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First-principles molecular dynamics combined with the approach-to-equilibrium molecular dynamics methodology is employed to calculate the thermal conductivity of non-stoichiometric amorphous SiN. This is achieved by implementing thermal transients in five distinct models of different sizes along the direction of the heat transport. Such models have identical structural features and are representative of the same material, thereby allowing for a reliable analysis of thermal conductivity trends as a function of the relevant cell dimension. In line with the known physical law of heat propagation at short scale, the thermal conductivity increases in size with the direction of heat transport. The observed behavior is rationalized accounting for previous results on crystalline and amorphous materials, thus providing a unified description holding for a large class of materials and spanning a wide range of heat propagation lengths. [ABSTRACT FROM AUTHOR]

We have successfully grown single crystals of layered mixed-anion compound Sr 2 ZnCu 2 Se 2 O 2 by a simple melt-growth method. Single crystals of the layered oxychalcogenides Sr 2 ZnCu 2 Se 2 O 2 were grown by melt-solidification of stoichiometric raw materials. Plate-like single crystals were obtained, and the maximum size of crystals was 2.5 × 1.4 mm2. Thermal analysis result indicates simple melting-solidification-like behavior, and the size of crystals increases significantly above the melting point revealed by this measurement. X-ray rocking curve (XRC) measurement results of the single crystal showed no peak splitting, with a narrow full width half maximum of 30 and 97 arcsec in (105) and (00 12) peaks, respectively. The electrical conductivity of single crystals on the a (b) plane was 4.34 × 10−1 S/cm at room temperature. Obtained single crystals were transparent, and the absorption edge was observed around 560 nm in the transmittance measurement. Although layered oxychalcogenide Sr 2 ZnCu 2 Se 2 O 2 has a complex composition and structure, this compound exhibits congruent melting behavior in a sealed environment. This feature enables us to grow single crystals of mixed-anion compounds easily by the melt-growth method. [ABSTRACT FROM AUTHOR]

The study is accomplished to explore the pioneering of a two-dimensional ferromagnetic fluid flow over a flat elastic sheet with the magnetic dipole effect. The recent flow design was selected as it is mostly applicable in bioengineering as well as engineering fields that includes magnetic drug targeting systems. In this paper, the impacts of thermal radiation and magnetic dipole in flow of ferromagnetic Sutterby fluid for a stretching surface are examined. Some suitable similarity transformations are exploited to achieve the system of nonlinear ODEs from set of PDEs, then acquired ODEs are resolved by numerical scheme known as bvp4c technique. Impacts of ferromagnetic interaction parameter, viscous dissipation and curie temperature are perceived for velocity as well as temperature fields. Furthermore, velocity as well as thermal gradients are deliberated and scrutinized pictorially. [ABSTRACT FROM AUTHOR]

The steam condenser is a crucial component in power plants, playing a vital role in influencing the overall performance of steam power plants. This paper delves into a detailed assessment of the thermal aspects and evaluation of steam surface condensers. To conduct this rigorous evaluation, we meticulously crafted a three-dimensional (3D) model of a multi-tube single-pass counter-flow heat exchanger using ANSYS Design-Modeller. Within this model, a multiphase mixture model was harnessed to replicate the condensation process that takes place within the condenser. After the model's development, a series of computational fluid dynamics (CFD) simulations were expertly executed utilizing ANSYS Fluent Workbench. The simulations encompassed diverse cooling water flow rates and steam inlet velocities. Notably, two sets of CFD simulations were carried out: the initial set featured a velocity inlet in the condenser, while the second set involved CFD simulations with a pressure steam inlet. The findings derived from these simulations unveiled a noteworthy correlation between the condensation rate within the shell and both the rate of circulating water flow and the operational pressure of the condenser. Additionally, it was discerned that the condensation rate could be further influenced by the specific geometry of the condenser. In sum, this study concludes that optimizing the geometrical configuration and baffle arrangements holds promise for increasing the condensation rate and overall performance of steam condensers employed within steam power plants. [ABSTRACT FROM AUTHOR]

The main purpose of this work is to investigate the innovation of flow of two-dimensional (2D) ferrofluid flow passing upon stretched surface having the effect of a magnetic dipole. The said problem is selected since its use is very common in biomedical as well as engineering applications together with systems of drug targeting under magnetic effects. The impacts of magnetic dipole along with radiation parameter in flow of ferromagnetic cross fluid for a stretched region are investigated in detail by use of suitable similarity variables the nonlinear, ODEs are obtained. The desired ODEs are resolved numerically by using RK fifth-order method parallel to shooting scheme. Impacts of ferromagnetic interaction, viscous dissipation, Curie temperature, and Buongiorno parameters with convective boundary conditions are perceived for velocity, temperature and concentration fields. Furthermore, the terms like velocity, mass transfer and thermal gradients are under consideration and pictorial scrutinizing is done. Moreover, temperature of ferromagnetic fluid upsurges for enlargement in the values of ferrohydrodynamics interaction and Curie temperature parameters. Concentration of ferrofluid reveals a contrary tendency against the parameters of thermophoresis and Brownian motion. Owing to extensive application prospects of magnetized nanofluids, this area has received interest from engineers and researchers; nanofluids have a noteworthy preference over ordinary fluids. [ABSTRACT FROM AUTHOR]

Thermal history sensors are valuable tools for thermal analysis of high-temperature components within aero-engines and gas turbines. However, most thermal history sensors have an upper temperature limit of ∼1200 °C, which is insufficient to meet the requirement of gas turbines. This study introduces a novel material for thermal history sensing capable of measuring temperatures up to 1400 °C. We show thermal history measurements based on the emission intensity ratio of a Eu3+-doped yttrium–aluminum mixture, whose luminescence characteristics undergo irreversible changes when exposed to high temperature. The primary mechanism is the decrease of the symmetry ratio owing to the phase transformation from YAG (Y 3 Al 5 O 12), YAM (Y 4 Al 2 O 9) to YAP (YAlO 3) utilizing the combination reaction of YAP induced by heat-treatment. The intensity ratio between 5D 0 →7F 1 and 5D 0 →7F 2 exhibits a monotonic decrease from 1.3 to 0.4 as the heat-treatment temperature increases from 1000 °C to 1400 °C. Moreover, we demonstrate that the irreversible change in intensity ratio after heat treatment remains insensitive to exposure time and oxygen partial pressure. Thus, the Eu3+-doped yttrium-aluminum mixture is a promising material for manufacturing high-temperature thermal history sensors. [ABSTRACT FROM AUTHOR]

Hydrogen has emerged as a promising clean energy carrier for automobile applications. Magnesium hydride (MgH2) has garnered significant attention as a potential H2 storage material due to its high capacity and low cost. Nonetheless, its practical use is hindered by unfavorable H2 sorption kinetics and operating temperatures. This study presents a novel approach to enhance the H2 storage properties of MgH2 by adding graphene oxide (GO) supported tin dioxide (cSnO2) nanoparticles. The as-prepared catalysts (GO/SnO2) were synthesized through modified chemical methods followed by ball-milling with MgH2 characterized using various techniques, including X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray and Fourier transform infrared spectroscopy (FTIR). The catalytic effect of GO-SnO2 nanoparticles on MgH2 was investigated through systematic H2 sorption studies as well as thermal analysis. Results demonstrate that the onset temperature for H2 desorption was significantly reduced, and the dehydrogenation kinetics were substantially enhanced. [ABSTRACT FROM AUTHOR]

Compared to helically coiled tube exchangers (HCTs), longitudinally curved tube exchangers (LCTs) have received little attention from scientists over the past decade, leading to a lack of correlations estimating the Nusselt number and friction factor. In view of recent studies promoting the use of LCTs (waved, C-shaped or sinusoidal) in linear solar concentrating systems, this study examines whether or not correlations of and developed explicitly for HCTs could be applied to LCTs. A (SST) turbulent model has been run on HCTs and validated by experimental correlations from the literature. With an amplitude ratio equal to unity (waviness amplitude to the curvature radius ratio) and the same curvature ratio (tube radius to the curvature radius ratio), LCTs and HCTs are geometrically similar. For these similar configurations, the numerical results of over the Reynolds number range overlap almost perfectly, which is not for. Over the LTC amplitude ratio range, no significant change in the mean was reported, with a max relative error of 3.98%, whereas was highly dependent on it. One key finding: with a similar curvature ratio, correlations of the mean developed previously for HCTs could be used for LCTs, which is not valid for the mean. [ABSTRACT FROM AUTHOR]

In recent years, researchers and scholars have shown growing interest in exploring the applications of natural fibers in polymer composites, driven by their environmentally friendly and sustainable characteristics. This study endeavors to offer an exhaustive examination of the prominent and widely adopted natural fiber reinforced polymer composites and their diverse range of applications. Furthermore, it provides an overview of different surface treatment methods applied to natural fibers and their influence on the properties of, highlighting the significant variations in properties depending on the fiber type, source, and structure. Bamboo fibers (BF) and recycled chemically functionalized acrylonitrile-butadiene-styrene (r-ABS) composites (BF/rABS) have been blended at 190°C. The composites show a higher tensile and flexural properties than r-ABS. The presence of bamboo fibers functions as stress concentrators, resulting in minimized deformation and consequently reducing the impact strength of the composites in comparison to the matrix. The SEM and FTIR analysis have shown that the adhesion between fiber and the matrix is good which therefore improves the tensile properties of the composite materials. XRD analysis has shown improved crystallinity in composite as compared to matrix. [ABSTRACT FROM AUTHOR]

Polyvinyl alcohol (PVA) is a highly flammable material, and enhancing its flame retardancy to pass the glow wire test is a great challenge. In this work, the melamine salt of tannic phosphate (MTP) was synthesized, characterized, and combined with PVA at 8, 10, 13, and 15 wt%. The thermogravimetric analysis (TGA) results indicated that MTP enhanced the char formation of PVA at 750°C. Flammability tests showed that low concentrations of MTP can enhance the flame retardancy of PVA. The limiting oxygen index (LOI) of PVA increased from 18.8% to 39.9% in the PVA/15%MTP composite. The vertical flame spread test (UL94V) showed that PVA/13%MTP, and PVA/15%MTP composites achieved V0 rating. Glow wire test data indicated that PVA/10%MTP, PVA/13%MTP, and PVA/15%MTP composites had a glow wire flammability index (GWFI) of 960°C/2 mm. Moreover, all the composites passed the needle flame test when the flame application time was 120 s. PVA/15%MTP composite showed very good UV protection and an increase in sound absorption coefficient magnitude compared with pure PVA. The new results can increase the application of PVA in different industries. [ABSTRACT FROM AUTHOR]

This paper presents a new method for the layered equivalent modeling of slot winding in the stator of a flat wire motor to accurately study the thermal performance under steady-state conditions. The conventional equivalent model for flat wire winding involves treating the slot winding as a single copper rod for temperature analysis. This method is not applicable to flat wire motors under high-power density operating conditions. As the power density of the motor increases, the flat wire winding is more affected by skin effect and proximity effect, resulting in a sharp increase in AC loss and uneven distribution of losses in the slot winding. The conductor losses are highest near the slot opening, a characteristic that conventional model is unable to reflect. The proposed layered modeling method fully takes into account the characteristics of flat wire winding. This method involves adding interlayer insulation to divide the overall modeled conductor into layers and fully considers the thermal parameters, heat transfer characteristics, and distribution of materials within the slot to establish a new equivalent model for flat wire winding. Finally, the comparison of the results with the actual model and experimental tests demonstrates that this method effectively improves the calculation accuracy by 2.2% of the flat wire winding equivalent model. [ABSTRACT FROM AUTHOR]

Summary: In frozen part‐baked bread technology, starch is influenced by various processing factors. This study aimed to investigate the effect of part‐baking time, freezing rate and frozen storage time on pasting, thermal and structural properties of part‐baked bread. Wheat dough was part‐baked for 0, 3 or 6 min and frozen at −20 °C using two freezing rates: slow (0.15 °C min−1) or fast (1.45 °C min−1). Next, samples were stored in frozen conditions for 56 days and analysed every 14 days for starch damage, pasting properties, thermal and X‐ray analysis. The level of damaged starch increased with 3 min (69.3%), and 6 min (88.8%) of part‐baking time for both freezing rates compared to no part‐baked. In pasting analyses, peak viscosity decreased 27.3% and 38.4% for 3 and 6 min of part‐baking time, respectively, at 0 days of frozen storage; however, this tendency was observed for all frozen storage time. The gelatinisation enthalpy (ΔHg) decreased as part‐baking time increased, showing the maximum reduction at 6 min of part‐baked (94.9%). In X‐ray diffraction analyses at 3 and 6 min of part‐baking, the intensity of the signal increased 4.4% and 10.9%, respectively, probably due to the starch gelatinisation. These results can serve as a valuable guide for developing strategies to enhance the quality of part‐baked bread and improve production performance. [ABSTRACT FROM AUTHOR]

This comprehensive research addresses the significant challenge of building‐related energy consumption in Morocco. Our innovative approach involves integrating phase change materials (PCMs) into hollow bricks, strategically addressing the diverse climate zones prevalent in the country. The primary focus is on enhancing energy efficiency within structures. Leveraging detailed simulations and employing the enthalpy‐porosity approach, our study models the impact of PCMs on internal temperatures. Optimal outcomes are achieved by partially filling brick holes with PCMs in specific configurations, demonstrating the materials' ability to adapt to varying conditions. A noteworthy finding is the 2–3‐h phase shift observed in cold zones, indicating the potential for PCMs to effectively regulate temperatures. Equally significant is their capability to maintain a constant internal temperature of 26°C in hot zones, even amidst extreme external conditions reaching up to 47°C. This resilience underscores the novel and tailored thermal regulation potential of PCMs. Beyond the technical insights, our research highlights the paramount importance of considering regional climates in PCM applications' implementation. This awareness is crucial for optimizing energy performance in buildings and ensuring sustainability. In essence, this study contributes valuable knowledge and practical implications for the strategic deployment of PCMs to enhance building energy efficiency, emphasizing the need for context‐specific solutions in diverse environmental conditions. [ABSTRACT FROM AUTHOR]

Modeling a combination of thermal radiation and conjugate heat transfer in a three‐dimensional rectangular domain which has a participating media CO2 flowing through is done numerically in OpenFOAM. The rectangular duct has a vertical step (facing forward to the inlet) which is located at a distance from the inlet (the distance is same as the height of the inlet section). The domain is divided into two regions (namely solid and fluid). Carbon dioxide, a highly absorbing fluid with extinction, is used here as the participating medium. The ability of the code is verified to analyze the thermal radiation in a participating media with conjugate heat transfer. The study was carried out for a constant Reynolds number 250 and a contraction ratio of 0.5. The study focused primarily on the importance of adding thermal radiation on to thermal analysis and the reason behind the Nusselt number variation on different regions of solid–fluid interface. It also discussed the effect of radiative properties, such as optical thickness and linear scattering albedo, on the average convective Nusselt Number. [ABSTRACT FROM AUTHOR]

• The study reveals that heat conduction model is sufficient to describe melt pool size in SLS of polymer. • The hybrid PINN and FEM model can parametrically and rapidly simulate temperature profiles and melt region morphologies. • Results demonstrate high fidelity in both temperature levels and final melt region compared to pure FEM models. • The hybrid model effectively addresses process parameter selection in real-world production scenarios. The state of the melt region as well as the temperature field are critical indicators reflecting the stability of the process and subsequent product quality in selective laser sintering (SLS). The present study compares various simulation models for analyzing melt pool morphologies, specifically considering their complex transient evolution. While thermal fluid dynamic simulations offer comprehensive insights into melt regions, their inherent high computational time demand is a drawback. In SLS, the polymer's high viscosity and low conductivity limit liquid flow, thereby promoting a slow evolution of the melt region formation. Based on this observation, utilizing low-complexity pure heat conduction simulation can be adequate for describing melt region morphologies as compared to the more complex thermal fluid dynamic simulations. In the present work, we propose such a purely conduction based finite element (FE) model and use it in combination with an AI-powered partial differential equation (PDE) solver based on a parametric physics-informed neural network (PINN). We specifically conduct the simulations for the sintering process, where large thermal gradients are present, with the parametric PINN based model, whereas we employ the finite element method (FEM) for the cooling phase in which gradients and cooling rates are several orders lower, thus enabling the prediction of sintering temperature and melt region morphology under various configurations. The combined hybrid model demonstrates less than 7% deviation in temperatures and less than 1% in melt pool sizes as compared to the pure FEM-based models, with faster computational times of 0.7 s for sintering and 20 min for cooling. Moreover, the hybrid model is utilized for multi-track simulation with parametric variations with the purpose of optimizing the manufacturing process. Our model provides an approach to determine the most suitable combinations of settings that enhance manufacturing speed while preventing issues such as lack of fusion and material degradation. [ABSTRACT FROM AUTHOR]

• Heat conduction in perforated laminated plate by elliptical holes is solved using formulated special elements. • Special fundamental solutions are derived using Stroh formula and conformal mapping. • Special element containing a rotated elliptical hole is formulated in the concept of hybrid finite element. • Meshing effort around hole region is greatly alleviated and element boundary integration is featured. • The accuracy, efficiency and flexibility of the present special element are demonstrated. The high-efficient and accurate analysis of anisotropic composite media weakened by a large amount of holes or cuts is still a great challenge in practical composite engineering. In this work, specially-proposed polygonal finite element enclosing an arbitrarily oriented elliptical hole in general anisotropic composite media is formulated for thermal analysis in the framework of hybrid finite element theory. Two independent temperature field approximations are defined for the present special element: Intra-element temperature field and element frame temperature field. The former defined inside the element is written in the form of truncated summation of the weighted special fundamental solutions, which are derived using the Stroh complex theory and conformal mapping whilst the latter is implemented by the conventional shape function interpolation. Then the hybrid variational functional is employed to combine them together to generate an element stiffness equation with respect to nodal temperature and an optional relationship between the interpolation coefficients. The element stiffness matrix is symmetric and involves element boundary integrals only. Compared to the traditional finite element, the distinctive element-boundary-integral and enclosed-elliptical-hole features make the present element significantly improve the meshing effort around an elliptical hole by reducing the number of elements and decreasing the meshing difficulty, and more importantly, effectively capture the critical variation of physical fields around the elliptical hole without locally-refined meshes. Moreover, the present special element can be incorporated directly into the conventional finite element system without any difficulty for extensive analysis. Finally, several typical examples are simulated by the present special elements to demonstrate their effectiveness. [ABSTRACT FROM AUTHOR]

• A model to explore the multiphysics characteristic of semiconductors is presented. • The model determines the thermal and mechanical properties of complex patterns. • Results show a strong correlation between thermal and mechanical properties. • Dielectric bands asymmetrically affect thermal and mechanical behavior. • Machine learning can predict one property from another. As semiconductor performance improves through advanced package designs, it becomes important to consider both thermal and mechanical properties. Better understanding their relationship enhances system design and optimization. This study has introduced a numerical method that takes into account both thermal and mechanical fluxes to construct thermal and mechanical property maps for practical application in semiconductor engineering. Furthermore, this paper investigated the relationship between the two properties using the constructed property maps in commercially available semiconductor packages. Owing to the complexity of packaging design patterns, a coupled isoparametric mapping and machine learning (ML) method was introduced to investigate their effects. The model then determines and investigates the anisotropic equivalent thermal and mechanical properties of the commercialized semiconductor packages with complex pattern designs, according to the package materials, volume fractions of each material, and design patterns. This approach pursues more sophistication and practicality compared to simplified composite structure property evaluation models. Additionally, all processes in the algorithm are automated based on ML methods, making them practically applicable in the semiconductor industry. The study shows that there is a strong correlation between the thermal and mechanical characteristics in the complex package patterns. This relationship was able to form a fairly clear category based on the shape of the dielectric band because the dielectric band had significantly different effects on the thermal and mechanical fluxes. The study discussed the physical implications of the similarities and differences between the two behaviors and validated the results of the equivalent properties through finite element (FE) analysis. Finally, the study cross-validates the relationship by showing that information from one flux behavior can be used to predict the other based on the ML method. Based on the results, this paper can provide a better understanding of thermal and mechanical fluxes in semiconductor package patterns for package design and optimization. [ABSTRACT FROM AUTHOR]

When analyzing materials non-isothermally using the Arrhenius equation under linear heating, a temperature integration is necessary. While the frequency factor in this equation is typically assumed to be constant, it can actually vary with temperature for certain solid-state reactions. The resulting temperature integral, known as the Arrhenius or general temperature integrals, usually have no analytical solutions. Therefore, special functions and approximation functions are often used to estimate them. In this particular study, new rational approximations for the Arrhenius and general temperature integrals were derived through the expansion of the incomplete gamma function. Two sets of these rational approximations, which exhibit excellent accuracy, are presented. One set of approximations for the Arrhenius integral matches the widely used Senum and Yang's approximations, while the other set, which offers even greater accuracy, has not been previously reported. An obtained rational approximation has been utilized to simulate the thermal degradation of a commercially available PMMA, illustrating a practical application example. [ABSTRACT FROM AUTHOR]

The semi-organic nonlinear optical single crystal Bis (L-Tyrosinato) Cupric acetate (BLTC) was synthesized through a slow evaporation process in atmospheric conditions. A single crystal X-ray diffraction analysis of the formed crystal revealed that it is an orthorhombic crystal system with the space group P212121. Additionally, the powder X-ray diffraction patterns and diffracting planes of the BLTC crystal were recorded and identified. Fourier Transform Infrared (FTIR) spectroscopy analysis was used to characterize the formed crystals in order to identify the various vibrational modes caused by the different functional groups present in BLTC. The 1H and 13C NMR spectra were used to examine the crystal's hydrogen and carbon environments. The UV-visible, near-infrared, and photoluminescence (PL) analyses have been used to do optical studies. According to our findings, the material has a decreased cut-off wavelength and a high transparency window, making it suitable for nonlinear optical (NLO) and optoelectronic applications. The BLTC crystal's predicted band gap was found to be 4.1 eV. Thermo gravimetric (TG) and differential thermal analysis (DTA) techniques were used to determine the thermal properties of BLTC. With three different frequencies, the dielectric measurement of the crystal was observed with respect to temperature. An analysis has been done on the harvested crystals mechanical characteristics. In the developed BLTC crystal, morphological changes on the surface are seen. The material's second harmonic generation (SHG) was tested using the Kurtz and Perry powder method, and it was found to be higher than the KDP. [ABSTRACT FROM AUTHOR]

Diurnal and seasonal temperature variations cause uniform temperature changes, vertical temperature gradients, and horizontal temperature gradients. Vertical temperature gradients occur when the bridge deck absorbs heat due to solar radiation more than the bottom parts of bridge girders. Consequently, the vertical temperature gradient causes redistribution of bearing reactions, and induces additional flexural stresses in continuous spans. Estimating the vertical temperature gradient effect on continuous concrete bridges requires knowledge of thermal analysis of statically indeterminate structures or advanced three-dimensional (3 D) finite element (FE) analysis. Therefore, this article focuses on developing a simplified analysis method for estimating vertical temperature variations effects on continuous prestressed concrete bridge girders, which is required for bridge design. Restraint moments induced by vertical temperature gradients are investigated using 3 D FE analysis. A total of 115 bridges with different configurations (number of spans, girder spacing, and girder type) were analyzed to estimate the positive thermal moments at support locations. Results from these analyses were then used to develop simplified equations for estimating the positive restraint moments due to vertical temperature gradients from AASHTO LRFD Bridge Design Specifications (BDS). The developed equations are validated using John James Audubon Bridge #2 field data, and for other AASHTO LRFD temperature zones. [ABSTRACT FROM AUTHOR]

One of the effective ways to achieve drilling of Carbon fiber reinforced polymer (CFRP) materials is to use short pulse lasers. However, the existing cutting thermal damage, such as the heat-affected zone (HAZ), can weaken the CFRP mechanical properties. In this paper, a heterogeneous mesoscopic model of transient distribution of short pulse laser ablation heat flow is built to fully explore the formation and extension mechanism of thermal damage. The significant difference in laser interaction thermal effects between fibers and resin leads to the formation of HAZ with exposed fibers. The interface effect exists in the ablation process, which aggravates the matrix damage. The ablation of carbon fibers occurs within the duration of a single laser pulse, and the degree of ablation depends on the pulse energy. Under the coupling of the thermal conduction effect along the fiber axis and the thermal accumulation effect between pulses, the matrix damage extends significantly during the cooling stage. Large pulse repetition frequency increases heat accumulation between pulses and increases matrix damage. There is a new erosion mechanism in that the thermal accumulation behavior leads to the falling off of fragmented carbon fiber filaments. The accuracy of the model was verified through different pulse ablation tests, and the average error of ablation morphology is 11.28%. [ABSTRACT FROM AUTHOR]

The lie-detection tests are traditionally carried out by well-trained experts using polygraph machines. However, it is time-consuming, invasive, and, overall, a cumbersome process, not admissible by the court of law. Trained individuals can easily flaunt these tests. On the other hand, facial thermal imaging could be more effective as it is noninvasive and could be a stealth method of tracking the facial blood flow patterns, which have been proven to detect deceit. This paper presents a method based on facial thermal imaging to detect deception in human subjects. The major issue in such research is the lack of proper real-life databases which emulate the crime scenes. In this paper, first, we have developed a database based on almost real-life theft incidents with due diligence using isolated subjects over a period of time at a government hospital under the plea of free health checkup. The experiment has been conducted at Midnapore Medical College and Hospital, West Bengal, India, with proper ethical committee approval. The participants are selected at the behest of the police department with habitual crime records. Most of them have been repeatedly charged with petty crimes of pick-pocketing and stealing. They are invited individually at different instances of time under the plea of medical checkup where they have been enticed to steal cash. It is followed by a two-stage process, a friendly interaction followed by a slightly tougher interrogation. Their forehead and periorbital region skin surface temperature are recorded by a hidden thermal camera. Upon analysis, conspicuous changes in the temperature profile and blood flow pattern have been observed in the individuals who stole money and those who did not. [ABSTRACT FROM AUTHOR]

As the imbalance between power demand and load capacity in electrical systems becomes increasingly severe, investigating the temperature variations in transformers under different load stresses is crucial for ensuring their safe operation. The thermal analysis of converter transformers poses challenges due to the complexity of model construction. This paper develops a full-scale model of a converter transformer using a multi-core high-performance computer and explores its thermal state at 80%, 100%, and 120% loading ratios using the COUPLED iteration method. Additionally, to validate the simulation model, 24 FBGs are installed in the experimental transformer to record the temperature data. The results indicate a general upward trend in winding the temperature from bottom to top. However, an internal temperature rise followed by a decrease is observed within certain sections. Moreover, as the loading ratio increases, both the peak temperature and temperature differential of the transformer windings rise, reaching a peak temperature of 107.9 °C at a 120% loading ratio. The maximum discrepancy between the simulation and experimental results does not exceed 3.5%, providing effective guidance for the transformer design and operational maintenance. [ABSTRACT FROM AUTHOR]

We studied a gradient anti-oxidation coating of C/C composite materials for aircraft brake discs with a simple process and low costs. The gradient coating consists of two layers, of which the inner layer is prepared with tetraethyl orthosilicate (Si (OC2H5)4), C2H5OH, H3PO4 and B4C, and the outer layer is prepared with Na2B4O7.10H2O, B2O3, and SiO2 powder. The experimental results show that after being oxidized at 700 °C for 15 h, the oxidation weight loss of the sample with the coating was only −0.17%. At the same time, after 50 thermal cycles in air at 900 °C, the sample's oxidation weight loss was only −0.06%. We conducted the 1:1 dynamic simulation test for aircraft brake discs, and the brake disc did not oxidize, thus meeting the requirements for aircraft use. In addition, the anti-oxidation mechanism of the coating was analyzed via scanning electron microscopy (SEM), X-ray diffraction (XRD), differential thermal analysis (DSC-TGA), and high-temperature in situ SEM. [ABSTRACT FROM AUTHOR]

2,3-dihydro-5,6,7,8-tetranitro-1,4-benzodioxine (TNBD), molecular formula = C8H4N4O10, is a completely nitrated aromatic ring 1,4-benzodioxane derivative. The convenient method of TNBD synthesis was developed (yield = 81%). The detailed structure of this compound was investigated by X-ray crystallography. The results of the thermal analysis (TG) obtained with twice re-crystallized material revealed the onset at 240 °C (partial sublimation started) and melting at 286 °C. The investigated material degraded completely at 290–329 °C. The experimental density of 1.85 g/cm3 of TNBD was determined by X-ray crystallography. The spectral properties of TNBD (NMR, FT-IR and Raman) were explored. The detonation properties of TNBD calculated by the EXPLO 5 code were slightly superior in comparison to standard high-energy material—tetryl (detonation velocity of TNBD—7727 m/s; detonation pressure—278 kbar; and tetryl—7570 m/s and 226.4 kbar at 1.614 g/cm3, or 260 kbar at higher density at 1.71 g/cm3. The obtained preliminary results might suggest TNBD can be a potential thermostable high-energy and -density material (HEDM). [ABSTRACT FROM AUTHOR]

Considering the influence of thermal stress and material property variations, this study employs the Navier–Stokes equations and Fourier heat conduction law to establish a semi-implicit time-domain numerical analysis method for hypersonic aerothermal-structural coupling. Study the temporal variation pattern of different regions of the composite material wing under aerodynamic heating. Using the obtained transient temperature field of the wing, the thermal modal of the wing at different time points is calculated using the finite element method. Additionally, it conducts an analysis and discussion on the factors influencing the thermal modal. Composites can be effectively utilized as thermal protection materials for aircraft. During the aerodynamic heating process, the leading edge temperature reaches thermal equilibrium first, followed by the trailing edge, and the belly plate experiences a slower thermal response. Temperature rise significantly affects higher-order modes, with the change in material properties during the early stages of heating being the dominant factor. This leads to a faster decrease in natural frequency. As heat conduction progresses, the influencing factors of thermal stresses gradually increase, and the natural frequency decreases slowly or even rises. [ABSTRACT FROM AUTHOR]

Highlights Since acrylate‐based materials are widely used in dentistry, their drawbacks such as low impact resistance and hardness, require continuous research in the field of materials science in order to avoid sudden fracture caused by chewing or fall. In this study, auto‐polymerizing poly(methyl methacrylate) (PMMA), commonly used as denture base material, was reinforced with poly(4‐styrenesulfonic acid‐co‐maleic anhydride) sodium salt (PSSMA) and strontium titanate (STO), with the aim of improving impact behavior and microhardness. Morphological analysis confirmed formation of phase‐separated and co‐continuous microscopic structures of PSSMA in PMMA, without visible agglomerates of STO nanoparticles, indicating that PSSMA‐STO interaction contributed to a better distribution of nanoparticles. Fourier transformed infrared spectroscopy revealed that PSSMA and STO did not interfere in the polymerization of methyl methacrylate. This was further supported by thermal analysis, which also showed that the addition of PSSMA and STO had no significant influence on thermal degradation. On the other side, PSSMA and STO significantly enhanced mechanical performance of PMMA. The modulus of elasticity increased by up to 48.6%, total absorbed impact energy improved by up to 108.4%, and microhardness increased by up to 272.8% when PSSMA was combined with STO for reinforcing denture PMMA. These results demonstrate the significant potential of PSSMA, which could be combined with other ceramic nanoparticles for denture reinforcement in the future. This research presents novel dental hybrid composite. Influence of strontium titanate (STO) and poly(4‐styrenesulfonic acid‐co‐maleic anhydride) sodium salt (PSSMA) on poly(methyl methacrylate) (PMMA) was investigated. PSSMA/STO improved modulus of elasticity, microhardness and impact resistance. Sample with 5 wt% PSSMA and 1 wt% STO showed the highest improvement compared to PMMA. Presented hybrid composite could use as denture base material. [ABSTRACT FROM AUTHOR]

The thermal error in the spindle unit is substantial and necessitates mitigation. Current models, being predominantly static in nature, have limited efficacy in error control. Integrating digital twin technology for modeling and controlling spindle unit thermal error holds promise in enhancing the machining accuracy of machine tools. Yet, the notion of a digital twin system specifically tailored for spindle unit thermal characteristics remains uncharted territory. To navigate these challenges, this study introduces a novel digital twin system tailored for spindle unit thermal characteristics. This system is poised to revolutionize thermal error modeling and compensation by harnessing the capabilities of digital twin technology. Within this digital twin framework, both the thermal error control model and the analytical thermal characteristic model are seamlessly integrated. The control model is devised as an exponential function, utilizing operational time, inherent time constants, and both initial and equilibrium thermal errors as parameters. Delving deeper, the analytical thermal characteristic model for the spindle system is rooted in a thermal resistance network approach. This leads to a closed-loop thermal characteristic modeling process, culminating in the derivation of a steady-state thermal error. Intricate heat transfer dynamics between spindle components are dissected, and a comprehensive thermal equilibrium equation set is formulated for the spindle unit. This equation set comprehensively accounts for dynamic variations in key parameters such as preload, lubricant viscosity, thermal load intensity, thermal contact resistance, and convective coefficients. To ascertain the time constant, a meticulously designed set of thermal characteristic experiments is executed. Subsequently, the digital twin system embarks on predictive modeling of thermal errors across varied operational conditions. This prediction then forms the foundation for thermal error compensation. With the integration of the present model into the digital twin system, the results are impressive: the absolute average and maximum deviations in thermal elongation, post-error control, stand at approximately 0.40 μm and 1.24 μm, respectively. [ABSTRACT FROM AUTHOR]

In this work, a novel series of borophosphate glasses of the system 40B 2 O 3 –25P 2 O 5 –(20-x)Na 2 O–15CaF 2 –xMgO (x = 0, 2.5, 5, 7.5, and 10 mol%) were synthesized using the melt-quenching technique. The effect of replacing Na 2 O with MgO in the glasses was analyzed by the physical and bioactive properties. The glasses were characterized by density, molar volume, X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), Differential thermal analysis (DTA), bioactivity tests in simulated body fluid (SBF), pH measurements, mass loss, and verification of cellular compatibility in RAW 247 murine macrophages. XRD and FTIR analyses were performed before and after immersion in SBF to verify the bioactivity. Density, molar volume and FTIR results before SBF showed structural changes in the glasses due to the addition of MgO. The pH and mass loss measurements allowed to verify the degradation behavior of the glass series as a function of MgO concentration. The DTA data showed an increase in T g , T x, and thermal stability due to the increase in MgO addition. XRD and FTIR analyses after SBF soaking showed superficial formation of apatites and other calcium phosphates of biological interest in the samples, attesting the bioactivity. Cytotoxicity assessed by MTT assay on the cell line RAW 247 showed that at a concentration of 500 μg/mL all glasses were compatible (non-cytotoxic). The results suggest that the synthesized glasses are bioactive, with the sample containing 5 mol% MgO exhibiting the bioactivity and biocompatibility required for biomaterial applications. [ABSTRACT FROM AUTHOR]

People spend majority of their lifetime indoors making comfortable dwellings one of the major requirements otherwise it may primarily impact the occupant's health and productivity. Indoor temperature and relative humidity (RH) are the two major parameters for determining comfort level, whilst airflow and heat transfer are having an influential role in controlling these parameters. Since solar radiations are the primary source of heat inside a building and ceiling fans play a significant role in improving air circulation. The present study strives to develop a model for evaluating the thermal behavior of commercial space under the influence of solar radiations and ceiling fans. It involves "solar ray tracing" and "3D-Fan zone" models to assess their impact on indoor air quality and thermal comfort. The developed model is validated by comparing the simulated results of air velocity and temperature with experimental data accumulated from space. Further, the validated model is used to evaluate the impact of different levels of solar irradiation between 200 W/m2 and 1000 W/m2 on the indoor environment. Results revealed that an increment of 200 W/m2 irradiations is raising the mean indoor temperature by 0.2 °C, percentage dissatisfaction by 8% while a reduction in RH is reported to be 0.5%. [ABSTRACT FROM AUTHOR]

The precipitation and deposition of asphaltenes are significant challenges in the petroleum industry resulting in substantial costs. A practical approach to addressing this issue is to use chemicals as inhabiting and dispersing agents. Zwitterionic surfactants are interesting materials in this field. In this study, three zwitterionic compounds including 2-(1-methyl-1H-imidazol-3-ium-3-yl)butane-1-sulfonate (MIBS), 4-(pyridin-1-ium-1-yl) butane-1-sulfonate (PBS), and 4-(tributylammonio)butane-1-sulfonate (TBBS) were synthesized and characterized by FT-IR, NMR spectroscopy, thermogravimetric, and differential thermal analysis. The ability of these zwitterions to prevent asphaltenes precipitation was investigated using interfacial measurements, ultraviolet spectroscopy, quartz microbalance analysis, particle size analysis, and optical microscopy. The results showed that the MIBS zwitterion, which contains an imidazole cation, was the most effective in dispersing asphaltene aggregates compared to the other two zwitterions. For instance, the UV spectroscopy results showed that the dispersion indexes for MIBS, PBS, and TBBS were 52.8%, 29.9%, and 16.3%, respectively. In addition, the size of asphaltene particles reached from 2179 nm to 622, 1489, and 2038 nm for MIBS, PBS, and TBBS, respectively. Finally, a comparison between the performance of these zwitterions with sodium dodecyl sulfonate (SDS) and tetrabutylammonium hydrogen sulfate (TBAHS) showed the following trend: MIBS (90.5%)> PBS (79.4%) > TBAHS (75%)> SDS (73.9%) >TBBS (46%). [ABSTRACT FROM AUTHOR]

GW501516, also known by the name of cardarine, is a synthetic peroxisome-proliferator-activated receptor delta (PPR-δ) agonist agent developed for applications in the treatment of metabolic disorders and cardiovascular diseases. A broad polymorph screening in various solvents and mixtures was completed in order to explore its capabilities to grow polymorphs. The crystal structures of four polymorphs were elucidated using single-crystal X-ray diffraction, while one structure was solved via a powder X-ray diffraction method. The solid state features (nature of intermolecular interactions) were investigated by computational methods. The polymorphs were further investigated by thermal DSC analysis and X-ray diffraction on powders. From a pharmaceutical perspective, the stability and solubility of the polymorphs were analyzed as well. [ABSTRACT FROM AUTHOR]

Naples is the most densely populated Italian city (7744 inhabitants per km2). It is located in a particular geological context: the presence of Mt Vesuvius characterizes the eastern part, and the western part is characterized by the presence of the Phlegrean Fields, making Naples a high-geothermal-gradient region. This endogenous heat, combined with the anthropogenic heat due to intense urbanization, has defined Naples as an ideal location for Surface Urban Heat Island (SUHI) analysis. SUHI analysis was effectuated by acquiring the Land Surface Temperature (LST) over Naples municipality by processing Landsat 8 (L8) Thermal Infrared Sensor (TIRS) images in the 2013–2023 time series by employing Google Earth Engine (GEE). In GEE, two different approaches have been followed to analyze thermal images, starting from the Statistical Mono Window (SMW) algorithm, which computes the LST based on the brightness temperature (Tb), the emissivity value, and the atmospheric correction coefficients. The first one is used for the LST retrieval from daytime images; here, the emissivity component is derived using, firstly, the Normalized Difference Vegetation Index (NDVI) and then the Vegetation Cover Method (VCM), defining the Land Surface Emissivity (LSɛ), which considers solar radiation as the main source of energy. The second approach is used for the LST retrieval from nighttime images, where the emissivity is directly estimated from the Advance Spaceborne Thermal Emission Radiometer database (ASTER-GED), as, during nighttime without solar radiation, the main source of energy is the energy emitted by the Earth's surface. From these two different algorithms, 123 usable daytime and nighttime LST images were downloaded from GEE and analyzed in Quantum GIS (QGIS). The results show that the SUHI is more concentrated in the eastern part, characterized by intense urbanization, as shown by the Corine Land Cover (CLC). At the same time, lower SUHI intensity is detected in the western part, defined by the Land Cover (LC) vegetated class. Also, in the analysis, we highlighted 40 spots (10 hotspots and 10 coldspots, both for daytime and nighttime collection) that present positive or negative temperature peaks for all the time series. Due to the huge amount of data, this work considered only the five representative spots that were most representative for SUHI analysis and determination of thermal anomalies in the urban environment. [ABSTRACT FROM AUTHOR]

A family of silver(I) and copper(I) complexes containing carboxylate ligands were prepared from the corresponding carboxylic acids and Ag2O. The compounds were characterized by various spectroscopic methods and X-ray diffraction. In the solid state, the silver(I) salts are coordination polymers based on dinuclear silver species with bridging carboxylate ligands. The reaction of these silver salts with Ph3P gives four-coordinate, tetrahedral bis(phosphine) complexes. Analogous copper(I) bis(phosphine) compounds were prepared by the reduction of copper(II) carboxylates with Ph3P. Decomposition temperatures and thermal decomposition products were studied by TGA/DSC measurements. The metal compounds decomposed cleanly to their respective metals (silver or copper) at temperatures ranging from 206 to 338 °C. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this study is to investigate the thermoforming process of 3D-printed parts made from polylactic acid (PLA) and explore its application in producing wrist-hand orthoses. These orthoses were 3D printed flat, heated and molded to fit the patient's hand. The advantages of such an approach include reduced production time and cost. Design/methodology/approach: The study used both experimental and numerical methods to analyze the thermoforming process of PLA parts. Thermal and mechanical characteristics were determined at different temperatures and infill densities. An equivalent material model that considers infill within a print is proposed. Its practical use was proven using a coupled finite-element analysis model. The simulation strategy enabled a comparative analysis of the thermoforming behavior of orthoses with two designs by considering the combined impact of natural convection cooling and imposed structural loads. Findings: The experimental results indicated that at 27°C and 35°C, the tensile specimens exhibited brittle failure irrespective of the infill density, whereas ductile behavior was observed at 45°C, 50°C and 55°C. The thermal conductivity of the material was found to be linearly related to the temperature of the specimen. Orthoses with circular open pockets required more time to complete the thermoforming process than those with hexagonal pockets. Hexagonal cutouts have a lower peak stress owing to the reduced reaction forces, resulting in a smoother thermoforming process. Originality/value: This study contributes to the existing literature by specifically focusing on the thermoforming process of 3D-printed parts made from PLA. Experimental tests were conducted to gather thermal and mechanical data on specimens with two infill densities, and a finite-element model was developed to address the thermoforming process. These findings were applied to a comparative analysis of 3D-printed thermoformed wrist-hand orthoses that included open pockets with different designs, demonstrating the practical implications of this study's outcomes. [ABSTRACT FROM AUTHOR]

The composition and structure of Sherobod quartz sand and man-made waste were fully investigated using chemical, scanning electron microscope, X-ray, infrared spectroscopic and differential thermal analysis methods. It was found that the content of lead and manganese oxides in Handiza lead concentrate and manganese waste is 25 - 26 %, respectively, and silicon oxide in Sherabad quartz sand is more than 80 %. According to the results of chemical and physico-chemical analyzes of Sherabad quartz sand and man-made waste, it was found that they can be added as glass components by cleaning them from various additives. [ABSTRACT FROM AUTHOR]

This experimental study investigated the performance of self-compacting concrete (SCC) mixes with magnesia (MgO) waste. In the series produced with a water/binder ratio of 0.40, cement was replaced by magnesia waste at 2%, 4% and 10% by weight in the SCC. Le Chatelier test, slump flow, compressive strength, flexural strength, depth of penetration of water under pressure, ultrasonic pulse velocity and water absorption by capillary testing was conducted to assess sample performance. X-ray diffraction, thermogravimetric analysis, mercury intrusion porosimetry, differential thermal analysis and scanning electron microscopy were used for the microstructural analysis and quantification of phases within each sample. The results indicated that concrete with magnesia waste contains magnesium silicate hydrate (M–S–H) and brucite ((Mg(OH)2) products. Brucite causes strength loss in concrete. Up to 90 days, specimens with magnesia showed increasing compressive and flexural strength. As the amount of magnesia waste increased, the porosity, depth of water penetration under pressure and water absorption by capillary increased. Incorporating more than 10% of magnesia waste in the SCC mixtures resulted in declining strength. The addition of magnesia waste enhanced the expansion of SCC. An optimum dosage (2%) of magnesia waste was the most advantageous to the strength of SCC. [ABSTRACT FROM AUTHOR]

This work investigated the effects of pulsed electric field (PEF) pretreatment, combined with different drying methods, on the quality of dried yams. The results showed that the pretreatment resulted in the formation of large pores in the yam tissues, thereby affecting the rehydration capability and hardness of the dried yam slices. The type of drying method after treatment did not alter the free radical stretching bands of yam. Additionally, the pretreated samples had a higher peak viscosity, through viscosity, final viscosity and break down, alongside lower pasting temperatures, To, Tp, Tc, and △H. Rheological measurements further indicated that all doughs exhibited solid-like behavior to different extents. The pretreatment also decreased the amount of allantoin and polysaccharides in dried yam slices, while negatively influencing their antioxidant activity. Finally, the choice of drying methods significantly affected the quality of the dried yams. In highlighting the effects of PEF pretreatment, combined with different drying methods, on dried yam, the results can help to expand their application within the food industry. [ABSTRACT FROM AUTHOR]

This work presents an improved structure of a single-phase muti-input multilevel inverter (MIMLI) for distributed energy resources, which is capable of producing a nine-level output in symmetric mode and 21 levels in asymmetrical mode. The topology uses four DC sources and ten switches, with four switches being bidirectional and the remaining unidirectional. The operation of the circuit is analyzed in an asymmetrical mode, and switching signals are accomplished using the Nearest Level Control (NLC) PWM technique. Depending on the value of the DC sources used, the number of levels can vary. In this work, different DC source algorithms were also proposed, and the analysis of the inverter has been carried out considering the algorithms producing the maximum number of levels. The inverter was simulated in MATLAB/Simulink under steady state and dynamic conditions, achieving a 3.89% THD in output. The thermal analysis was conducted using PLECS software 4.1.2 to assess losses and efficiency. A laboratory prototype of the proposed topology was developed and tested, confirming its performance through simulation results and proving it economically viable for medium- and high-power applications. [ABSTRACT FROM AUTHOR]

Today a lot of attention is paid to the formation of thermosensitive systems for biomedical and industrial applications. The development of new methods for synthesis of such systems is a dynamically developing direction in chemistry and materials science. In this regard, this paper presents results of the studies of a new synthesized supramolecular polymer system based on polyethylene glycol and tetrafluoroethylene telomers. The films formed from the polymer substance have the property of switching wettability depending on temperature after heating activation. It has been established that the wettability changes at 60 °C. The contact angle of activated hydrophobic polymer film reaches 143°. Additionally, the system exhibits its properties regardless of the pH of the environment. Based on data obtained by the methods of infrared and x-ray photoelectron spectroscopy, differential thermal analysis and thermal analysis in conjunction with wettability and morphology, a model of the behavior of molecules in a polymer system was built that ensures switching of the hydrophilic/hydrophobic surface state. The resulting polymer system, as well as films based on it, can be used in targeted drug delivery, implantation surgery, as sensors, etc. [ABSTRACT FROM AUTHOR]

To enrich the properties of polylactic acid (PLA)-based composite films and improve the base degradability, in this study, a certain amount of poly(propylene carbonate) (PPC) was added to PLA-based composite films, and PLA/PPC-based composite films were prepared by melt blending and hot-press molding. The effects of the introduction of PPC on the composite films were analyzed through in-depth studies on mechanical properties, water vapor and oxygen transmission rates, thermal analysis, compost degradability, and bacterial inhibition properties of the composite films. When the introduction ratio coefficient of PPC was 30%, the tensile strength of the composite film increased by 19.68%, the water vapor transmission coefficient decreased by 14.43%, and the oxygen transmission coefficient decreased by 18.31% compared to that of the composite film without PPC, the cold crystallization temperature of the composite film increased gradually from 96.9 °C to 104.8 °C, and PPC improved the crystallization ability of composite film. The degradation rate of the composite film with PPC increased significantly compared to the previous one, and the degradation rate increased with the increase in the PPC content. The degradation rate was 49.85% and 46.22% faster on average than that of the composite film without PPC when the degradation was carried out over 40 and 80 days; the composite film had certain inhibition, and the maximum diameter of the inhibition circle was 2.42 cm. This study provides a strategy for the development of PLA-based biodegradable laminates, which can promote the application of PLA-based laminates in food packaging. [ABSTRACT FROM AUTHOR]

As the use of antibiotics increases, the increasing resistance of bacteria is the main reason for the reduced efficiency of antibacterial drugs, making the research of new antibacterial materials become new hot spot. In this article, two novel coordination polymers (CPs), namely, [Cd2(L)2(bibp)2]n (1) and [Ni(L)(bib)]n (2), where H2L = N,N′-bis(4-carbozvlbenzvl)-4-aminotoluene, bibp = 4,4′-bis(imidazol-1-yl)biphenyl, and bib = 1,3-bis(1-imidazoly)benzene, have been synthesized under solvothermal and hydrothermal condition. Structural clarification was performed through infrared spectrum and single-crystal X-ray diffraction analysis, while thermal analysis and XRD technology were used for the performance assessment of compounds 1 and 2. In addition, antibacterial performance experiments showed that compounds 1 and 2 have certain selectivity in their antibacterial properties and have good antibacterial properties against S. aureus. As the concentration of the compound increases, the inhibitory effect gradually strengthens, and when the concentration of the compound reaches 500 μg/mL and 400 μg/mL, the concentration of the S. aureus solution no longer increases and has been completely inhibited. [ABSTRACT FROM AUTHOR]

Organic imidazolium hydrogen fumarate (IHF) crystals are grown using the slow evaporation method. The IHF has triclinic crystal structure. The 1H NMR spectrum has five chemical shifts for the IHF crystal. The band at 3155 cm−1 in IR occurs due to the presence of O─H stretching vibration of the IHF molecule. The bandgap value of the IHF crystal is determined to be 4.6 eV. The intense violet emission band is noted at 361 nm. The IHF crystal has thermal stability value of 179 °C. Hirshfeld surface is used to find out the different intermolecular interactions of the IHF crystal. The HOMO–LUMO energy gap is determined to be 4.70 eV. The hydrogen atoms have positive potential in the MEP analysis. The high stabilization energy of 56.81 kcal mol−1 is noticed for π*(C1─N7) → π*(C2─C3) interaction. The third‐order NLO susceptibility (χ(3)) of the IHF is 2.08934 × 10−9 esu. [ABSTRACT FROM AUTHOR]

An organic 5‐methyl‐1H‐imidazole‐3‐ium‐4‐carboxybutanoate (5MIC) co‐crystal is grown by slow evaporation solution growth technique (SEST) at room temperature. The 5MIC is synthesized using 4‐methylimidazole and glutaric acid in a 1:1 ratio using methanol as a solvent. The 5MIC crystal lattice parameters are identified using single‐crystal X‐ray diffraction analysis. The experimental X‐ray diffraction (XRD) and DFT structural parameter values have good correlations. The intermolecular interactions of the 5MIC crystal are found using Hirshfeld surface and 2D fingerprint plots. The computed C–N stretching vibration of the imidazole ring is observed at 1498, 1233, and 1064 cm−1. The HOMO is located on 4‐methylimidazole moiety of 5MIC molecule. Densities of state are used to find out the molecular orbital compositions of the 5MIC molecule. Mulliken analysis shows that the C13 (−0.86) atom has the lowest negative charge. The MEP surface color coded of 5MIC lies between 7.950 e−3 and −7.950 e−3. The 5MIC molecule has four types of intermolecular transitions. The first‐order hyperpolarizability (β) value of 5MIC molecule is 5.48×10−30 esu. The 5MIC crystal is thermaly stable up to 146 °C. The photoluminescence emission is observed from 400 to 600 nm. The 5MIC crystal shows SHG characteristics. [ABSTRACT FROM AUTHOR]

The thermal performance of the magnetic‐geared dual‐rotor machine (MGDRM) is investigated. Because the effective component in the outer airgap magnetic field harmonics is low, the torque production of MGDRM cannot match the regular permanent magnetic synchronous machine (PMSM). Although the analysis shows that the torque generation of the MGDRM is weak, this conclusion is limited in the electromagnetic field. The MGDRM outer rotor should also be considered from the thermal aspect, and the effect on the torque generation should be valued in particular. The outer rotor thermal buffer effect blocks the heating flow from the winding to the inner rotor magnets. Thus, the MGDRM can withstand a heavy electrical load in a short period, producing higher torque. With this understanding, the torque production ability of the MGDRM can extend to a higher level, even close to the regular PMSM. To validate the analysis, a MGDRM machine is prototyped, and the dual‐rotor temperature information acquisition is realised by a wireless data collection. The rotor temperature estimation technology on the dual‐rotor is then investigated as an auxiliary function. The estimation error can be limited around 5°C, which is good for warning the thermal risk. And thus the MGDRM overheating can be safely adopted to extend the torque generation. [ABSTRACT FROM AUTHOR]

The bark of Pinus radiata offers an underutilized source of high-value renewable chemicals such as extractable polyphenols and lipophilic compounds (waxes and suberin). Here, the depolymerization and extraction of suberin from P. radiata bark and its repolymerization to form novel polyesters are reported. Three different strategies were evaluated for repolymerization of the suberin monomers, with starting materials and products characterized using chemical and thermal analysis techniques. The inclusion of comonomer (1,12-dodecanediol) to provide stoichiometric balance improved the conversion, product yield, solubility and increased molecular weight. Enzymatic polymerization conditions gave the highest yield, while the highest molecular weight was achieved using titanium butoxide, demonstrating that polymerization conditions could be varied to target desired product properties. Products were hydrophobic, as shown by contact angles, ϴ ≥ 90° after 30 s. This work highlights opportunities for utilizing suberin to add value to a P. radiata bark biorefinery concept. Potential future applications include its use as a starting material for novel bio-based polymers that can serve as water-repellent surfaces and coatings, replacing established products derived from fossil resources. [ABSTRACT FROM AUTHOR]