Search Results (121)

Environmental fines compel corporations to strengthen compliance, adopt sustainable practices, and integrate eco-innovation. This enhances legitimacy, reduces risks, and supports long-term sustainable performance across industries. Despite this importance, its effect on corporate sustainability performance (CSP) and the moderating roles of corporate governance quality, firm size, and institutional ownership remain underexplored, creating significant knowledge gaps. This study applied stakeholder and institutional theory to address these gaps, using data from 187 non-financial firms listed on the Frankfurt Stock Exchange between 2006 and 2024, obtained from Thomson Reuters Eikon DataStream. Three advanced estimation models—augmented mean group (AMG), common correlated effects mean group (CCEMG), and generalized method of moments (GMM)—were employed. Findings indicate that environmental fines have a positive and significant effect on CSP. Moreover, the moderating effects of governance quality, firm size, and institutional ownership also positively and significantly influence CSP. Strong governance enables firms to transform fines into strategic opportunities, driving sustainability investments, improving risk management, and fostering accountability that aligns operations with regulatory and stakeholder expectations. Full article

The gas equation of state (EOS) serves as a critical tool for analyzing the thermal effects within the hydrogen storage tank during refueling processes. It quantifies the dynamic relationships among pressure, temperature and volume, playing a vital role in numerical simulations of hydrogen refueling, the development of refueling protocols, and ensuring refueling safety. This study first establishes a lumped-parameter thermodynamic model for the hydrogen refueling process, which combines a zero-dimensional gas model with a one-dimensional tank wall model (0D1D). The model’s accuracy was validated against experimental data and will be used in combination with different EOSs to simulate hydrogen temperature and pressure. Subsequently, parameter values are derived for the van der Waals EOS and its modified forms—Redlich–Kwong, Soave, and Peng–Robinson. The accuracy of the modified forms is evaluated using the Joule–Thomson inversion curve. A polynomial EOS is formulated, and its parameters are numerically determined. Finally, the hydrogen temperatures and pressures calculated using the van der Waals EOS, Redlich–Kwong EOS, polynomial EOS, and the National Institute of Standards and Technology (NIST) database are compared. Within the initial and boundary conditions set in this study, the results indicate that among the modified forms for van der Waals EOS, the Redlich–Kwong EOS exhibits higher accuracy than the Soave and Peng–Robinson EOSs. Using the NIST-calculated hydrogen pressure as a benchmark, the relative error is 0.30% for the polynomial EOS, 1.83% for the Redlich–Kwong EOS, and 17.90% for the van der Waals EOS. Thus, the polynomial EOS exhibits higher accuracy, followed by the Redlich–Kwong EOS, while the van der Waals EOS demonstrates lower accuracy. This research provides a theoretical basis for selecting an appropriate EOS in numerical simulations of hydrogen refueling processes. Full article

Mesoporous silica materials with well-organized architectures were synthesized using a series of Pluronic PE-type triblock copolymers (PE6800, PE9200, PE9400, PE10500) as structure-directing agents under acidic conditions. The study aimed to elucidate the impact of synthesis parameters—copolymer type, presence of a swelling agent, 1,3,5-trimethylbenzene, aging temperature, and silica precursor—on the structural, textural, and functional properties of the resulting mesocellular foam materials. Characterization by Nitrogen Adsorption/Desorption, Transmission Electron Microscopy, X-ray Diffraction, and Small-angle X-ray Scattering revealed that structural ordering and pore morphology are significantly influenced by the EO/PO ratio of the copolymers and the use of the expander. Materials synthesized with PE9400 and PE10500 in the presence of a swelling agent exhibited highly uniform bottle-shaped mesopores with increased surface area and pore volume. Thermal behavior studied via Differential Scanning Calorimetry indicated a correlation between pore size and melting point depression of confined water, consistent with the Gibbs–Thomson effect. Adsorption capacity and kinetics for methylene blue varied significantly with pore structure, with materials possessing narrow mesopores showing superior dye uptake, and materials with larger mesopores and open-pore architecture exhibiting faster adsorption rates. This work demonstrates the tunability of mesoporous silica structure through precise control of synthesis conditions and highlights its potential in applications involving adsorption and phase phenomena in confined pore systems. Full article

Many companies engage in earnings manipulation that obscures their actual financial condition and sustainability efforts, undermining the credibility of financial reports and eroding stakeholder trust. To address these concerns, the United Kingdom has strictly adhered to International Financial Reporting Standards (IFRS), enhancing financial transparency and reducing the risk of manipulation. This study applies agency theory to examine the effects of earnings management and IFRS adoption on corporate sustainability performance, while also assessing the moderating roles of institutional ownership and board independence. Data were drawn from 248 companies listed on the London Stock Exchange between 2002 and 2024, using purposive sampling and sourced from Thomson Reuters Eikon DataStream. Advanced estimation techniques, specifically the Augmented Mean Group (AMG) and fixed effects models with Driscoll-Kraay standard errors, were employed to address cross-sectional dependence and slope heterogeneity. The results indicate that earnings management, as measured by discretionary accruals, has a significant negative impact on sustainability performance. In contrast, the adoption of IFRS has a positive and significant influence on sustainability outcomes. Additionally, institutional ownership and board independence significantly moderate the adverse effects of earnings management, leading to improved sustainability performance. The findings suggest that managers should enhance the clarity and accountability of financial reporting by implementing robust internal systems aligned with IFRS, conducting regular compliance audits, and training finance staff on current disclosure standards. Full article

Banks in the United States face persistent challenges from non-performing loans (NPLs), despite conducting thorough client evaluations before issuing loans. To mitigate the impact of NPLs and support both local and global growth, banks must adopt effective risk management strategies. This study investigates the effect of NPLs on bank growth and the moderating of bank size and Capital Adequacy Ratio (CAR) through the lens of the Resource-Based View (RBV) theory. A sample of 253 banks listed on the New York Stock Exchange from 2006 to 2023 was selected using specific inclusion criteria from the Thomson Reuters Eikon DataStream. To address cross-sectional dependence and endogeneity, advanced estimation techniques—Feasible Generalized Least Squares (FGLS), Driscoll and Kraay standard errors, and the Generalized Method of Moments (GMM)—were employed. The results show that NPLs have a significant negative impact on banks’ asset and income growth. Furthermore, bank size and capital adequacy ratio (CAR) negatively and significantly moderate this relationship. These findings underscore the need for banks to enhance credit risk management by strengthening loan approval processes and leveraging advanced analytics to assess borrower risk more accurately. Full article

With the rapid development of hydrogen fuel cell vehicles, the research on the throttling effect of high-pressure hydrogen is crucial to the safety of hydrogen circulation systems for fuel cells. This paper studies the Joule-Thomson coefficients (${\mathrm{\mu }}_{\mathrm{J}\mathrm{T}}$) of ten gas state equations. The four equations, Van Der Waals (VDW), Redlich-Kwong (RK), Soave-Redlich-Kwong (SRK), and Beattie Bridgeman (BB), were selected for calculation. These were compared with the database of the National Institute of Standards and Technology (NIST), aiming to determine the optimal state equation under different temperature and pressure conditions. The empirical formula of the ${\mathrm{\mu }}_{\mathrm{J}\mathrm{T}}$ pressure and temperature was compounded, and the temperature rise effect was further calculated using the empirical formula of compounding. The results show that the calculated value of ${\mathrm{\mu }}_{\mathrm{J}\mathrm{T}}$ by using the VDW equation in the low-pressure range (0–2 MPa) is closer to the value in the NIST database with an error less than 0.056 $\mathrm{K}·{\mathrm{M}\mathrm{P}\mathrm{a}}^{-1}$. The tendency of ${\mathrm{\mu }}_{\mathrm{J}\mathrm{T}}$ described by the RK equation corresponds to the NIST database; meanwhile, the maximum error in the SRK equation is 0.143916 $\mathrm{K}·{\mathrm{M}\mathrm{P}\mathrm{a}}^{-1}$. The BB equation is more applicable within the pressure range of 20 to 50 MPa with a maximum error of 0.042853 $\mathrm{K}·{\mathrm{M}\mathrm{P}\mathrm{a}}^{-1}$. The fitting error of the empirical formula is within 9.52%, and the relative error of the calculated temperature rise is less than 4%. This research might provide several technical ideas for the study of the throttling effect of hydrogen refueling stations and the hydrogen circulation system of on-board hydrogen fuel cells. 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

The southern margin block of the Xinjiang Oilfield represents a typical ultra-high-pressure condensate gas field. Existing surface throttling practices rely heavily on empirical experience, with the underlying throttling mechanisms remaining unclear and lacking systematic theoretical support. In this study, the TW1 Well is selected as the research subject. Based on the principle of equal total enthalpy before and after throttling—and with particular attention to the effects of condensate gas heavy components and water on enthalpy calculations—a mathematical model for throttling-induced temperature drop, tailored to ultra-high-pressure condensate gas, is developed. The model enables a systematic analysis of temperature variations throughout the throttling process. Results indicate that the pre-throttle temperature is the primary factor controlling the magnitude of temperature change, and that post-throttle temperature rise may occur due to the Joule–Thomson coefficient becoming negative under ultra-high-pressure conditions. By integrating hydrate-formation prediction with differential pressure calculations across the throttling valve, a rational production scheme is proposed. This study provides a theoretical basis for understanding the mechanisms of ultra-high-pressure condensate gas well throttling and delivers critical technical support for the scientific design and optimization of surface throttling operations. Full article

Bank operations are contingent upon investor confidence, particularly during periods of economic distress. If investor confidence drops, a bank faces difficulties obtaining money, higher borrowing costs, and lower stock values. Non-performing loans (NPLs) potentially jeopardize a bank’s long-term viability and short-term profitability, and investors are naturally wary of institutions that pose a high credit risk. The purpose of the study was to explore how non-performing loans influence investor confidence in banks. A purposive sampling technique was used to identify 253 New York Stock Exchange banks in the Thomson Reuters Eikon DataStream that satisfied all the inclusion and exclusion selection criteria. The Common Correlated Effects Mean Group (CCEMG) and Generalized Method of Moments (GMM) models were used to analyze the data, providing insight into the relationship between the variables. The study discovered that NPLs had a negative and significant influence on price–earnings (P/E) and price-to-book value (P/B) ratios. Furthermore, the bank’s age was found to have a positive and significant relationship with the P/E and P/B ratio. The moderating relationship between NPLs and bank age was found to have a negative and significant influence on price–earnings (P/E) and price-to-book value (P/B) ratios. The findings underscore the importance of asset quality and institutional reputation in influencing market perceptions. Bank managers should focus on managing non-performing loans effectively and leveraging institutional credibility to sustain investor confidence, particularly during financial distress. Full article

Extensive numerical simulations were performed in MATLAB R2020b based on the classical nonlinear Thomson scattering theory and single-electron model, to systematically examine the influence of initial phase in tightly focused linearly polarized laser pulses on the radiation characteristics of multi-energy-level electrons. Through our research, we have found that phase variation from 0 to 2π induces an angular bifurcation of peak radiation intensity, generating polarization-aligned symmetric lobes with azimuthal invariance. Furthermore, the bimodal polar angle decreases with the increase of the initial energy. This phase-controllable bimodal distribution provides a new solution for far-field beam shaping. Significantly, high-harmonic intensity demonstrates π-periodic phase-dependent modulation. Meanwhile, the time-domain pulse width also exhibits 2π-cycle modulation, which is synchronized with the laser electric field period. Notably, electron energy increase enhances laser pulse peak intensity while compressing its duration. The above findings demonstrate that the precise control of the driving laser’s initial phase enables effective manipulation of the radiation’s spatial characteristics. Full article

The purpose of this paper is to forecast the sovereign credit risk for Egypt, Morocco, and Saudi Arabia during political crises. Our approach uses machine learning models (Linear Regression, Ridge Regression, Lasso Regression, XGBoost, and Kernel Ridge) and deep learning models (RNN, LSTM, BiLSTM, and GRU) to predict CDS-based implied default probabilities. We compare the predictive accuracy of the tested models with the results showing that Linear Regression outperforms all other techniques, while deep learning architectures, such as RNN and GRU, demonstrate a competitive performance. To validate the sovereign credit risk prediction, we use the forecasted implied default probability from the Linear Regression model to determine the corresponding forecasted implied rating according to the Thomson Reuters StarMine Sovereign Risk model. The results reveal significant differences in the perceived creditworthiness of Egypt, Morocco, and Saudi Arabia, reflecting each country’s economic fundamentals and their ability to manage global shocks, particularly those related to the Russo-Ukrainian war. Specifically, Egypt is perceived as the most vulnerable, Morocco occupies an intermediate position, and Saudi Arabia is seen as having a low credit risk. This study provides valuable managerial insights by enhancing tools for the sovereign credit risk analysis, offering reliable decision-making in volatile global markets. The alignment between forecasted ratings and default probabilities underscores the practical relevance of the results, guiding stakeholders in effectively managing credit risks amidst economic uncertainty. Full article

The Second Law of Thermodynamics states that entropy S increases in a spontaneous process in an ideal isothermal and isolated system. Real systems are influenced by external forces and fields, including the temperature field. In this case, only entropy is not enough, and we suggest using a new function, $L_s$, which is analogous to the Lagrangian in classical mechanics. It includes total potential energy but instead of mechanical kinetic energy, $L_s$ includes the product ST, and the system always evolves towards increasing this modified Lagrangian. It reaches an equilibrium when total potential force is balanced by both entropic and thermal forces. All forces have the same units, Newton/mol, and may be added or subtracted. For condensed systems with friction forces, it is a molecular transport velocity, and not acceleration, which is proportional to the acting force. Our approach has several advantages compared to Onsager’s non-equilibrium thermodynamics with its thermodynamic forces, which may have different units, including 1/T for energy transport. For isolated systems, the description is reduced to Second Law and Clausius inequality. It easily explains diffusion, Dufour effect, and Soret thermodiffusion. The combination of electric, thermal, and entropic forces explains thermoelectric phenomena, including Peltier–Seebeck and Thomson (Lord Kelvin) effects. Gravitational and entropic forces together inside a black hole may lead to a steady state or the black hole evaporation. They are also involved in and influenced by solar atmospheric processes. Full article

Abandoned production and monitoring wells in depleted oil and gas fields can readily serve as primary leakage pathways for stored CO₂. The temperature, pressure conditions around the wellbore bottom, and CO₂ concentration influence the phase behavior of CO₂ during leakage. This study establishes a 3D wellbore–reservoir coupled model using CO₂ injection data from 1 December 2009, in the DAS area, eastern Cranfield oilfield, Mississippi, USA, to analyze the dynamic evolution of CO₂ leakage along wellbores. Simulations are conducted using the collaboration of ECO2M and ECO2N v2.0 modules. The study examines leakage regimes under varying distances from the injection well and different reservoir temperatures. The results indicate that CO₂ phase changes occur primarily in wells near the injection point or under high-pressure and high CO₂ saturation conditions, usually with a short leakage period due to ice formation at the wellhead. In areas with low CO₂ saturation, prolonged leakage periods lead to significant pressure drops at the bottom, as well as the temperature as a result of the Joule–Thomson effect. Lower reservoir temperatures facilitate smoother and more gradual leakage. These findings provide a theoretical foundation for ensuring the safe implementation of CCUS projects and offer insights into the mechanical explanation of CO₂ geyser phenomena. Full article

Mixing and matching N₂-fixing leguminous species is a crucial strategy to enhance quality and efficiency in sustainable forestry. Tree leaves and rhizosphere are primary sites for matter and energy exchange, functioning as key assimilation organs that forests provide for ecological services. The introduction of functional species alters soil properties, which, in turn, directly or indirectly shape leaf functional traits, soil microbial dynamics, and their association. However, the correlation between aboveground functional traits and belowground rhizosphere soil microorganisms of dominant tree species in mixed leguminous and non-leguminous forests remains unclear. In this study, the responses and correlations of leaf functional traits and rhizosphere soil microbial communities of Castanopsis hystrix Hook. f. & Thomson ex A. DC. across three forest types were investigated. A pure forest (PF) of C. hystrix was designated as control forest, while a leguminous mixed forest (LMF) consisting of C. hystrix and the leguminous species Acacia mangium Willd. as well as a non-leguminous mixed forest (NMF) comprising C. hystrix and the non-leguminous species Schima superba Gardner & Champ. served as experimental forests. Seven leaf functional trait indices were measured, and the high-throughput sequencing of soil microbial communities was included in the analysis. The results were as follows: Firstly, compared to the pure forest, the specific leaf area (SLA) of C. hystrix significantly decreased in both mixed forest types (p < 0.05). Additionally, in comparison to the pure forest, the leaf area (LA) and leaf organic carbon content (LOC) of C. hystrix significantly reduced (p < 0.05), whereas the leaf total phosphorus content (LTP) significantly increased in the non-leguminous tree species mixed forest (p < 0.01). The leaf dry matter content (LDMC), relative chlorophyll content (RCC), and leaf total nitrogen content (LTN) of C. hystrix exhibited no significant differences among the three forest types (p > 0.05). Secondly, neither the dominant phyla of rhizosphere soil microorganisms nor the bacterial richness and diversity had differences in the mixed forests. However, the richness and diversity of rhizosphere soil fungi significantly increased in the mixed forests, and those in the leguminous mixed forest exhibited more positive effects compared to those in the non-leguminous mixed forest. Finally, redundancy analysis (RDA) showed significant correlations between plant leaf functional traits and rhizosphere soil microorganisms. Specifically, LDMC, SLA, LTN, and LTP of C. hystrix showed significant correlations with differences in the structure of bacterial community (p < 0.05), and LTN was significantly correlated with differences in the structure of the fungal community (p < 0.05). In summary, we found that plant leaf functional traits and the community of rhizosphere soil microorganisms displayed significant differences in the mixed forests, and those mixed with leguminous trees may further enhance the assimilation processes by modifying the utilization of nutrients such as carbon, nitrogen, and phosphorus by plants and microorganisms. Meanwhile, our results support the interaction of physiological and ecological processes between the aboveground and belowground parts of C. hystrix. These findings emphasize the important roles of N₂-fixing leguminous trees and synergy of aboveground–belowground processes in establishing sustainable artificial forests. Full article

This study investigates the impact of natural gas pipeline leakage on the soil temperature field through numerical simulations. Physical and mathematical models were developed to analyze the temperature and flow field changes resulting from pipeline leaks. The study explores the influence of various leakage factors on the temperature distribution in the surrounding soil. Key findings include the identification of the buried pipeline temperature as a critical factor influencing the soil temperature gradient when surface temperatures are similar to the subsurface constant temperature. Upon leakage, the pressure distribution around the leak is symmetrical, with a higher pressure at the leak point, and the Joule–Thomson effect causes a rapid decrease in gas temperature, forming a permafrost zone. The study also reveals that increased transport pressure expands the permafrost area, with pressure playing a significant role in the temperature field distribution. Additionally, an increase in the leak orifice diameter accelerates the expansion of the permafrost area and reduces the time for temperature stabilization at monitoring points. Conversely, changes in the leak direction mainly affect the spatial distribution of the permafrost zone without significantly altering its size. The findings provide valuable insights for monitoring natural gas pipeline leaks through temperature field variations. Full article