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As a major source of carbon emissions, the carbon-based power generation industry requires a scientifically robust environmental performance evaluation system to facilitate its green transition and sustainable development. Focusing on unique transition dynamics across four carbon-based power generation formats, this study compares environmental dimension indicators across typical ESG evaluation frameworks and proposes an innovative evaluation index model of environmental performance based on common metrics, with a particular emphasis on their contribution potential to the “Dual Carbon Goals”. The framework’s core innovation lies in its Dual Carbon-focused indicator system, which evaluates three critical indicators overlooked by mainstream ESG methodologies. It extends to include upstream/downstream processes, addressing gaps in current evaluation systems. The findings reveal that core environmental issues, such as climate change, pollution emissions, and resource utilization, exhibit broad commonality in ESG evaluations. Among the assessed indicators, carbon emission intensity carries the highest weight, underscoring its centrality in each power generation sector’s efforts to align with the Dual Carbon Goals. Furthermore, the analysis demonstrates that underground coal gasification combined cycle power generation has a relatively favorable environmental performance, ranking slightly below natural gas combined cycle but above shale gas combined cycle power generation. In contrast, traditional coal-fired power generation exhibits significantly poorer environmental outcomes, highlighting both the efficacy of technological upgrades in reducing emissions and the urgent need for transitioning away from conventional coal-based power. Full article

The construction industry is responsible for 50% of mineral resource extraction and 35% of greenhouse gas (GHG) emissions. In this context, concrete stands out as one of the most consumed materials in the world. More than 30 billion tons of this material are produced annually, resulting in the extraction of around 19.4 billion tons of aggregates (mainly sand and gravel) per year. Therefore, it is urgent to develop strategies that aim to minimize the environmental impacts arising from this production chain. Currently, one of the most widely adopted solutions is the production of concrete through the reuse of construction and demolition waste. Thus, the objective of this research is to conduct a systematic literature review (SLR) on the use of recycled aggregates in concrete production, aiming to increase urban resilience by reducing the consumption of natural aggregates. An extensive search was performed in one of the most respected scientific databases (Scopus), and after a careful selection process, the main articles related to the topic were considered eligible through the PRISMA protocol. The selected manuscripts were then subjected to bibliographic and bibliometric analyses, allowing us to reach the state-of-the-art on the subject. The results obtained on the replacement rates of natural aggregate by recycled aggregate indicate that the recommendations vary from 20 to 60%, and these rates may be higher as long as the recycled aggregate is characterized, and may reach up to 100% as long as the matric concrete has a minimum compressive strength of 60 MPa. The specific gravity of most recycled aggregates ranges from 1.91 to 2.70, maintaining an average density of 2.32 g/cm³. Residual mortar adhered to recycled aggregates ranges from 20 to 56%. The water absorption process of recycled aggregate can vary from 2 to 15%. The mechanical strength of mixtures with recycled aggregates is significantly reduced due to the amount of mortar adhered to the aggregates. The use of recycled aggregates results in a compressive strength approximately 2.6 to 43% lower than that of concrete with natural aggregates, depending on the replacement rate. The same behavior was identified in relation to tensile strength. The modulus of elasticity showed a reduction of 25%, and the flexural strength was reduced by up to 15%. Full article

The outlook for biobased plastics in packaging applications is increasingly promising, driven by a combination of environmental advantages, technological innovation, and shifting market dynamics. Derived from renewable biological resources, these materials offer compelling benefits over conventional fossil-based plastics. They can substantially reduce greenhouse gas emissions, are often recyclable or biodegradable, and, in some cases, require less energy to produce. These characteristics position biobased plastics as a key solution to urgent environmental challenges, particularly those related to climate change and resource scarcity. Biobased plastics also demonstrate remarkable versatility. Their applications range from high-performance barrier layers in multilayer packaging to thermoformed containers, textile fibers, and lightweight plastic bags. Notably, all major fossil-based packaging applications can be substituted with biobased alternatives. This adaptability enhances their commercial viability across diverse sectors, including food and beverage, pharmaceutical, cosmetics, agriculture, textiles, and consumer goods. Several factors are accelerating growth in this sector. These include the increasing urgency of climate action, the innovation potential of biobased materials, and expanding government support through funding and regulatory initiatives. At the same time, consumer demand is shifting toward sustainable products, and companies are aligning their strategies with environmental, social, and governance (ESG) goals—further boosting market momentum. However, significant challenges remain. High production costs, limited economies of scale, and the capital-intensive nature of scaling biobased processes present economic hurdles. The absence of harmonized policies and standards across regions, along with underdeveloped end-of-life infrastructure, impedes effective waste management and recycling. Additionally, consumer confusion around the disposal of biobased plastics—particularly those labeled as biodegradable or compostable—can lead to contamination in recycling streams. Overcoming these barriers will require a coordinated, multifaceted approach. Key actions include investing in infrastructure, advancing technological innovation, supporting research and development, and establishing clear, consistent regulatory frameworks. Public procurement policies, eco-labeling schemes, and incentives for low-carbon products can also play a pivotal role in accelerating adoption. With the right support mechanisms in place, biobased plastics have the potential to become a cornerstone of a sustainable, circular economy. Full article

Deep shale gas reservoirs are vital sources of unconventional natural gas and present unique challenges for exploration and development due to their multiscale flow characteristics and elastoplastic deformation behavior of reservoir rocks. Accurately predicting permeability in these reservoirs is crucial. This study introduces a novel model utilizing fractal theory and a thick-walled cylinder model to characterize stress-dependent apparent gas permeability. The model incorporates various flow mechanisms, including viscous flow, transition flow, Knudsen diffusion, surface diffusion, real gas effects, and gas slip effects. It enables predictions of how permeability changes with elastoplastic behavior and affects the pore volume fractions of different flow mechanisms. Experimental validation during elastic and elastoplastic deformations confirms the model’s accuracy, with each parameter having clear physical significance. Key findings reveal that, at the same effective stress, apparent gas permeability increases with pore radius fractal dimension, temperature, and Young’s modulus, while decreasing with capillary tortuosity fractal dimension. Additionally, during plastic deformation, greater magnitudes of plastic strain lead to more pronounced changes in apparent gas permeability compared to elastic deformation. These insights emphasize the importance of incorporating elastoplastic behavior in studies of deep shale gas reservoirs. Full article

In this study, a 3D model is developed to simulate multi-hole leakage scenarios in buried pipelines transporting hydrogen-blended natural gas (HBNG). By introducing three parameters—the First Dangerous Time (FDT), Ground Dangerous Range (GDR), and Farthest Dangerous Distance (FDD)—to characterize the diffusion hazard of the gas mixture, this study further analyzes the effects of the number of leakage holes, hole spacing, hydrogen blending ratio (HBR), and soil porosity on the diffusion hazard of the gas mixture during leakage. Results indicate that gas leakage exhibits three distinct phases: initial independent diffusion, followed by an intersecting accelerated diffusion stage, and culminating in a unified-source diffusion. Hydrogen exhibits the first two phases, whereas methane undergoes all three and dominates the GDR. Concentration gradients for multi-hole leakage demonstrate similarities to single-hole scenarios, but multi-hole leakage presents significantly higher hazards. When the inter-hole spacing is small, diffusion characteristics converge with those of single-hole leakage. Increasing HBR only affects the gas concentration distribution near the leakage hole, with minimal impact on the overall ground danger evolution. Conversely, variations in soil porosity substantially impact leakage-induced hazards. The outcomes of this study will support leakage monitoring and emergency management of HBNG pipelines. Full article

Peat soil is a significant global carbon storage pool, accounting for one-third of the global soil carbon pool. Its greenhouse gas emissions have a significant impact on climate change. Seasonal freeze–thaw cycles are common natural phenomena in high-latitude and high-altitude regions. They significantly affect the mineralization of soil organic carbon and greenhouse gas emissions by altering the physical structure, moisture conditions, and microbial communities of the soil. In this study, through the construction of an indoor simulation experiment of the typical freeze–thaw cycle models in spring and autumn in the Greater Xing‘an Range region of China and the Jinchuan peatland of Jilin Longwan National Nature Reserve, the physicochemical properties, greenhouse gas emission fluxes, microbial community structure characteristics, and key metabolic pathways of peat soils in permafrost and seasonally frozen ground areas were determined. The characteristics of greenhouse gas emissions and their influencing mechanisms for peat soil in northern regions under different freeze–thaw conditions were explored. The research found that the freeze–thaw cycle significantly changed the chemical properties of peat soil and significantly affected the emission rates of CO₂, CH₄, and N₂O. It also clarified the interaction relationship between soil’s physicochemical properties (such as dissolved organic carbon (DOC), dissolved organic nitrogen (DON), ammonium nitrogen (NH₄⁺), soil organic carbon (SOC), etc.) and the structure and metabolic function of microbial communities. It is of great significance for accurately assessing the role of peatlands in the global carbon cycle and formulating effective ecological protection and management strategies. Full article

To accommodate the extreme thermodynamic effects and erosion damage in throttling equipment for ultra-high-pressure natural gas wells (175 MPa), a coupled multiphase flow erosion numerical model for nozzles was established. This model incorporates a real gas compressibility factor correction and is based on the renormalized k-ε RNG (Renormalization Group k-epsilon model, a turbulence model that simulates the effects of vortices and rotation in the mean flow by modifying turbulent viscosity) turbulence model and the Discrete Phase Model (DPM, a multiphase flow model based on the Eulerian–Lagrangian framework). The study revealed that the nozzle flow characteristics follow an equal-percentage nonlinear regulation pattern. Choked flow occurs at the throttling orifice throat due to supersonic velocity (Ma ≈ 3.5), resulting in a mass flow rate governed solely by the upstream total pressure. The Joule–Thomson effect induces a drastic temperature drop of 273 K. The outlet temperature drops below the critical temperature for methane hydrate phase transition, thereby presenting a substantial risk of hydrate formation and ice blockage in the downstream outlet segment. Erosion analysis indicates that particles accumulate in the 180° backside region of the cage sleeve under the influence of secondary flow. At a 30% opening, micro-jet impact causes the maximum erosion rate to surge to 3.47 kg/(m²·s), while a minimum erosion rate is observed at a 50% opening. Across all opening levels, the maximum erosion rate consistently concentrates on the oblique section of the plunger front. Results demonstrate that removing the front chamfer of the plunger effectively improves the internal erosion profile. These findings provide a theoretical basis for the reliability design and risk prevention of surface equipment in deep ultra-high-pressure gas wells. Full article

Shale pore architecture governs gas storage capacity, permeability, and production potential in reservoirs. Therefore, this study systematically investigates the pore structure features and influencing factors of the Niutitang Formation shale from the QX1 well in northern Guizhou using field emission scanning electron microscopy (FE-SEM), high-pressure mercury intrusion (HPMI), low-temperature nitrogen adsorption (LTNA), and nuclear magnetic resonance (NMR) experiments. The results show that ① The pore size of the QX1 well’s Niutitang Formation shale is primarily in the nanometer range, with pore types including intragranular pores, intergranular pores, organic matter pores, and microfractures, with the former two types constituting the primary pore network. ② Pore shapes are plate-shaped intersecting conical microfractures or plate-shaped intersecting ink bottles, ellipsoidal, and beaded pores. ③ The pore size distribution showed a multi-peak distribution, predominantly mesopores, followed by micropores, with the fewest macropores. ④ The fractal dimension D₁ > D₂ indicates that the shale pore system is characterized by a rough surface and some connectivity of the pore network. ⑤ Carbonate mineral abundances are the main controlling factors affecting the pore structure of shales in the study area, and total organic carbon (TOC) content also has some influence, while clay mineral content shows negligible statistical correlation. Full article

The methane flux in the Dongsha area in the northern South China Sea is relatively high. The results indicate the presence of both shallow and deep gas hydrate reservoirs at the Site DS-W08. The gas hydrate reservoir in this area is mainly composed of fine-grained sediments, and high-saturation gas hydrates are present. The shallow-GHR (8–24 mbsf) exhibits a maximum hydrate saturation of 14% (pore volume). The deep-GHR (below 65 mbsf) shows a maximum hydrate saturation of 33% The suspended sedimentation process on the banks of turbidity currents and the deep-water traction current sedimentation process play potentially important roles in the enrichment of gas hydrates. To investigate the influence of sedimentary processes on gas hydrate accumulation, this study analyzed gas hydrate saturation, sediment grain size, grain compositions, biological components, and geochemical characteristics of hydrate-bearing and adjacent layers at Site DS-W08. Sediment grain size analysis suggests that the studied layer was formed through the interaction of turbidity current-induced overbank suspended deposition and traction current deposition. By comprehensively analyzing the comparison of sediment Sr/Ba ratios and the data of foraminifera and calcareous nannofossils, it is found that the bank deposits and traction current deposits triggered by turbidity currents correspond to glacial periods and interglacial periods, respectively. Analysis of biological components shows that layers with high foraminifera content and traction current-modified sediments are more favorable for gas hydrate accumulation. Hydrate reservoirs are all composed of traction current deposits, and the cap rock rich in foraminifera fossils at the top promotes hydrate formation; while the fine-grained turbidites formed during the turbidite deposition process inhibit hydrate accumulation. This study aims to deepen the understanding of the enrichment mechanism of natural gas hydrates and support the commercial development of fine-grained sediments in the northern South China Sea. Full article

Boron is frequently present in saline water (e.g., seawater, geothermal water, and hydrocarbon production water) due to the natural release of boric acid from minerals. While essential to life, excess boron is toxic, particularly to citrus plants, necessitating its regulation for safe water use. Current boron removal methods, such as reverse osmosis, chelating resin adsorption, and magnesium-based precipitation softening, increase water treatment complexity and cost. Ettringite, (Ca₆Al₂(SO₄)₃(OH)₁₂·26H₂O), is a clay and an effective anion adsorbent. It is also a key hydration product of Portland cement. This study explores boron removal via precipitation softening using sulfoaluminate clinker as an ettringite precursor. Raw water, a first-stage reverse-osmosis permeate from an Italian oil-and-gas site, contained approximately 15.0 mg/L of boron. Optimal removal required sulfoaluminate clinker in excess with respect to the stoichiometric dose and 150 min of contact time. The preliminary results demonstrate the feasibility of this approach, offering a viable alternative to existing methods. Full article

In the context of the current global transition toward low-carbon energy, the issue of $C{O}_2$ utilization has become increasingly important. One of the most promising natural targets for $C{O}_2$ sequestration is the terrigenous sedimentary formations found in oil, gas, and coal basins. It is generally assumed that $C{O}_2$ injected into such formations can be stored indefinitely in a stable form. However, the dissolution of $C{O}_2$ into subsurface water leads to a reduction in pH, which may cause partial dissolution of the host formation, altering the structure of the subsurface in the injection zone. This process is relatively slow, potentially unfolding over decades or even centuries, and its long-term consequences require careful investigation through mathematical modeling. The geological formation is treated as a partially soluble porous medium, where the dissolution rate is governed by surface chemical reactions occurring at the pore boundaries. In this study, we present an applied mathematical model that captures the coupled processes of mass transport, surface chemical reactions, and the resulting microscopic changes in the pore structure of the formation. To ensure the model remains grounded in realistic geological conditions, we based it on exploration data characterizing the composition and microstructure of the pore space typical of the Cenomanian suite in northern Western Siberia. The model incorporates the dominant geochemical reactions involving calcium carbonate (calcite, $CaC{O}_3$), characteristic of Cenomanian reservoir rocks. It describes the dissolution of $C{O}_2$ in the pore fluid and the associated evolution of ion concentrations, specifically $H^{+}$, $C{a}^{2+}$, and $HC{O}_3^{-}$. The input parameters are derived from experimental data. While the model focuses on calcite-based formations, the algorithm can be adapted to other mineralogies with appropriate modifications to the reaction terms. The simulation domain is defined as a cubic region with a side length of 1 $\mathsf{\mu }$m, representing a fragment of the geological formation with a porosity of 0.33. The pore space is initially filled with a mixture of liquid $C{O}_2$ and water at known saturation levels. The mathematical framework consists of a system of diffusion–reaction equations describing the dissolution of $C{O}_2$ in water and the subsequent mineral dissolution, coupled with a model for surface evolution of the solid phase. This model enables calculation of surface reaction rates within the porous medium and estimates the timescales over which significant changes in pore structure may occur, depending on the relative saturations of water and liquid $C{O}_2$. Full article

The neural architecture search technique is used to automate the engineering of neural network models. Several studies have applied this approach, mainly in the fields of image processing and natural language processing. Its application generally requires very long computing times before converging on the optimal architecture. This study proposes a hybrid approach that combines transfer learning and dynamic search space adaptation (TL-DSS) to reduce the architecture search time. To validate this approach, Long Short-Term Memory (LSTM) models were designed using different evolutionary algorithms, including artificial bee colony (ABC), genetic algorithm (GA), differential evolution (DE), and particle swarm optimization (PSO), which were developed to predict trends in global horizontal irradiation data. The performance measures of this approach include the performance of the proposed models, as evaluated via RMSE over a 24-h prediction window of the solar irradiance data trend on one hand, and CPU search time on the other. The results show that, in addition to reducing the search time by up to 89.09% depending on the search algorithm, the proposed approach enables the creation of models that are up to 99% more accurate than the non-enhanced approach. This study demonstrates that it is possible to reduce the search time of a neural architecture while ensuring that models achieve good performance. Full article

Water-use efficiency (WUE) plays a crucial role in sustainable crop production, particularly in water-limited environments where maximizing natural resource use is essential. This study evaluated the physiological and agronomic performance of two Piper nigrum cultivars, Clonada and Uthirankotta, grown under different soil water potential conditions. The trial was conducted in a 1930 m² field using a randomized block design and drip irrigation system, calibrated to 3.55 L h⁻¹ with a uniformity of 97%. Soil water availability was managed based on daily tensiometer readings at 20 and 30 cm depths, triggering irrigation at defined tensions (10–55 kPa). Clonada exhibited higher net CO₂ assimilation rates (A) and stomatal conductance (g_s), but these responses did not lead to higher yields. In contrast, Uthirankotta consistently maintained superior water-use efficiency and yield across all soil moisture conditions by favoring water conservation and targeted biomass allocation over maximized gas exchange. Both cultivars performed optimally at a soil water potential range of 25–35 kPa, with declines in yield and gas exchange parameters at higher tensions (45–55 kPa). Under such conditions, Uthirankotta was 51.3% more water-use efficient and 40.8% more productive than Clonada. Based on this, a Principal Component Analysis (PCA) further demonstrated distinct physiological profiles, underscoring trade-offs between yield and water-use strategies. These results highlight the significance of cultivar selection for optimizing WUE and provide valuable insights into irrigation management and breeding programs aimed at boosting black pepper performance under water-limited conditions. Full article

During drilling operations, lost circulation frequently occurs, leading to significant loss of drilling fluids which causes environmental damage and increasing drilling costs. To address the problem of fracture plugging, gel materials have emerged as an ideal solution due to stable physicochemical properties and excellent environmental compatibility. However, most existing gels exhibit poor stability and low mechanical strength under high-temperature conditions. To overcome these limitations, high-temperature-resistant phase-conversion stiffened dual-network hydrogel for oil-based drilling fluids was developed. Phase-conversion was realized by immersing synthesized double-network hydrogel in ethylene glycol (EG), polyethylene glycol (PEG), and glycerol (Gly), optimizing and enhancing its mechanical properties, followed by plugging performance evaluations. Experimental results demonstrated that the phase-conversion stiffened gels achieved significantly improved compressive strength and plugging efficiency at elevated temperature. The GC-MS results indicated that dehydration and reagent exchange occurred during immersion, with change in the solid content of the sample. After being treated by white oil at high temperature, the oil phase almost replaced the water phase in the gel. The results of ATR-IR confirmed the formation of hydrogen bonds in the gel. TGA data revealed that PEG enhanced the thermal stability of the gel, EG negatively affected thermal stability, and Gly had negligible influence. The enhancement in gel strength primarily stems from the increase in solid content caused by phase transformation. Dehydration and multiple hydrogen bonds formed between organic reagent molecules and polymer chains in the gel have a synergistic enhancement effect. Full article

To meet the high standards required for the liquefaction process by the Floating Liquefied Natural Gas System (FLNG), including low power consumption, compact footprint, high safety, resistance to waves, and portability, this paper proposes a novel FLNG liquefaction process which combines the supersonic swirling separation technology with pressurized liquefaction technology. The process is simulated and optimized using Aspen HYSYS V10 software and genetic algorithms. The results indicate that the specific power consumption of this liquefaction process is only 0.208 kWh/m³, with the cooler, expander, and compressor being the main equipment responsible for exergy losses, accounting for 28.85%, 26.48%, and 21.70%, respectively. This liquefaction process is relatively adaptable to changes in feed gas pressure, temperature, and methane content. The specific power consumption slightly increases with the increasing feed gas pressure and temperature, while it exhibits some fluctuations with the increasing methane content. The process requires a low CO₂ removal rate, possesses moisture pretreatment capability, has fewer pieces of equipment, and saves a significant amount of valuable space. It combines low specific power consumption, minimal impact from swaying, and high safety, providing considerable application potential in future offshore natural gas development. Full article