Search Results (711)

This work investigates the synthesis, thermodynamic phase stability and microstructural, mechanical and tribological behavior of the CrFeMoV alloy system and its Al-modified derivatives, CrFeMoV-Al2 and CrFeMoV-Al6, which belong to the family of high- and medium-entropy alloys. The studied systems were produced via Vacuum Arc Melting (VAM), followed by a comprehensive characterization. Thermodynamic and geometric phase-formation models were employed to predict the formation of BCC/Β2 solid solutions and the potential emergence of σ-type intermetallic compounds. An ML model was also employed to further predict elemental interactions and phase evolution. These predictions were experimentally confirmed via X-ray diffraction analysis, which verified the presence of a BCC matrix in all compositions, the presence of σ-phase precipitates whose volume fraction systematically reduced with Al inclusion and the gradual increase in the B2 phase with the increase in the Al content. Scanning electron microscopy and EDX analyses uncovered noticeable dendritic segregation, with Mo and Fe enrichment in dendrite cores and in interdendritic regions, respectively. Cr, V, and Al were more uniformly distributed. Mechanical property data derived by micro hardness testing demonstrated a high hardness of 816 HV for the base alloy, ascribed to σ-phase strengthening, followed by a progressive reduction in this value to 802 HV and 756 HV in Al-containing alloys due to the attenuation of σ-phase formation and the gradual increase in the B2 phase. Dry sliding wear results unveiled a positive correlation between wear resistance and hardness, confirming the beneficial role of intermetallic strengthening. Finally, nanoindentation tests shed light on the nanoscale mechanical response, confirming the trends observed at the microscale. Overall, the combination of thermodynamic modeling and experimental analysis provide a robust framework for understanding phase stability, microstructural evolution, and mechanical performance in Al-alloyed CrFeMoV high-entropy systems, while highlighting the potential of controlled Al additions to tailor microstructure and properties. Full article

This classroom-based case study examines how an AI-mediated Socratic dialogue, implemented through ChatGPT, can support students’ engagement and perceived learning in undergraduate thermodynamics. Conducted in a first-year engineering physics course at a private university in northern Mexico, the activity invited small student groups to interact with structured prompts designed to promote inquiry, collaboration, and reflective reasoning about the adiabatic process. Rather than functioning as a source of answers, ChatGPT was intentionally positioned as a mediating scaffold for Socratic questioning, prompting students to articulate, examine, and refine their reasoning. A mixed-methods approach was employed, combining a 10-item Likert-scale survey with construct-level statistical analysis of two focal dimensions: perception of learning and engagement, including an exploratory comparison by gender. Results indicated consistently high levels of perceived learning and engagement across the cohort, with average scores above 4.5 out of 5. At the construct level, no statistically significant gender differences were observed, although a single item revealed higher perceived learning among female students. Overall, the findings suggest that the educational value of ChatGPT in this context emerged from its integration within a Socratic, inquiry-oriented pedagogical design, rather than from the technology alone. These results contribute to ongoing discussions on the responsible and pedagogically grounded integration of generative AI in physics education and align with Sustainable Development Goal 4 (Quality Education). Full article

Power transformers are critical assets in power systems, and their reliable operation is essential for grid stability. Conventional fault diagnosis methods suffer from delayed response and limited adaptability, while existing artificial intelligence-based approaches face challenges related to data heterogeneity, limited interpretability, and weak integration of physical mechanisms. To address these issues, this paper proposes a physics-informed enhanced transformer-based framework for power transformer fault diagnosis. A unified temporal representation scheme is developed to integrate heterogeneous monitoring data using Dynamic Time Warping and physics-guided feature projection. Physical priors derived from thermodynamic laws and gas diffusion principles are embedded into the attention mechanism through multi-physics coupling constraints, improving physical consistency and interpretability. In addition, a multi-task diagnostic strategy is adopted to jointly perform fault classification, severity assessment, and fault localization. Experiments on 3000 samples from 76 power transformers demonstrate that the proposed method achieves high diagnostic accuracy and superior robustness under noise and interference, indicating its effectiveness for practical predictive maintenance applications. Full article

A systematic density functional theory (DFT) and time-dependent DFT (TD-DFT) investigation of aluminum phosphide (Al_xP_x) nanoparticles with diverse dimensionalities and geometries is presented. Starting from a cubic-like Al₄P₄ building block, a series of one-dimensional (1D) elongated, two-dimensional (2D) exotic, and extended sheet-like nanostructures was constructed, enabling a unified structure–property analysis across size and topology. Optical absorption and infrared (IR) vibrational spectra were computed and correlated with geometric motifs, revealing pronounced shape-dependent tunability. Compact and highly interconnected 2D architectures exhibit red-shifted absorption and enhanced vibrational polarizability, whereas elongated or low-connectivity motifs lead to blue-shifted optical responses and stiffer vibrational frameworks. Benchmark comparisons indicate that CAM-B3LYP excitation energies closely reproduce reference EOM-CCSD trends for the lowest singlet states. Binding energy and HOMO-UMO gap analyses confirm increasing thermodynamic stability with size and dimensionality, alongside topology-driven electronic modulation. These findings establish AlP nanostructures as highly tunable platforms for optoelectronic and vibrationally active applications. Full article

Candidozyma auris (formerly Candida auris) is an emerging multidrug-resistant fungal pathogen with confirmed cases in over 30 countries. Although whole-genome sequencing (WGS) analysis defined distinct clades during characterization of underlying genetic mechanism behind multidrug resistance, Clade II remains under-evaluated. In this study, a three-level comparative genomic strategy (Global, Clade, Phenotype) was employed by integration of unbiased genome-wide comparative SNP screening (GATK v4.1.9.0), targeted BLAST profiling (BLAST+ v2.17.0), and in silico protein analysis (ColabFold v1.5.5; DynaMut2 v2.0) for systematic evaluation of mechanisms of antifungal resistance in thirty-nine Clade II C. auris clinical isolates and fourteen reference strains. Global and clade-level analyses confirmed that all the clinical isolates belong to Clade II, according to phylogenetic clustering and mating type locus (MTL) conservation. At the phenotype level, a distinct subclade of fluconazole-resistant mutants was identified to have a heterogenous network of mutations in seven key enzymes associated with cell membrane dynamics and the metabolic stress response. Among these, four core mutations (TAC1B, CAN2, NIC96, PMA1) were confirmed as functional drivers based on strict criteria during multitier in silico protein analysis: cross-species conservation, surface exposure, active site proximity, thermodynamic stability, and protein interface interaction. On the other hand, three high-level fluconazole-resistant clinical isolates (≥128 μg/mL) that lacked these functional drivers were subjected to comprehensive subtractive genomic profiling analysis. The absence of coding mutations in validated resistance drivers, yeast orthologs, and convergent variants suggests that there is an alternative novel non-coding or regulatory mechanism behind fluconazole resistance. These findings highlight Clade II’s evolutionary divergence into two distinct trajectories towards the development of a high level of fluconazole resistance: canonical protein alteration versus regulatory modulation. Full article

Understanding the evolution of the atmospheric boundary layer height (BLH) is essential for characterizing air–surface exchange and air pollution processes. This study investigates the consistency and applicability of three BLH retrieval methods based on multi-source remote sensing observations at Beijing Southern Suburb station during autumn–winter 2023. Using Doppler wind lidar (DWL) and microwave radiometer (MWR) data, the Haar wavelet covariance transform (HWCT), vertical velocity variance (Var), and parcel methods were applied, and 10 min averages were used to suppress short-term fluctuations. Statistical analysis shows good overall consistency among the methods, with the strongest correlation between HWCT and Var method (R = 0.62) and average systematic positive bias of 0.4–0.6 km for the parcel method. Case studies under clear-sky, cloudy, and hazy conditions reveal distinct responses: HWCT effectively captures aerosol gradients but fails under cloud contamination, the Var method reflects turbulent dynamics and requires adaptive thresholds, and the Parcel method robustly describes thermodynamic evolution. The results demonstrate that the three methods are complementary in capturing the material, dynamic, and thermodynamic characteristics of the boundary layer, providing a comprehensive framework for evaluating BLH variability and improving multi-sensor retrievals under diverse meteorological conditions. Full article

This work investigates methods for predicting low-cycle fatigue life by employing new energy-based fatigue damage measures. The primary goal of this research is to evaluate whether fatigue life can be predicted based on an energy accumulation graph, proposed as a generalization of the isodamage lines concept. The efficiency of fatigue life predictions using this approach, derived from the empirical linear Palmgren–Miner hypothesis, is compared against the physically grounded Unified Mechanics Theory thermodynamic approach, which allows for general understanding of material degradation, in contrast to empirical approaches. The study also accounts for the influence of anisotropy resulting from the sheet rolling process on the fatigue response of S420M steel. Samples were tested in orientations both parallel to the rolling direction and perpendicular to the sheet surface. Microstructural analysis revealed a visible banded structure in the perpendicular samples, which is a consequence of anisotropy. The fatigue life of samples taken perpendicular to the sheet surface was lower than that of parallel samples. Verification of the linear Palmgren–Miner damage summation hypothesis, using both the classical fatigue chart and the cumulative energy chart, resulted in calculated fatigue life consistently higher than the experimental fatigue life in all cases. The reduction in fatigue life ranged from 40% (for total strain amplitude equal to 1.0%) to almost 290% for a strain amplitude of 0.25%. A comparative analysis of the unit loop energy shows that at all tested levels of strain amplitude, the unit loop energy of parallel samples is higher than that of samples perpendicular to the surface. Full article

Direct hydroxylation of benzene to phenol using hydrogen peroxide is a cornerstone of sustainable green chemistry. This paper presents the results of a stability study of an iron-containing mordenite catalyst in the liquid-phase hydroxylation of benzene to phenol with a 30% aqueous hydrogen peroxide solution. The study utilizes a combination of catalytic activity measurements, dynamic light scattering (DLS), and electron paramagnetic resonance (EPR) spectra. The system is initially shown to exhibit high phenol selectivity; however, over time, DLS measurements indicate aggregation of the catalyst particles with an increase in the average particle diameter from 1.8 to 2.6 μm and the formation of byproducts–dihydroxybenzenes. Iron is present predominantly as magnetite nanoparticles (Fe₃O₄) ~10 nm in diameter, stabilized on the outer surface of mordenite, with minor leaching (<10%) due to the formation of iron ion complexes with ascorbic acid as a result of the latter’s interaction with magnetite particles. Using a thermodynamic approach based on the Ulich formalism (first and second approximations), it is shown that the reaction of benzene hydroxylation H₂O₂ in the liquid phase is thermodynamically quite favorable (ΔG° = −(289–292) kJ·mol⁻¹ in the range of 293–343 K, K = 1044–1052). It is shown that ascorbic acid acts as a redox mediator (reducing Fe³⁺ to Fe²⁺) and a regulator of the catalytic medium activity. The stability of the catalytic system is examined in terms of the Lyapunov criterion: it is shown that the total Gibbs free energy (including the surface contribution) can be considered as a Lyapunov functional describing the evolution of the system toward a steady state. Ultrasonic (US) treatment of the catalytic system is shown to redisperse aggregated particles and restore its activity. It is established that the catalytic activity is due to nanosized Fe₃O₄ particles, which react with H₂O₂ to form hydroxyl radicals responsible for the selective hydroxylation of benzene to phenol. Full article

This article reconceptualizes entropy not as a metaphysical substance but as a structural constraint that shapes the formation, energetic cost, and durability of records. It links the coarse-grained—and typically irreversible—flow of time to questions of moral responsibility and divine justice. Drawing on the second law of thermodynamics, information theory, and contemporary cosmology, it advances an analogical and operational framework in which actions are accountable in an analogical sense insofar as they leave energetically costly traces that resist erasure. Within a Qur’ānic metaphysical horizon, concepts such as kitāb (Book), ṣaḥīfa (Record), and tawba (Repentance) function as structural counterparts to informational inscription and revision, without reducing theological meaning to physical process. In contrast to Kantian ethics, which grounds moral law in rational autonomy, the Qurʾān situates responsibility within the irreversible structure of time. Understood in this way, entropy is not a threat to coherence but a condition for accountability. By placing the Qurʾānic vision in dialog with modern science and theology, the article contributes to broader discussions on justice, agency, and the metaphysics of time within the science–religion discourse. Full article

Nanoscopic quantum dots exhibit discrete energy spectra and size- and shape-dependent thermal properties that cannot always be adequately described within the conventional Boltzmann–Gibbs statistical framework. In systems with strong confinement, finite size, and reduced symmetry, deviations from extensivity may emerge, affecting the occupation of energy levels and the resulting thermodynamic response. In this context, this work elucidates how GaAs quantum dot geometry, external electric fields, and nonextensive statistical effects jointly influence the thermal response of quantum dots with different geometries—cubic, cylindrical, ellipsoidal, and pyramidal. These energy levels are calculated by solving the Schrödinger equation under the effective mass approximation, employing the finite element method for numerical computation. These energy levels are then incorporated into an iterative numerical procedure to calculate the specific heat for different values of the nonextensivity parameter, thereby enabling exploration of both extensive (Boltzmann–Gibbs) and nonextensive regimes. The results demonstrate that the shape of the quantum dots strongly influences the energy spectrum and, consequently, the thermal properties, producing distinctive features such as Schottky-type anomalies and geometry-dependent shifts under an external electric field. In subextensive regimes, a discrete behavior in the specific heat emerges due to natural cutoffs in the accessible energy states. In contrast, in superextensive regimes, a smooth, saturation-like behavior is observed. These findings highlight the importance of geometry, external-field effects, and nonextensive statistics as complementary tools for tailoring the energy distribution and thermal response in nanoscopic quantum systems. Full article

The elimination of toxic and long-lasting dyes like crystal violet (CV) from wastewater continues to be a major environmental challenge. Considering this, in this study, a novel amine-modified adsorbent was synthesized by functionalizing ZIF-67 with phosphorylethanolamine (PEA@ZIF-67) nanocomposite to enhance dye removal efficiency. Comprehensive characterization of PEA@ZIF-67 nanocomposite using FTIR, XRD, TGA, and BET techniques confirmed the successful incorporation of PEA into ZIF-67 without compromising the structural integrity of the ZIF-67. The BET specific surface area of PEA@ZIF-67 nanocomposite was noted to be 145.3 m²/g. Furthermore, the application of PEA@ZIF-67 nanocomposite for CV adsorption was investigated and optimized using the Response Surface Methodology (RSM) technique, with the adsorbent dosage, initial dye concentration, and temperature as the operational variables. Under optimized conditions, q_max was 4348 mg/g. Adsorption kinetic studies showed the Avrami model to best fit the respective CV adsorption results, suggesting a heterogeneous and time-dependent mechanism. On the other hand, the Redlich–Peterson adsorption isotherm, which signifies a hybrid adsorption behavior, was noted to be effective. The thermodynamic studies confirmed that the CV adsorption onto PEA@ZIF-67 is spontaneous, endothermic, and entropy-driven. The post-adsorption FTIR and XRD analyses indicated that the used PEA@ZIF-67 was stable, thus supporting its reuse capability. Full article

Although the literature is rich in studies of indoor thermal comfort, there is a lack of research on outdoor thermal comfort, despite its importance in response to global warming and the rise of urban heat islands. Physics models addressing spatial (urban energy form, green areas) and temporal (climate variability) factors are urgently needed. This study proposes a useful method for outdoor comfort evaluation at a district scale, based on the energy form of built-up areas and hyperlocal climatic conditions. It enables the determination of distributed Physiological Environmental Temperature values at a district scale, assessing the greenery effect and mutual radiative exchanges. Applied to a case study in Florence, Italy, it integrates multiple measurement techniques. The main results highlight the model’s ability to evaluate outdoor thermal perception through the new identified indicator of Virtual Physiological Environmental Temperature (PET*) spread, ranging from 23.5 to 101.0 °C, specifically referring to the worst climatic conditions inside an urban canyon in relation to different real scenarios. The results confirm the method’s effectiveness as a tool for thermodynamics and planning for the well-being of an urban built-up environment. It offers useful support for sustainability and human-centric design, oriented to UHI mitigation and climate change adaptation strategies. Full article

Coal slime, a byproduct of coal processing with high ash content, poses significant challenges in terms of its efficient separation and resource utilization due to its fine particle size and complex composition. This study aims to optimize the oil agglomeration process for coal slime separation through systematic parameter investigation and predictive modeling. Response surface methodology (RSM) was employed to analyze the individual and interactive effects of pulp density, oil dosage, and agitation rate on three key performance indicators: combustible recovery, efficiency index, and ash rejection. Meanwhile, an artificial neural network (ANN) was developed to establish a robust prediction model for the efficiency index. The novelty of this work lies in the integration of thermodynamic analysis, multi-objective optimization, and machine learning approaches. The key findings include the identification of dodecane as the optimal bridging liquid due to its intermediate carbon chain length that balances interfacial tension and wettability. Under optimized conditions (14% pulp density, 22% oil dosage, and 1600 r/min), the process achieved a combustible recovery of 91.49%, ash rejection of 61.58%, and efficiency index of 53.07%. The ANN model demonstrated superior predictive capability with an overall R² of 0.9659 and RMSE of 1.12. This work provides comprehensive guidelines for the design, optimization, and scale-up of coal slime oil agglomeration processes in industrial applications. Full article

The increasing share of renewable energy sources (RES) in modern power systems necessitates the development of efficient, large-scale energy storage technologies capable of mitigating generation variability. Liquid Air Energy Storage (LAES), particularly in its adiabatic form, has emerged as a promising candidate by leveraging thermal energy storage and high-pressure air liquefaction and regasification processes. Although LAES has been widely studied, the impact of ambient temperature on its performance remains insufficiently explored. This study addresses that gap by examining the thermodynamic response of an adiabatic LAES system under varying ambient air temperatures, ranging from 0 °C to 35 °C. A detailed mathematical model was developed and implemented in Aspen Hysys to simulate the system, incorporating dual refrigeration loops (methanol and propane), thermal oil intercooling, and multi-stage compression/expansion. Simulations were conducted for a reference charging power of 42.4 MW at 15 °C. The influence of external temperature was evaluated on key parameters including mass flow rate, unit energy consumption during liquefaction, energy recovery during expansion, and round-trip efficiency. Results indicate that ambient temperature has a marginal effect on overall LAES performance. Round-trip efficiency varied by only ±0.1% across the temperature spectrum, remaining around 58.3%. Mass flow rates and power output varied slightly, with changes in discharging power attributed to temperature-driven improvements in expansion process efficiency. These findings suggest that LAES installations can operate reliably across diverse climate zones with negligible performance loss, reinforcing their suitability for global deployment in grid-scale energy storage applications. Full article

Tablet film coating is governed by three interrelated phenomena, namely, tablet mixing, coating-liquid spraying, and liquid evaporation, which dominate the critical quality attributes ($CQAs$) of the final product. This review examines how differences in coater design, key process parameters, and quality control strategies impact these phenomena and ultimately affect inter-tablet and intra-tablet coating variability. Two complementary approaches for understanding and optimizing the process are evaluated. The experimental approach, involving Design of Experiments (DoE), retrospective data analysis, and advanced Process Analytical Technology ($PAT$), provides empirical insight into factor–response relationships and enables real-time quality assurance. Simultaneously, model-based approaches, including thermodynamic, spray-dynamics, and particle-dynamics modelling, offer mechanistic understanding of heat and mass transfer, droplet deposition patterns, and tablet motion. Although these sub-models have advanced considerably over the years, a predictive model that treats the coating process in its entirety is still missing. Overall, this review underscores that future advancements will require integrating experimental and model-based methodologies to achieve robust, quality-driven, and predictive control of tablet film coating processes. Full article