Deep saline aquifers represents one of the most geologically promising solutions for large-scale carbon dioxide (CO2) sequestration, boasting a global storage potential of up to 10,000 Gt of CO2, which far exceeds other subsurface options. This comprehensive review systematically examines recent advancements in aquifers-based CO2 sequestration through experimental studies, simulations, pore-scale analyses, and field applications. Major trapping mechanisms, including structural, residual, solubility, and mineral trapping, are critically evaluated together with key factors affecting storage efficiency, injectivity, and long-term containment security. This study highlights the potential of CO2 foams for enhancing storage efficiency through improved mobility control and sweep efficiency within saline aquifers as overlooked by previous reviews. Additionally, it provides a detailed pore-scale analysis of CO2-brine-rock interactions, providing new insights into multiphase flow dynamics and trapping mechanisms at the microscopic level, which are crucial for accurate reservoir-scale predictions. Moreover, it explore the emerging role of microbial processes in CO2 sequestration, including their impact on mineralization and the security of long-term storage through biogeochemical interactions. In addition, the mechanical integrity of saline aquifers during CO2 injections was discussed in details as not discussed in previous reviews. A dedicated discussion of salt precipitation is presented, including deposition stages, influencing factors such as brine chemistry and injection conditions, and mitigation strategies for maintaining injectivity. The review also identifies key challenges and research gaps for futures researches related to long-term storage prediction, coupled process modeling, and economic feasibility. By integrating insights from pore-scale mechanisms to field-scale applications, this work provides a multidisciplinary framework for advancing aquifers-based CO2 sequestration as a safe and scalable climate mitigation technology.
Microalgae biorefineries offer a route to sustainable fuels, yet most techno-economic analyses (TEAs) and life cycle assessments (LCAs) address narrow product portfolios within cradle-to-gate boundaries. This study presents the first cradle-to-grave TEA and LCA of a commercial-scale, continuous-mode, wastewater-fed photobioreactor (PBR) biorefinery producing 1,000,000 gal/yr biodiesel while treating ≈8.9 million m3/yr of tertiary wastewater through five-tier cascading valorization of Chlorella vulgaris biomass. Three scenarios were modeled in SuperPro Designer and SimaPro: a biodiesel-plus-fertilizer baseline (S1); added pigment extraction and enzymatic protein hydrolysis (S2); and a full cascade adding two-stage biohythane recovery via dark fermentation and co-digestion (S3). Cascading valorization raised co-product revenue by ∼600%, cutting the minimum fuel selling price (MFSP) from $198.22 to $158.06/gal (−20.3%); S3 yielded a statistically indistinguishable $159.99/gal, and Monte Carlo simulation confirmed robust separation of S2/S3 from S1. The LCA (ReCiPe Midpoint) showed that PBR cultivation electricity (345 kWh/gal; 90.4% of process-electricity demand) dominated 17 of 18 impact categories, making grid decarbonization the primary improvement lever. Absolute impacts are specific to the fossil-dominated GCC grid, whereas the cultivation-electricity hotspot and the relative effects of cascading valorization generalize across electricity mixes. Valorization deepened land-use credits 3.2-fold via soy-protein displacement but shifted burdens toward water consumption and terrestrial ecotoxicity. Pigment price and electricity cost dominated the sensitivity analysis; under moderate co-product pricing ($7/kg protein, $300/kg pigments), MFSP fell to $16.92–18.73/gal (∼89% reduction). Economic allocation per ISO 14044 reduced the biodiesel-attributed GWP to ≈13.5–13.8 kg CO2-eq/gal, approaching fossil-diesel parity as co-products absorb most of the burden.
This paper presents a five-level switched-capacitor multilevel inverter (SCMLI) with dual boosting and common-ground (CG) capability for standalone and grid-connected applications. The proposed converter employs two switched capacitors (SCs), six switches, and two diodes while charging both capacitors only to the input voltage, resulting in reduced capacitor rating and cost. Unlike existing five-level converters, the proposed topology can continue operating as a three-level inverter under the failure of either switched capacitor resulting in improved inverter reliability. To mitigate the large charging-current spikes commonly encountered in SCMLIs, a quasi-soft charging technique using a small charging inductor is introduced, and a practical design methodology is presented. The charging inductor significantly reduces peak capacitor charging current, lowers current stress on semiconductor devices, and improves converter efficiency. The proposed converter is further analyzed in terms of leakage-current mitigation, voltage and current stresses, power loss, efficiency, scalability, and cost, and is quantitatively compared with recently reported common-ground five-level inverters. Experimental results obtained from a 1-kW prototype validate the converter under different operating conditions, including load and modulation variations, while hardware-in-the-loop results demonstrate successful grid-connected operation with effective active and reactive power control.
Graphitic carbon nitride (g-C3N4) is an emerging nanomaterial with unique features such as photocatalyst, biocompatibility, and tunable surface chemistry, placing g-C₃N₄ as a versatile platform for innovative biomedical applications. This review explores the properties, synthesis, biomedical applications, challenges, and future perspectives of g-C₃N₄. An electronic search of PubMed and Elsevier’s Scopus was undertaken, with no limits to the year of publication, and only English-language literature was included. One of the notable applications is as a drug delivery system due to its large surface area, functional tunability, and controlled release mechanisms. Recently, g-C3N4 has also emerged as a promising agent for cancer treatment, particularly in photodynamic and photothermal therapies. Another widely explored application is its role in regenerative medicine, including wound healing, where its biocompatibility and ability to enhance cellular interactions are advantageous. Additionally, g-C3N4 demonstrates strong potential in biosensing and bioimaging, leveraging its fluorescence properties for diagnostic and monitoring applications. While direct studies in dentistry are limited, these biomedical advancements suggest a potential for future dental applications, particularly in antimicrobial coatings, drug-loaded restorative materials, and guided tissue regeneration. Future research should focus on optimizing g-C3N4-based materials for targeted clinical applications, particularly within dentistry.
This study uses the Stimulus-Organism-Response (S-O-R) framework and appraisal theory to examine how environmental sustainability initiatives (ESIs) function as external stimuli that trigger emotional reactions (brand happiness and brand love) as organism states. These emotional responses, in turn, lead to brand evangelism as the response. It also explores how time orientation (future, present, and past) moderates the emotional impact of ESIs. Survey data from 501 hotel customers were analyzed using structural equation modeling. Results show that ESIs significantly enhance both brand happiness and love, with brand love more strongly driving brand evangelism due to its deeper, more enduring passion and commitment compared to the momentary nature of happiness. Further, moderation analysis revealed that future orientation strengthened the effects of ESIs on both happiness and love, suggesting that forward-focused consumers more readily appraise ESIs as personally meaningful. In contrast, present orientation had a significant negative impact on these effects, indicating active resistance of future-oriented brand actions. Past orientation had no significant effect, reflecting appraisal detachment (i.e. neither reject nor embrace ESIs) rather than value conflict. The findings suggest that hotels should adopt a dual-pathway ESI strategy that engages both immediate experiential pleasure and deeper emotional connections and tailor messaging to customers' time orientations to maximize emotional impact and advocacy.
