Search Results (3,835)

This study examined whether acute exercise performed within individualized physiological intensity zones affects multidimensional soccer shooting performance. Twenty male collegiate soccer players completed a Yo-Yo Intermittent Recovery Test Level 1 with portable gas analysis to determine the ventilatory threshold (VT) and respiratory compensation point (RCP). Three individualized zones were defined: Low (<VT), Moderate (VT–RCP), and High (>RCP). In a randomized design, players completed three 3 min shuttle-running bouts, each followed immediately by the 356 Soccer Shooting Test. Ball velocity (BV), shooting accuracy (SA), and shooting quality (SQ) were analyzed using repeated-measures ANOVA. Exercise condition significantly affected SA (p = 0.013) and SQ (p = 0.007), but not BV (p = 0.216). Bonferroni-adjusted comparisons showed that SA and SQ were lower in High than in Low, whereas no pairwise BV comparison reached significance. A sensitivity analysis using all ten recorded attempts rather than the original best-seven scoring approach showed an overall condition effect for BV without a significant pairwise comparison, retained overall effects for SA and SQ, and showed that the Low–High contrast remained robust only for SQ. Baseline comparisons were not significant. These findings indicate condition-specific shooting responses, with the clearest evidence for lower SQ after High compared with Low, supportive evidence for lower SA, and no significant primary condition effect for BV. Full article

Injecting CO₂ into gas reservoirs is a crucial approach for enhancing natural gas recovery and achieving CO₂ geological storage, where the gas–gas diffusion behavior between CO₂ and CH₄ directly influences gas mixing efficiency. Direct observation of the spatiotemporal evolution of concentration fields during diffusion remains insufficient. In this study, a gas–gas diffusion experimental system capable of multi-time and multi-space stratified sampling within a high-temperature high-pressure PVT cell was established based on real reservoir fluid compositions. Non-equilibrium diffusion experiments were conducted under different pressures, different initial CO₂ mole fractions, and different diffusion times. A diffusion model was developed according to Fick’s second law. The results suggest that the gas column can be divided into a natural gas zone, a transition zone, and a CO₂ zone by the dimensionless concentration gradient threshold. At 5 MPa, the transition zone width expands rapidly within the first 4 h (dimensionless width increases from 0 to 0.6902), after which growth slows. Increasing pressure significantly inhibits diffusion, reducing transition zone width and prolonging equilibration time. Rising initial CO₂ concentration also suppresses diffusion mixing, particularly in the later stage. Component profile analysis confirms that, under high pressures and high CO₂ concentrations, the diffusion flux across the interface is weakened. Compared to CH₄, the diffusion equilibration time of CO₂ is shorter and more sensitive to pressure changes. The obtained diffusion coefficients (CH₄: 2.92 × 10⁻⁸ to 4.79 × 10⁻⁸ m²/s; CO₂: 3.91 × 10⁻⁸ to 6.08 × 10⁻⁸ m²/s) are on the order of 10⁻⁸ m²/s, consistent with bulk-phase PVT literature data, validating the reliability of the experimental method and inversion model. This study lays an experimental foundation for predicting multi-component gas mass transfer under conditions of CO₂-enhanced gas recovery and CO₂ geological storage. Full article

The transition to climate neutrality necessitates a profound transformation of mining systems. In this context, this study focuses on reviewing the role of circular economy models in transforming mining systems. Circular models propose reconfiguring systems into climate-neutral and more resource-efficient configurations. A synthesis of recent literature highlights several circular strategies frequently addressed throughout the mining life cycle. These include waste recovery, secondary resource recovery, water reuse, and the integration of renewable energy. The outcomes of circular approaches have the potential to reduce greenhouse gas emissions and resource consumption. They can also help improve the system’s efficiency through the creation of new economic value streams. Large scale implementation remains constrained because of economic, technological, and governance factors. In light of these findings, the paper recommends an integrated conceptual framework. It ties circular strategies to decarbonization pathways and sustainability outcomes. It does so because the circular economy is not merely a supporting approach but a necessary mechanism to enable the transition to climate-neutral and regenerative mining systems. Full article

Before launch, cryogenic propellant tanks experience a pre-pressurization stage during which their thermodynamic behavior is sensitive to operating conditions and external disturbances. For liquid hydrogen (LH2) storage tanks, small-amplitude oscillations may modify interfacial transport and phase change, thereby influencing pressure evolution and mass distribution. In this study, a computational fluid dynamics (CFD) model that accounts for gas–liquid interfacial phase change and environmental heat leakage is developed to investigate the thermodynamic response of an LH2 tank subjected to slight external oscillation during pre-pressurization. The effects of oscillation amplitude, inlet gas temperature, mass flow rate, and initial ullage gas fraction on temperature distribution, pressure development, and phase mass variation are analyzed. The results indicate that increasing the oscillation amplitude from 0.006 m to 0.014 m delays the pressurization time from 4.72 s to 5.04 s, while higher inlet temperatures (e.g., 330 K vs. 280 K) shorten the time to reach the target pressure but weaken interfacial condensation, resulting in a slower recovery of liquid hydrogen mass. Raising the inlet mass flow rate from 0.20 kg/s to 0.40 kg/s reduces the time to reach the preset pressure by approximately 56%, and larger initial ullage gas fractions (ullage height from 1 m to 6 m) significantly prolong the pressurization time and produce a wider high-temperature region. These quantitative results clarify the coupled oscillation-thermodynamic effects and can support optimization of LH2 tank operation during pre-pressurization. Full article

In response to the dual pressures of energy consumption and environmental pollution faced by the global shipping industry, this paper proposes an optimization method for the energy storage capacity of a ship’s hybrid energy system based on a two-layer optimization model, aiming to enhance the energy utilization efficiency and operational stability of the system. A DNN-IPSO optimization framework integrating deep neural networks (DNN) and the improved particle swarm optimization algorithm (IPSO) was constructed, and combined with robust control strategies, it optimized the energy storage capacity configuration problem under complex dynamic conditions. The results show that the proposed method exhibits superior performance in terms of energy utilization efficiency, system dynamic response, and stability. The energy utilization efficiency of the system has been increased to 91.3%, the bus voltage fluctuation has been reduced to 3.98%, the load tracking error has been decreased to 17.6 kW, and the average convergence iteration times have been reduced to 71 times. The 17.6 kW load tracking error accounts for only 1.76% of the rated propulsion power of the 1 MW-level experimental platform, which is approximately 38% lower than that of the GA-PSO method. The experimental results on the real ship show that after using the DNN-IPSO optimization, the unit voyage energy consumption has been reduced to 41.7 kWh/km, the propulsion power stability coefficient has been increased to 0.956, the system transient recovery time has been shortened to 3.2 s, and the power reserve margin has been increased to 18.4%. The proposed method can effectively enhance the energy management capability, dynamic response performance, and operational stability of the ship’s hybrid energy system in the actual operating environment, providing reliable technical support for the engineering application of the integrated energy system of ships. Full article

Diesel is a major soil contaminant that poses significant environmental risks, making its removal essential. This study investigates the synergistic application of thermal desorption (TD) and thermal plasma for the remediation of diesel-contaminated soil, while simultaneously converting desorbed contaminants into valuable gaseous products. Artificially contaminated soil (25 g/kg) was treated by TD at 250–300 °C and the resulting off-gas and volatilized diesel were subsequently processed in a thermal plasma system. Soil samples were characterized using CHNS, EDX, FTIR, and TGA/DTG analyses, while gas composition was determined using a gas analyzer. The results demonstrate that TD achieved diesel removal efficiencies of up to 86% at 300 °C and 65% at 250 °C. TD off-gas and volatilized diesel were predominantly converted into synthesis gas (H₂ + CO) in a thermal plasma environment, with H₂ and CO concentrations reaching up to 15.49 vol% and 7.61 vol%, respectively, depending on the plasma-forming gas, carrier gas flow rate, and remediation temperature. Thermal treatment of diesel-contaminated soil significantly altered key physicochemical properties, including reduced organic matter content, increased soil compaction, and temperature-dependent shifts in pH and nitrogen speciation (decreased NO₃⁻-N and increased NH₄⁺-N). These changes were accompanied by enhanced phosphorus availability, indicating substantial thermally induced transformation of soil nutrients. Phytotoxicity assessment using Lepidium sativum in a soil leachate-based bioassay indicated that higher treatment temperature (300 °C) increased toxicity and inhibited plant growth, whereas treatment at 250 °C resulted in lower phytotoxicity. These findings highlight the adaptability of the proposed combination of methods enabling effective soil remediation while supporting energy recovery. Full article

Recyclers worldwide face a common bottleneck: incoming mixed plastic bales are chemically opaque, yet the choice between mechanical recycling, chemical recycling, and energy recovery hinges on contaminant levels that cannot be judged by visual inspection alone. This study develops and validates a tiered analytical decision-support framework that translates standard laboratory measurements into explicit, actionable go/no-go routing criteria for any mixed polyolefin waste stream. The framework is organized into three successive analytical tiers of increasing specificity: Tier 1 uses FTIR and DSC for rapid polymer identification and thermal subclass confirmation; Tier 2 applies TGA/DTG for thermal stability assessment and filler quantification; and Tier 3 deploys ICP-OES, WD-XRF, CIC, and TG–MS for targeted heavy metal, halogen, and evolved gas profiling, triggered only when Tier 1/2 flags are raised. This staged logic minimizes unnecessary testing while ensuring that contaminant-relevant information is captured where it matters. The framework is demonstrated on nine blind mixed plastic waste streams (P1–P9) supplied by an industrial recycling facility without prior disclosure of polymer identity, filler content, or additive history—conditions that replicate the uncertainty encountered at any sorting plant globally. Application of the tiered protocol identified dominant polymers (HDPE, LDPE, PP), quantified inorganic fillers (CaCO₃ up to ~38 wt%), and detected hazardous contaminants, including chlorine (up to ~1900 ppm), lead, chromium, and titanium, enabling each stream to be assigned to a specific recycling route with defined contaminant thresholds. Because the method relies exclusively on commercially available, vendor-independent instrumentation and follows a reproducible, rule-based decision logic, it is directly transferable to recycling facilities in any geographic context without site-specific calibration. The proposed framework thus provides a practical, scalable decision-support tool for feedstock-level quality control under emerging regulations such as the UNEP Global Plastics Treaty. Full article

Background: Fiberoptic bronchoscopy (FOB) is a procedure routinely performed in clinical practice for both diagnostic and therapeutic purposes. FOB frequently impairs respiratory function, which may exacerbate respiratory failure. Currently, conventional oxygen therapy (COT) is the most commonly used form of respiratory support; however, non-invasive ventilation (NIV) and high-flow nasal cannula (HFNC) are being used increasingly. The optimal settings and indications for NIV and HFNC in patients with respiratory acidosis undergoing FOB have not yet been determined. Methods: This is a prospective, multicenter, randomized controlled trial including two parallel study populations defined by the indication for bronchoscopy and the type of respiratory acidosis. Therapeutic FOB (Study 1): Patients with decompensated type 2 respiratory failure (pH < 7.35 and PaCO₂ > 45 mmHg) will be randomized to receive one of four methods of respiratory support during bronchoscopy: COT, NIV, HFNC, or invasive mechanical ventilation (IMV) (n = 315). Diagnostic FOB (Study 2): Patients with chronic respiratory acidosis (pH ≥ 7.35, PaCO₂ > 45 mmHg, and/or HCO₃⁻ > 27 mmol/L) will be randomized to receive COT, NIV, or HFNC during bronchoscopy (n = 210). Before FOB, patients in both groups will undergo arterial blood gas (ABG) analysis. During FOB, vital signs will be continuously monitored, including SpO₂, FiO₂, TcCO₂, ECG, and heart rate. After FOB, ABG analysis will be repeated, and study endpoints and complications, if any, will be recorded. The planned study period is from April 2026 to April 2029. Results: Based on the study results, we aim to evaluate the effectiveness and safety of different respiratory support strategies during flexible bronchoscopy, with the primary objective of comparing the rate of treatment failure among COT, HFNC, NIV, and IMV. Treatment failure is defined as the need for endotracheal intubation, premature termination of the procedure, or escalation of respiratory support. Additionally, we aim to identify the optimal NIV and HFNC settings, as well as complication rates in both study groups. Conclusions: The results of this study will help define the role of optimal respiratory support in patients with respiratory acidosis undergoing FOB, potentially leading to a shorter time from admission to diagnosis, better tolerance of the procedure, and faster recovery afterward. Full article

The geographic and economic contexts play a major role in decision-making when it comes to municipal solid waste management. In the present study, simulations are carried out using the Waste and Resource Assessment Tool for the Environment (WRATE) software academic version 3.0.1, based on the Ecoinvent database (version 2) to assess the greenhouse gas emissions released by 1 ton of municipal solid waste with a typical composition characterizing upper middle-income countries, with an organic fraction of approximately 50% by weight. The variation over time (2000 to 2022) with no intended transformation in the management strategy is first analyzed, then several transformations are applied by varying the waste management routes (open dumping, landfilling, recycling and composting) as well as the energy recovery integration. The results are then discussed based on the waste categories and the performed operations (landfilling, recycling, transportation, treatment and recovery). The results revealed that the most promising scenario includes limited open dumping that does not exceed 10%, landfilling with at least 20% energy recovery, and major fractions addressed to composting and recycling. Overall, this scenario returns a negative carbon footprint with a value of approximately−0.35 tons of CO₂-Eq/ton of MSW. Results are mostly applicable to countries with similar waste composition and infrastructure levels; preconditions include source segregation, compost markets, and landfill gas infrastructure. Full article

Electrocatalytic CO₂ reduction reaction (CO₂RR) to ethylene (C₂H₄) has emerged as a promising approach for converting CO₂ into valuable chemicals while utilizing renewable electricity. To facilitate the commercialization of this technology, a process-level techno-economic assessment (TEA) is constructed for a plant producing 100 tons/day of C₂H₄ from coal-power flue gas CO₂ using a membrane electrode assembly (MEA) electrolyzer and downstream gas separations. The model integrates (i) flue gas CO₂ capture by chemical absorption, (ii) CO₂RR to C₂H₄ with H₂ as the only co-product, and (iii) cathode off-gas separation by pressure swing adsorption (PSA) plus anode off-gas CO₂ recovery and recycle. A Cu₁₀–Sn catalyst measured in an H-cell is projected to MEA operation by scaling current density by 10×, yielding a “Case Study in This Article” scenario of j = 246 mA·cm⁻² and FE(C₂H₄) = 48.74%. Under this scenario, the total cost is 592.61 thousand USD/day (5926 USD/ton), dominated by electricity (39.8%). Scenario analysis shows that the total cost can decrease to 76,755.0 USD/day (767.6 USD/ton) under a future-outlook case with improved electrolyzer performance and low-cost power, enabling a net profit of 19,945.0 USD/day at an ethylene selling price of 967 USD/ton. Sensitivity analysis identifies FE(C₂H₄), full-cell voltage, and electricity price as the most influential variables. The results translate laboratory catalyst metrics into industrial cost drivers and clarify quantitative performance targets for commercialization. Full article

Heat pump technology can efficiently recover waste heat from oil and gas gathering, processing, and transportation. However, the energy transfer mechanism of high-speed rotating internal flow in the scroll compressor remains unclear under unbalanced load conditions, leading to low equipment energy efficiency and high operation and maintenance costs. This study adopted dynamic grid technology, finite element analysis and one-way thermal–fluid–solid coupling method to quantitatively study the flow field characteristics and mechanical response of four characteristic phases. The results showed that the internal pressure and temperature fields of the compressor presented a non-uniform distribution. The deformation of the scroll wraps was mainly concentrated in the compression chamber, and the maximum stress was concentrated at the wraps’ root. Further analysis revealed that temperature loading played a dominant role in the structural responses. At a spindle rotation angle of 0°, under temperature loading alone, the maximum deformation and maximum stress were 28.605 μm and 521.81 MPa, respectively, while the corresponding values under pressure loading alone were small. In addition, the deformation and stress under coupled loading were not a linear superposition of the individual loading effects, with a deformation deviation of 0.938 μm and a stress deviation of 7.18 MPa at a spindle rotation angle of 0°. In this study, a numerical model of the scroll compressor was established and experimentally verified, which provided a theoretical basis for optimizing scroll profile design, suppressing wrap tip wear and improving the energy efficiency of heat pump systems. Full article

Kawasaki disease (KD) represents the foremost cause of acquired pediatric heart disease, with coronary artery injury being the principal factor contributing to adverse prognoses. A significant clinical challenge is that 20–30% of patients demonstrate resistance to intravenous immunoglobulin (IVIG), which markedly elevates the risk of coronary artery lesions and long-term cardiovascular sequelae. Consequently, there is an urgent need to investigate novel pathogenic mechanisms beyond the conventional cytokine storm theory and to identify effective therapeutic targets. This review systematically summarizes the key role of the autophagy–inflammation axis in KD vasculopathy. Current evidence indicates that defective mitophagy and lysosomal dysfunction induce mitochondrial DNA release, resulting in overactivation of the NLRP3 inflammasome and cGAS-STING pathways, which amplify inflammatory responses and aggravate endothelial damage. The regulation of this axis is dynamic during both the acute and recovery phases and is influenced by metabolic reprogramming and epigenetic modifications, which may partially explain the lack of response to IVIG. Pharmacological agents, such as rapamycin and metformin, as well as natural compounds, such as resveratrol and urolithin A, have demonstrated beneficial anti-inflammatory effects in preclinical studies. Targeting the autophagy–inflammation axis represents a significant research direction with the potential to evolve into a promising therapeutic strategy. Mechanistically, restoring the balance of the autophagy–inflammation axis holds promise for mitigating coronary complications and improving long-term cardiovascular outcomes in children with KD; however, this prospect requires validation through prospective clinical studies. Full article

As a low-carbon alternative, methane pyrolysis offers a viable approach to overcoming the emission challenges associated with traditional hydrogen generation. However, catalyst deactivation is one of the key challenges, mainly caused by high-temperature sintering and coke deposition that block active sites. This study investigates the application of non-thermal plasma (NTP) treatment for the regeneration of coked catalysts through in situ carbon removal and performance recovery. Carbon removal by NTP is proposed as a cleaner alternative to conventional regeneration methods. The influence of plasma treatment was evaluated under different plasma treatment configurations, including the use of an auxiliary magnet to direct plasma flux toward the targeted region, and variations in gas composition (H₂/Ar and H₂/O₂). The plasma-treated catalyst was analyzed by SEM, EDS, XPS, and XRD techniques. Additionally, samples were evaluated for hydrogen production via methane pyrolysis. The results demonstrated measurable surface carbon removal, reaching approximately 38%. However, methane pyrolysis experiments revealed that this level of surface carbon removal was insufficient to achieve substantial catalytic activity recovery, indicating the need for further optimization. Full article

To investigate the carbon footprint of bamboo-based activated carbon from different manufacturing pathways, this research evaluated cradle-to-gate manufacturing emissions under a unified system boundary and allocation baseline based on primary data from a 10,000 t/year continuous industrial production line. An LCA model was constructed and verified using an allocation ratio interval scanning method. Results showed that carbon footprints of granular, powdered, and extruded activated carbons were 184.76 kg CO₂ e/t kg CO₂ e/t, 236.75 kg CO₂ e/t, and 293.36 kg CO₂ e/t. Although these products shared identical carbonization and steam activation units, the carbon footprints from milling, molding, and binder inputs accounted for 25.01%, 41.48%, and 52.77% of the total emissions. Internal thermal energy recovery via by-product gas recycling decreased emissions by 81.7%, 77.7%, and 73.8%, respectively. Compared with traditional coal-based alternatives, bamboo-based products achieved a reduction in emissions of about 95%. This study provides scientific guidance for the low-carbon production process of bamboo-based activated carbon and demonstrates the potential of biomass substitution for climate change mitigation. Full article

Given the large natural gas (NG) reserves of the Intermountain West (I-WEST) region in the USA, it can emerge as a leader in hydrogen (H₂) production. Currently, H₂ production via steam methane reforming (SMR) of NG releases carbon dioxide (CO₂) and the natural gas infrastructure has fugitive NG and H₂ losses during production, conversion and transportation. Integrated carbon capture and sequestration (CCS) is a promising approach for producing hydrogen and CO₂ from the SMR process for industrial uses including power, chemicals and fuels. However, the NG losses and regional water availability can be limiting factors for H₂ production. H₂ production assessments are often made at the global scale and neglect regional factors such as abundant gas and limited water in the I-WEST. We demonstrate that a regional SMR process unit sitting near NG wells offers opportunities to significantly reduce fugitive NG losses. We show that regional H₂ production by SMR has a lower emissions profile than widespread natural gas combustion in the I-WEST and reduces the H₂ production cost as well. Replacing the I-WEST transportation sector with H₂ fuel cell vehicles and using 100% H₂-powered electricity can provide substantial reductions in water consumption and fuel costs. This is better than blending H₂ with NG which is more expensive. The captured CO₂ can be effectively used for enhanced oil recovery in I-WEST. Finally, the potential of utilizing produced, brackish and treated impaired water sources is assessed to meet the water needs for H₂ production in the I-WEST. Full article