is a fundamental process underpinning metallurgy. Here the direct imaging of an intermetallic precipitation reaction at equilibrium in a liquid‐metal environment is demonstrated. It is shown that the outer layers of a solidified intermetallic are surprisingly unstable to the depths of several nanometers, fluctuating between a crystalline and a liquid state. This effect, referred to herein as crystal interface liquefaction, is observed at remarkably low temperatures and results in highly unstable crystal interfaces at temperatures exceeding 200 K below the bulk melting point of the solid. In general, any liquefaction process would occur at or close to the formal melting point of a solid, thus differentiating the observed liquefaction phenomenon from other processes such as surface pre‐melting or conventional bulk melting. Crystal interface liquefaction is observed in a variety of binary alloy systems and as such, the findings may impact the understanding of crystallization and solidification processes in metallic systems and alloys more generally. [ABSTRACT FROM AUTHOR]

Hydrothermal liquefaction (HTL) is an efficient technology for converting biomass to platform compounds. It has great potential for reducing the dependence on fossil fuels. The HTL of waste biomass has been extensively studied in recent years due to both its environmental and economic benefits. However, most woody waste contains a large amount of cellulose, and it is difficult to be sufficiently decomposed to valuable chemicals. Phycocyanin, a key component of algae, is easily degraded under high-temperature liquefaction conditions. In this work, focusing on bio-oil generation properties, the co-liquefaction characteristics and synergistic mechanisms of a-cellulose and phycocyanin were explored. The findings revealed a maximum bio-oil yield of 33.1 wt% under the optimal conditions (300 °C for 40 min), with a notable positive synergistic effect of 13.5 wt%. Chemical composition analysis indicated distinct compositional differences between the bio-oils derived from individual and dual feedstock. The amounts of pyridine and pyrimidine compounds increased due to the enhanced co-liquefaction. The results also highlighted the influence of temperature on the degree of conversion and product distribution. Finally, preliminary chemical reaction pathway was elucidated, underscoring the potential of integrating microalgae and woody biomass for enhanced bio-oil production. [ABSTRACT FROM AUTHOR]

Granular materials may undergo static liquefaction under undrained shearing, which is related to many natural hazards, such as landslides. Despite great efforts, the overall process of static liquefaction remains largely unclear. Numerical undrained shear tests on granular assemblies are performed using the discrete element method, and network-based methods are introduced to investigate the evolution of the contact network. The occurrence of static liquefaction is attributed to the collapse of the contact network induced by contact loss. The weak subnetwork is broken before reaching the liquefaction point, while the strong contact subnetwork remains relatively unchanged. The failure of the strong subnetwork is further investigated by the mechanical features of two important mesoscopic structures, namely force chains and contact loops. The buckling events with buckling ratio exceeding the envelope line and the transition from small loops to large loops significantly destroy the stability of force chains, which causes the failure of force chains and eventually the occurrence of static liquefaction. The relationship of macroscopic stress with microscopic and mesoscopic structures is also identified. The evolution of node degree and global efficiency versus macroscopic stress presents a two-stage development mode, and the buckling events accelerates the transition of the development mode. Our analysis elucidates the occurrence of static liquefaction from microscopic and macroscopic perspectives, which are essential for better prediction and modeling of the catastrophic failures under undrained loading path of granular materials. [ABSTRACT FROM AUTHOR]

This work studies red mud, a residue from the processing of bauxite, as a support catalyst in the thermocatalytic reforming (TCR) process, using wood, digestate, and straw as case studies. Thermocatalytic reforming is a thermochemical process for the conversion of biomass into biofuels, combining intermediate pyrolysis and catalytic reforming and resulting in high‐quality biofuels. The quantity and quality of the catalyst in the postreformer is vital as it influences the reactions taking place in it. Normally, nonreactive components of the char produced in the process act as the catalyst in the postreformer but adding a support catalyst may improve the products. In this work, red mud is introduced in the process by mixing it with the feedstock in a ratio of 1:3. The results, in comparison with normal TCR experiments on the same feedstock materials, show that the introduction of red mud into the process generally reduces the biochar yield and generally increases the biogas and product water yields, and the bio‐oil yield remains constant. Its introduction also increases the hydrogen fraction of the gas and tends to reduce the nitrogen and sulfur content of the products, thus improving their quality. These observations are consistent across feedstock materials and postreformer temperatures. The results therefore suggest that red mud is a good support catalyst for increasing the gas yield, increasing the hydrogen fraction of the gas, and improving the quality of the products from the TCR process. [ABSTRACT FROM AUTHOR]

The undrained shearing behavior of the Jhelum Riverbed sands and the effect of fines content on their overall response and their static liquefaction potential are still elusive. In this context, the present study aims to understand the undrained shearing response and static liquefaction potential of Jhelum riverbed sands through a series of isotropically consolidated undrained compression (CIUC) triaxial tests. The effect of sand type and fines content were established through CIUC triaxial tests conducted on clean sands obtained from three different locations (Khanabal, Rajbagh, and Sopore) along the Jhelum River and sand-silt mixtures. Results showed that volumetric compressibility (mv) decreased by 67, 65, and 46% as the relative density increased from 15 to 50% for KS, RS, and SS sands, respectively. Compared to clean sands, an increase of 23 and 15% in mv was observed with the addition of 7 and 14% non-plastic fines, respectively. An increase in the undrained shearing resistance by factors of 2.12, 3.08, and 1.98 for KS, RS, and SS, respectively, is observed as the relative density increases from 15 to 50%. An increase in undrained strength by 79.2% is observed when the initial effective confining pressure ( p i ′ ) is increased from 50 to 150 kPa. It was also observed that Jhelum sands follow normal behavior of increasing contractile tendency as p i ′ increased from 50 to 150 kPa. Specimens with larger mean grain diameter (D50) and lower coefficient of uniformity (CU) values exhibited higher undrained strength as well as higher liquefaction resistance. Higher roundness and sphericity values facilitate a higher generation of excess pore water pressure, resulting in higher liquefaction potential. With the addition of non-plastic fines, the Sopore Sand-silt mixture exhibited higher liquefaction potential, more strain-softening behavior, and higher excess pore pressure, resulting in 83 and 51% reduction in p i ′ at 7 and 14% fines content, respectively. A unique critical state line in q - p ′ space is observed for sand silt mixtures. [ABSTRACT FROM AUTHOR]

The solubility of impurities in hydrogen at cryogenic temperatures is essential information for the design of liquid hydrogen plants. However, large data scatter and inconsistent predictions of impurity solubility by thermodynamic models mean that expensive engineering design margins are required to avoid blockages in cryogenic equipment. Here we report the combination of a stereomicroscope, commercial cryocooler and pressure cell to directly visualise solid impurity freeze-out and melting in stirred hydrogen at low temperatures and elevated pressures. Scattered literature data for nitrogen's solubility in hydrogen are compared to new solid-fluid equilibrium (SFE) measurements for a 1000 ppm N 2 in H 2 mixture at (1.8–5) MPa, and (42–52) K. These results were used to improve solubility models implemented in the ThermoFAST software package, achieving a three-fold decrease in the root-mean-square deviations between the SFE predictions and the data, helping lower the risk of impurity freeze-out in hydrogen liquefaction. [Display omitted] • High pressure optical apparatus for impurity freeze-out in hydrogen demonstrated. • Apparatus used to directly image nitrogen solids freezing out of fluid hydrogen. • Model for solubility of N2 in H2 tuned to new measurements and literature data. • Tuned model significantly improves predictions of nitrogen solubility in hydrogen. • Outcomes from this work are relevant to the design of liquid hydrogen plants. [ABSTRACT FROM AUTHOR]

The raw materials of Poly(ethylene terephthalate) (PET) are derived from petroleum‐based resources, which are no sustainable. Therefore, previous researchers introduced biomass‐derived 2,5‐tetrahydrofurfuryl dimethanol (THFDM) into PET. However, its heat resistance has decreased compared to PET. In this paper, a novel bio‐based copolyester, poly(ethylene glycol‐co‐2,5‐tetrahydrofuran dimethanol‐co‐isosorbide terephthalate) (PEIFT), is prepared by introducing biomass‐derived isosorbide (ISB) and THFDM into the PET chains through melting copolymerization process. With the introduction of ISB content, copolyesters' hydrophilicity and rigidity improve. Compared to PET, glass transition temperature (Tg) increases by over 5 °C. In addition, the toughness and spinning performance of PEIFT have also been improved as a result of the addition of THFDM components. The hydrophobicity of PEIFTs electrospinning is greatly improved, with a contact angle exceeding 135°. Finally, due to the good hydrophobicity of PEIFTs nanofibers, they have potential application value in the manufacture of hydrophobic nanofiber and filter films. Given its biomass source and excellent performance, they make it easier to replace materials derived from petroleum. [ABSTRACT FROM AUTHOR]

In a world facing the challenges of climate change, it is imperative to prioritize the search for sustainable technical solutions. This study focuses on evaluating the environmental impact of using bio-coke compared to traditional metallurgical coke, employing Life Cycle Assessment (LCA) as the evaluation tool. Bio-coke, produced from a blend of coking coals enriched with biomass, offers greater environmental potential than traditional coke due to a reduced share of non-renewable raw materials. The steel and coking industries are significant contributors to carbon dioxide emissions. LCA provides a comprehensive assessment of the environmental impact of bio-based additives, considering raw material deliveries, the coking process, application in metallurgy, and product end-of-life disposal. The analysis results indicate that the use of biomass additives leads to lower greenhouse gas emissions compared to coke production without bio-additives. Given the urgency of addressing global warming and the increasing demand for sustainable energy sources, this study's findings can advocate for bio-coke as a more environmentally friendly alternative to traditional coke in the steel industry. [ABSTRACT FROM AUTHOR]

Liquefaction conversion technology has become one of the hottest biomass conversion methods due to its flexible material selection and extensive product applications. Exploring biomass liquefaction conversion focuses on catalysts, biomass/water ratio, and reaction temperature. However, it is found that solvents are crucial in the biomass liquefaction process and significantly impact the type of liquefied products and bio-oil yield. Given the current rapid development trend, timely sorting and summary of the solvent effect in the biomass liquefaction process can promote the subsequent development and industrialization of more efficient and cleaner biomass liquefaction technology. Therefore, this review first introduces the characteristics of water as the liquefaction solvent, then summarizes the effects of organic solvents on liquefaction, and finally elaborates on the synergistic effect of co-solvents, which provides a more systematic overview of solvent effects in the liquefaction process. Meanwhile, prospects are put forward for the future development of biomass liquefaction conversion. [ABSTRACT FROM AUTHOR]

Gas flaring has been identified as a major contributor to global warming and climate change. It is used either as a safety measure or as a means of disposal for technical or economic reasons. Over 250 toxins have been directly/indirectly associated with gas flaring and its associated emissions. Most of these toxins have been known to have significant inimical impacts on humans' health, plant biodiversity, and the environment. With the recent rise in global energy insecurity, several EU countries have either returned to coal power generation or extended the lifetime of their coal-fired plants thereby increasing anthropogenic carbon emissions. This increase in carbon emission has necessitated the re-evaluate of gas flare practices vis-à-vis the environmental challenges and the financial potentials. This paper presents a holistic review of gas flaring, its types, composition, systems design, estimation methods, social and environmental challenges, the abatement measures, and the re-utilization strategies. It identified the potential to save a minimum of US$10.4 billion globally if more stringent gas flare abatement measures were pursued. Furthermore, the paper highlights the recent trends in flare gas re-utilization technologies such as the production of bioproducts which has been reported to hold a potential for an annual production of about 148 million bbl of biocrude and 67 million metrics of algae protein from 140 bcm of globally flared gas. Finally, it explored the possible way forward and stringent measures that can be pursued to disincentivize gas flare and also increase investments in gas processing technologies. [ABSTRACT FROM AUTHOR]

The hydrothermal liquefaction (HTL) of composite household waste (CHW) was investigated at different temperatures in the range of 240–360 °C, residence times in the range of 30–90 min, and co-solvent ratios of 2–8 ml/g, by utilising ethanol, glycerol, and produced aqueous phase as liquefaction solvents. Maximum biocrude yield of 46.19% was obtained at 340 °C and 75 min, with aqueous phase recirculation ratio (RR) of 5 ml/g. The chemical solvents such as glycerol and ethanol yielded a biocrude percentage of 45.18% and 42.16% at a ratio of 6 ml/g and 8 ml/g, respectively, for 340 °C and 75 min. The usage of co-solvents as hydrothermal medium increased the biocrude yield by 35.30% and decreased the formation of solid residue and gaseous products by 19.82% and 18.74% respectively. Also, the solid residue and biocrude obtained from co-solvent HTL possessed higher carbon and hydrogen content, thus having a H/C ratio and HHV that is 1.01 and 1.23 times higher than that of water as hydrothermal medium. Among the co-solvents, HTL with aqueous phase recirculation resulted in higher carbon and energy recovery percentages of 9.36% and 9.78% for solid residue and 52.09% and 56.75% for biocrude respectively. Further qualitatively, co-solvent HTL in the presence of obtained aqueous phase yielded 33.43% higher fraction of hydrocarbons than the pure water HTL and 7.70–17.01% higher hydrocarbons when compared with ethanol and glycerol HTL respectively. Nitrogen containing compounds, such as phenols and furfurals, for biocrudes obtained from all HTL processes, were found to be present in the range of 8.30–14.40%. [ABSTRACT FROM AUTHOR]

To explore the feasibility of geogrid reinforcement as a promising countermeasure to improve the liquefaction and post-liquefaction resistance of calcareous sand, extensive undrained monotonic and multi-stage triaxial tests were performed on unreinforced and geogrid reinforced calcareous sand with different relative densities. The test results illustrate that pore pressure generation curves of unreinforced and reinforced calcareous sand gradually evolve from S-shaped to hyperbolic-shaped with the increase in relative density, cyclic stress ratio, and effective confining pressure. Following this, a pore pressure model applicable to both unreinforced and reinforced calcareous sand is proposed. The liquefaction resistance of calcareous sand increases with the increase in relative density, whereas an elevated cyclic stress ratio increases its liquefaction susceptibility. A virtually unique relationship can be observed between the liquefaction resistance normalized to the product of phase transformation strength ratio and relative density against the number of cycles for triggering liquefaction, providing an effective means of early assessing sand liquefaction resistance. Moreover, the geogrid exhibits excellent reinforcement efficiency in enhancing the liquefaction resistance of calcareous sand at relative densities of 50% and 70%. During the post-liquefaction stage, increasing relative density and geogrid reinforcement can accelerate the recovery of stiffness and strength for liquefied calcareous sand and improve the post-liquefaction strength. In general, geogrid reinforcement is considered a good alternative to densification for improving the engineering properties of calcareous sand and offers great application prospects in marine engineering construction. • The effects of geogrid reinforcement and relative density on the liquefaction and post-liquefaction behaviors of calcareous sand are investigated. • A pore pressure model applicable to both unreinforced and reinforced calcareous sand is proposed. • The inclusion of geogrid enhances the liquefaction resistance of calcareous sand. • Increasing relative density and geogrid reinforcement accelerate the recovery of stiffness and strength for liquefied calcareous sand and improve the shear strength during the post-liquefaction stage. • Geogrid reinforcement is considered a good alternative to densification for improving the engineering properties of calcareous sand and offers great application prospects in marine engineering construction. [ABSTRACT FROM AUTHOR]

• Temperature-distributed refrigeration power is transferred from inside a regenerator. • Temperature-distributed transfer coefficient (TTC) increases with discrete points. • Internal DC transfer method eliminates radial thermal resistance and improves TTC. • Combining DC flow and discrete method increases TTC up to 90 %. • TTC of these new methods is 1–2 times higher than previous transfer methods. The temperature-distributed regenerative refrigeration cycle utilizes the real-gas properties to generate the temperature-distributed refrigeration power and improves the cooling performance and liquefaction rate of cryogenic gases. The temperature-distributed refrigeration power is distributed in the volume of the regenerator. It is challenging to transfer this distributed refrigeration power, and the regenerative heat loss is usually inevitable. The transfer process of the temperature-distributed refrigeration power is studied in this paper. A comprehensive investigation into associated influencing factors is presented in this paper. Furthermore, a parameter of the temperature-distributed transfer coefficient (TTC) is proposed to evaluate the transfer process. This study extends into a broader range of the discrete transfer method from liquid-helium temperatures to ambient temperatures and further analyzes the rules from scattered points to multiple points. The internal DC flow method is adopted to eliminate the radial thermal resistance and improve the TTC, recognizing the constraints of the traditional distributed transfer method (coiling heat exchange tubes outside the regenerator). The TTC of the distributed method with the DC flow is improved around 1–2 times by optimizing the mass flux of multi-strand DC flow and temperature range. It is also improved 1.5–2 times by combining the DC flow and discrete method. Additionally, the TTC is improved about 1–1.5 times with the DC flow when using the refrigeration power for gas liquefaction. [ABSTRACT FROM AUTHOR]

Hazelnut shells (HS), scientifically known as Corylus avellana L. shells, are waste produced by companies that process nuts. The main objective of this study was to find an efficient way to maximize the chemical potential of HS by solubilizing the hemicelluloses, which could then be used to recover sugars and, at the same time, increase the lignin content of this material to produce adhesives or high-strength foams. In order to optimize the pre-hydrolysis process, two different temperatures (160 and 170 °C) and times varying from 15 to 180 min were tested. All the remaining solid materials were then liquefied using polyalcohols with acid catalysis. The chemical composition of hazelnut shells was determined before and after the pre-hydrolysis. All of the process was monitored using Fourier Transform Infrared Spectroscopy with Attenuated Total Reflectance (FTIR-ATR) by determining the spectra of solids and liquids after the pre-hydrolysis and liquefaction steps. The highest solubilization of hazelnut shells was found for 170 °C and 180 min, resulting in a 25.8% solubilization. Chemical analysis after the hydrolysis process showed a gradual increase in the solubilization of hemicelluloses as both the temperature and time of the reactor were increased. Simultaneously, the percentages of α-cellulose and lignin in the material also increased with rises in temperature and duration. FTIR-ATR allowed for the detection of significant spectral changes in the hazelnut shells from their initial state to the solid residue and further into the liquefied phase. This confirmed that pre-hydrolysis was effective in enhancing the chemical composition of the material, making it more suitable for the production of adhesives, polyurethane foams, or in the production of bioplastics and composite materials, combined with other biopolymers or synthetic polymers to enhance the mechanical properties and biodegradability of the resulting materials. [ABSTRACT FROM AUTHOR]

The response of a pile embedded in crushable sand subjected to earthquake loading is studied using finite elements. For this purpose, a bounding surface plasticity soil model (SANISAND08) is enhanced to incorporate the grain breakage via the evolution in the critical state line. The adaptive Runge–Kutta–Fehlberg stress integration method is adopted for the numerical implementation of the constitutive model. The model is implemented onto the finite element program as user-defined material. The predictive ability of the enhanced model is examined against the laboratory tests, while the pile response is validated based on the simulation results available in the literature. The effect of particle breakage on the pore water pressure ratio development and consequent changes in bending moment, pile skin friction, and pile settlement is assessed under different earthquake loading scenarios. Simulation results show that particle crushing primarily occurs at the initial stages of seismic excitation, and it escalates pore water pressure, leading to liquefaction susceptibility near the pile. Such a rise in pore water pressure considerably increases pile bending moment and reduces skin friction resistance. [ABSTRACT FROM AUTHOR]

To explore the effects of waste heat (50–170°C) from steel plant flue gas on the column photobioreactor algal liquid temperature for microalgal production, a flue gas‐microalgal liquid heat transfer model was developed that simulated the microalgal growth environment for flue‐gas carbon dioxide (CO2) fixation. The simulation results showed that the influence of high‐temperature flue gas weakened with the increasing microalgal liquid temperature due to enhanced evaporation and heat dissipation. Increasing the flue gas temperature and aeration rate resulted in a higher microalgal liquid temperature up to a maximum increase of 4.16°C at an ambient temperature of 25°C, an aeration rate of 2 L/min, and a flue gas temperature of 170°C. In an experiment on the effect of incubation temperature on the growth rate of microalgae, at an optimal temperature of 35°C, the Chlorella sp. PY‐ZU1 growth rate exhibited a remarkable increase of 104.7% compared to that at 42.5°C. Therefore, modulating the flue gas conditions can significantly increase the microalgal growth rate for CO2 fixation, making it a promising approach to increase biomass production for efficient carbon utilization. [ABSTRACT FROM AUTHOR]

Liquefaction of clean and silty sands remains to be an important problem during earthquakes. Even though many factors are known to influence liquefaction behavior, the influence of density index parameter and fines content (FC) are among the most important parameters. In this study, the effect of relative density (Dr) on liquefaction behavior of clean and silty sands was investigated by cyclic direct simple shear tests on two different silty sands at various FC. Several different relationships affected from Dr are revisited or investigated including number of cycles to liquefaction (NL) and cyclic resistance ratio (CRR). It was found that liquefaction resistance-fines content-relative density relationship is much more complex than previously thought. This is because CRR-Dr lines of clean and/or silty sands may cross each other at specific relative densities, which may cause the liquefaction resistance of a clean sand to be either smaller, equal or greater than the liquefaction resistance of a silty sand with the same base sand dependent on the magnitude of relative density. The mentioned behavior is also confirmed on different clean and silty sands tested in literature. [ABSTRACT FROM AUTHOR]

The present study provides insight into the cyclic behavior of unreinforced and geogrid-reinforced coral sand. To achieve these goals, stress-controlled undrained cyclic triaxial tests were conducted on medium-dense coral sand with and without geogrid reinforcements. The influence of geogrid reinforcement, cyclic stress ratios, and confining pressure on the deformation, pore pressure, liquefaction resistance, stiffness degradation, and particle breakage characteristics of saturated coral sand was investigated. The results indicated that coral sand reinforced with geogrid increased the liquefaction resistance and decreased the rate of pore pressure accumulation. The effectiveness of the geogrid inclusion on coral sand's liquefaction resistance was found to be more pronounced under large effective confining pressure and a smaller cyclic stress ratio. Increasing the effective confining pressure increases the liquefaction resistance for both unreinforced and geogrid-reinforced coral sand, whereas increasing the cyclic stress ratios decreases the liquefaction resistance of the unreinforced and reinforced coral sand. The particle breakage was observed to be increased with increasing the effective confining pressure and cyclic stress ratio, and the breakage was more in the reinforced coral sand than the unreinforced coral sand. [ABSTRACT FROM AUTHOR]

Liquid digestate can be used to provide nutrients for microalgae cultivation but the medium needs to be clear and colorless. The aim of this work was to use liquid digestate from coffee waste biomass to produce a light-permeable medium for microalgae cultivation. A boron-doped diamond anode was applied for electrochemical decolorization of the digestate. The electrochemical oxidation process reduced the platinum-cobalt color value by up to 97% and the chemical oxygen demand by 84.1%. After electrochemical oxidation, 87.4% of the ammonium nitrogen (NH4-N) was retained. Decolorization of the spent coffee grounds liquid digestate was compared with that of dairy cow manure liquid digestate. It took 90 min longer to fully decolorize the spent coffee grounds liquid digestate compared with the dairy cow manure liquid digestate. The boron-doped diamond anode performed better in the decolorization than Ti/IrO2 and Ti/Pt anodes. The effects of the initial Fe2+ concentration and current on the electrochemical oxidation process were also evaluated. Increasing the initial Fe2+ concentration enhanced the Fenton reaction and chemical oxygen demand removal. A higher current enhanced the electrochemical decolorization process and side reactions. Electrochemical oxidation using a boron-doped diamond anode is a promising method for producing an appropriate medium for microalgae cultivation because it promotes decolorization of liquid digestate and retains most of the NH4-N. [ABSTRACT FROM AUTHOR]

With the worldwide awareness of sustainability, biomass-derived carbon electrode materials for supercapacitors have attracted growing attention. In this research, for the first time, we explored the feasibility of making use of the carbon byproduct from hydrothermal liquefaction (HTL) of microalgae, termed herein as algae-derived carbon (ADC), to prepare sustainable carbon electrode materials for high-performance supercapacitor development. Specifically, we investigated carbon activation with a variety of activating reagents as well as N- and Fe-doping of the obtained ADC with the intention to enhance its electrochemical performance. We characterized the structure of the activated and doped ADCs using scanning electron microscope (SEM), Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and BET surface area and pore analysis, and correlated the ADCs' structure with their electrochemical performance as evaluated using cyclic voltammetry (CV), galvanostatic charge/discharge (GCD), impedance, and cycle stability through an assembled symmetric two-electrode cell with 1 M H2SO4 as electrolyte. It was found that the ADC that is activated using KOH (KOH-ADC) showed the best electrochemical performance, and its specific capacitance was 14.1-fold larger with respect to that of the raw ADC and reached 234.5 F/g in the GCD test at a current density of 0.5 A/g. The KOH-ADC also demonstrated excellent capacitance retention (97% after 10,000 cycles at a high current density of 10 A/g) for stable long-term operations. This research pointed out a promising direction to develop sustainable electrode materials for supercapacitors from the carbon byproduct produced after HTL processing of algae. [ABSTRACT FROM AUTHOR]

This article presents multiphase numerical computational fluid dynamics (CFD) for simulating hydrothermal liquefaction of sewage sludge in a continuous plug-flow reactor. The discrete particle method (DPM) was used to analyze the solid particles' interaction in liquid–solid high shear flows to investigate coupling computational fluid dynamics (CFD). Increasing solid particles' interactions were observed with the increasing liquid velocity. The study examined the influence of parameters such as flow rate, temperature, and residence time on the efficiency of bio-oil production. An increase in temperature from 500 to 800 K caused an increase in the amount of biocrude oil produced from 12.4 to 32.9% within 60 min. In turn, an increase in the flow rate of the suspension from 10 to 60 mL/min caused a decrease in the amount of biocrude oil produced from 38.9 to 12.9%. This study offers insights into optimizing the flow channel of tubular reactors to enhance the HTL conversion efficiency of sewage sludge into biocrude oil. A parametric study was performed to investigate the effect of the slurry flow rate, temperature, and the external heat transfer coefficient on the biocrude oil production performance. The simulation data will be used in the future to design and scale up a large-scale HTL reactor. [ABSTRACT FROM AUTHOR]

The proper disposal of antibiotic mycelial residue (AMR) is a critical concern due to the spread of antibiotics and environmental pollution. Pyrolysis emerges as a promising technology for AMR treatment. In this study, we investigated the effect of pyrolysis temperature on the thermal decomposition behavior and product characteristics of avermectin (AV) mycelial residues. Various characterization techniques were employed to analyze thoroughly the compositions and yields of the obtained gas, liquid, and biochar products. The results indicated that most of the organic matter such as protein, carbohydrate, and aliphatic compounds in AV mycelial residues decomposed intensely at 322 °C and tended to end at 700 °C, with a total weight loss of up to 72.6 wt%. As the pyrolysis temperature increased, the biochar yield decreased from 32.81 wt% to 26.39 wt% because of the enhanced degradation of volatiles and secondary reactions of the formed aromatic rings. Accordingly, more gas components were formed with the gas yield increased from 9.76 wt% to 15.42 wt%. For bio-oil, the contents were maintained in the range of 57.43–60.13 wt%. CO and CO2 dominated the gas components with a high total content of almost 62.37–97.54 vol%. At the same time, abundant acids, esters (42.99–48.85%), and nitrogen-containing compounds (32.14–38.70%) such as nitriles, amides, and nitrogenous heterocyclic compounds were detected for the obtained bio-oil. As for the obtained biochars, particle accumulation and irregular pores were presented on their bulk surface, which was primarily composed of calcium oxalate (CaC2O4) and calcium carbonate (CaCO3). This work can provide theoretical insights for the harmless disposal and resource recovery for AMR, contributing significantly to the field of solid waste reuse and management. [ABSTRACT FROM AUTHOR]

To overcome the problem of rapid depletion of natural energy reserves and consequent pollution caused by them, this work explored the possibility of utilizing sewage sludge biomass to produce biooil using hydrothermal liquefaction pathway. In this study, effect of different reaction parameters such as reaction temperature, residence time, and sludge-to-water ratio on solid biomass conversion and bioyield and its higher heating value were investigated. Although maximum conversion of (99.7%) and highest biooil yield (22.01 wt.%) was achieved at 330 °C, however optimum temperature was chosen as 300 °C which produced conversion efficiency and yield of biooil very close (98.07% and 21.5 wt.%, respectively) to what was obtained at 330 °C as lower temperature is beneficial for overall economy of the process. Similarly, a residence time of 60 minutes and sludge-to-water ratio of 1:6 was screened to be producing optimized yield of biooil. The higher heating valu of different fractions biooil was much improved (30.18 MJ/kg of acetone phase and 38.04 MJ/kg of dichloromethane phase) as compared to that of raw feedstock (12.74 MJ/kg). Carbon balance performed on the products indicated that maximum amount of carbon went to biooil phase (53.4 wt.%). However, a significant portion of carbon was lost (33.9 wt.%) due to the limitation of experiments at lab scale which involves evaporation and drying to reach final products. The Fourier transform infrared spectroscopy spectral analysis of different biooil phases showed that it was mainly made up of alcohols, alkane, ketones, aldehydes and carboxylic acids. [ABSTRACT FROM AUTHOR]

The author has proposed the general approach to determining the efficiency ratio of heat-exchange apparatuses with different schemes of motion of the heat-transfer agents on the basis of taking account of their final equilibrium temperature. A procedure has been developed to calculate this temperature for a cocurrent-flow scheme of motion of the heat-transfer agents. The proposed approach makes it possible to consistently determine and to correctly compare the efficiency ratios of heat-exchange apparatuses in counterflow, cocurrent flow, and crossflow of hot and cold heat-transfer agents. The author has given results of calculating the efficiency ratios of heat-exchange apparatuses used in the production of liquefied natural gas. It has been shown that the maximum operating efficiency of a heatexchange apparatus is attained with evaporation of the cold heat-transfer agent (coolant), which is characteristic of the processes of liquefaction of gases. [ABSTRACT FROM AUTHOR]

The influence of anisotropic consolidation on the cyclic liquefaction resistance of granular materials is explored using 3D discrete element method simulations. In this study, the term anisotropic consolidation was defined as the ratio of initial horizontal and vertical normal stresses, and the hypothesis was that the conflicting results from previous laboratory experiments could be attributed to differences in inherent fabric. To test this hypothesis, three unique sample preparation protocols were employed to construct polydisperse spherical particle samples with varying inherent fabrics, as quantified by coordination number and contact-normal fabric anisotropy, under consistent initial mean stress and density conditions. The results were intriguing, as they revealed that anisotropic consolidation had a consistent impact on the cyclic liquefaction resistance of loose and medium-dense samples, regardless of preparation protocol. However, this relationship was not as straightforward in dense samples. In addition, the study assessed the correlations between various parameters, including initial shear wave velocity, state parameters associated with both void ratio and coordination number, fabric anisotropy, and their impact on the cyclic liquefaction resistance of the samples. The findings enhance the understanding of the intricate interplay between anisotropic consolidation and the resistance of granular materials to cyclic liquefaction, providing valuable insights that can inform the development of accurate models for predicting and mitigating cyclic liquefaction in various applications. [ABSTRACT FROM AUTHOR]

This document discusses the importance of catalysts in green technologies for biofuel and bioproduct generation. The use of catalysts is crucial for efficient and sustainable processes that can compete with traditional refineries. The document highlights the requirements for catalysts, such as low cost, compatibility with industrial facilities, positive environmental impact, and high effectiveness and selectivity. It also explores research on innovative alternatives and additives for catalyst production, as well as the development of catalysts for new chemical routes and the implementation of sustainable processes in developing areas. The document provides an overview of published articles that cover various aspects of catalyst use for biofuel and bioproduct generation, including the production of biodiesel and bioenergy from lignocellulosic biomass. The conclusion emphasizes the potential of new catalysts, the importance of stability and durability, and the need for innovative improvements in catalyst technology. [Extracted from the article]

Cold-pressed moringa, milk thistle, and jujube seed oils were investigated in terms of their characteristic profiles, thermal properties, and oxidative stability. The findings proved that the extracted oils were characterized by high nutritional values, which encourages their use in various fields. Results showed significant differences between the obtained oils. Overall, jujube seed oil exhibited the best quality parameters, with acidity equal to 0.762 versus 1% for the moringa and milk thistle seed oils. Milk thistle seed oil showed absorbance in the UV-C (100–290 nm), UV-B (290–320 nm), and UV-A (320–400 nm) ranges, while the moringa and jujube seed oils showed absorbance only in the UV-B and UV-A ranges. Concerning bioactive compounds, jujube seed oil presented the highest content of polyphenols, which promoted a good scavenging capacity (90% at 10 µg/mL) compared to the moringa and milk thistle seed oils. Assessing the thermal properties of the obtained oils showed the presence of four groups of triglycerides in the moringa and milk thistle seed oils, and two groups of triglycerides in the jujube seed oil. The thermograms were constant at temperatures above 10 °C for milk thistle seed oil, 15 °C for jujube seed oil, and 30 °C for moringa seed oil, which corresponded to complete liquefaction of the oils. The extinction coefficients K232 and K270, monitored during storage for 60 days at 60 °C, proved that jujube seed oil had the highest polyphenols content and was the most stable against thermal oxidation. [ABSTRACT FROM AUTHOR]

In seismic-active area, the buried pipeline is subjected to the axial tensile load exceeding the yield stress of pipe material due to the lateral flow induced by soil liquefaction. Designing a girth weld joint that does not fracture at girth weld but base metal which has high elongation capacity is feasible to ensure adequate ground displacement absorbing capacity of the girth weld joint. However, as for fine grain steel, the heataffected zone (HAZ) is softened by welding heat input, and then, the zone of softened HAZ can be the origin of fracture under tensile load. The apparent strength of softened HAZ is affected by the plastic constraint from the surrounding weld metal and base metal during tensile loading, and the fracture location depends on the apparent strength of HAZ. This study investigates the tensile strength and fracture location of girth weld joints with softened HAZ in the static tensile test. The effect of geometric and mechanical heterogeneity of HAZ, strength overmatching of weld metal, and the width-thickness ratio of tensile test specimen on tensile strength are elucidated using parametric finite element analysis. Subsequently, an equation is proposed to predict the tensile strength and fracture location of the welded joint. Using the proposed equation, the condition of geometric and mechanical heterogeneity of the weld to confirm the girth weld joints that fracture at base metal under tensile load is clarified. The proposed equation can be used to design a girth weld joint with liquefaction earthquake resistance. [ABSTRACT FROM AUTHOR]

Biomass liquefaction is an useful technique to realize the high-value conversion and recycling uses of agricultural and forestry waste, as well as for substituting chemical feedstocks. In this paper, the organic solvent liquefaction method was used to liquefy bagasse lignin. The effects of different liquefaction parameters (catalyst dosage, liquid-solid ratio, liquefaction temperature, liquefaction time) on the liquefaction efficiency of bagasse lignin were explored, and its liquefaction products were also characterized. The results showed that the optimized process parameters for liquefaction of bagasse lignin were as follows: the liquefaction temperature was 150, the liquefaction time was 1 h, the liquid-solid ratio was 3:1, the catalyst dosage was 15%, and the residue rate of bagasse lignin was 0.87%. Under the combined action of phenol and sulfuric acid, bagasse lignin was degraded from its original spherical and spherical concave structure into residual particles. The ether bonds and the carbon-carbon bonds connecting the macromolecular structure of bagasse lignin were broken in different ways during the liquefaction process, such as pyrolysis, dehydration, dehydrogenation, deoxygenation, and decarboxylation. Subsequently, small molecular fragments in the liquefied intermediate products rearranged through condensation, hydroxyl methylation, and etherification reactions. Finally, stable and complex mixtures generated, which were soluble in phenol. [ABSTRACT FROM AUTHOR]

Although liquefaction technology has been extensively applied, plenty of biomass remains tainted with heavy metals (HMs). A meta-analysis of literature published from 2010 to 2023 was conducted to investigate the effects of liquefaction conditions and biomass characteristics on the remaining ratio and chemical speciation of HMs in biochar, aiming to achieve harmless treatment of biomass contaminated with HMs. The results showed that a liquefaction time of 1–3 h led to the largest HMs remaining ratio in biochar, with the mean ranging from 84.09% to 92.76%, compared with liquefaction times of less than 1 h and more than 3 h. Organic and acidic solvents liquefied biochar exhibited the greatest and lowest HMs remaining ratio. The effect of liquefaction temperature on HMs remaining ratio was not significant. The C, H, O, volatile matter, and fixed carbon contents of biomass were negatively correlated with the HMs remaining ratio, and N, S, and ash were positively correlated. In addition, liquefaction significantly transformed the HMs in biochar from bioavailable fractions (F1 and F2) to stable fractions (F3) (P < 0.05) when the temperature was increased to 280–330 ℃, with a liquefaction time of 1–3 h, and organic solvent as the liquefaction solvent. N and ash in biomass were positively correlated with the residue state (F4) of HMs in biochar and negatively correlated with F1 or F2, while H, O, fixed carbon, and volatile matter were negatively correlated with F4 but positively correlated with F3. Machine learning results showed that the contribution of biomass characteristics to HMs remaining ratio was higher than that of liquefaction factor. The most prominent contribution to the chemical speciation changes of HMs was the characteristics of HMs themselves, followed by ash content in biomass, liquefaction time, and C content. The findings of this meta-analysis contribute to factor selection, modification, and application of liquefied biomass to reducing risks. [ABSTRACT FROM AUTHOR]

The aim of this study was to assess the influence of thermocompression conditions on lignocellulosic biomasses such as sugarcane bagasse (SCB) in the production of 100% binderless bio-based materials. Five parameters were investigated: pressure applied (7–102 MPa), molding temperature (60–240 °C), molding time (5–30 min), fiber/fine-particle ratio (0/100–100/0) and moisture content (0–20%). These parameters affected the properties and chemical composition of the materials. The density ranged from 1198 to 1507 kg/m3, the flexural modulus from 0.9 to 6.9 GPa and the flexural strength at breaking point from 6.1 to 43.6 MPa. Water absorption (WA) and thickness swelling (TS) values ranged from 21% to 240% and from 9% to 208%, respectively. Higher mechanical properties were obtained using SCB with fine particles, low moisture content (4–10%) and high temperature (≥200 °C) and pressure (≥68 MPa), while water resistance was improved using more severe thermocompression conditions with the highest temperature (240 °C) and time (30 min) or a higher moisture content (≥12.5%). Correlations were noted between the mechanical properties and density, and the material obtained with only fine particles had the highest mechanical properties and density. Material obtained with a 30 min molding time had the lowest WA and TS due to internal chemical reorganization followed by hemicellulose hydrolysis into water-soluble extractables. [ABSTRACT FROM AUTHOR]

Over the past decade, there has been a rapid expansion in the utilisation of process integration for incorporating renewable energy sources and energy storage systems (ESSs). Using different methods to achieve an ESS with higher efficiency is important; the originality of this study arises from two key points: initially, it proposes an inventive arrangement to harness geothermal energy for various purposes and store it in Liquid Hydrogen ( LH 2 ). Additionally, it employs cold energy from a geothermal source through a refrigeration cycle to cool down hydrogen gas prior to its entry into the liquefaction cycle. The proposed multi-generation system uses geothermal energy to produce heat (2.5 kg s - 1 hot water at 60 ℃), fresh water (41 kg s - 1 at 25 ℃), power (5200 kW) and LH 2 (79 kg h - 1 at − 253 ℃), including two-stage instant evaporation, Organic Rankine cycle, internal water heater, proton membrane electrolyser, and reverse osmosis unit. This system is analysed from the point of view of energy, exergy, and economy by focusing on the LH 2 production cycle. GA codes are utilised to optimise the LH 2 production cycle. The total annual cost of 1.74 M$ year−1 including C CAPEX,a (1.46 M$), C OPEX , a (0.25 M$), and C O & M , a (0.03 M$) is calculated for the LH 2 production cycle. Specific liquefaction cost is 2.26 $ kgLH2−1, while the minimum selling price is 2.65 $ kgLH2−1 by considering three years payback period. The LH 2 production cycle has SEC of 8.69 kWh kg Lh 2 - 1 which is less than that of similar small-scale liquefaction processes. [ABSTRACT FROM AUTHOR]

The increasing global population is driving the development of alternative sources of food and energy, as well as better or new alternatives for health and environmental care, which represent key challenges in the field of biotechnology. Microalgae represent a very important source material to produce several high-value-added bioproducts. Due to the rapid changes in the modern world, there is a need to build new materials for use, including those in the nanometer size, although these developments may be chronological but often do not occur at a time. In the last few years, a new frontier has opened up at the interface of biotechnology and nanotechnology. This new frontier could help microalgae-based nanomaterials to possess new functions and abilities. Processes for the green synthesis of nanomaterials are being investigated, and the availability of biological resources such as microalgae is continuously being examined. The present review provides a concise overview of the recent advances in the synthesis, characterization, and applications of nanoparticles formed using a wide range of microalgae-based biosynthesis processes. Highlighting their innovative and sustainable potential in current research, our study contributes towards the in-depth understanding and provides latest updates on the alternatives offered by microalgae in the synthesis of nanomaterials. [ABSTRACT FROM AUTHOR]

Marine microalgae play an increasingly significant role in addressing the issues of environmental monitoring and disease treatment, making the analysis of marine microalgae at the single-cell level an essential technique. For this, we put forward accurate and fast microfluidic impedance cytometry to analyze microalgal cells by assembling two cylindrical electrodes and microchannels to form a three-dimensional detection zone. Firstly, we established a mathematical model of microalgal cell detection based on Maxwell's mixture theory and numerically investigated the effects of the electrode gap, microalgal positions, and ion concentrations of the solution on detection to optimize detection conditions. Secondly, 80 μm stainless steel wires were used to construct flat-ended cylindrical electrodes and were then inserted into two collinear channels fabricated using standard photolithography techniques to form a spatially uniform electric field to promote the detection throughput and sensitivity. Thirdly, based on the validation of this method, we measured the impedance of living Euglena and Haematococcus pluvialis to study parametric influences, including ion concentration, cell density and electrode gap. The throughput of this method was also investigated, which reached 1800 cells per s in the detection of Haematococcus pluvialis. Fourthly, we analyzed live and dead Euglena to prove the ability of this method to detect the physiological status of cells and obtained impedances of 124.3 Ω and 31.0 Ω with proportions of 15.9% and 84.1%, respectively. Finally, this method was engineered for the analysis of marine microalgae, measuring living Euglena with an impedance of 159.61 Ω accounting for 3.9%, dead Euglena with an impedance of 36.43 Ω accounting for 10.1% and Oocystis sp. with an impedance of 55.00 Ω accounting for about 81.0%. This method could provide a reliable tool to analyze marine microalgae for monitoring the marine environment and treatment of diseases owing to its outstanding advantages of low cost, high throughput and high corrosion resistance. [ABSTRACT FROM AUTHOR]

Dynamic loads with different magnitudes cause shear stress and strain in the soil and increase the pore water pressure, reducing soil strength and leading to structural failure. This article presents the behavior of natural river-sand specimens subjected to cyclic loads under both drained and undrained conditions, as observed in cyclic triaxial tests conducted in the laboratory. The experiments were performed on sand specimens with a relative compaction of 0.95 when changing the loading amplitude with three different levels of 30 kPa, 50 kPa and 60 kPa. Experimental results show that, under the condition of drained cycle load, the pore water pressure does not form; only accumulated strain and dynamic parameters are almost unchanged. Meanwhile, with the condition of undrained cyclic load, the pore water pressure increases and causes liquefaction of the specimen, then the axial strain increases dramatically and is not capable of recovery. When varying the loading amplitude under drained condition, the initial-strength values increase as the amplitude of the load increases. This trend has the opposite direction when testing under undrained condition, which means that when increasing the loading amplitude, the initial-strength values decrease and the liquefaction potential of the specimens is faster. Further, under the undrained condition, the loading amplitude of 30 kPa effect is almost negligible on the liquefaction ability of the specimen. [ABSTRACT FROM AUTHOR]

Numerous recent failures of tailings storage facilities (TSFs) (e.g., the 2019 Brumadinho failure in Brazil, the 2018 Cadia failure in Australia) have occurred in the last decade, providing important case histories and lessons to improve the design of TSF facilities. This study is focused on the Cadia TSF failure; specifically, we reexamine and expand the triggering analyses conducted in the forensic study after the failure. In addition, this study also presents the first comprehensive posttriggering and runout assessment of the Cadia failure. The triggering mechanisms were evaluated through Lagrangian-based analyses with the finite-difference method (FDM), which is well suited for small to moderate deformations, whereas the posttriggering mechanisms and runout were evaluated using the material point method (MPM), which is well suited for the evaluation of large deformations. The FDM-based analyses show that the interaction between a relatively weak layer in the foundation [Forest Reef Volcanic Unit A (FRV-A)], the deposited tailings, and the construction of a buttress system is critical in explaining the failure triggering. The MPM-based assessments are useful in investigating posttriggering mechanisms, suggesting a retrogressive failure and stress redistribution occurring within the mine tailings. In addition, the MPM-based assessments also explore the influence of key factors on the posttriggering mechanisms and runout. These factors include the tailings liquefaction extent and strength, the failure propagation rate, the strength of the foundation materials, and the buttress construction. The analyses suggest that the foundation strength, mine tailings liquefaction extent, and buttressing affect the runout assessments significantly. In this context, MPM proves to be especially useful in investigating postfailure conditions. [ABSTRACT FROM AUTHOR]