Search Results (268)

Geopolitical disruptions of natural gas supply have repeatedly forced importing countries to reorganize their electricity systems, yet it remains unclear whether such disruptions are followed by movement of structurally different economies toward comparable energy-security and sustainability outcomes. This study compares Germany, a high-income economy exposed to the 2022 curtailment of Russian pipeline gas, with Jordan, a developing import-dependent economy exposed to the repeated sabotage of the Arab Gas Pipeline after 2011, using harmonized generation-mix and carbon intensity data for Germany over 1985–2024 and Jordan over 2000–2022, supplemented by weekly German market data. The generation fuel mix concentration is measured with a Herfindahl-based Supply Concentration Index (SCI), structural change is estimated with segmented interrupted time series (ITS) regressions inferred through Newey–West heteroskedasticity- and autocorrelation-consistent standard errors, and the joint security–sustainability position of each country is summarized with a newly proposed Energy Vulnerability–Transition Index (EVTI) that combines diversification, renewable penetration, and carbon intensity performance. The results show that Jordan’s 2011 disruption was associated with a baseline estimated change in its carbon intensity trajectory from +3.32 to −12.63 gCO₂/kWh per year and with renewable growth of +2.39 percentage points per year from a near-zero base, while Germany’s 2022 disruption was associated with a temporary carbon intensity shock, visible in a coal reactivation index that peaked at 1.26 and a sixfold wholesale price increase, followed by a policy-supported return to the pre-existing decarbonization pathway. The Germany–Jordan EVTI ratio narrowed from 6.5× in 2014 to 1.8× in 2022, and this convergence is robust to alternative component weightings. The findings indicate that geopolitical gas disruptions, despite their high short-run costs, were followed in both contexts by measurable movement toward more diversified and lower-carbon electricity systems, with direct implications for Sustainable Development Goal (SDG) 7. Full article

Wuyi rock tea (WRT) processed from dew-soaked leaves is often characterized by a pronounced grassy off-odor defect. However, the key odor-active compounds and their potential underlying mechanisms remain unclear. In this study, quantitative descriptive sensory analysis, GC–MS, GC–O, molecular docking, and aroma addition tests were used to systematically elucidate the chemical basis and potential perceptual mechanisms of the key grassy off-odor in WRT processed from dew-soaked leaves. The results showed that 16 volatile compounds were significantly associated with dew, among which (E,E)-2,4-heptadienal, octanal, hexanal, and heptanal were identified as the major odor-active compounds responsible for the grassy off-odor. The accumulation of these aldehydes may be associated with lipid peroxidation under the influence of dew. Aroma addition and omission tests confirmed that (E,E)-2,4-heptadienal contributed significantly to grassy off-odor formation and that additive effects existed among the four compounds. Molecular docking predicted that the four key odor-active compounds interacted with human olfactory receptors, including OR1A1 and OR10J5, through hydrogen bonds and hydrophobic interactions, thereby affecting grassy off-odor perception, with predicted binding energies below −4.7 kcal/mol. This study elucidated the effects of dew on the formation of the characteristic aroma of WRT and provides a scientific basis for tea quality regulation and processing improvement. Full article

Liupao tea (LPT), one of China’s representative fermented dark teas, develops its unique “red, heavy, aged, and mellow” flavor characteristics. This review provides a comprehensive update on LPT aroma, integrating analyses of volatile organic compounds (VOCs), associated microorganisms, odor-active compounds (OACs), and metabolic pathways of key odor-active compounds (KOACs). With over 2000 VOCs documented, predominated by alcohols (368), hydrocarbons (357), and ketones (351), the total for LPT substantially exceeds the approximately 1000 compounds typically reported for other dark teas. By combining sensory evaluation with techniques such as gas chromatography–olfactometry (GC-O) and odor activity value (OAV), KOACs, predominantly comprising alcohols, aldehydes, and methoxybenzene derivatives, were identified as key contributors to the floral, fruity, aged, stale and other notes that define LPT’s characteristic aroma. The formation of the aroma compounds is closely linked to microbial metabolism and the enzymatic activities generated by microorganisms. Fungi, including Aspergillus, Rhodotorula, Geosmithia, Wallemia, Penicillium, Blastobotrys, Fusarium, and Xeromyces, and bacteria, including Burkholderia, Ralstonia, and Achromobacter, serve as the primary functional microorganisms driving fermentation and aging. This review provides a comprehensive framework for understanding the chemical and microbial complexity of LPT aroma. Full article

Fuel cells (FCs) are critical for decarbonizing the transport industry, with Life Cycle Assessment (LCA) serving as the standard evaluation framework. However, existing literature exhibits severe methodological heterogeneities and divergent system boundaries that introduce deep epistemic uncertainties. This review conducts a systematic analysis to critically harmonize FC environmental performance across the road, aviation, and maritime sectors. Quantitative synthesis reveals global warming potential (GWP) as the dominant metric. For light-duty vehicles, GWP drops to around 30 gCO₂eq/km, matching battery-electric configurations exclusively under deeply decarbonized grids. Manufacturing FC stacks and advanced storage imposes a severe upfront carbon debt, particularly prominent in heavy-duty freight (60–130 tCO₂eq). In aviation, 80–90% in-flight GWP reductions trigger massive burden-shifting, transferring 60–70% of lifecycle damages to ground-based infrastructure. Maritime FCs shrink GWP to 0.06–0.60 kgCO₂eq/kWh, strictly contingent on upstream hydrogen production. Crucially, despite long-term GWP advantages, FC pathways face systematic penalties in acidification, eutrophication, and ecotoxicity, heavily driven by platinum-group catalysts and fluoropolymer membranes. By isolating software-driven biases and database discrepancies, this work delivers an actionable methodological roadmap, establishing a policy-aligned baseline for future FC transportation sustainability frameworks. Full article

Conventional cement-based grouts used to stabilize fractured rock slopes and fill large cavities are heavy, carbon-intensive, and can impose excessive dead load on weakened rock masses. This study addresses these limitations by integrating bio-based rigid polyurethane—particularly castor oil-based polyurethane—into a slag-based geopolymer mortar, producing a lightweight, low-permeability, rock-adherent alternative grouting system. Three formulations were evaluated: unmodified geopolymer grout (GG), geopolymer grout modified with petroleum-based polyurethane (G-PUG), and geopolymer grout modified with castor oil-based polyurethane (GCO-PUG). Materials were characterized using infrared spectroscopy, thermogravimetric analysis (TGA), X-ray diffraction, and scanning electron microscopy with energy-dispersive X-ray spectroscopy, and tested for apparent density, permeability, unconfined compressive strength, and direct shear behavior—including at the grout–limestone interface using rock sourced from El-Mokattam plateau, Cairo. Polyurethane incorporation reduced apparent density by up to 24% (from 22.15 to 16.89 kN/m³) and permeability to as low as 2.3 × 10⁻⁸ m/s, at the cost of a substantial reduction in compressive strength (from 5564 to 139 kN/m²). The castor oil-based grout also showed improved rock adhesion, with interfacial cohesion increasing by 67% relative to its standalone state. Accordingly, unmodified GG is recommended for high-load structural applications, whereas GCO-PUG provides a lightweight, low-permeability, and strongly rock-adherent alternative for filling large cavities and stabilizing slopes under moisture-sensitive and weight-critical conditions, where reducing self-weight and limiting water ingress are more important than achieving maximum compressive strength. Full article

This study investigates the performance, energy flow, efficiency, and environmental impact of a C-segment battery electric vehicle (BEV). As BEVs are increasingly considered a sustainable alternative to conventional internal combustion engine vehicles, a detailed understanding of their energy utilization and operational emissions is essential. A MATLAB/Simulink-based vehicle model incorporating an 88.5 kWh battery pack, a 160 kW permanent magnet synchronous motor (PMSM), regenerative braking, and longitudinal vehicle dynamics was developed. The developed model was validated by comparing the simulated vehicle performance characteristics with the publicly available specifications and performance data of the reference TOGG T10F vehicle. The vehicle was evaluated under the WLTP Class 3 driving cycle, while the effects of aggressive and high-speed driving conditions were further investigated using the US06 and Artemis Motorway 150 cycles. The results indicate a net vehicle energy consumption of 136.4 Wh/km and a driving range of 623 km under WLTP conditions. The PMSM achieved average efficiencies of 93.4% in traction mode and 92.7% in regenerative braking mode, while the cumulative battery-to-wheel drivetrain efficiency reached 81.5%. In addition, approximately 19.9% of the consumed energy was recovered through regenerative braking. Vehicle emissions were also assessed using different electricity generation mixes based on the rated energy consumption, including charging losses, yielding operational emissions between 27.7 and 116.0 gCO₂e/km. The findings demonstrate that the developed model provides realistic performance predictions and confirm the potential of BEVs to achieve high efficiency and substantially lower emissions than conventional passenger vehicles. Full article

Digital transformation is a key initiative to promote corporate sustainability. However, in the absence of unified information disclosure standards and effective verification mechanisms, the digital transformation information disclosed by firms may not fully reflect their actual progress in transformation. This paper focuses on the relative discrepancy between the digital transformation information disclosed by firms and their actual level of digital transformation. It constructs a catering index for information disclosure using China’s A-share listed companies from 2015 to 2024 and empirically examines the impact of this disclosure and related catering behavior on corporate sustainability performance. The study finds that digital transformation information disclosure (DIG) significantly enhances corporate sustainability performance (CSP), with green collaborative innovation (GCO) partially mediating this effect. Catering behavior (Cater) negatively moderates the relationship between digital transformation information disclosure and corporate sustainability performance and weakens the mediating effect of green collaborative innovation. Heterogeneity analysis shows that the negative moderating effect of catering behavior (Cater) is more pronounced in non-state-owned enterprises, small-sized enterprises, industries with low environmental sensitivity, and low competitive industries. This study provides a basis for identifying the consistency between corporate digital transformation disclosure and actual transformation progress and offers valuable references for standardizing disclosure practices, promoting green collaborative development, and enhancing corporate sustainability performance. Full article

To investigate the influence of manufacturing process on the flavor of Chinese dark tea, the volatile profiles of five varieties (Fuzhuan, Pu-erh, Liubao, Bailiang, and Tianjian) were analyzed using gas chromatography–mass spectrometry/olfactometry (GC-MS/O). A total of 178 volatile compounds were identified by GC-MS, among which linalool and its oxides were the most abundant aroma-active components, particularly in Pu-erh tea, which underwent the longest fermentation. GC-O analysis revealed 11 compounds with relative odor activity values (ROAVs) greater than 1, including β-gulonic aldehyde, (E,Z)-2,6-nonadienal, β-isopropenyl, (Z)-4-hexenal, 3-methylbutanal, (E,Z)-2,4-decadienal, (E,E)-2,4-decadienal, hexanal, linalool, and (R/Z)-linalool oxide. These were considered the key aroma-active compounds contributing to the overall aroma of dark tea. Principal component analysis further indicated that the distinctive woody and aged notes of Pu-erh tea were associated with linalool, (E/Z)-linalool oxide, 1,2,3-trimethylbenzene, β-gulonic aldehyde, benzaldehyde, and citronellol. In contrast, α/β-ionone and a series of fatty acid derivatives such as (E,Z)-2,6-nonadienal, (Z)-4-heptenal, (E,Z)-2,4-dodecadienal, (E,E)-2,4-dodecadienal, and hexanal were mainly responsible for sweet, grassy, and herbal notes. These substances are particularly prominent in Fuzhuan and Bailiang teas. Our findings demonstrate that processing techniques significantly affect the aroma quality of dark tea, providing a valuable reference for variety discrimination and process optimization. Full article

Expanding university campuses face a dual challenge: meeting higher internal travel demand while reducing congestion and emissions. Using stated-preference data (412 respondents; 9 choice tasks per person), this study quantifies the expected adoption of two low-emission micromobility options—bicycle and electric scooter—relative to walking and car for intra-campus trips at an Ecuadorian university. Under Random Utility Theory, we estimate a multinomial logit (MNL) and a panel mixed logit (MIXL) model, treating MIXL as the preferred specification. Simulated maximum likelihood with 12,000 draws shows MIXL substantially improves fit and reveals marked heterogeneity in time sensitivity. In out-of-sample prediction (TEST), the two prospective modes achieve comparable average choice probabilities (bicycle = 0.289; electric scooter = 0.286), with a joint acceptance of 0.575, supporting the feasibility of a micromobility program under the evaluated scenarios. Environmental impact (gCO₂/km) exhibits limited aggregate influence compared with operational factors (time and cost). A complementary WTP-space MIXL provides VOT estimates and confirms that 10–20% time reductions increase expected acceptance. Overall, results indicate that adoption is most likely when sustainability objectives are translated into tangible service improvements in effective speed, reliability, and affordability. Full article

To address the challenges in maize leaf disease detection, including large variation in lesion scales, weak texture of small targets, strong background interference, limited recall ability for blurred lesions, and computational redundancy of conventional detection heads, this paper proposes a lightweight detection algorithm based on an improved YOLOv11n. First, a multi-scale global context kernel attention module is designed, which employs GCKA-bottleneck with large-kernel attention and residual connections to enhance the deep semantic representation of multi-scale lesions. Second, a GSConv-enhanced coordinate multi-receptive attention module is constructed, which combines coordinate position awareness and multi-scale depthwise convolution. Finally, a regression-enhanced depthwise-separable decoupled detection head is proposed to decouple classification and regression tasks, and introduces depthwise separable convolution and a distributed bounding box regression. On a public dataset containing four classes, the improved model achieves an mAP@0.5 of 85.36%, a recall of 83.32%, and a precision of 86.91%, which are 3.46, 27 2.94, and 2.38 percentage points higher than those of the original YOLOv11n, respectively. Meanwhile, GFLOPs and parameter count are reduced by 27.0% and 12.4%, respectively. The proposed algorithm strikes a favorable balance between accuracy, real-time performance, and lightweight design, providing a feasible technical support for field deployment in intelligent agricultural disease monitoring systems. Full article

Background: Genetic testing is increasingly part of the diagnostic pathway of congenital hearing loss (CHL), clarifying etiology and supporting clinical management. However, its psychosocial impact, especially differences between syndromic and non-syndromic conditions, remains underexplored. Objectives: This study evaluated the differential psychological impact of genetic diagnosis in syndromic versus non-syndromic pediatric patients, its relationship with clinical and rehabilitative variables, and the role of post-diagnostic psychological assessment. Methods: A cross-sectional post-diagnosis survey was conducted in families of children with genetically confirmed syndromic (Usher syndrome, n = 21) and non-syndromic (GJB2-related, n = 21) CHL; a total of 37 families responded. Parental empowerment was assessed using an Italian translated version of the Genetic Counseling Outcome Scale (GCOS-24). In an exploratory analysis, GCOS-24 items were grouped into three author-derived domains (understanding/awareness, emotional experience, and informational support) based on semantic content, not validated psychometrically. Results: No significant differences in GCOS-24 scores emerged between groups, nor in relation to clinical variables like hearing loss severity, auditory outcomes, or rehabilitative interventions. Genetic diagnosis occurred later in the syndromic group. Qualitative observations suggested parental empowerment varied with timing of diagnosis, clarity of information, and therapeutic alliance quality. Conclusions: Overall, these results highlight the importance of integrating psychological support and structured communication into clinical pathways to support families and patients in understanding and adapting to the diagnosis over time. Further longitudinal studies are needed to clarify the evolving psychosocial impact of genetic diagnosis in CHL. Full article

The role of internal combustion engines in future transport systems is expected to remain central, particularly in hard-to-abate sectors such as heavy-duty road transport and maritime applications. However, their decarbonization requires the adoption of low-carbon and renewable fuels. This review examines hydrogen, methane-based fuels, methanol, and ethanol for internal combustion engine applications using a pathway-based approach that integrates life-cycle assessment, technology readiness level, commercial readiness level, and engine-related considerations. The reviewed literature shows that the environmental performance of these fuels varies strongly depending on feedstock, production pathway, process configuration, and energy source. From a Well-to-Tank perspective, hydrogen pathways exhibit particularly large variability, ranging from around 3 gCO₂eq/MJ for wind-based electrolysis to around 230 g CO₂eq/MJ for coal gasification. Methane-based fuels range from around 16 gCO₂eq/MJ for fossil compressed and liquefied natural gas to negative values for waste- and manure-based biomethane. Methanol and ethanol also show substantial variability, with renewable, waste-derived, and bio-based pathways generally offering substantially lower life-cycle greenhouse gas (GHG) emissions than fossil-based routes. In the use phase, Tank-to-Wheel analysis shows that energy demand remains relatively similar across fuels, while differences in direct emissions are mainly related to fuel carbon content and other GHG species such as ${\mathrm{CH}}_4$ or ${\mathrm{H}}_2$ slip and combustion-related species such as ${\mathrm{N}}_2\mathrm{O}$. The Well-to-Wheel comparison for heavy-duty applications highlights that upstream fuel production pathways strongly influence overall performance, while use-phase contributions play a secondary role and mainly affect the final ranking when upstream emissions are comparable. Overall, the review shows that pathway selection is more influential than fuel identity itself, highlighting that effective decarbonization strategies should focus on pathway design and upstream fuel production rather than on fuel categories alone, and that renewable and bio-based pathways offer the greatest potential for achieving very low or near-zero life-cycle GHG emissions in internal combustion engine applications. Full article

The maritime sector accounts for approximately 3% of global greenhouse gas (GHG) emissions and faces binding decarbonization obligations under the International Maritime Organization’s (IMO) Net-Zero Framework and the FuelEU Maritime Regulation. Conventional marine fuels, including very low sulphur fuel oil (VLSFO) and liquefied natural gas (LNG), are insufficient to meet long-term regulatory intensity targets on a well-to-wake (WtW) lifecycle basis, creating an urgent need for credible fuel alternatives. This study investigates ethanol as a primary fuel for marine dual-fuel propulsion systems, assessed across four distinct production pathways, sugar beet, corn, sugarcane, and wheat straw, to determine its full decarbonization potential relative to VLSFO and LNG benchmarks. A simulation-based multi-dimensional evaluation framework is developed and applied, integrating dynamic operational simulation, energy analysis, environmental lifecycle modelling, and regulatory compliance assessment. The framework is calibrated against a high-resolution dataset from an active container ship, with scenario-specific engine data. While ethanol requires 39.1% more fuel mass than VLSFO due to its lower energy density, all four ethanol pathways deliver substantially superior WtW GHG reductions: from 50.2% (corn) to 76.9% (wheat straw), compared with 20.6% for LNG. All ethanol scenarios satisfy FuelEU compliance limits across the 2026–2045 horizon, with wheat straw ethanol achieving a GFI of 22.52 gCO₂e/MJ, compliant marginally with the 2040 IMO target. These findings demonstrate that bio-based ethanol, particularly from lignocellulosic feedstocks, is a technically viable and regulatorily superior alternative to LNG for maritime decarbonization, warranting accelerated research into production scale-up and bunkering infrastructure development. Full article

The Polarization and Directionality of the Earth’s Reflectances (POLDER)-3/GRASP (Generalized Retrieval of Aerosol and Surface Properties) aerosol products have been widely used in studies on radiative balance and climate change. However, the stability and consistency of the products have yet to be comprehensively evaluated, despite their critical importance for long-term studies. POLDER-3/GRASP products mainly consist of three variants: High-Precision (HP), Components, and Models. This study aims to evaluate the accuracy, stability, and consistency of these aerosol products at global and regional scales, and to provide usage recommendations. Compared with AERONET observations, the Components product shows the best performance for both aerosol optical depth (AOD) and Ångström Exponent (AE) retrievals, with Root Mean Square Error (RMSE) of 0.114 for AOD and 0.319 for AE. The Models AOD and HP AE also demonstrate relatively high validation accuracy, with RMSE of 0.138 for Models AOD and 0.366 for HP AE. Regionally, Components AOD and AE outperform those from the HP and Models products in 8 out of 10 regions. Stability evaluation shows that the stability metrics of the three AOD products range from 0.034 to 0.036 per decade, and none of them meet the Global Climate Observing System (GCOS) stability requirement (i.e., 0.02 per decade), which indicates that caution should be exercised when using POLDER-3/GRASP products for long-term analysis. In terms of consistency, Components AOD and Models AOD exhibit high agreement, while HP AOD is systematically higher than them. The AE retrieved by the three products shows considerable discrepancies, highlighting uncertainties in AE and spectral-AOD retrievals and pointing toward directions for future algorithmic improvements. In summary, considering global and regional accuracy, stability, and consistency, the Components AOD and AE products are generally recommended for use. For different regions, users can choose the appropriate product based on detailed validation and intercomparison results. Full article

The energy transition is widely regarded as one of the most significant challenges in achieving global climate goals, given that the energy sector is responsible for approximately 73% of greenhouse gas (GHG) emissions. Therefore, the integration of ESG criteria is emerging as a strategic lever for guiding companies, investors, and public decision-makers towards low-emission models. The present study employs a multi-case comparative approach, analyzing two utilities at differing stages of maturity: Ørsted, a global leader in the field of renewable energy transition, and Enel, a major European incumbent in the advanced stage of transformation. The methodology employed is founded upon the utilization of publicly available data and ESG indicators, encompassing the environmental, social and governance dimensions. The results underscore Ørsted’s position as a frontrunner in the field of climate leadership, as evidenced by their 91% reliance on renewable energy sources and an emission intensity of 60 gCO₂/kWh. In comparison, Enel’s figures stand at 49.4% and 237 gCO₂/kWh, respectively. The analysis further reveals a convergence trend across the social and governance pillars. Notably, Enel has demonstrated improvements in safety, inclusion, and leadership diversity. A ten-year scenario analysis suggests significant convergence for Enel, with an expected renewable generation share of 90% and a reduction in emissions to around 60 gCO₂/kWh. The present study makes a contribution to the extant literature by means of the proposal of a replicable, intensity-based ESG comparative framework that integrates normalized indicators with forward-looking scenario analysis. This enables a dynamic assessment of ESG convergence trajectories in the energy sector. Full article