Boron-containing minerals have attracted significant attention in ceramic glaze systems due to their strong influence on melting behavior and glass structure. In this study, the effect of colemanite addition on opaque sanitaryware glazes was systematically investigated in terms of thermal behavior, phase evolution, microstructure, and functional and thermal properties. A standard industrial glaze composition was modified by incorporating 0.3–5 mass
The main focus of the current study is to explore the rate of heat transfer in MHD hybrid nanofluid (Cu–SiO2/H2O) Darcy–Forchheimer flow across the 3D rotating stretched sheet with dynamics of magnetic field, thermal radiation, shape of nanoparticles, suction, and convective boundary conditions. Currently, the hybrid nanofluid utilized for investigation is made up of copper (Cu) and silicon dioxide (SiO2) and water (H2O) as base fluid. The heat exchanger system, cooling system, different medical fields, and agriculture field are applications of hybrid nanofluid. The physical flow of problem is defined in the form of partial differential equations (PDEs). These systems of PDEs are converting in the system of ordinary differential equations (ODEs) through suitable similarity variables. These ODEs through bvp4c technique with package of MATLAB were graphically and numerically solved. When the higher of λ ,M,Fr, Po and S impact on the fluid velocity distribution along with both x-component are reduce but y- component are grow. The influences on the temperature profile raise with boosting the λ , M,Rd, n , and S. Then, when comparing the current findings to those of the previous, there is a strong correlation.
This study aims to investigate the relationship between heat transfer, thermal stresses, and temperature-dependent material degradation in cargo parachutes. The study evaluates how woven textile products used in parachute systems behave in relation to temperature. Considering that material degradation is a process that develops under combined mechanical and thermal effects, a theoretical temperature-dependent aging framework based on the Arrhenius relationship is presented. The study was conducted specifically with woven textiles designed at Erciyes University Aviation Application and Research Center (ERHAM). The temperature-dependent behavior of these specially designed woven fabrics was evaluated. The analyses were performed in the ANSYS Workbench environment using a one-way sequential Fluent–Mechanical FSI (Fluid–structure interaction) approach. The study lays the groundwork for a better understanding of the temperature-dependent mechanical strength of cargo parachutes before experimental data are obtained. In addition to providing a systematic framework for understanding the performance of parachute fabrics under thermal loads, the results obtained provide a roadmap for future experimental studies. This method is an important step in supporting cargo parachute design, durability evaluation, and reliability assessments.
The thermal stability of CL-20-based insensitive explosives has profound implications for their future applications. This study systematically investigates the thermal decomposition behavior, kinetic characteristics, and thermal stability of CL-20-based insensitive explosives by coupling thermal analysis results with the Semenov model. The results indicate that due to the synergistic effect of ammonium perchlorate (AP) with CL-20 and aluminum powder, the composite system exhibits a singular exothermic behavior. The activation energies calculated using the Kissinger method and Flynn–Wall–Ozawa (FWO) method are 159.32 kJ mol−1 and 163.82 kJ mol−1, respectively, which are lower than the 207±18 kJ mol−1 for pure CL-20. Due to the significant kinetic compensation effect between lnA and E, the activation energy calculated based on adiabatic acceleration calorimetry (ARC) is 408.23 kJ mol−1, which is significantly higher than that calculated by differential scanning calorimetry (DSC). Based on DSC and ARC, the self-accelerating decomposition temperatures (TSADT) are determined to be 178.86 °C and 175.45 °C, respectively, which are very close to the actual thermal runaway temperature of the sample (190 °C), with relative deviations of 5.86
7H-Benz[de]anthracen-7-one, commonly known as benzanthrone (BA), is a fluorescent dye, which is recognised for its strong luminescence and high photostability. A wide range of BA-based derivatives has attracted increasing attention in material research due to potential application possibilities in forensic science, anti-counterfeiting technologies, optical materials, biotechnology, material labelling, as well as in the textile and polymer industries. While recent studies have primarily focused on the synthesis and characterisation of the molecular structure and optical properties of various BA-based derivatives, information regarding their thermal stability remains limited, which is essential for future industrial processing steps. Therefore, the present work focuses for the first time on the systematic characterisation of thermal processes and their influence on the structure and luminescence behaviour of BA and its derivatives with various functional groups using a combination of several physico-chemical analytical techniques. The melting points and decomposition temperatures of commercially available BA and 3-bromobenzanthrone (3-BrBA), along with synthesised 3-nitrobenzanthrone (3-NO2BA) and 3-aminobenzanthrone (3-NH2BA), were determined using thermogravimetry-differential scanning calorimetry (TG-DSC). The gaseous compounds, which were released during heating up to 900 °C in different atmospheres, were analysed using Fourier transform infrared (FTIR) spectroscopy. Subsequently, thermal annealing was performed at selected temperatures near or higher than the determined melting points of these BA-based compounds in different atmospheres (air, nitrogen and vacuum). Characterisation of these compounds before and after annealing included analysis of structure using attenuated total reflectance (ATR) – FTIR spectroscopy and evaluation of luminescence behaviour using fluorescence spectroscopy. The obtained ATR-FTIR spectra showed no significant changes in the structure of BA and its derivatives after annealing up to complete thermal decomposition, regardless of the applied atmosphere. However, in the cases of 3-NH2BA and 3-NO2BA, annealing in air led to visible differences in luminescence behaviour, which suggests the formation of more emissive compounds through thermal decomposition and oxidation processes.
This study investigates the effect of heating rate on the oxidation behavior of waste tungsten carbide (WC) using non-isothermal thermogravimetric analysis (TGA). Tungsten oxide formation through high-temperature oxidation was systematically analyzed at different heating rates (5, 10, 20, and 40 °C min−1) under an air atmosphere. The kinetic parameters were evaluated using four model-free iso-conversional methods—Flynn–Wall–Ozawa (FWO), Kissinger–Akahira–Sunose (KAS), and Starink together with the model-fitting Coats–Redfern (CR) approach. The calculated average activation energy values were found to be 231.1, 229.1, and 229.5 kJ mol−1 for FWO, KAS, and Starink methods, respectively, showing good agreement among the models. Reaction mechanism analysis revealed a transition from reaction-controlled kinetics at low heating rates (5 °C min−1) to diffusion-controlled behavior at higher heating rates (20–40 °C min−1). Structural and morphological characterization was performed using XRD, Raman spectroscopy, SEM, and EDS analyses. The results confirmed the formation of tungsten oxide phases after oxidation. The positive activation enthalpy indicates that energy input is required to reach the transition state, confirming the kinetically controlled nature of the oxidation process. The findings provide useful insights for the recycling and thermal processing of waste tungsten carbide materials.
Polymorphism and its extended form, pseudopolymorphism, significantly affect the physicochemical properties, thermal stability, and potential pharmaceutical performance of biologically active compounds. Oxicams are a class of nonsteroidal anti-inflammatory drugs (NSAIDs) widely used in clinical practice; however, they are associated with a range of adverse effects. Consequently, there is ongoing interest in developing new derivatives with improved safety profiles. Moreover, owing to their structural flexibility and ability to form intramolecular hydrogen bonds and tautomeric structures, oxicam derivatives represent an interesting class of compounds exhibiting diverse solid-state behavior. In this work, a new arylpiperazine oxicam derivative was obtained as two distinct crystalline forms and characterized using spectroscopic methods (1H NMR, 13C NMR, ESI–MS, and FTIR) together with X-ray powder diffraction (XRPD). The results confirmed that the two forms differ in crystal packing and intermolecular interactions despite retaining the same molecular structure. Their thermal behavior was investigated using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA). The results demonstrated that form I is the thermodynamically stable form, whereas form II is a pseudopolymorphic form incorporating ethanol molecules during crystallization. These findings provide insights into the relationship between solvation and crystal packing in novel oxicam derivatives and contribute to a better understanding of solid-state transformations in pharmaceutically relevant molecules.
This study evaluated the use of the CALPRESDAT SN 20132 scanning microcalorimeter for studying aqueous surfactant systems under slow temperature-scanning conditions. Pure water and an aqueous sodium dodecyl sulfate (SDS) solution were used as model systems to determine whether the instrument could distinguish differences in their calorimetric signals. The measurements showed a stable instrumental baseline and revealed additional thermal effects in the SDS solution within the temperature range of approximately 295–300 K that were absent from the corresponding water measurement. These observations demonstrate that the instrument can distinguish small thermal differences between aqueous systems of different composition. Because only one SDS concentration was investigated and no complementary experimental techniques were used, the observed thermal effects cannot be interpreted unambiguously. The results provide a basis for future studies involving a wider range of surfactant types, concentrations, independent control of thermodynamic variables and complementary physicochemical techniques.
In the context of the global energy crisis and the Carbon Peak and Carbon Neutrality Goals, it has become an urgent task to seek efficient and environmentally friendly refrigeration technology. As a refrigeration scheme that can be driven by low-grade heat sources such as solar energy and industrial waste heat, ejector refrigeration technology has shown enormous potential due to its simple structure, reliable operation, environmental protection, and energy saving. This paper systematically reviews the recent research and development of ejector refrigeration technology in ejector and refrigerant in recent years, and combs the recent research progress of different ejector refrigeration systems from different classification methods. Finally, it points out the challenges faced by the current research and looks forward to the development direction of future research. This review aims to provide readers with an overview of recent theoretical and experimental studies on ejector refrigeration systems and help readers understand and sort out relevant research progress.
The motivation for the present research stems from the pressing need for cleaner, more efficient energy systems in heavy-duty engines. A naturally aspirated single-cylinder diesel engine configuration is operated at an engine speed of 910 rpm and a 4.05 bar load condition in dual-fuel mode. The study was performed using ANSYS Forte, a 3D computational software to measure the combustion, performance, and emission characteristics of a heavy-duty engine. In the present study, along with natural gas, hydrogen gas was introduced through port injection in a range of 0–45
Concentrated solar power (CSP) has emerged as a potential desalination technology from the renewable energy barrel. Unlike the old-fashioned ways that consume a huge amount of fossil fuel, CSP is a sustainable and environmentally friendly alternative. CSP-based desalination systems that employ multi effect distillation, multistage flash and reverse osmosis technologies use the sun's energy to produce potable water from saline sources. This paper gives an overview of the latest developments in CSP-based desalination technologies. It discusses performance, identifies problems and addresses the combination of these systems with various desalination processes. Although there are many studies concerning single CSP systems, many issues of a systematic comparison of different systems and a hybrid integration of different renewable energy technologies as well as long-term sustainability under different environmental conditions are still undiscovered. Additionally, high initial costs and inefficiencies from scaling and environmental factors are major obstacles to widespread adoption. The review brings out key technological, economic and environmental challenges. It provides significant information for the improvement needs in the CSP desalination systems. Novel strategies are introduced, such as the hybrid systems with combination of CSP and other renewable sources, the use of advanced materials to increase efficiency, and optimization of operational parameters. The results highlight the need for further studies of cost reduction techniques, system optimization and large-scale implementation. In conclusion, this paper shows the importance of the CSP-based desalination in solving the water shortage problem in the world. It describes a roadmap for future developments in this field.
The rapidly increasing global demand for cooling has intensified the need to transition from conventional vapor compression systems to sustainable and carbon–neutral alternatives. Adsorption Refrigeration Systems (ARS) have gained significant attention due to their ability to utilize low-grade waste heat or renewable energy sources while employing environmentally benign refrigerants. However, their large-scale deployment remains limited by the relatively low performance of conventional adsorbent–refrigerant working pairs. This review provides a critical assessment of recent advancements in composite adsorbents and advanced working pairs aimed at improving ARS efficiency and feasibility. Traditional systems, particularly silica gel water pairs, exhibit moderate performance with coefficients of performance (COP) ranging from 0.3 to 0.5 and specific cooling power (SCP) between 100 and 350 W kg−1. Substantial improvements have been achieved through the development of advanced materials such as CaCl2/silica gel composites, which demonstrate enhanced adsorption capacities (0.75 kg kg−1) and COP values approaching 0.8. Similarly, expanded graphite-based adsorbents significantly improve heat transfer properties, resulting in SCP values exceeding 1000 W kg−1. Metal–Organic Frameworks (MOFs) further enhance system performance, offering 10–20
This study experimentally investigates the combined effects of enamel coating thickness and shelf geometry on the thermal performance and energy efficiency of domestic electric ovens. Four configurations were tested by varying enamel thickness and shelf design. All four configurations operate in the transition natural convection regime. Dimensionless analysis showed comparable Nusselt numbers between the wire-rack and embossed-rack geometries, indicating that internal convective heat transfer alone does not explain the superior energy class achieved by the embossed-rack configuration. Thermographic and thermocouple measurements instead show that geometric irregularities in the embossed surface promote localized heat accumulation, reducing heat loss to the exterior at the cost of less uniform internal temperature distribution. The enamel layer dominates the composite wall resistance, accounting for up to 93.5
Proper forecasting of conductor temperature and ampacity within an underground cable network is crucial for safe operation and for proper network capacity analysis. A finite element (FE) thermal solver ensures high-fidelity answers. Nevertheless, when uncertainty in soil thermal resistivity, ambient temperature, loading, burial geometry, and sheath losses must be propagated through the model, the use of FE becomes impractical. Most existing soft-computing surrogates have been proposed as individual replacements, but few have been examined under the same uncertainty-quantification (UQ) microscope. This paper proposes a framework in which an FE truth model is combined with three surrogate families: an Adaptive Neuro-Fuzzy Inference System (ANFIS); a Bayesian deep neural network (Bayesian DNN) with Monte Carlo Dropout and heteroscedastic loss; and a probabilistic fuzzy ensemble with α-cut Monte Carlo propagation. Identical datasets are used to train and evaluate all three. Latin Hypercube Sampling is used to create 5000 FE designs of a 132 kV trefoil cable circuit. Models are assessed based on point-prediction error, predictive interval calibration, robustness to input noise, and inference cost. The Bayesian DNN obtains the highest R^2 (0.994), the lowest RMSE (0.94 °C), and well-calibrated 95
This study systematically examines the effects of nano-calcium carbonate (nano-CaCO3) on the heat release characteristics, mechanical properties, microstructure, and reaction mechanism of cement hydration through hydration heat tests, compressive strength tests, scanning electron microscopy (SEM), transmission electron microscopy (TEM), and thermokinetic modeling. With nano-CaCO3, the hydration heat peaks have an earlier onset, heat is released at a higher rate and a greater amount, and the early strength is increased. According to SEM analysis, nano-CaCO3 improves the cement microstructure. The Krstulovic–Dabic model confirms that nano-CaCO3 accelerates the hydration of Portland cement by promoting the nucleation and growth of hydration products and reducing the diffusion resistance.
Groove facades are extensively used in modern buildings because of their superior energy utilization efficiency and better natural lighting. To investigate the fire spatial characteristics of the groove facades, this paper analyzes the fire spread behavior and danger area distribution under lateral ambient wind. The results show that lateral wind shifts the smoke and elevated temperature regions from the central area of the external facade to the near-wind facade and then further to the groove front opening. The heat flow and smoke particle spillage increase significantly with rising wind velocity. The bottom attachment height on the near-wind lateral facade decreases from 9.3 to 7.1 m as the lateral ambient wind velocity increases from 2 to 10 m s−1. The maximum temperature position moves from 8.05 to 8.65 m on the X-axis and shifts from 3.7 to 4.9 m on the Y-axis. The lateral elevated temperature area reaches a peak of 16.1 m2 at a wind velocity of 2 m s−1 and remains at 8.8 m2 at a wind velocity of 10 m s−1, while the external elevated temperature area decreases from 13.5 to 2.8 m2. These findings indicate that the lateral ambient wind induces the near-wind migration, front-opening spillover, and danger area redistribution in the groove facade fires.
In this study, propylene glycol-cored silane-functionalized polyurethane acrylate (SiFPU) hybrid networks were synthesized via a three-step route combining prepolymer synthesis and thiol–ene photoclick chemistry to yield a semi-interpenetrating polymer network (semi-IPN) architecture. The research examined how the structure and concentration (26 mass
Thermochemical heat storage (TCHS) has emerged as one of the most promising long-term heat-energy storage technologies due to its high theoretical energy density and negligible heat loss during storage, making it compatible with renewable energy sources. Among sorption-based TCHS materials, salt hydrates with water vapor as the adsorbate pair are widely used due to their high hydration energy, availability, and low cost, and they require no intermediate or complicated synthesis methods. However, in practice, they remain inappropriate due to slow hydration kinetics, agglomeration, poor thermal conductivity, and structural instability during cyclic operation. Recently, many advanced TCHS matrices have been developed to address these limitations. The super-ultra-high and tunable porosity of Metal–Organic Frameworks (MOFs) and the thermally conductive 2D delaminates of MXenes provide a substantial opportunity to overcome the limitations of hydrate salts in terms of potential energy density. MOFs exhibit strong adsorption affinity through highly tunable pore architectures, whereas MXenes provide rapid heat-transport pathways and hydrophilicity through functional units like –OH, –O, etc. This mini-review provided a comprehensive overview of the synergistic effects of the MOF/MXene hybrid matrix, highlighting the combined effects of both constituents on enhanced heat storage capacity, reaction kinetics, and heat transport, as well as major practical limitations toward industrial-level application.
This study examines the local thermal response and post-fire flexural behaviour of welded austenitic stainless-steel beams with and without circular web openings. Four principal EN 1.4301 (AISI 304) specimens represented solid and cellular configurations tested at ambient condition and after a 30 min anisothermal furnace exposure. Type-J thermocouples at the mid-length of the web recorded final local steel temperatures of 631 °C for the solid beam and 652 °C for the cellular beam, compared with a calculated ISO 834 nominal gas-temperature target of approximately 842 °C at 30 min. Three-point bending was subsequently performed over a verified 900 mm clear span. The solid beam exhibited a 6.4
Endothermic high-energy nanofluid fuels represent a novel fuel type with great potential to address the overheating and thrust deficiency issues of scramjet engines under high Mach number. Boron features a high combustion calorific value, yet its lack of catalytic cracking activity renders it difficult to be directly used as an additive for endothermic nanofluid fuels. Herein, we first report a strategy of confined molecular phase change and boron nanoparticles catalysis for nanofluid stability and enhancement of physical and chemical heat sink. Boron nanoparticles with catalytic activity (NBK, nano-boron KH550) are obtained through ultrasound-assisted in situ surface functionalization treatment. The oxidation degree and calorific value of NBK were enhanced by 3.6
