Search Results (1,740)

Dry reforming of methane (DRM) offers a sustainable route to convert two major greenhouse gases—CH₄ and CO₂—into synthesis gas (syngas), enabling low-carbon hydrogen production and carbon utilization. This study applies fifteen machine learning (ML) regression models to simultaneously predict CH₄ conversion, CO₂ conversion, H₂ yield, and CO yield using a published dataset of 27 experiments with Ni/CaFe₂O₄-catalyzed DRM. The comparative evaluation covers linear, tree-based, ensemble, and kernel-based algorithms under a unified multi-output learning framework. Feature importance analysis highlights reaction temperature, CH₄/CO₂ feed ratio, and Ni metal loading as the most influential variables. Predictions from the top-performing models (CatBoost and Random Forest) identify optimal performance windows—feed ratio near 1.0 and temperature between 780–820 °C—consistent with thermodynamic and kinetic expectations. Although no new catalysts are introduced, the study demonstrates how ML can extract actionable parametric insights from small experimental datasets, guiding future DRM experimentation and process optimization for hydrogen-rich syngas production. Full article

To assess multi-energy complementarity and commercial development status in thermodynamic energy storage systems, this review systematically examines compressed air energy storage (CAES), compressed CO₂ energy storage (CCES), and Carnot battery (CB), focusing on principles, engineering demonstrations, and thermal integration. Their ability to integrate external heat, conduct combined cooling, heating and power (CCHP), or achieve high round-trip efficiency (RTE) through different pathway positions them as critical enablers for achieving net-zero emissions. Over 240 research articles retrieved from Web of Science and other databases, supplemented by publicly available reports published between 2020 and 2025, were systematically analyzed and synthesized. Current technologies demonstrate evolution from single-function storage to multi-energy hubs, with RTEs reaching 75% (CAES/CCES) and 64% (CB). Thermal integration significantly enhances RTEs. The CCES features a 100 MW/1000 MWh demonstration facility, concurrently necessitating accelerated distributed applications with high efficiency (>70%) and energy density (>50 kWh/m³). All three enable grid flexibility (China’s CAES network), industrial decarbonization (CCES carbon–energy depositories), and thermal integration (CB-based CCHP). These systems require >600 °C compressors and AI-optimized thermal management (CAES), high-pressure turbines and carbon–energy coupling (CCES), as well as scenario-specific selection and equipment reliability validation (CB) to achieve the targets of the Paris Agreement. Full article

Manganese (Mn) has emerged as a contaminant of concern due to its occurrence at concentrations exceeding regulatory limits in various environmental matrices, driven by both anthropogenic activities and natural geochemical processes. Although Mn is an essential micronutrient, excessive exposure poses risks to human health and ecosystems. This study investigates the potential application of Moringa oleifera seed pods, an agro-industrial byproduct, as low-cost biosorbents for Mn ion removal from aqueous solutions. Biosorbents were prepared from raw seed pods and chemically modified using NaOH and HCl. Surface characterization was performed using SEM, EDS, and FTIR techniques. Kinetic analysis indicated that Mn ion adsorption by all biosorbents followed a pseudo-second-order model, with equilibrium reached within 30 min. Among the tested materials, the alkali-treated biosorbent exhibited the highest removal efficiency (94%) under optimal conditions (288 K, pH 6.0, 60 min). Equilibrium data fitted both Langmuir and the Freundlich isotherms, with a maximum adsorption capacity of 7.64 mg g⁻¹ for alkali-treated pods and 6.00 mg g⁻¹ for the unmodified pods. Thermodynamic analysis revealed negative Gibbs free energy values, confirming the spontaneous nature of the biosorption process. Enthalpy values below 40 kJ mol⁻¹ (Pod_NA: 11.88 kJ mol⁻¹; Pod_AC: 1.08 kJ mol⁻¹; Pod_BA: 8.94 kJ mol⁻¹) suggest that physisorption is the predominant mechanism. These findings demonstrate the viability of Moringa oleifera pods as effective biosorbents for Mn ion remediation, supporting the valorization of agricultural waste within sustainable water treatment strategies. Full article

The present study showed that it is possible add value to eucalyptus harvest waste, obtained in large quantities, from the cellulose industries, without known economic use, for the production of an activated biochar. The biochar, produced from the impregnation of eucalyptus harvest waste with H₃PO₄, and subsequently pyrolyzed at 600 °C for 1 h, was successfully used as a bioadsorbent in the removal of paracetamol, an emerging pollutant present in wastewater. The biochar showed a high specific surface area with micro- and mesopores and functionalized surface. The optimal conditions for the removal of paracetamol achieve an efficiency around 88–93%. The Langmuir and the pseudo-first-order models best fit the experimental data, with a maximum adsorption capacity of approximately 27.8 mg g⁻¹, at 25 °C. The thermodynamic showed that adsorption occurred spontaneously, endothermally and randomly at the solid–liquid interface. In addition, the bioadsorbent showed excellent reusability and no significant difference in adsorption capacity was observed in more complex aqueous matrices. Thus, the activated biochar produced in this study proved to be an efficient, low-cost and environmentally friendly bioadsorbent, capable of removing paracetamol from contaminated water, with great potential for use in water treatment plants, on a large scale and economically, contributing to the improvement of water quality and minimizing residual biomass in the environment. Full article

BaTiO₃ (BT)-based lead-free ceramics are regarded as highly promising candidates for solid-state electrocaloric (EC) cooling devices due to their large spontaneous polarizations, shiftable Curie temperatures, and environmental friendliness. This review summarizes recent progresses in the design and optimization of BT-based EC ceramics. Key aspects include thermodynamic principles of the EC effect (ECE); structural phase transitions; and strategies such as constructing relaxor ferroelectrics, multi-phase coexistence, etc. Finally, future research directions are proposed, including the exploration of local microstructural evolution, polarization flip mechanisms, and bridging material design and device integration. This work aims to provide insights into the development of high-performance BT-based materials for solid-state cooling devices. Full article

Excessive phosphorus emissions are a significant driver of severe eutrophication in water bodies, and developing an efficient and cost-effective adsorbent for phosphorus removal is imperative. In this study, a Na-type zeolite was synthesized from coal gangue sourced from an open-pit mine in Xinjiang province, China. The synthesis process involved drying, crushing, alkali activation, aging, hydrothermal crystallization, and Na⁺ ion exchange. Orthogonal design identified the optimal synthesis parameters: an alkali-to-ash ratio of 1:1, aging at 20 °C for 12 h, and crystallization at 130 °C for 12 h. Aging time exerted the greatest influence on the phosphate removal efficiency. The optimized zeolite exhibited excellent phosphate adsorption performance, achieving a removal efficiency of up to 96% and a capacity of 16 mg/g. The adsorption kinetics followed both pseudo-first-order and pseudo-second-order models, indicating processes governed by combined physical and chemical mechanisms. Isotherm data fitting with Freundlich and Langmuir models suggested the presence of both homogeneous and heterogeneous active sites. Thermodynamic studies confirmed a spontaneous and endothermic process, increasingly favorable at higher temperatures. Characterizations via scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray fluorescence (XRF) spectroscopy, and Fourier transform infrared (FTIR) spectroscopy confirmed the formation of Na-type zeolite and revealed structural and compositional changes following phosphate adsorption. Aluminum and calcium binding played key roles in the chemical adsorption mechanisms. This work not only offers a high-efficiency, low-cost solution for phosphorus removal from wastewater but also provides a sustainable pathway for the valorization of coal gangue in the Zhundong area of Xinjiang, China. Full article

Dry ice, the solid form of carbon dioxide (CO₂), is widely used in cold chain logistics, industrial cleaning, and biomedical preservation. Its production, however, is closely linked to carbon capture, energy-intensive liquefaction, and solidification processes. This review critically evaluates and compares the existing methods of CO₂ capture, including chemical absorption, physical absorption, adsorption, and membrane-based separation as they pertain to dry ice production. This study further assesses liquefaction cycles using refrigerants such as ammonia and R744, highlighting thermodynamic and environmental trade-offs. Solidification techniques are examined in the context of energy consumption, process integration, and product quality. The comparative analysis is supported by extensive tabulated data on operating conditions, CO₂ purity, and sustainability metrics. This review identifies key technical and environmental challenges, such as solvent regeneration, CO₂ leakage, and energy recovery. Thus, it also explores emerging innovations, including hybrid cycles and renewable energy integration, to advance the sustainability of dry ice production. This, in turn, offers strategic insight for optimizing dry ice manufacturing in alignment with low-carbon industrial goals. Full article

Machine learning models and web-based tools have been developed for predicting key properties of imidazolium-based ionic liquids. Two high-quality datasets containing experimental density and viscosity values at 298 K were curated from the ILThermo database: one containing 434 systems for density and another with 293 systems for viscosity. Molecular structures were optimized using the GOAT procedure at the GFN-FF level to ensure chemically realistic geometries, and a diverse set of molecular descriptors, including electronic, topological, geometric, and thermodynamic properties, was calculated. Three support vector regression models were built: two for density (IonIL-IM-D1 and IonIL-IM-D2) and one for viscosity (IonIL-IM-V). IonIL-IM-D1 uses three simple descriptors, IonIL-IM-D2 improves accuracy with seven, and IonIL-IM-V employs nine descriptors, including DFT-based features. These models, designed to predict the mentioned properties at room temperature (298 K), are implemented as interactive applications on the atomistica.online platform, enabling property prediction without coding or retraining. The platform also includes a structure generator and searchable databases of optimized structures and descriptors. All tools and datasets are freely available for academic use via the official web site of the atomistica.online platform, supporting open science and data-driven research in molecular design. Full article

Given the multi-basin raw material base for coking that has been formed at most industry enterprises, there is an urgent need to optimize the component composition and improve the basic technological methods of coal raw material preparation, taking into account the petrographic characteristics of coal batches. A comprehensive study of the components included in a coke chemical enterprise’s coking raw material base was carried out. The work used standardized methods for studying coal and coal batches’ technological and plastic–viscous properties. The qualitative characteristics of coke were determined using physical–mechanical and thermochemical methods of studying standardized indicators: crushability (M₂₅), abrasion (M₁₀), reactivity (CRI), post-reaction strength (CSR), and specific electrical resistance (ρ). The results were analyzed using the licensed Microsoft Excel computer program. Based on the results of proximate, plastometric, and petrographic analyses of the studied coal samples and data from experimental industrial coking, proposals were made to optimize the component composition, properties of the coal batch, and technology for its preparation for coking. The established inverse dependence of Gibbs free energy (ΔG_f,total) on the reaction capacity of coke CRI and its direct reliance on its post-reaction strength CSR confirmed the feasibility of using ΔG_f,total as a thermodynamic predictive parameter for optimizing and compiling coal batches that produce less reactive, stronger coke. This made it possible to improve the quality indicators of metallurgical coke. Thus, according to the M₂₅ crushability index, the mechanical strength increased by 0.6%, and the M₁₀ abrasion decreased by 0.4%. Significant improvements in thermochemical properties and an increase in the orderliness of the carbon structure were recorded: the CRI reactivity decreased by 3.1%, the CSR post-reaction strength increased by 8.3%, and the specific resistance decreased by 8.4%. Full article

This study systematically investigated the dissolution equilibrium of lithium carbonate (Li₂CO₃) in mixed Na₂CO₃-NaCl aqueous solutions through isothermal dissolution experiments spanning 283.15–353.15 K. Precise solubility determinations were conducted using a gravimetric analysis under controlled thermodynamic conditions. The obtained solubility data were successfully correlated with the Extended Debye–Hückel (E-DH) model, yielding residual standard deviations below 0.09, which validates the model’s applicability in this ternary system. Both experimental observations and theoretical predictions confirmed that increasing the salt molality enhances the synergistic suppression of the Li₂CO₃ solubility through combined common-ion and salt effects. The thermodynamic analysis revealed the dissolution process to be exothermic (ΔH_d < 0), and entropy change dominates (ξ_S ≈ 78%), with negative entropy changes (ΔS_d < 0) indicating predominant hydration ordering effects. These mechanistic insights establish critical thermodynamic benchmarks for optimizing lithium carbonate precipitation processes in brine lithium extraction operations. Full article

This study examines scientific and technical solutions designed to enhance thermodynamic processes in modern aircraft turbine engines by utilizing heat exchangers. A comprehensive literature review informed the development of a conceptual design for a turbofan engine incorporating both an intercooler and a recuperator. The research included an original parametric and constrained optimization analysis conducted for two engine configurations as follows: one intended for narrow-body and the other for wide-body aircraft. The study focused on achieving the required thrust while enhancing efficiency. Results indicate that integrating heat exchangers can significantly reduce specific fuel consumption (SFC) and/or increase engine power or thrust. Moreover, the recovery of residual heat from exhaust gases through recuperation contributes to improved overall energy efficiency. The study also explores a novel cryogenic design that utilizes liquid hydrogen for cooling the intercooler, recuperator, and turbine. Although not modeled directly, this concept demonstrates the potential to increase the bypass ratio, further reduce SFC, and lower NO_x emissions. These findings highlight the promise of combined intercooling and recuperation strategies for improving both economic and environmental performance, with optimal system parameters dependent on aircraft class. The research aligns with ongoing efforts in mechanical engineering and aviation to enhance turbine engine efficiency through innovative thermal management solutions. Full article

Recently, an article was published in which a more accurate pre-screening method compared to MMFF for conformer distributions in flexible organic molecules was presented. However, experimental data on conformer distributions are almost completely lacking. Therefore, old experimental and computational work on the thermodynamic partition of DIPN isomers was revisited to compare the new method, corrected MMFF (cMMFF), with MMFF as a pre-screening tool. Next, the preliminary conformer distributions were used as input for higher-level QM calculations to yield more reliable conformer distributions. Generally, it was found that cMMFF yields smaller energy differences between DIPN isomers and conformers of a DIPN isomer than MMFF, in line with the results of DFT methods B3LYP and B3PW91, used in higher-level calculations. MP2 turned out to be a remarkable outlier, yielding even smaller energy differences both between DIPN isomers and conformers of a DIPN isomer. Preliminary conformer distributions of DIPN isomers obtained with MMFF and optimized with B3LYP and B3PW91 yielded excellent thermodynamic equilibrium partitions of DIPN isomers compared to the available experimental data. Preliminary conformer distributions of DIPN isomers obtained with cMMFF and optimized with B3LYP and B3PW91 performed less well. However, this seems due to a small effect on the energy (~4 kJ/mol) of the local geometry of the β-isopropyl group on naphthalene, which still strongly affects the thermodynamic equilibrium partitions. To obtain a more balanced judgement on the newly proposed method and the existing ones, more comparisons between experimental and computational data on small molecules with a higher degree of flexibility are needed. Full article

The low water solubility of sulfamethazine (SMT) limits its clinical efficacy, making it crucial to study techniques such as cosolvency to optimize pharmaceutical formulations. This study aimed to thermodynamically evaluate the solubility of SMT in {acetonitrile (MeCN) + ethanol (EtOH)} cosolvent mixtures over a temperature range of 278.15 to 318.15 K in order to understand the molecular interactions that govern this process. SMT solubility in the mixtures was measured using a flask-shaking method. The solid phases were analyzed using differential scanning calorimetry (DSC) to rule out polymorphisms. Using the Gibbs–van’t Hoff–Krug model, we calculated the apparent thermodynamic functions of the solution and mixture from the obtained data. The results showed that solubility increased almost linearly with MeCN fraction and temperature, indicating that MeCN is a more efficient solvent and that the process is endothermic. Thermodynamic analysis revealed that dissolution is an endothermic process with favorable entropy for all compositions. The higher solubility in MeCN is attributed to the lower energetic cost required to form the solute cavity compared to the high energy needed to disrupt the hydrogen bond network of ethanol. This behavior can be explained by an enthalpy–entropy compensation phenomenon. This phenomenon provides an essential physicochemical basis for designing pharmaceutical processes. Full article

Background/Objectives: The intranasal (IN) route of administration is a promising non-invasive approach for brain targeting, bypassing the blood–brain barrier and enhancing bioavailability. Citalopram hydrobromide (CT), a widely prescribed sparingly water-soluble selective serotonin reuptake inhibitor (SSRI), faces challenges with oral and intravenous administration, including delayed onset, adverse effects, and patient compliance issues. Methods: This study aimed to develop a novel thermoresponsive polymeric micelle (PM) system based on Pluronic^® copolymers (Pluronic F127 and Poloxamer 188) improving CT’s solubility, stability, and nasal permeability for enhanced antidepressant efficacy. A preliminary study was conducted to select the optimized formulation. The preparation process involved using the thin-film hydration method, followed by freeze-drying. Comprehensive evaluations of optimized formulation characteristics included Z-average, polydispersity index (PdI), thermal behavior (lower critical solution temperature, LCST), encapsulation efficiency, X-ray powder diffraction (XRPD), thermodynamic solubility, and biological stability. Additionally, in vitro CT release and CT permeability in nasal conditions were studied. Stability under storage was also evaluated. Results: The optimized CT-PM formulation showed nanoscale micelle size (Z-average of 31.41 ± 0.99 nm), narrow size distribution (polydispersity index = 0.241), and a suitable thermal behavior for intranasal delivery (lower critical solution temperature (LCST) ~31 °C). Encapsulation efficiency reached approximately 90%, with an amorphous structure confirmed via XRPD, leading to a 95-fold increase in CT solubility. The formulation demonstrated appropriate biological and physical stability. In vitro studies showed a 25-fold faster CT release from optimized formulation compared to the initial CT, while CT-PM permeability in nasal conditions increased four-fold. Conclusions: This novel nanoscale thermosensitive formulation is a value-added strategy for nasal drug delivery systems, offering enhanced drug solubility, rapid drug release, stability, and improved permeability. This smart nanosystem represents a promising platform to overcome the limitations of conventional CT administration, improving therapeutic outcomes and patient compliance in depression management. Full article

Controlling dissolved nitrogen is critical to meeting increasingly stringent steel quality targets, yet the variable kinetics of gas absorption and removal across production stages complicate real-time decision-making. Leveraging a total of 291 metal samples, the research applied ordinary least squares (OLS) regression, enhanced by cointegration diagnostics, to develop four stage-specific models covering pig iron after desulfurization, crude steel in the basic oxygen furnace (BOF) before tapping, steel at the beginning and end of secondary metallurgy processing. Predictor selection combined thermodynamic reasoning and correlation analysis to produce prediction equations that passed heteroscedasticity, normality, autocorrelation, collinearity, and graphical residual distribution tests. The k-fold cross-validation method was also used to evaluate models’ performance. The models achieved an adequate accuracy of 77.23–83.46% for their respective stages. These findings demonstrate that statistically robust and physically interpretable regressions can capture the complex interplay between kinetics and the various processes that govern nitrogen pick-up and removal. All data are from U. S. Steel Košice, Slovakia; thus, the models capture specific setup, raw materials, and production practices. After adaptation within the knowledge transfer, implementing these models in process control systems could enable proactive parameter optimization and reduce laboratory delays, ultimately minimizing excessive nitrogenation in finished steel. Full article