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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]

To explore the effect of pressure on the combustion and luminescence properties of magnesium/nitrate pyrotechnics, combustion tests and thermal analysis of magnesium/sodium nitrate (N) and magnesium/strontium nitrate (S) pyrotechnic samples with zero oxygen balance were conducted under the pressure range of 101kPa-1kPa in this study. The results show that the flame height of N increases continuously as the pressure decreases, and the flames gradually change from a steady-state convergent flame to a turbulent evanescent flame. However, due to the different diffusion rates of the gas-phase combustion products, the diffusion of S at low pressure is lower and the flame still maintains a stable laminar flow. Although the light intensity and burning speed of both N and S satisfy Vier's law, the luminous intensity of S is less sensitive to pressure and still has good luminous performance at 1 kPa. Thermal analysis test results show that N and S can react almost completely at atmospheric pressure, and their enthalpies of reaction are 6.75 kJ/g and 6.07 kJ/g, respectively. The difference in the thermal decomposition histories of strontium nitrate and sodium nitrate at 1 kPa results in a reaction enthalpy of 4.24 kJ/g for S and only 2.45 kJ/g for N. This indicates that the reaction degree of S at low pressure is higher than that of N. The SEM-EDS test results further confirm this opinion. These scientific findings provide useful insights into the low-pressure combustion behavior of pyrotechnics and support the growing need for military and civilian applications. [ABSTRACT FROM AUTHOR]

High entropy alloys (HEAs) have attracted considerable research attention as potential substitute materials for austenitic steels in high-pressure hydrogen environments. The corresponding hydrogen absorption, diffusion and trapping has received less scientific attention. Therefore, the CoCrFeMnNi-HEA was investigated and compared to an austenitic steel AISI 316L. Both were subjected to high-pressure hydrogen charging at 200 bar and 1000 bar. Thermal Desorption Analysis (TDA) was used to clarify the specific desorption behavior and hydrogen trapping. For this purpose, the underlying TDA spectra were analyzed in terms of a reasonable peak deconvolution into a defined number of peaks and the activation energies for the respective and predominant hydrogen trapping sites were then calculated. Both materials show comparable hydrogen diffusivity. However, there were significant differences in the absorbed hydrogen concentrations at both charging pressures. The calculated activation energies suggest strong hydrogen trapping in the CoCrFeMnNi-HEA. • First time in-depth thermal desorption analysis study of 1000 bar charged CoCrFeMnNi-HEA. • Hydrogen solubility of CoCrFeMnNi is 132 wt.-ppm (part per million) at 1000 bar. • Preferred trapping of hydrogen at Cr and Mn in HEA (atom-hydrogen-bonding). • Importance of trap occupancy rate for increase in hydrogen solubility with pressure. [ABSTRACT FROM AUTHOR]

Efficient pretreatment methods are crucial for the generation of fermentable sugars from the renewable lignocellulose. In this study, γ-valerolactone (GVL), a biomass-derived green solvent, was used to fractionate corn stover (CS). The impact of different additives on the enzymatic hydrolysis and pretreatment of CS within the GVL/water system was carefully investigated. The results demonstrate that the use of H 2 SO 4 -assisted GVL/H 2 O (80:20, w/w) pretreatment at mild conditions successfully facilitates the depolymerization of CS, thereby improving the cellulase accessibility. Furthermore, by increasing the GVL pretreatment temperature to 160 °C with 100 mM H 2 SO 4 addition, the pretreated CS led to nearly 100 % of hydrolysis yield at 2 % (w/v) solid load. Finally, the thermogravimetric analysis (TGA) was performed to evaluate the thermal decomposition characteristics of untreated CS and enzymatic residues based on the H 2 SO 4 -assisted GVL/H 2 O pretreatment. The results indicate that the enzymatic residues had two depolymerization stages from 200 °C to 500 °C with a final residual mass of 22.73 %, which was higher than that of untreated CS (20.56 %). Overall, this study provides an efficient lignocellulose pretreatment for fermentable sugars production and valorization of enzymatic residues. [Display omitted] • Using H 2 SO 4 as γ-valerolactone (GVL) pretreatment additive enhanced xylan removal. • Glucose yield of GVL-pretreated corn stover (CS) was 3–5 folds higher than raw CS. • Sugars production reached 32.4 g/100 g CS by 50 mM H 2 SO 4 -assisted GVL pretreatment. • Enzymatic residues had two decomposition stages in 200–500 °C by thermal analysis. [ABSTRACT FROM AUTHOR]

Terrestrial heat flow plays a vital role in determining the present thermal regimes of sedimentary basins, offering a robust foundation for understanding hydrocarbon maturation processes and the geothermal resource potential. The Junggar basin is one of the largest and most petroliferous superimposed petroleum basins in China. However, research on heat flow is scarce. In this study, 94 new high-quality heat flow values are derived from through borehole temperature analysis and thermal conductivity measurements of rocks. The results indicate that (1) the geothermal gradient in the basin varies from 11.4 to 28.3 °C km−1, with a mean value of 20.9 ± 3.4 °C km−1, and the heat flow varies from 23.4 to 64.5 mW m−2, with a mean value of 45.1 ± 8.4 mW m−2. The overall low geothermal gradient and heat flow are attributed to the continuous cooling during the Meso-Cenozoic. (2) At basin scale, the high heat flow values are primarily concentrated in areas characterized by basement uplift, whereas the low heat flow values are mainly located in the depressions. This suggests that thermal refraction is the primary factor influencing the heat flow variations. (3) Although large-scale development and utilization of geothermal resources face challenges, certain local areas in the basin show promise for geothermal resource utilization. [ABSTRACT FROM AUTHOR]

In this study, an efficient optimization framework was developed to determine the parameters of through‐silicon vias and the layout of heat sources in three‐dimensional integrated circuits (3D ICs), employing an artificial neural network (ANN) reduced‐order model in conjunction with a Bayesian optimization (BO) algorithm. The proposed method effectively predicts the temperature distribution in 3D ICs and refines their thermal parameters, offering solutions to thermal management challenges. Latin hypercube sampling was utilized for data sampling, enhancing the previously established rapid thermal analysis method through parameterization of heat source locations. The temperature distribution data for varying hotspot locations in 3D ICs were fitted using an appropriately defined objective function, leading to the development of a reduced‐order ANN model that accelerates temperature prediction. The computational results demonstrate that the neural network model exhibits a deviation in predicted values of less than 2%, and the coefficient of determination R2 approximately 0.93, underscoring high predictive accuracy. Additionally, the optimization outcomes and the efficiency of the selected BO algorithm were thoroughly evaluated. Notably, the BO algorithm achieved the global optimum in just 4.07 s across 250 iterations, demonstrating an effective power distribution strategy for the 3D ICs model. [ABSTRACT FROM AUTHOR]

This study addresses challenges in elucidating the mechanism of phase transformations occurring in steel of near-peritectic composition. The importance of using and integrating, complementary experimental techniques is emphasized. While thermal analysis tools such as Differential Scanning Calorimetry (DSC) and Differential Thermal Analysis (DTA) are vital, they offer limited insight on events occurring during cooling. Employing standard thermal analysis (DSC) alongside high-temperature microscopy, incorporating simultaneous thermal analysis within a high-temperature microscope, and concentric solidification, two of steels of near-peritectic composition were investigated. Key findings include the correlation between heating rates and completion temperatures of phase transformation in the DSC heating experiments; absence of a peritectic transition inferred from DSC cooling curves supported by visual observation, and insights into restricted austenite phase nucleation attributed to diffusional constraint and limited nucleation sites. This investigation not only contributes to understanding phase transformation behaviour in peritectic steels, but more generally provides a framework for utilizing different techniques synergistically to address complexities in the interpretation of the mechanism of phase development. [ABSTRACT FROM AUTHOR]

This study investigated the impact and non-impact of tuned energy density (ED) on sinterability and other physicochemical characteristics of a sintered 3D-printed material tableting structure. The selected SLS 3D printer enables the alteration of direct ED values, which aids in analyzing the impact and non-impact of the overall process parameters, including hatch spacing (HS), laser scanning speed (LSS), layer thickness (LT), and laser power (LP). The progressively enhanced ED from 200 J/cm3 to 350 J/cm3 and 500 J/cm3 was impacted by the increased weight, hardness, and amorphization of the rifampicin (RIF) in the sintered 3D-printed material tableting structure. In the case of the surface morphology of sintered 3D-printed material tableting structure, inter-particle spaces were reduced, which increased neck formation and ultimately, increased consolidation. An increase in the ED decreased the average surface roughness of the sintered 3D-printed material tableting structure. The in vitro release of RIF diminished over 12 h as the ED progressively increased from 200 J/cm3 to 350 J/cm3 and 500 J/cm3. In addition, tuning the progressively enhanced ED had no impact on the printing yield, average thickness of the sintered layers, or thermal analysis of the 3D printed material tablet structures. The ultimate finding of this study is that it is necessary to optimize the ED and other sintering parameters according to the desired features of the sintered 3D printed material tableting structure. In addition, the utilization of SLS and incorporation of the co-processed polymer Eudragit L 100–55 in the printing process resulted in the release of RIF above physiological pH-5.5. This strategy effectively reduces the degradation of RIF under acidic conditions. Subsequently, the sintered 3D printed material tableting structures can be subjected to an in vivo pharmacokinetic study to confirm the obtained results. [ABSTRACT FROM AUTHOR]

The flexible control in burning rate and stable combustion of solid propellants over a broad range of pressures essentially determine the performance of solid rocket motors. The nanoscale metals and their oxides are usually utilized as the traditional burn rate modifiers in adjusting the combustion behaviors of solid propellants, but the energy characteristics of propellants are greatly compromised owing to the inert nature of additives used. In this paper, a series of metal complexes of triaminoguanidine-glyoxal polymer (TAGP-Ms) with high nitrogen content were synthesized and employed as energetic burn rate inhibitors in tunning the combustion properties of composite modified double-based (CMDB) propellants. The influences of prepared TAGP-Ms on the thermal decomposition and combustion of CMDB propellants were comprehensively investigated based on thermal analysis technique and combustion characterization methods. It was found that the peak temperatures of the second exotherm displayed for the propellants containing TAGP-Ms inhibitors were significantly increased by more than 30°C (except for TAGP-Cu), indicating the TAGP-Ms is capable of suppressing the thermal decomposition of CMDB propellants. More importantly, the heat releases of CMDB propellants were substantially enhanced by 16%~34% determined by DSC analysis. In comparison to the blank reference, the energetic TAGP-Ms inhibitors could promote the heat of combustion for the involved CMDB propellants by 5%~9%. The burning rates of CMDB propellants were notably reduced over a wide range of pressures by adding TAGP-Ms, whereas the calculated pressure exponents at pressures ranging from 10 to ~ 22 MPa appear to be relatively high due to the accelerated HMX decomposition. The measured combustion wave temperatures suggest that the CMDB propellants with TAGP-Ms undergo a three-stage combustion process with the highest temperatures in the range of 2160 ~ 2230°C. [ABSTRACT FROM AUTHOR]

Naturally Occurring Asbestos (NOA) has drawn the attention worldwide when investigation revealed an increased incidence of malignant mesothelioma in population living near NOA sites. In Basilicata region (South Italy), population living in the villages of Castelluccio Superiore and Inferiore, Lauria, Latronico, Episcopia, San Severino Lucano, and Francavilla in Sinni may be considered at high risk of asbestos exposure because these villages are either surrounded by or built on NOA-rich ophiolitic outcrops. In this work we investigated an asbestos tremolite sample coming from the ophiolitic rocks outcropping in the quarry of Iacolinei, widely used in the past to extract aggregates for various applications. A detailed mineralogical characterization has been attained by using a multi-analytical approach (EMPA, SEM-EDS, TEM-EDS, Mössbauer, µ-Raman, X-ray powder diffraction, and thermal analysis). Morphological investigation highlighted that the sample is composed of long fibers (> 5 µm) with a significant fraction (ca. 55%) having width below 0.25 µm, considered the most biologically active fibers. Moreover, the crystal chemical characterization showed that Fe occurs at the octahedral sites of the tremolite structure. It should be noted that Fe plays a primary role in the toxicity of asbestos. Based on these results, the investigated asbestos tremolite may be considered a potent mesothelial carcinogen, requiring therefore special attention for public health protection purposes. Investigations using sentinel animals to assess the diffusion of the tremolite fibers into the environment from the serpentinite rocks and soils of Iacolinei quarry are in progress. [ABSTRACT FROM AUTHOR]

Polyamide (PA) has excellent mechanical properties, making it versatile in various applications, including 3D printing. This paper comprehensively investigates and compares the mechanical, structural, thermal, and geometric properties of 3D‐printed PA12 samples produced with desktop and industrial printers using material extrusion (MEX) and powder bed fusion (PBF) processes. The mechanical tests included tensile, flexural, Charpy impact, Shore hardness, torsion, and water absorption tests. Additionally, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and melt volume rate (MVR) measurements are conducted. To verify printing accuracy from a biomedical perspective, 3D‐printed prosthetic fingers are subjected to geometric assessments. Industrial PBF samples show significantly higher values for most mechanical properties, including a tensile Young's modulus of 1776 ± 19.42 MPa, while the second highest value is 1419 ± 58.77 MPa (MEX desktop). Furthermore, the MVR of the PBF industrial samples is the highest (18.34 cm3/10 min ± 2.32 cm3/10 min) and this printer exhibits superior performance in printing accuracy than the other printers. The balanced print quality and mechanics make the PBF industrial printer the most recommended for medical device production, but lower‐priced desktop FFF printers can be a good alternative for simple, fast solutions that do not require high precision. [ABSTRACT FROM AUTHOR]

ABSTRACT The interaction of 2,6‐pyridinedicarboxylicacid (PDA) and 2,2′‐bipyridyl (Bipy) with Co(II), Ni(II), and Cu(II) ions produced new ternary complexes [M (PDA)(Bipy)(H2O)] (M = Co(II), Ni(II), and Cu(II)), which were studied by elemental, spectral (FT‐IR, Mass, UV–Vis), and thermal analysis, and their interaction with Ct‐DNA was thoroughly studied using various methods, including absorption spectroscopy, fluorescence spectroscopy, and viscosity measurements. Spectrophotometric titration and viscosity measurements indicated that all the complexes bind to DNA via the groove mode of binding. The salt‐dependent binding of ternary metal complexes to Ct‐DNA has been studied by a UV–Vis spectrophotometric titration experiment. Furthermore, photocleavage studies were used to examine how the metal complexes interacted with the pBR322 DNA, and the results proved that these compounds have obvious photo cleavage properties. The biological effects were studied by antibacterial activity. [ABSTRACT FROM AUTHOR]

The study examined the degradation process of various types of polymers used to form models using the fused deposition modeling (FDM) and three-dimensional printing (3DP) methods and used in the investment casting method. Commercial filaments made of polylactide (PLA), acrylonitrile butadiene styrene terpolymer (ABS), high-impact polystyrene (HIPS), polyamide 12 (PA12), poly(methyl methacrylate) (PMMA), and polypropylene (PP) were used to produce gypsum molds. The assessment included organic volatile compounds (VOCs) released during mold heating and model degradation, which is characteristic of this technological process. The screening qualitative chromatographic analysis of decomposition products sampled from various points of the production hall made it possible to define potential threats related to the processing of selected polymers and the necessary preventive measures. Furthermore, passive diffusion-type samplers were used at the sampling stage of VOCs emitted to the gaseous phase to reduce nuisance and user interference. Studies have been completed to characterize the thermoplastic polymer degradation process. The coupled thermogravimetry (TGA) with analysis of gaseous products by infrared spectroscopy with Fourier transformation (FT-IR) has been used. The presented results are the first to compare and rate the use of this still-developing novel aspect of castings by the method of fused models. [ABSTRACT FROM AUTHOR]

Reducing heat and improving the overall operation stability of the motor play a key role in the design of a starting engine. This paper focuses on the loss and thermal analysis of a permanent magnet (PM) brushless machine used in starter generators. The loss of the starter generator was calculated through a combination of theoretical analysis and the finite element method. A thermal analysis model was established based on the division of the fluid domain, boundary grid, heat source setting, and so on. The temperature fields of the whole motor and the main components were calculated and analyzed. The main factors affecting the air cooling effect were analyzed, including air flow rate, air temperature, and motor speed. A prototype experimental platform of the SG motor was built. The efficiency and temperature rise in the motor were tested. The temperature values were compared with the calculated values. The experimental results show that the performance of the motor is excellent, and the error between the temperature and the design calculation is less than 10% under each load torque. The accuracy of the thermal analysis method is verified. The correctness of the motor transient model was also confirmed through a temperature rise experiment under rated conditions, providing a research basis for improving operation efficiency. [ABSTRACT FROM AUTHOR]

The traditional passive heat dissipation method has low heat dissipation efficiency, which is not suitable for the heat dissipation of the concentrated heat source inside the long-focal aerial camera, resulting in temperature level changes and temperature gradients in the optical system near the heat source, which seriously affect the imaging performance of the aerial camera. To solve this problem, an active heat dissipation method of liquid cooling cycle is proposed in this paper. To improve the solving efficiency and ensure simulation accuracy, a dynamic boundary information transfer method based on grid area weighting is proposed. The thermal simulation results show that the liquid cooling method reduces the heat source temperature by 70.12%, and the boundary temperature transfer error is 0.015%. The accuracy of thermal simulation is verified by thermal test, and the simulation error is less than 6.44%. In addition, the performance of the optical system is further analyzed, and the results show that the MTF of the optical system is increased from 0.077 to 0.194 under the proposed active liquid cooling cycle heat dissipation method. [ABSTRACT FROM AUTHOR]

The maximum permissible load of underground power cables (known in U.S. engineering as "ampacity") is a function of many parameters, in particular, the thermal resistivity of the native soil. If this resistivity is relatively high, thermal/stabilized backfill is applied, i.e., another material is placed around the cables, providing favourable conditions for heat transfer to the environment. It has a positive impact on the reliability of the power supply and favours the operational durability of the cables. In design practice, however, there is a difficult task—correct determination of the ampacity of the cable line depending on the thermal parameters and the geometry of the backfill. Therefore, this article presents the results of a numerical analysis to determine the ampacity of cable lines in which stabilized backfill is used. A new mathematical relationship is proposed that allows the correction of the ampacity of cable lines depending on their cross-section as well as the thermal and geometric parameters of the cable surroundings. [ABSTRACT FROM AUTHOR]

Wood–plastic recycled composite (WPRC) are composites obtained by heating and mixing the main raw material, wood flour, with thermoplastic resin, containing at least 40% by mass of recycled material in the raw material. In order to promote the multiple-recycling of WPRC to reduce greenhouse gas emissions and ensure the sustainability of resources, three types of WPRC decking materials with different exposure conditions (outdoor-exposed product, unexposed product and product stored in the factory for a long time) and samples after accelerated weathering tests (WPRC and recycled plastics from raw materials) were evaluated and compared by a TG-DTA in order to develop a method for evaluating the degree of degradation of used WPRC. Exothermic behavior with weight loss was observed in the temperature range of 30–500 °C for the WPRC product in two temperature ranges. In order to focus on the change in the first exotherm by oxidative degradation, where the rapid weight loss begins, this paper will focus on the exothermic behavior that develops in the temperature range of 150–300 °C on the lower temperature side. The results obtained are as follows. (1) Initial oxidation temperature (IOT) measurement from DTA behavior suggested that it is possible to evaluate the degree of degradation of WPRC. (2) On the exposed surface of WPRC exposed outdoors for more than 9 years and 8 months, significant decreases in the IOT were observed up to 1 mm from the surface, and a slight decrease in the IOT was observed between 1 and 2 mm from the surface. On the other hand, for the indoor long-term storage of 11 years and 6 months, there were almost no changes in the IOT with respect to the depth from the surface. Regarding the outdoor long-term-exposed WPRC, significant decreases in the IOT were observed not only on the exposed surface but also on the hollow and ribbed surfaces up to a depth of 1 mm from the surfaces. (3) A similar decrease in the IOT with increasing accelerated degradation time was observed for the WPRC and raw recycled plastic samples after accelerated weathering tests as for outdoor exposure. Furthermore, FTIR-ATR spectra also revealed that accelerated degradation caused oxidative degradation of the plastic. Therefore, it is thought that the decrease in the IOT can be used as an indicator to evaluate the degree of degradation of the plastic raw material in WPRC. [ABSTRACT FROM AUTHOR]

Diabetic wound healing remains a challenging issue, necessitating advanced dressings with active therapeutic agents to reduce inflammation and promote healing. Ecklonia cava phlorotannin (ECP) possesses therapeutic potential for wound healing including anti‐microbial, antioxidant, and anti‐inflammatory properties. Our previous study demonstrates the therapeutic efficacy of ECP‐loaded nanofibers in an in vitro hyperglycemic wound model. The present paper focuses on the detailed characterization of the polyvinyl alcohol (PVA)/polyvinylpyrrolidone (PVP) blend nanofiber incorporated with ECP. The ideal ratio, PVA80:PVP20, is selected to incorporate with ECP via the blend electrospinning method. To confirm the successful loading of ECP (0.5% and 1%), physicochemical characterization is conducted using scanning electron microscopy, Fourier‐transform infrared spectroscopy, and thermal analysis. Functionality assays are performed to evaluate their applicability as dressing biomaterials. Physicochemical analyses confirm the successful loading of ECP into the nanofibers. Overall, the ECP‐loaded PVA/PVP nanofiber membranes exhibit favorable wound dressing criteria, which attributed to high water absorption capacity (200%–400%), sufficient water vapor transmission rate (1550–1650 g/m2/d), high loading efficiency and slow release. Bioactivity tests indicate that the ECP's effectiveness is unaffected by the electrospinning process. Importantly, these membranes exhibit biocompatibility and nontoxicity to human dermal fibroblasts, indicating their potential as good diabetic wound dressings. [ABSTRACT FROM AUTHOR]

We report on temperature‐dependent structural and spectroscopic properties of two new members of the mullite‐type ceramics SnAlBO4 and SnGaBO4. In‐situ X‐ray powder diffraction (XRPD) demonstrates positive thermal expansion behavior for all orthorhombic lattice parameters between 13 and 840 K. The lattice thermal expansion is modeled by Grüneisen first‐order approximation, where the vibrational energy is calculated by the Debye–Einstein–anharmonicity (DEA) approach. Although the thermal changes of the metric parameters do not show any discontinuity, the double‐Debye model and low‐temperature thermal analysis leave hints for subtle displacive changes. Splitting of the tin‐doublets of the 119Sn Mössbauer spectra at low temperature is assumed to be associated with structural modulation although the temperature‐dependent Raman spectra could not support these findings. The modulation could either be dynamic which requires much longer thermal equilibration than the speed of the data collection for XRPD and Raman spectroscopy. Selective Raman mode frequencies are analyzed using a modified Klemens model, which helps to understand the thermal anharmonic behaviors of the SnO4, MO6, and BO3 polyhedra as a function of temperature. [ABSTRACT FROM AUTHOR]

Six new semi-IPN hydrogels using 2-acrylamido-methylpropane-1-sulfonic acid (AMPS) and Gelatin at different ratios through redox polymerization were prepared. Methylene-bisacrylamide and glutaraldehyde were used as the crosslinking agents for AMPS and Gelatin, respectively. The hydrogels’ swelling ratios and surface morphologies were analyzed using SEM for characterization. Porosity and specific surface area using the Brunauer–Emmett–Teller technique. DSC and Tg were also used for the thermal analysis of the prepared hydrogels, which show trans-glass temperature (Tg) higher than their raw materials AMPS and Gelatin. The prepared hydrogels were used to eliminate the cationic dye MB from the water-based solutions with an initial concentration of 600 ppm. The study discovered that the N9 and N10 hydrogels were extremely effective at removing a certain dye from aqueous solutions with an optimum pH level of 11 and an optimum temperature of 65°C. Both N9 and N10 achieved high removal efficiencies, reaching equilibrium at 90 min, whereas the other hydrogels required 120 min. N9 performed slightly better at 1078.919 mg/g and N10 at 1057.404 mg/g. The adsorption behavior of the two hydrogels followed the Langmuir model. The hydrogels exhibited pseudo-second-order kinetics. The thermodynamic study cleared that the adsorption of MB dye was endothermic and spontaneous. Results also showed that the adsorption of dyes with hydrogels N9 and N10 is chemisorption in nature. Desorption studies were conducted using 0.1 M HCl and NaOH. HCl was found to be the best eluent for dye recovery. [ABSTRACT FROM AUTHOR]

ABSTRACT This work presents a step‐by‐step approach for replacing Si‐IGBTs with SiC‐MOSFETs modules in a 9‐kW commercial double‐conversion UPS. Incremental modifications are applied to the original system, considering variations in switching frequency and evaluating its influence on losses and total volume. Through the use of Si‐IGBT transistors and redesigning the system, the volume and losses are analyzed for switching frequencies between 10 and 17 kHz. The IGBT showed limitations around 17 kHz, with high losses due to tail current. With SiC‐MOSFETs, the switching frequency is increased, resulting in smaller filter volumes. The SiC module allowed operation at frequencies in the tens and hundreds of kHz, with relatively low switching losses, which significantly reduced the volume of filters and heat transfer systems. These technological advancements resulted in reductions of up to 78% in the total volume and improved efficiency, enabling operation at lower temperatures and potentially increasing the lifetime of components. [ABSTRACT FROM AUTHOR]

AbstractOligomeric poly(α-methyl-β-alanine)with vinyl end-group (PmBA) was synthesized via base-catalyzed hydrogen-transfer polymerization (HTP) of molten methacrylamide (MAm) in the presence of sodium tert-butoxide (t-BuONa). The PmBA was used as a comonomer in the synthesis of amphiphilic poly(2-hydroxyethyl acrylate-g-α-methyl-β-alanine) (PHEA-g-PmBA)via nitroxide-mediated polymerization (NMP)and "grafting through" approach.The graft copolymer formation was confirmed byproton nuclear magnetic resonancespectroscopy (1H-NMR), Fourier-transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and static light scattering (SLS)measurements. Thermogravimetric analysis of the amphiphilicPHEA-g-PmBAexhibited a multi-step decomposition curve corresponding to the α-methyl-β-alanine and the 2-hydroxyethyl acrylate blocks at about 306, 369, and 403 °C.DSC curve of the copolymer has a baseline shift at −12.87 °C attributed to the glass transition temperature. SLS analysis of the final product resulted in a weight average molecular weight of 83.6 kDa. The spectroscopic and thermal analyses proved that amphiphilicPHEA-g-PmBA was successfully synthesized through HTP and NMP. [ABSTRACT FROM AUTHOR]

We present a set of six time-temperature (tT) histories, called benchmark paths, that can be used as a shared framework for evaluating the sensitivity of a thermochronologic system to the variables inherent in the interpretation of thermochronologic data (e.g., kinetics models, mineral compositions or geometries, etc.). These benchmark paths span 100 Myr, include monotonic and nonmonotonic histories that represent plausible geologic scenarios, and have a range of cooling rates through different chronometer partial-retention/annealing temperatures. Here, we demonstrate their utility by presenting a method for tuning these paths to 11 different kinetics models for the apatite (U-Th-Sm)/He (n=5), apatite fission-track (n=2), and zircon (U-Th)/He (n=4) systems. These tuned tT paths provide a practical comparison of the kinetics models for each system and the data patterns they predict, thereby offering anyone performing thermal history analysis the ability to consider how their choice of kinetics model may impact their data interpretation. The adoption of benchmark paths for evaluating kinetics models and other variables provides a practical way for the thermochronology community to evaluate and communicate the decision making processes that are inherent in thermochronologic modeling and data interpretation. [ABSTRACT FROM AUTHOR]

Polyethylene terephthalate glycol (PETG) is a novel amorphous shape memory polymer with excellent printability for 4D printing. In this article, ethylene‐vinyl acetate (EVA) is used as a biocompatible and non‐toxic copolymer to improve plasticity and shape memory performance of PETG. PETG‐EVA blends are prepared and 3D printed using a melt mixing method and an upgraded fused deposition modeling (FDM) with a pneumatic feeding system. The results of the thermal analysis show that the blends exhibit two tan‐delta peaks, each related to their components, and morphology images confirm that they are biphasic and immiscible with good compatibility. The morphology of both EVA10 and EVA30 matrix droplets is observed, with the droplets being larger for EVA30. The use of a pneumatic feeding system, along with the ability to control the output melt flow, results in the best printing ability for EVA30, with minimal microholes between the grids and interlayer cracks. The tensile strength of PETG‐EVA blends ranged from 25.38 to 20.14 MPa, with the highest tensile strength achieved for EVA30. The shape memory performance of all three blends is similar; with shape recovery exceeding 90% in 20 s. Blends with higher EVA content exhibited faster shape recovery within the first 10 s. [ABSTRACT FROM AUTHOR]

The Leighton Chajnantor Telescope (LCT) is an international collaborative program among Caltech, Shanghai Normal University (ShNU), and Universidad de Concepción (UdeC), aiming at the refurbishment and relocation of the Caltech Submillimeter Observatory (CSO) telescope from Mauna Kea, Hawaii, to the Chajnantor Plateau, northern Chile. A suite of excellent-sensitivity heterodyne superconductor–insulator–superconductor (SIS) receivers will be deployed to the telescope as the first set of instrumentations for high-resolution spectral observation. However, the current refrigeration technology for this receiver utilizes liquid helium (LHe), which greatly increases the cost of cooling and labor. To address this problem, a new LHe-free cryostat for the LCT heterodyne SIS receiver has been designed, fabricated, and tested. Mechanical and thermal analyses were performed to ensure that the cryostat meets the requirements of the telescope pointing accuracy and the SIS junction working environment, respectively. The experiment testing results are in good agreement with the calculation and analysis, indicating that the proposed LHe-free cryostat meets the operational requirements of the telescope at the new site. [ABSTRACT FROM AUTHOR]

Thermal lens spectrometry is a high-sensitivity method for measuring the optical and thermal parameters of samples of different nature. To obtain both thermal diffusivity and absorbance-based signal measurements with high accuracy and precision, it is necessary to pay attention to the factors that influence the trueness of photothermal measurements. In this study, the features of liquid objects are studied, and the influence of optical and thermal effects accompanying photothermal phenomena are investigated. Thermal lens analysis of dispersed solutions and systems with photoinduced activity is associated with a large number of side effects, the impact of which on trueness is not always possible to determine. It is necessary to take into account the physicochemical properties and optical and morphological features of the nanophase and components exhibiting photoinduced activity. The results obtained make it possible to reduce systematic and random errors in determining the thermal-diffusivity-based and absorbance-based photothermal signals for liquid objects, and also contribute to a deeper understanding of the physicochemical processes in the sample. [ABSTRACT FROM AUTHOR]

Manganites of rare earth elements are currently promising materials for electronics, catalysis, current sources and other applications. Their widespread demand is caused by a variety of structural and magnetic effects connected with substitutions in the sublattices of rare earth element and manganese. Substitutions of rare earth element by Sr, Ca, or Ba in manganites are known to impact the Jahn-Teller (JT) transition temperature as well as the concentration of Mn3+ and Mn4+ ions, which influences the efficiency of double exchange in magnetic orderings. In this work, solid solution Sm1-xSrxMnO3 with low concentrations of the substituting element x = 0; 0.15; 0.25 has been studied using X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermal analysis, and magnetometry. Samarium manganites have a perovskite-like orthorhombic structure (Pbnm space group). It has been shown that the Sm-by-Sr substitution leads to a gradual increase in the valence of manganese from 3 + to intermediate value 3.67+. This is accompanied by an increase Néel temperature in (TN) from 56 K at x = 0 to 90 K at x = 0.25, in the paramagnetic Curie temperature (Θ) from − 30.3 K at x = 0 to 119.9 K at x = 0.25, as well as in the value of the saturation magnetic moment (µS) from 0.27 µB at x = 0 to 3.49 µB at x = 0.25. In addition, such substitution leads to a decrease in the temperature of the JT structural transition from 996 ºC at x = 0.0 to 252 ºC at x = 0.25. The relationship between the magnetic properties and the crystal structure of samarium manganites is discussed. [ABSTRACT FROM AUTHOR]

The 50th annual conference of the North American Thermal Analysis Society is being held jointly with the 8th Baekeland Symposium to bring those communities together. NATAS offers scientists and practitioners the opportunity to explore the frontiers of thermal analysis, rheology, and materials characterization, learn of developments in instrumentation and software, as well as applications in a variety of industrial settings. The Baekeland Symposium has a record of showcasing the latest scientific, technical and industrial innovations in the field of high performance thermosetting polymers. This year is the first joint meeting of the two organizations and is expected to provide opportunities for new collaborations and exchange of ideas. Presentations and posters by renowned scientists and graduate students set the stage for excellent discussions and an ideal environment to learn about state-of-the-art techniques and exciting new developments in thermal analysis and materials research. [ABSTRACT FROM AUTHOR]

To investigate the effect of hydrogen bonding interactions between precursors on the structure and performance of the target catalysts. The dicyanodiamine/glucose (DCDA/GLC) precursors with hydrogen bonding interactions were prepared by a simple hydrothermal method, and g-C3N4-based (GCN-X) composite photocatalysts were further prepared by subsequent thermal polymerization. Through the analysis of thermal decomposition kinetics and structural characterization, the relative enhancement of the strength of hydrogen bonding interactions in the structure of the DCDA/GLC-2 precursor could effectively promote the transformation process of dicyandiamine to melamine. Glucose in the precursor, which formed a part of monolithic carbon, was attached to the surface of g-C3N4. The ultimately obatained GCN-2 possessed a stronger visible-light absorption ability, better conductivity and charge transfer efficiency. Thus, GCN-2 exhibits better photocatalytic activity. [ABSTRACT FROM AUTHOR]

The current study aims to take a step forward in understanding the morphological changes of Fe-rich intermetallics using Fe correctors. Specifically, minor additions of molybdenum (Mo) and vanadium (V) were employed to investigate the morphological changes in hard β-phases (β-Al5FeSi) into granular α-phases in Al–Si–2.5Fe scrap alloy. The microstructure and composition of the intermetallic phases were characterized using SEM-EDS, Xrd, and optical microscopy. The combined effect of vanadium and molybdenum showed significant improvement in intermetallic formation while suppressing the platelet β-Al5FeSi morphologies. Interestingly, a new quinary AlSiFeMoV phase was discovered through SEM-EDS and XRD. Thermal analysis was performed to investigate the influence of Fe-rich intermetallics in the presence of alloying additions V and Mo. Moreover, the microstructure revealed various α-phase morphologies, including quadrilateral, polygonal, and Chinese script structures, which were subjected to detailed intermetallic analysis in this study. A hardness test was performed to understand the effect of Mo and V additions on the Al–Si–2.5Fe scrap alloy. A synergistic effect was observed at 1 wt.% of Mo and V additions in the scrap alloy revealed that significant drop up to 17.19% hardness was observed in the synergistic-affected alloy. [ABSTRACT FROM AUTHOR]

The effect of copper addition, solution heat treatment and aging on Al-Zn-Mg alloy's microstructure, mechanical and thermal properties is studied using an optical microscope (O.M.), scanning electron microscope (SEM), X-ray diffractometer (XRD), Micro-Vickers hardness, universal tensile machine (UTM) and differential scanning calorimetry (DSC). Al-Zn-Mg-xCu (0.02 wt% and 0.89 wt%) alloys are made using 5754 alloys, pure zinc and Al-Cu alloy. After casting, Al-Zn-Mg-xCu (0.02 wt% and 0.89 wt%) alloys are heat-treated in a solution (480 °C for 1 h). After solution heat treatment, aging (180 °C for 10 to 60 minutes) is applied. As-cast Al-Zn-Mg-xCu (0.02 wt% and 0.89 wt%) alloys contain η (MgZn2) phase and T (Al2Mg3Zn3) phase. After solution heat treatment, the η and T phase dissolves into a supersaturated solid solution. Adding copper into Al-Zn-Mg alloys increases hardness from 115.94 to 135.22 HV1. Solution heat treatment improves the hardness and strength due to the dissolution of precipitate phases and the formation of solid solution atoms. Aging improves hardness due to the formation of coherent G.P. zones. Adding copper decreases the precipitate phase's dissolution temperature from 472.2 to 468.6 °C. [ABSTRACT FROM AUTHOR]

Alternative hypotheses have been proposed regarding how the hormone corticosterone (CORT) mediates energy expenditure during reproduction. Elevated baseline CORT (CORTb) could support daily energy expenditure (DEE), promoting reproductive effort or downregulate costly behaviours in low quality individuals facing allostatic overload.We investigated relationships between CORTb, time activity budgets (TABs), DEE and diving behaviour across 2 years and colonies of little auk (Alle alle), an Arctic seabird in which elevating DEE may support reproduction in the face of climate change.We also explored whether mercury (Hg) contamination might suppress DEE by affecting the hypothalamus‐pituitary–adrenal (HPA) axis and CORT production.Furthermore, we performed phylogenetically controlled analysis across breeding seabird species to build broader understanding of CORT‐DEE relationships.CORTb positively correlated with little auk activity, DEE and dive duration during a cold year in East Greenland, when CORTb was elevated in the population, but not during a warmer year, or at Svalbard. CORTb did not predict chick provisioning nor did Hg suppress CORTb.Across breeding seabird species, CORTb and DEE were uncorrelated. Rather, contrary to predictions, CORTb was higher in species breeding at lower latitudes.Intraspecific results suggest environment‐dependent relationships between CORTb, behaviour and DEE, with implications for understanding CORTb's role in climate change resiliency.Interspecific analyses suggest absence of correlational selection between CORTb and DEE during reproduction, and that DEE thresholds that induce changes in CORTb might differ between species. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Thermogravimetry (TG) is used to measure the change of sample mass versus temperature or time under a program controlling temperature. It is a common thermal analysis tool with a precise built-in balance, and accurate data can be obtained through a small amount of sample at the level of milligrams. The feasibility of the TG method for determining maximum water content (MWC) measurement of waterlogged archaeological wood was studied. Simulated waterlogged wood and waterlogged archaeological wood were used to determine the test condition for the TG method. MWC data obtained through the oven-dry and TG methods with different mass gradients from 0–10 mg to >50 mg were analyzed statistically. Deviation, error bar, and coefficient of variation were evaluated. According to the results, when sample mass is no less than 30 mg, and holding time at 105°C is no less than 40 min, data deviation between these two methods is less than 5%. Effect of sampling depth and presence of inorganic deposits were also investigated. Specimens were taken from an archaeological wood with a sampling depth from 2 to 6 mm, then MWC was measured through the TG method. The results indicate MWC of the samples taken from a depth of 2–4 mm is higher than that taken from a depth of 0–2 mm and is lower than that taken from a depth of 4–6 mm, which is related to inorganic deposits. The presence of deposits was verified through SEM-EDX. MWC of three archaeological wood samples from China and five archaeological wood samples from Italy were measured to verify the effectiveness of the TG method when wood species and degradation degree are different. [ABSTRACT FROM AUTHOR]

Non-destructive inspection and analysis techniques are crucial for quality assessment and defect analysis in various industries. They enable for screening and monitoring of parts and products without alteration or impact, facilitating the exploration of material interactions and defect formation. With increasing complexity in microelectronic technologies, high reliability, robustness and thus, successful failure analysis is essential. Machine learning (ML) approaches have been developed and evaluated for the analysis of acoustic echo signals and time-resolved thermal responses for assessing their ability for defect detection. In the present paper different ML architectures were evaluated, including 1D and 2D convolutional neural networks (CNNs) after transforming time domain data into the spectral- and wavelet domains. Results showed that 2D CNNs processing data in wavelet domain representation performed best, however at the expense of additional computational effort. Furthermore, ML-based analysis was explored for lock-in thermography to detect and locate defects in the axial dimension based on thermal emissions. While promising, further research is needed to fully realize its potential. [ABSTRACT FROM AUTHOR]

Localizing security-relevant hard blocks on modern System-on-Chips for physical attacks, such as side-channel analysis and fault attacks, has become increasingly time-consuming due to ever-increasing chip-area and -complexity. While this development increases the effort and reverse engineering cost, it is not sufficient to withstand resolute attackers. This paper explores the application of camera-based lock-in thermography, a nondestructive testing method, for identifying and localizing security hard blocks on integrated circuits. We use a synchronous signal to periodically activate security-related functions in the firmware, which causes periodic temperature changes in the activated die areas that we detect and localize via an infrared camera. Using this method, we demonstrate the precise detection and localization of security-related hard blocks at the die level on a modern SoC. [ABSTRACT FROM AUTHOR]

Aluminum-boron composite powders were prepared mechanical milling and consolidated using uniaxial pressing. Both, spheroidal and irregularly shaped powders were prepared from the same starting materials. The product powder morphology was determined by the type of liquid process control agent. Highest strength was observed for the pellets made of spheroidal powders without any binder. For all milled powders, the main oxidation exotherm was delayed compared to the blended starting materials. For the pellets made of spheroidal powders heated in inert gas, an exotherm initiated just above 400°C while no such exotherm was detected for the pellets pressed using other composite powders. [ABSTRACT FROM AUTHOR]

In this study, four new heteronuclear hexacyanoferrate(III) and hexacyanocobaltate(III) complexes, namely, [Cu2(4mpy)2Cu(4mpy)2(EtOH)2Co2(µ-CN)8(CN)4]n (1), [Zn2(4mpy)2Zn(4mpy)2Co2(µ-CN)10(CN)2]n (2), [Cd2(H2O)8Cd(4mpy)2Co2(µ-CN)8(CN)4]n (3) and [Cd3(4mpy)12Fe2(µ-CN)6(CN)6]n (4), were synthesized using 4-methylpyridine (4mpy) ligand. All complexes were investigated using single-crystal X-ray diffraction (SC-XRD), vibration (FT-IR and Raman) spectra and elemental and thermal analysis techniques. In addition, powder X-ray diffraction (PXRD) patterns were performed to verify the phase purity of the complexes. Crystallographic analyses reveal that complexes 1, 2 and 4 exhibit 2D structure while complex 3 exhibits 1D structure. Also, the 3D supramolecular structures of the complexes 1–4 formed through intermolecular C-H···N, O–H···N or O–H···O hydrogen bonding. [ABSTRACT FROM AUTHOR]

The ARIEL mission is a European space project that aims to detect exoplanets with a spacecraft orbiting around the L2 point of the Sun-Earth system. The main payload consists of a Cassegrain telescope composed of mirrors that reflect and concentrate the incoming light from the deep space observations to finally guide it to the detectors. As in many other space missions, a dedicated complex assessment is established during the design phase to evaluate the impact on the optical performance caused by thermoelastic effects, which involves the coordinated work of the thermal, structural, and optical engineers. Despite that well-known and standardized processes and tools are established separately in each involved area, there is a lack of standardization about the way of exchanging the data between them, where additional calculations are required in some cases. This work focuses on the temperature mapping, which is the intermediate step between thermal and structural analyses, where temperatures are transferred to the structural model. The main difficulty of this process is related to the differences in modelling methods and approaches between both models, being necessary the development of an adequate algorithm to find the most accurate transfer of temperatures. This paper shows two different options for temperature mapping, detailing the proposed flowcharts. One of these methods requires the performance of an additional thermal conductive analysis, where a new improved procedure has been implemented in this work to solve some computational issues that made its application for large models difficult or even unfeasible. Both temperature mapping methods have been applied to the payload module of the ARIEL spacecraft, comparing the output results in terms of temperatures, stresses, forces, and displacements to evaluate their differences. • Structural, Thermal and Optical Performance (STOP) analysis on the ARIEL spacecraft. • Development of two procedures for temperature transfer between thermal and structural models. • Definition of a process to overcome computational issues found in thermal analysis in NASTRAN. • Validation of the proposed procedures for the temperature mapping of a large and complex model. • Comparison of results between two temperature mapping methods (PWT and PAT) on ARIEL. [ABSTRACT FROM AUTHOR]

A 100-W radioisotope thermoelectric generator (RTG) is by far the most suitable power supply for long-term deep space exploration where solar power would not be feasible. Understanding the thermal performance and electrical performance of the RTG under operational conditions is paramount for its nominal and safety performance during the space mission. In this paper, modeling and experimental studies on the thermal behavior and electrical performance of the 100-W RTG have been conducted. The RTG uses high conversion efficiency skutterudite-based thermoelectric convertor (TEC) arrays thermally coupled with a radioisotope heat unit (RHU) to generate electricity. A comprehensive finite element model and an electrical heating prototype of the 100-W RTG have been built to assess the performance of the RTG designs. Critical temperature, generated power, and energy conversion efficiency were evaluated. The simulation results show that the maximum output power of the RTG can reach about 120 W(electric); the temperature of the hot end of the TECs is about 853 K, and the temperature of the cold end is about 473 K, making a temperature difference of about 380 K. The RTG prototype with Bi2Te3 TECs generated about 60 W(electric) of electrical power in the first experimental research stage. These research results have significant reference for extension of the RTG prototype to the actual power source of the RHU and allow for future research and development improvements of the 100-W RTG. [ABSTRACT FROM AUTHOR]

Three new organic–inorganic hybrid phosphites salts, namely, (enH2)[M(H2O)6](HPO3)2, with [M = Co (1), Ni (2) and Mg (3), and "en" refers to ethylenediamine C2N2H8] have been synthesized at room temperature by the slow evaporation method. The solid-state structures were solved from single crystal X-ray diffraction data. These compounds are isostructural, all crystallizing in the orthorhombic system, space group, Pbca (no 61). The FTIR spectroscopy shows the expected bands of ethylenediamine (en), water molecules, and hydrogen-phosphite oxoanion groups. The thermal stability until 100 °C of the three compounds was confirmed using combined analyses (TGA/DTA, powder X-ray diffraction and Raman spectroscopy). Two catalytic activity performances were investigated: the catalytic efficiency on the water decontamination of the three compounds by the reduction of three nitrophenol isomers and the Hydrogen Evolution Reaction (HER) in an alkaline environment. The three hybrid compounds turned out to be very efficient new catalysts for reducing the three nitrophenol isomers. The fastest electron transport and the most favorable HER reaction kinetics are displayed by (enH2)[Ni(H2O)6](HPO3)2, while the highest current density with the lowest overpotential was obtained for (enH2)[Co(H2O)6](HPO3)2. [ABSTRACT FROM AUTHOR]

The degradation of different flexible polyurethane foams for molded application after thermal aging were compared. A reference sample using traditional higher emission additives and four samples of different composition using low-emission additives were compared. For the modified samples volatile organic compound (VOC) and semi-volatile organic compound (FOG/SVOC) contents fell well below the benchmarking limits, which indicates that the selected low-emission additives are incorporated into the polymer chain. To examine different material properties and for evaluating changes due to increased temperature exposure for a prolonged period of time mechanical and acoustic tests were carried out before and after dry heat aging. It was found that two low emission samples exhibited superior sound absorption compared to the reference sample along with less significant change after aging in the acoustic properties. The compressive strength was lower than the reference as a result of lower product densities. However, the change in compressive strength after aging was less than 15% (with one exception), which is acceptable according to the standard requirements. Thermogravimetric analysis was also performed and revealed that no significant difference can be observed between the examined samples due to heat degradation, indicating that the modifications made to reduce VOC content did not adversely affect the foam’s resistance to thermal degradation. [ABSTRACT FROM AUTHOR]

Stratospheric balloons are platforms with great relevance in space missions to reach scientific observations. The payload thermal analyses of such missions are usually focused on the float phase. However, during the ascent phase, the coolest temperatures of the entire mission may be reached, mainly due to the convective cooling in the tropopause. This can be explained by the combination of relative wind speed and the harsh thermal environment. The aim of this work is to evaluate the impact of the thermal environment on the relative wind speed to determine the worst-case thermal analysis. Therefore, in order to perform a robust payload thermal during the ascent phase, the uncertainty in the thermal environment and the relative velocity must be evaluated. The former are reduced by defining the thermal environment based on real-data. The latter are reduced by evaluating the parameters involved in the ascent rate. For this purpose, a dynamic model has been developed to characterise the ascent rate and the horizontal relative velocity of the balloon-borne system. This tool has been validated with flight data from the REXUS/BEXUS programme, with the BEXUS missions launched from Esrange, Kiruna, Sweden from 2014 to 2018. The thermal analysis performed shows a temperature difference greater than 10 °C depending on the thermal worst-case selection. The work here presented reduces the uncertainties of the stratospheric payloads ascent phase thermal analysis. [ABSTRACT FROM AUTHOR]

This review summarizes the effects of mechanical impact on crystal lattices of some inorganic substances (Si, S, NaCl, KCl, CaO2, BaO2, YBa2Cu3O7–x, hematite α-Fe2O3, ordinary glass Na2O ∙ CaO ∙ 6SiO2) in a centrifugal mill. It was found that powder particles subjected to short-term impact-shear loading are deformed and reduced in size, and have structural damage after grinding in the mill. Examination of disordered compound particles showed that the resulting activated states have a certain amount of energy. Intensive mechanical activation in a centrifugal mill leads to an excess enthalpy and a change in the properties for all studied compounds. The results obtained can be used in exploratory studies of substances and materials using various mechanochemical reactors. [ABSTRACT FROM AUTHOR]

Estimating energy flows that affect temperature increases inside houses is crucial for optimizing building design and enhancing the comfort of living spaces. In this study, a thermal model has been developed to estimate the internal temperature of rural houses in Mexico using aerial thermography. The methodology used in this study considered three stages: (a) generating a semi-experimental thermal model of heat transfer through roofs for houses with high infiltration, (b) validating the model using contact thermometers in rural community houses, and (c) integrating the developed model using aerial thermography and Python 3.11.4 into user-friendly software. The results demonstrate that the thermal model is effective, as it was tested on two rural house configurations and achieved an error margin of less than 10% when predicting both maximum and minimum temperatures compared to actual measurements. The model consistently estimates the internal house temperatures using aerial thermography by measuring the roof temperatures. Experimental comparisons of internal temperatures in houses with concrete and asbestos roofs and the model's projections showed deviations of less than 3 °C. The developed software for this purpose relies solely on the fundamental thermal properties of the roofing materials, along with the maximum roof temperature and ambient temperature, making it both efficient and user-friendly for rural community management systems. Additionally, the model identified areas with comfortable temperatures within different sections of a rural community, demonstrating its effectiveness when integrated with aerial thermography. These findings suggest the potential to estimate comfortable temperature ranges in both rural and urban dwellings, while also encouraging the development of public policies aimed at improving rural housing. [ABSTRACT FROM AUTHOR]

In recent years, magnesium slag has been used as a raw material for solid waste treatment using the carbonization method and has proven to be promising in reducing carbon emissions. In this study, the alkali activation reaction was introduced to promote the carbonization of magnesium slag. The resulting mechanical properties, microstructural attributes, and carbonization mechanism were studied by varying the sodium hydroxide content, temperature, and carbon dioxide concentration during the reaction process. The results showed that the amounts of calcium hydroxide, C-S-H, and calcium carbonate in the reaction products increased with the sodium hydroxide content, which enhanced the compressive strength of the composite. However, it does not influence the carbonization mechanism with the increasing reaction temperature, which only elevates the reaction rate. With the increase in the carbon dioxide concentration during alkali activation, the carbonization reaction is dominated by the amount of CO2 dissolved in the reaction medium, and the carbonization mechanism is changed. Thus, a significant decrease in the calcium hydroxide content and a sharp increase in the calcium carbonate content in the products occurred, which significantly improved the compressive strength of the resulting magnesium slag composite. Among them, the maximum compressive strength is 6.83 MPa. [ABSTRACT FROM AUTHOR]

3Cat-4 is the fourth member of the CubeSat series of UPC's NanoSat Lab, and it was selected by the ESA Academy's Fly Your Satellite! program in 2017. This mission aims at demonstrating the capabilities of nano-satellites, and in particular those based in the 1-Unit CubeSat standard, for challenging Earth Observation (EO) using Global Navigation Satellite System-Reflectometry (GNSS-R) and L-band microwave radiometry, as well as for Automatic Identification Systems (AIS). The following study presents the results of the thermal analysis carried out for this mission, evaluating different scenarios, including the most critical cases at both high and low temperatures. The results consider different albedos and orbital parameters in order to establish the optimal temperatures to achieve the best mission performance within the nominal temperatures, and in all operational modes of the satellite. Simulation results are included considering the thermal performance of other materials, such as Kapton, as well as the redesign of the optical properties of the satellite's solar panels. The correlation with the thermal model and the TVAC test campaign was conducted at the ESA ESEC-GALAXIA facilities in Belgium. [ABSTRACT FROM AUTHOR]

Hydrogen is increasingly recognized as a clean and reliable energy vector for decarbonization in the future. In the marine sector, marine solid oxide fuel cells (SOFCs) that employ hydrogen as an energy source have already been developed. In this study, a multi-channel plate-anode-loaded SOFC was taken as the research object. A three-dimensional steady-state computational fluid dynamics (CFD) model for anode-supported SOFC was established, which is based on the mass conservation, energy conservation, momentum conservation, electrochemical reactions, and charge transport equations, including detailed geometric shapes, model boundary condition settings, and the numerical methods employed. The polarization curves calculated from the numerical simulation were compared with experimental results from the literature to verify the model's accuracy. The curved model was applied by enlarging the flow channels or adding blocks. Numerical calculations were employed to obtain the current density, temperature distribution, and component concentration distribution under the operating conditions of the SOFC. Subsequently, the distribution patterns of various physical parameters during the SOFC operation were analyzed. Compared to the classical model, the temperature of the curved model was reduced by 1.3%, and the velocities of the cathode and anode were increased by 4.9% and 5.0%, respectively, with a 2.42% enhancement in performance. The findings of this study provide robust support for research into and the application of marine SOFCs, and offer they insights into how we may achieving "dual carbon" goals. [ABSTRACT FROM AUTHOR]

Ceramic dental restorative materials have growing popularity, albeit their brittle and stochastic nature are acknowledged shortcomings that impact the prosthesis lifespan. The mechanical performance of ceramics is dominated by the constitutional microstructural and fracture toughness mechanisms, as well as externally applied triggers. Thus, there is ongoing expanding research in the sphere of ceramic material engineering and thermal refinement, addressing concerns regarding toughness, machinability, reliability, stainability, and biodegradation. While the current trend in dental ceramic manufacturing has transitioned from micrometric crystalline sizes to submicrometric and nanometric ranges, there is an unclear understanding of the microstructural implications on ceramic behaviour. Therefore, this review covers the comprehensive characterisation approaches commonly employed in the scientific literature to describe the multifaceted performance aspects as well as clinical-related prerequisites of dental ceramics. Moreover, updated standardised testing parameters and performance thresholds pertaining to ceramic mannerisms are described in an attempt to translate their clinical applicability. [ABSTRACT FROM AUTHOR]