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Aiming at the development of thermal environmental barrier coatings (TEBCs) material, the factor of grain size is introduced into the high-entropy rare-earth disilicate for the first time. The (Yb 0.2 Tm 0.2 Lu 0.2 Sc 0.2 Er 0.2) 2 Si 2 O 7 with smaller grain size was prepared by one-step pressureless sintering method. Results of thermal conductivity and coefficient of thermal expansion (CTE) reveal that thermal conductivity of (Yb 0.2 Tm 0.2 Lu 0.2 Sc 0.2 Er 0.2) 2 Si 2 O 7 bulk material is lower than that all existing EBCs and even most TBCs and potential TEBCs material, which is 0.686 W m−1 °C−1 at 1300 °C. Excellent thermophysical properties indicate that designed (Yb 0.2 Tm 0.2 Lu 0.2 Sc 0.2 Er 0.2) 2 Si 2 O 7 with small grain size can be used as a promising TEBCs material. • It is the first time to introduce the grain size into the thermal conductivity of high-entropy rare earth silicate materials. • The prepared (Yb 0.2 Tm 0.2 Lu 0.2 Sc 0.2 Er 0.2) 2 Si 2 O 7 has very low thermal conductivity than all existing EBCs materials. • (Yb 0.2 Tm 0.2 Lu 0.2 Sc 0.2 Er 0.2) 2 Si 2 O 7 with small grain size has excellent thermophysical properties and is a candidate for TEBCs. [ABSTRACT FROM AUTHOR]

• Microencapsulation of PCM with SiO 2 by Sol-gel process. • PCM@SiO2 incorporation effectively reduced concrete pavement surface temperatures, crucial for urban heat management. • Up to 30% PCM@SiO2 replacement maintained concrete strength within Indian standards, suitable for construction use. • Enhanced thermal energy storage capabilities were observed with increased PCM@SiO2 content. This study investigates the potential of enhancing thermal performance in pavement concrete by integrating microencapsulated phase change materials (PCM@SiO 2) using a Sol-gel process for encapsulation. With a concentration range from 0% to 20% in 5% increments, the effects of PCM@SiO 2 on both the mechanical strength and thermal performance of concrete were evaluated. Although the addition of PCM@SiO 2 resulted in a compromise in mechanical strength, significant improvements in thermal performance were observed, demonstrating a promising approach to mitigating temperature stresses and the urban heat island effect in pavement construction. This balance between mechanical and thermal properties underscores the potential of PCM incorporation as a strategic material choice for innovative urban development. [ABSTRACT FROM AUTHOR]

The use of bio-based building materials is a sustainable opportunity to reduce the environmental footprint associated with the construction sector. The achievement of this objective is primely achieved through the valorisation of vegetable waste, resulting in a reduction in the use of primary source material and waste generation. Within the scope of this study, the focus is directed towards research concerning the thermal, acoustic, and fire behaviour properties of bio-based building materials. This study conducts a comprehensive bibliometric analysis encompassing all documents meeting these criteria within the Scopus database, spanning two decades, from 2003 to 2023. The comprehensive analysis covered a total of 1081 documents, which were analysed. This analysis furnishes insight into various facets, including the temporal evolution of publications, journals boasting the highest publication counts and impact, influential research areas, countries with substantial contributions and their collaborative patterns, noteworthy affiliations, prolific authors, and seminal documents, alongside recurrent keywords. The objective of this comprehensive study is to provide a detailed analysis of the documents published up to the present day, in order to identify research gaps and potential opportunities in this field, to assist new researchers interested in the subject. The analysis reveals that bio-based building materials have gained substantial attention over the past decade. With each passing year, the published documents have increased their impact and become more specific, underscoring the growing importance of this subject. This evolution has also fostered a broader network of researchers engaged in this field. However, it is noteworthy that the characterization of these materials focuses predominantly on their thermal properties, while research avenues related to acoustic and fire properties remain less explored and present opportunities for future investigation. • This study contributes to identify research gaps and potential opportunities in the field of bio-based building materials. • Studies in bio-based building materials have shown an annual growth of the 25% since 2014, being a topic on the rise. • France and China are the countries with the highest scientific publication on bio-based building materials. • Keywords play a crucial role in making visible the research within bio-based building materials. • "Thermal Conductivity" and "Thermal insulation" are the most repeated keywords in this field. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mn-based oxides were acquired by calcining the precursors of MnCl 2.4H 2 O, MnCO 3 , MnO 2 , and KMnO 4. • The phase formation was influenced by the temperatures (400–1000 °C) and precursors. • The obtained phases were analyzed for their thermal and spectroscopic properties. • The nanostone was seen in the form of Mn 3 O 4 , while the nanorod-like shape was observed in Mn 2 O 3. • The Mn 3 O 4 phase exhibited a high NIR reflectance of 68 % in the solar region and 91 % in the color region. We examined how different calcination temperatures and precursors affect the formation of Mn-based oxides. The formation of these oxides was influenced by both the temperature (400–––1000 °C) and the type of precursors used (MnCl 2 ·4H 2 O, MnCO 3 , MnO 2 , and KMnO 4). When MnCl 2 ·4H 2 O was calcined at 800 and 1000 °C/3h, we obtained pure tetragonal Mn 3 O 4 phase materials. Calcining MnCO 3 at 600 and 1000 °C resulted in cubic Mn 2 O 3 and tetragonal Mn 3 O 4 phase materials, respectively. Heating commercial MnO 2 powder at 600 and 800 °C transformed it into cubic Mn 2 O 3 phase materials. At 400 °C, the tetragonal MnO 2 phase remained, but at 1000 °C, mixed Mn 3 O 4 and Mn 2 O 3 phases formed. Calcining KMnO 4 at 1000 °C/3h led to the formation of δ-MnO 2 materials. The morphological features of Mn 2 O 3 and Mn 3 O 4 materials exhibited different sizes and shapes, including nanostone-like, nanorod-like, and nanoflakes morphologies. The thermal analysis revealed significant differences in weight loss and thermal events, including exo and endothermic peaks. The Raman spectra and UV–Vis DRS measurements data support the formation of Mn-based oxides. The highest NIR reflectance for the various synthesized materials of Mn 3 O 4 phase indicates a reflectance of 68 % in the solar region and 91 % in the color pigment region. [ABSTRACT FROM AUTHOR]

• Two cyclophosphazenes with nitrophenole substitutients were synthesiszed, characterized, and structurally studied by x-ray crystallography. • Two new denderimers exhibited good antibacterial and anticancer activities. • The thermal behavior of two denderimers was investigated by thermogravimetric analysis (TGA), and differential thermal analysis. • Nitrophenolic substitutents quenched the fluorescence of phosphszene ring. This study introduces the synthesis and characterization of two novel nitrophenol-substituted phosphazene dendrimers, [N 3 P 3 (OC 6 H 5 NO 2) 6 ] (III) and [N 3 P 3 (OC 6 H 5 (NO 2) 2) 5 O]ˉ.C 6 H 16 N+.H 2 O (IV), derived from hexachlorocyclotriphosphazene (HCCP). The structures of the compounds were determined using elemental analysis, infrared spectroscopy, and X-ray crystallography. The optical properties of the crystals were investigated by photophysical methods. The thermal properties of the compounds were measured by thermogravimetry-differential thermal analysis (TG-DTA). The antibacterial and anticancer properties of the compounds were tested based on the antibacterial tests against Gram-negative (Escherichia coli ATCC 8739 G(-)) and Gram-positive (Staphylococcus aureus ATCC 6538 G(+), Bacillus subtilis 2a ATCC 23,857 G(+)) bacteria, as well as the MTT assay test on K562 leukemia cells (ATCC: CCL-243) and MCF-7 breast cancer cells (ATCC: HTB-22). The presence of six homogeneous 2-nitrophenol substitutions in compound III reduces the fluorescence of the phosphazene ring. The results showed that compound IV has a higher fluorescence intensity and similar toxicity to MCF-7 and HDF cells. The structural differences and the number of nitro groups in the nitrophenol ligands account for these variations. Our results suggest that these cyclophosphazene derivatives have promising properties for biomedical applications and further studies are warranted to explore their mechanisms of action and therapeutic potential. [ABSTRACT FROM AUTHOR]

Carbide dispersion for reinforcement is an effective strategy to enhance the performance of tungsten (W). High-entropy carbides (HECs), when compared to conventional carbides, offer superior thermal stability, hardness, mechanical strength, creep resistance, and wear resistance. This study represents the first successful incorporation of (HfNbTaZr)C as a reinforcing phase into a W matrix, resulting in the formation of a W-HEC alloy. Compared to other carbides such as ZrC, HEC demonstrates improved coherency with the W matrix, resulting in a significant increase in plasticity and enhanced high-temperature stability. This innovative approach paves the way for alloy design in high-temperature applications such as nuclear fusion, providing fresh insights into the enhancement of mechanical properties and thermal stability. • A (HfNbTaZr)C HEC has been synthesized, for the first time, incorporated as a reinforcing phase into the W matrix. • The mismatch between HEC(200) and W(110) is 0.018, smaller than the W-ZrC alloy, indicating better coherence with the W matrix. • The W-HEC demonstrates outstanding plasticity at 600 °C, displaying total elongation of 33.0%, surpassing other W alloys. • The W-HEC hardness decreases is less than the W-ZrC after annealing at 1800 °C, demonstrating superior thermal stability. [ABSTRACT FROM AUTHOR]

Pressurized liquid extraction (PLE) is an emerging eco-friendly approach for recovering protein from broken black beans (BBB). This investigation explored the thermal and structural characteristics of BBB protein fractions recovered via PLE compared to the emerging technologies of ultrasound- and microwave-assisted extractions (UAE and MAE) and conventional heating-stirring extraction (HSE) using water and alkaline water (pH 9.0) as solvents. Alkaline water extractions exhibited superior protein yields and purity, resulting in protein aggregates of smaller sizes (<150 nm) in the BBB protein concentrates recovered by PLE and UAE. In comparison, larger aggregates of protein flour were formed when applying HSE (>450 nm), regardless of the solvent used. Nevertheless, heightened pH levels induced substantial modifications in protein conformation, reducing the denaturation temperature (T d) and enthalpy. β-strands and random coil conformations dominated the secondary structure, while α-helix was solely observed in alkaline PLE. The selection of the extraction technique had a pronounced influence on protein partial unfolding, leading to diverse protein profiles and properties. PLE (water) presented a viable and eco-friendly alternative for attaining protein recovery with high purity (86.7%) and thermal stability (T d : 78.7 °C, enthalpy: 207.20 J/g). BBB protein research advancements offer opportunities for sustainable and nutritious plant-based protein sources with global economic and social benefits. [Display omitted] • Alkaline water extraction enhances BBB protein yield. • Extraction technique influences protein unfolding and thermal stability. • Increased pH induces conformational changes in the protein, reducing T d and ΔH. • β-sheet and random coil dominate BBB protein structure; PLE (alkaline) shows α-helix. • PLE (water) provides eco-friendly protein recovery with high thermal stability. [ABSTRACT FROM AUTHOR]

[Display omitted] • A hydrophobic Pba and a hydrophilic glycomonomer were polymerized. • The polymerization gave the corresponding water-soluble glycopolymer having Pba moieties. • Structural elucidation of the polymer was performed by 1H NMR. • The thermal property of the polymers was evaluated on the basis of TG-DTA measurement. • Uv–vis spectroscopic analysis of the polymer showed the characteristic absorption due to Pba. The first trial of incorporation of pheophorbide a (Pba) into a synthetic glycopolymer giving water-soluble ability was carried out, and the polymerization reaction of each monomer proceeded in DMSO to afford the desired glycopolymer having Pba side chains. Characterization of the polymer was performed by means of spectroscopic analyses and thermal studies, and the results supported the desired macromolecular architecture. [ABSTRACT FROM AUTHOR]

La(Fe,Si) 13 alloys are prone to display burst-like phenomena at their first-order ferromagnetic transition, such as a latent heat decomposed into a succession of heat flux avalanches. For some extreme cases, these phenomena are so pronounced that they can yield recalescence/antirecalescence events. It turns out that these features are also highly sensitive to the technical specificities of the employed measurement systems. Here, we compare the thermal events at the first-order magnetic transition of LaFe 11.4 Si 1.31 Co 0.29 using magnetization, two differential scanning calorimeters and a thermometry probe specially designed for the present study. These techniques are complementary to each other, and allow to make a distinction between the properties influenced by thermal coupling and those more intrinsic to the compound or to the sample. A simple thermal model is built to account for the thermal lags in the different devices, and to provide insights into the dependence of the duration of the transition on the thermal sweep rate. Looking in closer detail at the development of the transition, we found evidence of a rate independent initial regime, followed by a second one along which the same shape of temporal profile is spread over a more or less long duration depending on the sweep rate. Possible underlying mechanisms corresponding to these regimes are discussed. [Display omitted] • Comparative study including rarely considered Tzero DSC and thermometry probes. • A thermal model describes the complex dependency of transition duration on sweeping rate. • Detailed thermometry measurements confirm the reproducibility of the transition path. • A rate independent initial regime is observed from DSCs and thermometry measurements. [ABSTRACT FROM AUTHOR]

In this study, the effects of Ca addition on the microstructure, thermal properties, and mechanical properties of a Mg-6.0Zn-1.2Y-0.7Zr (ZWK611) alloy at room temperature and 150 °C were investigated. With an increase in the Ca content, the ignition resistance of the ZWK611 alloy improved and the grains became finer. The as-cast ZWK611 alloy consisted mainly of the dendritic α-Mg matrix and I-phase (Mg 3 Zn 6 Y) at the grain boundaries. On the other hand, the τ- (Ca 2 Mg 6 Zn 3) and I-phases were formed in the Ca-added ZWK611 alloy. The fraction of the τ-phase increased with an increase in the Ca content. After the solid-solution treatment, these phases remained partially at the grain boundaries of the Ca-added ZWK611 alloys and an additional W-phase (Mg 3 Zn 3 Y) was observed. The phases remaining at the grain boundaries restricted the grain growth through the grain boundary pinning effect. The aging treatment resulted in the formation of MgZn' precipitates in the α-Mg matrix of the alloys. These precipitates were more uniformly distributed in the Ca-added alloys than in the alloys without Ca. Thus, the heat treatment-induced precipitation improved the tensile and creep properties of the T6-treated alloys. The T6-treated ZWK611+0.7Ca alloy exhibited the best mechanical properties at room temperature and 150 °C among all the tested alloys. [ABSTRACT FROM AUTHOR]

• Based on the SDC-IC standard, a integral analysis of thermal mechanical properties was conducted using a combination of elastic and plastic analysis methods • In ductile damage analysis, local plastic yielding occurs in the inner tube, but the overall load-bearing performance of the structure is good. • In non-ductile damage analysis, the T-tube unit have the immediate plastic flow localization, but there is no the immediate local fracture due to exhaustion. • From the perspective of transient cyclic thermal hydraulic analysis, the results show that there will be no ratcheting. To verify the mechanical properties of the helium-cooled T-tube divertor, based on the thermal hydraulic optimization of the T-tube divertor, a preliminary analysis was conducted through a combination of elastic and elasto-plastic analysis. The results show that for the M-type damage mode, the T-tube divertor exhibits a small-scale plastic yielding phenomenon, but this has no effect on the overall divertor. The T-tube divertor has local necking deformation but does not fail due to immediate local fracture, and the T-tube divertor has no creep rupture. For the C-type damage mode, the plastic strain of the T-tube divertor is not accumulated under cyclic loading, but in the fatigue analysis, the life of the divertor does not meet the design standards and further optimization is needed. The conclusion shows that the optimized helium-cooled T-tube divertor has good thermo-mechanical properties, and the safety of the helium-cooled T-tube divertor unit can be guaranteed. [ABSTRACT FROM AUTHOR]

• Analytical evaluation of TRTs influenced by groundwater flow. • More physically correct results and 43–77 % better fits to measurement data obtained. • Cheap and simple alternative to cumbersome, expensive modelling. • Groundwater flow quantification from TRT results. Proper design of larger ground source heat pump installations, and borehole thermal energy storages (BTES) requires determination of on-site thermal properties of the ground by performing a thermal response test (TRT). The effective thermal conductivity is an important design parameter from TRT that is determined from the line source equation. The line source equation does not include advection and may give incorrect results when groundwater flow is present. This study describes the development and application of a new analytical equation where advective heat in fractured, nonporous rock is accounted for. Including advective heat improves the fit to the measurement data (1.2–77 % better) when applying reasonable values for the thermal conductivity of the ground. The new analytical equation is applicable to all TRTs. Previous studies recommend comprehensive numerical modelling of boreholes affected by groundwater flow. The equation proposed here is an analytical alternative which does not require modelling and is a recommended and cost-effective alternative when groundwater flow affects the thermal properties measured in a borehole heat exchanger in fractured rock. [ABSTRACT FROM AUTHOR]

In contemporary developments across automotive, aerospace, and military industries, there is an ever-growing demand for lightweight and robust polymer composites. In this study, a ductile epoxy resin, carbon nanotubes (CNTs), cellulose nanofibers (CNFs), and silica nanoparticles were used to fabricate nano-fillers/epoxy composites and nano-fillers/silk fibers/epoxy hybrid composites through solution casting and hot pressing. Their mechanical properties and thermal characteristics were analyzed and compared, which show that: these nano-fillers can dramatically enhance the strength and stiffness of the ductile epoxy resin; however, this is achieved at the expense of its toughness and extensibility. CNT/silk fiber/epoxy hybrid composite has the highest tensile strength (81.10 MPa), Young's modulus (3.76 GPa) and impact strength (103.7 kJ/m2), while the CNFs-reinforced one exhibits the highest breaking energy (9.96 MJ/m3). These nano-fillers almost do not affect the thermal stability of the epoxy resin and silk fiber composites. In addition, the fracture modes of their reinforced composites were revealed by macroscopic and microscopic observations. • Reveal how different nano-fillers affect the mechanical behaviors of ductile polymer matrix. • Explore the optimal content of these nano-fillers in the polymer matrix. • Indicate nano-fillers do not affect the thermal stability of their reinforced composites. • Elucidate the composites' fracture modes introduced by silk fibers and different nano-fillers. [ABSTRACT FROM AUTHOR]

The development of high-power and small-sized electronic components requires the emergence of heat management materials with high heat flux. Hence, Ti-containing filler was used to braze graphite film/Cu high heat flux composites. The microstructure and forming mechanism of joints were studied, the influence of temperature on joint formation was analyzed, and the influence of graphite volume fraction on the thermal properties of the composites were discussed. The results show that the main microstructure of graphite/copper joints are Cu(s,s), Ti 6 Sn 5 and CuTi 2. As the brazing temperature increases, the carbide layer (TiC) that affects the connection gradually thickens, from <0.5 μm at 800 °C to 3 μm at 850 °C, which deeply improve heat transfer of composite materials. The tensile properties of composites also increase with increasing temperature, maximum tensile strength 31.94 MPa can be obtained at 850 °C. Furthermore, the composites are proved to possess high heat flux during process of heat transfer, and the transfer rate was 1.77 times that of Cu, 3.72 times of Al. The temperature rise test carry out in hot bench intuitively demonstrating that the composites have faster heating rate. Al used 197 s to raise from 25 °C to 50.5 °C, Cu used 140 s, while 76.92 % graphite-contained composites only took 75 s in the same volume and experimental condition. [Display omitted] [ABSTRACT FROM AUTHOR]

Thermal protection and power generation are two of the major technical challenges in developing hypersonic vehicles with long-range/endurance. This research is aimed to provide a system for thermal protection and power generation for hydrocarbon-fueled scramjets. This study proposed a thermal management system based on fuel vapor turbine (FVT) and closed-Brayton-cycle (CBC) to generate power, and a bypass loop is connected with CBC in parallel to ensure thermal protection demand. A performance analysis model considering the combustor and cooling channels is established. The combustion and heat transfer process are described in a quasi-one-dimensional way, while FVT and CBC are described in a zero-dimensional form. Results indicate that large CBC power generation efficiency (η PG,CBC) and FVT expansion ratio (π FVT) can improve power generation with the same thermal protection performance. Because of the integrated variation law of cooling heat exchange and η PG,CBC , there exists an optimal value of fuel outlet temperature (T f 3) while meeting the thermal protection requirement. The high Mach number and low equivalence ratio both require a significant increase in the cooling capability of fuel, and it is feasible to sacrifice the power generation of the CBC subsystem to meet the thermal protection demand. • A thermal management system is proposed for hydrocarbon-fueled scramjets. • A model considering the combustion process and the heat transfer process is established. • There is an optimal value of T f 3 while meeting the thermal protection requirement. • It is feasible to sacrifice the CBC subsystem power generation to meet thermal protection demand. [ABSTRACT FROM AUTHOR]

[Display omitted] • Plastic pollution contributed mostly from packaging industry seeks a solution in eco-friendly alternatives. • Natural fiber composites could cater to versatile demands posed by carry bags. • Indigenous fibers like coir, cotton are used as hybrid reinforcement dispersed in recycled paper matrix. • Mechanical tests reveal better tensile, impact and water repellent properties over standard packaging paper. • Thermal analysis was carried out to shimmer light on thermal stability of the novel material. Increasing concern about environmental pollution has led researchers to find sustainable alternatives to synthetic counterparts. With the packaging industry accounting for 42 percent of plastics entering our marine systems, governments have also passed legislation banning single-use plastics. This paper essays the fabrication and experimental validation of hybrid bio composite with coir and cotton fiber reinforcement dispersed in paper matrix. Specimen with varying concentration of coir and different fiber length was validated against 150 GSM standard packaging paper material. The specimen constituted by 20 wt% coir was observed to have better tensile strength of 2.678 N/mm2, Izod higher impact value of 0.15 J compared to the standard sample which had tensile strength of 1.875 N/mm2 and lower Izod impact value of 0.10 J. Increasing coir content led to 142.4% higher water absorption and was not appreciable for making carry bags. The thermal stability characteristics of composite specimens were comparable to conventional packaging materials. [ABSTRACT FROM AUTHOR]

Glass system, with the following chemical composition xCuO∙(100-x)PbO 2 where x = 0, 5, 8, 10, 15, 20 mol% CuO, was successfully prepared using the melt-quenching technique. X-ray diffraction pattern indicated the amorphous structure for all samples. Density and molar volume were determined to evaluate the physical properties of the glasses. The evolution of the endothermic and exothermic process as CuO function was investigated by thermal analyses. The structural modifications induced by the incorporation of CuO in the lead host network were investigated by Fourier Transform Infrared, Raman, Ultraviolet-Visible and Electron paramagnetic resonance. The obtained results depicted the incorporation of Cu2+ ion enhances thermal stability and glass-forming ability of the lead glass. Furthermore, X-ray diffraction, Scanning electron microscopy and energy dispersive X-ray analysis confirm high solubility of MoO 3 in copper-lead host matrix. It was found that copper-lead dioxide host matrix is a suitable as waste form for radioactive waste management applications to improve the solubility of MoO 3 in glass. • Novel heavy metal oxide (HMO) glass composition for nuclear waste management applications. • xCuO∙(100-x)PbO 2 where x = 0, 5, 8, 10, 15, 20 mol% CuO system was synthesized by melt-quenching method. • FTIR spectra exhibit the coexistence of the basic structural units of lead [PbOn] and [CuO n ]. • UV–VIS absorption bands and EPR spectra indicated the presence of isolate Cu2+ ions. • High solubility of MoO 3 in copper-lead glass, without any phase separation. [ABSTRACT FROM AUTHOR]

• Ionic surfactant was successfully studied upon experimental and theoretical analysis. • All spectroscopic data were confirmed with DFT- B3LYP /6311G++(d, p) computation. • Molecular structure was optimized and compared to the experimental asymmetric unit. • Thermal properties were investigated theoretically and experimentally. • Antibacterial tests demonstrated an excellent activity and a mechanism was proposed. The present study investigates the properties of benzethonium chloride compound using experimental analysis (NMR, FT-Raman/FTIR, TGA/DTG and DSC) and DFT method. Three molecular structures (BZT, BZT-Cl and BZT-Cl-H 2 O) were considered and optimized using 6–311++ G ** method. The computed theoretical shifts depicted an excellent matching with 13C and 1HNMR peaks, as well for FT-Raman and FTIR spectroscopic data. On the other hand, it was found that BZT-Cl compound has a higher polarizability (α) along z-direction when compared to BZT and BZT-Cl-H 2 O; while adding of chlorine and water molecule increase significantly the total first-order hyper-polarizability (β). The electrostatic mapping potential depicted that chlorine and water enhanced the nucleophile character. The HOMO-LUMO energies and reactivity parameters significantly change in BZT-Cl and BZT-Cl-H 2 O. Furthermore, the thermal analysis showed a good stability up to 160 °C. Finally, antibacterial tests against several strains demonstrated an excellent activity and a mechanism structure/activity was proposed. [ABSTRACT FROM AUTHOR]

A new series of cobalt-based perovskite (Gd 0.6 Sr 0.4) 0.99 Fe 1-x Co x O 3-δ (GSFC-x, x = 0.00, 0.05, 0.10, 0.15, 0.20 and 0.25) cathodes to aid in the development of intermediate temperature solid oxide fuel cells are reported. All the perovskites showed the coexistence of cubic and orthorhombic phases. To determine their suitability, the thermal properties dependence on the cobalt content were investigated via dilatometry, thermogravimetry and differential scanning calorimetry. GSFC-x exhibited the promising activity of the oxygen reduction reaction and ion transport from a comparable study. The thermal expansion coefficient of rich-cobalt samples showed a more compatible value to the common electrolyte than other similar cathodes. By varying Co doping, compromises were made between thermal expansion and electrical conductivity. Furthermore, phase stability was observed. [ABSTRACT FROM AUTHOR]

This paper proposes an integrated photovoltaic vacuum glazing unit with an intermediate air cavity and a calibrated modelling approach to quantify its thermal properties and evaluate the heat transfer performance. Theoretical analyses of the heat transfer process are conducted with reasonable hypotheses and traceable boundary conditions. Three-dimensional heat transfer models are then established and cross-validated against previous publications. The detailed validation demonstrates the reliability of the developed complex models under different circumstances. Furthermore, four photovoltaic vacuum glazing configurations are compared in terms of the temperature distribution and overall heat transfer coefficient (i.e. U-value). Simulation results show that the photovoltaic vacuum double glazing can achieve the optimum performance among the four configurations based on simultaneous consideration of the PV module temperature and U-value. Sensitivity analyses of glazing design factors are also conducted for the U-value, which is found to be greatly reduced by decreasing the density and diameter of vacuum pillars as well as the glass thermal conductivity. A lowest U-value of 0.23 W/(m2·K) is achieved for the photovoltaic-vacuum double glazing and can be further improved with future design optimizations. This research can provide guidance to design improvement of PV vacuum glazing systems and promote their integration with building modelling tools. • A 3D heat transfer model of PV vacuum glazing is established and cross-validated. • Four compositive PV vacuum glazing configurations are proposed and compared. • The intermediate air cavity can reduce the U-value of PV vacuum glazing by 25%. • The PV vacuum glazing can achieve a U-value of 0.23 W/(m2·K). • Sensitivity analysis can provide a design guideline for PV vacuum glazing. [ABSTRACT FROM AUTHOR]

This work investigates the extraction of cellulose nanocrystals (CNC) from bamboo fibre as an alternative approach to utilize the waste bamboo fibre. In this study, bamboo fibre was subjected to acid hydrolysis for efficient isolation of CNC from bamboo fibre. The extracted CNC's were morphologically, characterized via Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM) and Atomic Force Microscopy (AFM). The energy Dispersive X-rays (EDX) provided the elemental composition of the prepared CNC's and X-ray diffractometer (XRD) exhibited their crystallinity. The physiochemical analysis was done via Fourier Transform Infrared (FTIR); and their thermal analysis was revealed by Thermogravimetric Analysis (TGA) and Differential scanning calorimetry (DSC). As from their morphological investigations, rod like structures of CNC's were observed under SEM analysis with higher carbon content as demonstrated by EDX, while needle shaped CNC's were observed from TEM and AFM studies. Acid hydrolysis for 45 min resulted into higher degree of crystallinity and higher yield of CNC's about 86.96% and 22% respectively. Owing to higher quality of CNC's obtained as a result of efficient and modified techniques, these can find potential usage in nanocomposites for biomedical and food packaging application. • Nanocrystalline cellulose (NCC) was extracted from bamboo fibre by acid hydrolysis. • Acid hydrolysis followed by ultrasonification to get highly crystalline cellulose • Disintegrated rod structured NCC evidenced the effectiveness of the technique. • The NCC of higher thermal stability were obtained from bamboo. [ABSTRACT FROM AUTHOR]

In the present work, silver nanoparticles (AgNPs) are generated using the Micro-Electro Discharge Machining process (micro-EDM). Nanofluids are synthesised in dielectric fluids such as polar fluid like Deionized water (DI), Deionized water with 4 wt% of Poly-Vinyl Alcohol (DI + PVA), and non-polar fluids like Ethylene Glycol (EG) and Kerosene (KR). Low energy consumption, in-situ nanofluid synthesis, cleaner work environment, non-essential chemical post-processing during the synthesis using micro-EDM are the significant reasons creating broad scope for this process exploration. To understand the process, theoretical approach is explored to study the effect of dielectric fluids on particle formation mechanism, critical radius and nucleation rate of nanoparticles. In the experimental approach, silver nanoparticles are generated and characterized for the particle concentration, morphology and size distributions in all four dielectric fluids. High Resolution Scanning Electron Microscopy (HRSEM), Dynamic Light Scattering (DLS), and UV–Visible spectroscopy (UV–Vis) are used for the study. Nanofluid's decomposition temperatures and latent heat of vaporization are investigated using ThermoGravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC), respectively. Particles generated in DI + PVA fluid found to be smaller mean size of (30.06 ± 1.12) nm followed KR fluid of (40.32 ± 1.29) nm, EG fluid of (47.85 ± 1.24) nm, and in DI fluid of (149.04 ± 1.93) nm. Also polar liquids yielded wider and non-polar liquids yielded narrower particle distribution. KR nanofluid is thermally stable followed by DI + PVA, DI, and EG nanofluid. With the spark energy of 1.15 mJ, the in-house developed micro-EDM process yielded highest nanoparticles concentration of 2.68 g/L in KR fluid followed by DI + PVA fluid of 2.13 g/L, DI fluid of 2.09 g/L and least by EG fluid of 1.04 g/L. [ABSTRACT FROM AUTHOR]

To further investigate the reinforcing factors on the adhesion strength of SiO 2 and TiB 2 modified SiBCN-based adhesives, the thermal stability analysis, microstructure observations and phase composition analysis were performed on four kinds of modified PSNB (Polyborosilazane) adhesives. With the different Si/B ratio and SiO 2 content, the room temperature adhesion strength reach up to 18.95, 12.04, 32.44 and 13.69 MPa for PPT-1, PPT-2, PPTS and PST respectively, after synthesized at 1000 °C in air. And then, the high temperature adhesion strength reach up to 12.3 and 16.4 MPa for PPT-1 and PPTS at 1000 °C in vacuum, respectively. Interestingly, it has been found that temperature, PSO, solid content and SiO 2 content all have a great influence on the adhesion performance of SiO 2 and TiB 2 modified SiBCN-based adhesives. [ABSTRACT FROM AUTHOR]

The starch nanoparticles from water chestnut (WS), lotus stem (LS) and horse chestnut (HS) starch were synthesized using planetary ball milling. The starch nanoparticles were investigated by using various techniques like particle size analyser, differential scanning colorimeter (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM), rheometer, and attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR). The particle size of horse chestnut starch nanoparticles (HNS), water chestnut starch nanoparticles (WNS) and lotus stem starch nanoparticles (LNS) was found to be 343,271 & 855 nm with zeta potential of −18.75, −20.45 & −12.2 mV, respectively. SEM revealed small and damaged starch granules. The relative crystallinity was decreased from 13.13 to 6.22, 22.27 to 7.96 and 26.16 to 7.98% in HS, LS and WS starch after ball milling and average crystallite size of starch nanoparticles was found to be 9–12 nm. The starch nanoparticles also showed increase in transition temperature and viscosity as analysed by DSC and rheometer, respectively. These properties could be useful in particular food and drug formulations. [ABSTRACT FROM AUTHOR]

Hydrated salt of aluminium potassium sulfate dodecahydrate (APSD)/expanded graphite (EG) form-stable composite phase change material (PCM) has been prepared. Hydrated salt of aluminium potassium sulfate dodecahydrate used as the PCM was firstly modified by using nucleator and thickener with the aiming at solving the supercooling and phase separation. Sulfurized EG is selected as supporting matrix to overcome leakage and low thermal conductivity of MAPSD. Furthermore, hydrophilic and hydrophobic groups on the surface of the expanded graphite is oriented by carrying out titanate coupling agent, which could restrict the volatilization of crystal water and solve the poor cyclic stability problems of APSD. The thermal performance of modified APSD (MAPSD) and modified EG (MEG)/MAPSD composite PCMs are tested and analyzed by using Differential Scanning Calorimeter (DSC), Hot Disk Thermal Constant Analyzer and a small-scale experimental device. The DSC analysis showed that the melting enthalpy of form-stable composite PCM containing 80 wt% APSD and MAPSD are 473.52 and 641.75 J/g, and their corresponding melting points are 84.39 and 84.34 °C, respectively. The 100 times melt-freeze cyclic tests revealed that the mass of MAPSD decreases by 45.57%. However, the mass of MEG/MAPSD composite PCMs decreases by only 7.91% when the sample density (ρ) of 900 kg/m3 and mass fraction of MEG with 20%, which could still maintain its original shape perfectly without any change. What's more, the effective thermal conductivity of MEG/MAPSD composite PCM (6.157 W/(m·K)) is about 11 times higher than that of pure APSD (0.55 W/(m·K)) and Agari-Uno model is used to predict the thermal conductivity of composite PCMs with different MEG contents. The average deviation is only 3.91% between experimental and predicted value. All the results indicate that the form-stable MAPSD/MEG composite PCMs can be considered as high-performance latent heat storage materials and the great potential for practical application in solar thermal utilization. • A novel MEG/MAPSD form-stable composite PCM is prepared. • The composite PCM has good thermal storage capacity and cyclic stability. • Thermal conductivity reaches as high as 6.157 W/(m·K). • The average deviation is only 3.91% between experimental and predicted values. [ABSTRACT FROM AUTHOR]

This work aimed to characterize the fuel properties and to evaluate the kinetics of thermal decomposition of defective coffee beans (DCB). Three thermogravimetric-based methods were evaluated: Ozawa-Flynn-Wall (OFW), Kissinger-Akahira-Sunose (KAS) and Friedman. The results showed that DCB presented low activation energy and that the evaluated mathematical models, although satisfactory for describing thermal decomposition in inert atmospheres, did not provide a satisfactory description of the oxidizing process. The enthalpy values indicated that the energy differences between the reagents and the activated complex are related directly to the activation energies. Pre-exponential factors indicated first-order reactions. The immediate analysis and the lignocellulosic contents indicated a biomass with low levels of humidity and ashes, high carbon and volatile concentrations, besides thermal stability. The obtained calorific value was 19.39 MJ/kg. The overall results obtained in the present study indicate that this biomass has the potential to be used as a solid biofuel. • Fuel properties and thermal decomposition kinetics of defective coffee beans (DCB). • DCB has low levels of humidity and ashes, high carbon and volatile concentrations. • Material presents thermal stability and calorific value of 19.39 MJ/kg. • Kinetic models provided good description of thermal conversion in inert atmosphere. • Results confirm that this biomass presents potential to be used as a solid biofuel. [ABSTRACT FROM AUTHOR]

The novel exopolysaccharide (EPS-B3-15) produced by the marine thermotolerant Bacillus licheniformis strain B3-15, constituted by mannose and glucose, has been recently reported as a valuable biopolymer in pharmaceutical applications. To dynamically characterize the thermal behavior of the whole EPS-B3-15 system, the Attenuated Total Reflectance Fourier Transform Infra-Red spectroscopy technique was used over a temperature range from ambient to 78.5 °C. The molecular changes of EPS-B3-15 during the heating process were evaluated by the spectral distance (SD) and wavelet cross-correlation (XWT) analysis. The thermal analysis revealed that the EPS-B3-15 possessed high stability until 78.5 °C. As evaluated by SD and XWT, the molecular structure of EPS-B3-15 at 45 °C was partially modified, due to –OH groups and the –COOH and –OH interactions, conferring a new conformational structure to the biopolymer. The thermal characterization provides novel information about the molecular conformations of the whole EPS-B3-15 system at different temperatures. The thermostable EPS-B3-15 can be successfully employed for biotechnological, nanotechnological and material science applications even at high temperatures. [ABSTRACT FROM AUTHOR]

The application of boron in fuel-rich solid propellant is limited by its long combustion time, ignition delay and low combustion efficiency. To overcome these problems, B/Nitrocellulose (NC)/Fe particles were fabricated by electrospraying. The reactivity and combustion behavior of B/NC/Fe particles were characterized by TG/DSC, oxygen bomb calorimeter and laser ignition. Compared with pure boron, lower oxidation temperature was observed in the thermal analysis of prepared particles. Meanwhile, the prepared particles released more heat and ignite more readily during the combustion. Furthermore, B/NC/Fe particles were added into Hydroxyl-terminated polybutadiene (HTPB)/Ammonium perchlorate (AP) propellants as additives to test their combustion performance. The burning rate of propellants in air and closed bomb were both improved by 8.20% and 117%, respectively. Overall, B/NC/Fe particles not only show the superior reaction performance, but also contribute to the tunable burning rate of propellants. [ABSTRACT FROM AUTHOR]

The biocomposite systems based on mesoporous MCF silica support and protein molecules are characterized with regard to their surface, topographic, thermal properties. Mesoporous silica materials (MCF) covered by the adsorbed protein molecules (BSA and OVA) were examined and characterized by using various techniques including X-ray diffraction, the Fourier transform infrared spectroscopy with attenuated total reflectance, X-ray photoelectron spectroscopy and scanning electron microscopy with microanalysis. The results of study focused on a detailed analysis of microstructure (topography, texture), and chemistry (chemical bonds, functional groups, elemental composition) of protein/mesoporous silica biocomposite. Moreover, the thermal properties of prepared biomaterials were investigated by means of TG/DSC-FTIR-MS-coupled technique. These powerful methods provided detailed information for understanding protein adsorption on MCF. Significant differentiation in surface chemistry and topography of MCF material was observed after protein adsorption. Basing on the results of thermal analysis stronger changes of the surface properties and more stable interactions of biomolecules with MCF-d16 support were observed for larger BSA molecules compared to smaller ovalbumin ones. Unlabelled Image • Microstructure, textural and thermal properties of the protein/mesoporous silica biocomposite are explored • Significant differentiation in surface chemistry and microstructure of MCF material was observed after protein adsorption • More stable biomolecules interactions with MCF support were observed for larger BSA molecules than smaller ovalbumin ones [ABSTRACT FROM AUTHOR]

Posidonia oceanica brown algae (POBA) represent an abundant and renewable biomass in Algerian seas. In the present study, the POBA were chemically treated through delignification and alkali treatment followed by acid hydrolysis to produce pure microcrystalline cellulose (MCC). FTIR analysis indicates that most lignin and hemicellulose were eliminated during the chemical treatments. The XRD measurements revealed that the obtained cellulose and MCC belong to cellulose I polymorph, with crystallinity index of 60.50% and 74.23%, respectively. SEM micrographs of the produced MCC showed a non-uniform micro sized rod-like shape morphology with an average diameter of 8.4 ± 2.1 μm. The thermal analysis results exhibited that the decomposition temperature of the prepared MCC shifted to higher temperature compared to that of the respective cellulose and raw POBA. The authenticity of the prepared MCC was also examined by comparing its physicochemical properties with those of commercial MCC. Based on these analyses, POBA-MCC showed tremendous potential to be used in several applications. [ABSTRACT FROM AUTHOR]

Hydroxyapatite powder was mixed into photosensitive resin to form complex shape scaffold using SLA-3D printing technology, and then the final entity was obtained successively by debinding and sintering. It is crucial to confirm whether the prepared hydroxyapatite scaffold have the toxic effects after our designed printing, debinding, and sintering processes because the photosensitive resin in the starting printing paste is poisonous to cells. To investigate these issues in details, thermogravimetric analysis (TG), differential scanning calorimetry (DSC), in vitro cytotoxicity test, and implantation pre-experiment in the rabbit parietal were performed, aiming to develop the SLA-3D prepared hydroxyapatite scaffold. Through thermal analysis, it was proved that photosensitive resin would be completely pyrolyzed at temperature ranging from 350 °C to 580 °C, corresponding to a secondary chemical reaction mechanism. Combined with cytotoxicity test results, it is unquestionable that the toxic substances would be totally decomposed after debinding process and a good biocompatible HAP samples could be obtained. The finally prepared HAP samples with micro-holes showed good biosafety in pre-experiment of the rabbit parietal implantation. Image 1 • The HAP sample was fabricated by SLA-3D printing technology successfully. • The pyrolysis properties and kinetics of the photosensitive resin was proposed. • It is proved that final HAP ceramic can be used as biosafety implant. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of novel statistical copolymers of isocyanates. • Synthesis of novel block copolymers of isocyanates. • Improvement of the thermal stability of polyisocyanates. • Mechanism of thermal decomposition of polyisocyanates. • Effect of macromolecular architecture on the thermal stability of polyisocyanates. The synthesis of statistical and block copolymers of n-hexyl isocyanate (HIC) and 2–phenylethyl isocyanate (PEIC), via coordination polymerization using a half-titanocene complex, was studied. The complex [CpTiCl 2 (O-(S)-2-Bu)] was employed as initiator of all the polymerization reactions. The homopolymerization of PEIC was initially attempted under various experimental conditions. The statistical copolymers were synthesized in different proportions of the two monomer units, and their reactivity ratios were estimated using the Fineman-Ross, inverted Fineman-Ross, Kelen-Tüdos and extended Kelen-Tüdos graphical methods, along with the computer program COPOINT. Structural parameters of the copolymers were obtained by calculating the dyad sequence fractions of the monomers and their mean sequence lengths. Furthermore, a systematic and detailed investigation was performed on the thermal degradation of the copolymers compared with the respective homopolymers, by Thermogravimetric Analysis, TGA, and Differential Thermogravimetry, DTG, within the framework of the Ozawa-Flynn-Wall and Kissinger-Akahira-Sunose methodologies. It was concluded that the thermal stability of the copolymers was affected by the ratio of the two monomers in their structure and was increased with the addition of PEIC monomers. Additionally, the mathematical model of the mechanism through which the thermal decomposition of the homopolymer PPEIC takes place, was further investigated. Block copolymers PHIC-b-PPEIC were also synthesized via the same coordination polymerization approach and sequential addition of monomers starting from the polymerization of HIC. The samples were characterized by Size Exclusion Chromatography, SEC, and NMR spectroscopy. Their thermal decomposition profiles were studied by TGA and DTG measurements and were compared with the corresponding statistical copolymers. [ABSTRACT FROM AUTHOR]

In this work, we present a new borate, Ag 3 B 6 O 10 Br, as well as thermal properties of two recently reported members of M 3 B 6 O 10 X family, Ag 3 B 6 O 10 (NO 3) and Na 3 B 6 O 10 I. The structure of Ag 3 B 6 O 10 Br is non-centrosymmetric, Pnm 2 1 , and exhibits a new version of packing the ionic Ag–Br and covalent B–O frameworks. The non-centrosymmetry is induced by alternation of disordered and ordered borate "layers" normal to a. The Ag–Br sublattice is also strongly disordered and exhibits pronounced ahnarmonicity of thermal vibrations modeled using the Gram – Charlier series. Thermal behavior of Ag 3 B 6 O 10 Br, Ag 3 B 6 O 10 (NO 3) and Na 3 B 6 O 10 I was characterized using variable-temperature powder X-ray diffraction and thermal analysis. The thermal behavior of Ag 3 B 6 O 10 Br (α a = −0.5, α b = −7.4, α c = 41.5 at 200°С), Ag 3 B 6 O 10 (NO 3) (α a = 4.5, α b = 4.8, α c = 31.8 at 200°С), and Na 3 B 6 O 10 I (α a = 9.4, α b = −1.2, α c = 48.3 at 200°С) is strongly anisotropic due to the alignment of the hexaborate B 6 O 13 groups in the structure. [Display omitted] • A new non-centrosymmetric borate, Ag 3 B 6 O 10 Br was prepared. • Cationic [Ag 3 Br]3+sublattice shows strongly anharmonic displacement parameters. • Thermal expansion of Ag 3 B 6 O 10 X, X = Br, NO 3 , and Na 3 B 6 O 10 I is anisotropic. [ABSTRACT FROM AUTHOR]

• Dislocation loops are the main defect after irradiation of V-4Cr-4Ti. • Edge dislocations were found in the lattice images contributing to stress strengthening. • The irradiated samples exhibited different deformation behavior. • Aggregation of dislocation loops causes difficulty in activate slip system resulting in increased stresses. V-4Cr-4Ti was irradiated with V self-ions, and thermal properties, microstructure evolution and mechanical behaviour were analysed to elucidate the deformation mechanism of irradiation-induced defects. The results of the thermal analysis showed that no precipitates were produced during the irradiation process. Dislocation loops were the main defects after irradiation, and edge dislocations were found through lattice images with a lattice mismatch of 12.5%. The yield stress of irradiated samples increased, which may be due to interactions between dislocations during the deformation process. The deformation mechanism was discussed based on the Schmidt factor. [ABSTRACT FROM AUTHOR]

To address the critical issue of environmental sustainability, the application of nano-gelcoat has emerged as a promising approach to extend the service life and enhance the durability of glass fiber-reinforced polymer composites (GFRPs), thereby protecting the marine environment. Despite the extensive use of GFRPs in marine structures, their performance is significantly influenced by marine environmental factors. However, despite its potential, there is a lack of research on the experimental application of nano-gelcoat. To fully understand the underlying mechanisms and optimize the performance of nano-gelcoat application, more experimental investigations are required. In the present study, the hydrothermal aging of nano-gelcoat-coated glass fiber-reinforced polymer composites was investigated. Nano TiO 2 and nanoclay were used to enhance the performance of gelcoat. A three-month hydrothermal aging experiment was carried out in artificial seawater heated to 80 °C. Mechanical and water absorption properties of GFRPs and thermal, morphological and FTIR (Fourier transform infrared spectroscopy) properties of nano-gelcoat were investigated. An ANOVA analysis was performed to establish if the experimental results were statistically significant. The long-term aging tests showed that the addition of nano-TiO 2 improved water resistance and maintained the mechanical properties of the composite. It also improved the melting point. [Display omitted] • An experimental nano-gelcoat application was conducted on glass fiber reinforced epoxy composite. • The effect of hydrothermal aging on the mechanical, thermal and structural properties was investigated. • The long-term aging tests showed that nano-TiO 2 is a good candidate for nano-gelcoat application. • The ANOVA analysis performed on the experimental results indicated statistical significance. [ABSTRACT FROM AUTHOR]

[Display omitted] • New heteroleptic neutral molecular complexes with rare coordination environment Fe(III) atom. • Thermal decomposition lead to production of nanoparticles α-Fe 2 O 3. • Complete structural characterisation with interesting system of non-covalent interactions. Using solvothermal syntheses three heteroleptic neutral complex molecules [Fe(acac)(bpy)Cl 2 ] (1), [Fe(acac)Cl 2 (phen)] (2) and [Fe(acac)Cl 2 (4dmbpy)] (3) (bpy = 2,2́-bipyridine, phen = 1,10-phenanthroline, 4dmbpy = 4,4́-dimethyl-2,2́-bipyridine) were prepared from the acetylacetonate solution and characterized by chemical analyses and spectroscopic methods (IR and UV–Vis). All three complexes exhibit molecular structures with Fe(III) central atoms which are deformed octahedrally coordinated by one chelating N,Ń-donor ligand (bpy , phen or 4dmbpy), one chelating O,Ó-donor ligand acac and two olyhedr ligands. The crystal structures are stabilized by hydrogen bonds (complexes 1 – 3) and π-π interactions (complexes 1 and 2). The complexes exhibit rather high thermal stability up to about 200 °C. The first weight loss for 1 , 2 and 3 may correspond to decomposition of acac ligand. The residues of the thermal decompositions of the respective complexes 1 – 3 were formed by α-Fe 2 O 3 as shown by a combination of PXRD, SEM and EDX methods. [ABSTRACT FROM AUTHOR]

A new acesulfame derivative compound, trans -diaquabis(trans -4-aminoantipyrine)cobalt(II) acesulfamate that formulated as (C 30 H 38 CoN 8 O 12 S 2) was synthesized and characterized by X-ray diffraction method, FT-IR, UV–Vis techniques and Thermal analysis. The compound crystallizes in the orthorhombic space group Pbcn with parameters a = 28.0156 (10) Å, b = 9.4273 (4) Å, c = 13.7777 (5) Å, α = β = γ = 90°, Z = 4. Theoretical calculations have been carried out by using Density Functional Theory (DFT) method in the ground state. With a successful optimization, Mulliken population method, molecular electrostatic potential (MEP) and frontier molecular orbitals were calculated. In addition, the thermal behavior of the complex was investigated. Hirshfeld surface analyses (d norm surfaces and two-dimensional fingerprint plots) which reveal the nature of intermolecular interactions for the title compound were performed and discussed. The Hirshfeld surface analysis of the crystal structure specifies that the most important contributions for the crystal packing are from O⋯H/H⋯O (37.1%), H⋯H (33.5%) and C⋯H/H⋯C (16.5%) interactions. Image 1 • A new acesulfame derivative compound was characterized by FT-IR, UV and X-ray diffraction. • Chemical activity, MEP and MPA were investigated by DFT method. • The simultaneous TG-DTG and DTA curves of the complex were investigated. • The contributions for the crystal packing were determined with Hirshfeld surface. [ABSTRACT FROM AUTHOR]

A flame retardation property of polymer composites is being considered important to minimize the amount of heat release and the smoke production during the combustion. Therefore, this work aims to improve the flame retardation property of epoxy composites using ammonium polyphosphate (APP), one of the intumescent flame retardants (IFRs). However, APP could be migrated to the surface of composite due to the weak compatibility with epoxy resin. To prevent the migration, the surface modification method has taken place using various amines, acting as charring agent. In this study, we select the 4,4′-diaminodiphenylmethane (DDM) as both curing agent and charring agent for the surface modification on the APP, and their epoxy composites were prepared. Interestingly, we observe both the fast curing effect by analyzing the curing behavior of epoxy composite by Friedman method, and significant improvements of the thermal degradation, and flame retardancy of epoxy with adding the amine-modified APP (mAPP). Moreover, the epoxy/mAPP composites showed higher flame retardation properties and formed the compact char structures due to the attached DDM, which acted as an efficient charring agent to promote to form the carbonaceous char structures. Finally, we also found the correlation between the improvements of flame retardation properties, and char structures of epoxy composites by calculating the crosslink density (M c) using the theory of rubber elasticity. • Amine-modified ammonium polyphosphate was prepared via cationic ion exchange reaction with 4,4′-diaminodiphenylmethane. • The attached DDM can contribute to accelerate the curing and improve the flame retardation properties of epoxy composites.. • The relationship of flame retardation properties and char structure was found using theory of rubber elasticity. [ABSTRACT FROM AUTHOR]

Sensitivity analysis of Molecular Dynamics (MD) simulations has revealed that the predictions can be sensitive to the small perturbations in Interatomic Potential (IP) parameters. In order to make MD predictions for complex material systems more reliable, we performed uncertainty quantification of a high dimensional IP based on the Embedded Atom Method (EAM), a commonly utilized IP for metallic systems. The major contribution of this work is the prediction of a robust posterior probability distribution of the IP parameters by considering variations in the experimental values of various mechanical and thermal properties of FCC Al. The posterior probability distributions of the IP parameters were obtained using a Bayesian statistical framework. Reliability of potential parameters was assessed by performing MD simulations for a range of mechanical and thermal properties, using perturbed potential parameters. A comparison of the computed properties to existing experimental and first-principles data revealed that higher order properties such as grain boundary formation energy are sensitive (with variance of the order 10 5 ) to 1% perturbations. Using a Gaussian likelihood function, a posterior probability distribution of the IP parameters that minimizes the discrepancy between MD prediction and experimental values for various mechanical properties was obtained. Final properties of interest computed using this new distribution showed less sensitivity to changes in the IP parameters. Furthermore, the obtained posterior probability distribution reflects the uncertainty due to IP parameters and the quality of MD predictions is improved by propagating that uncertainty to the final properties. Thus, instead of obtaining point valued predictions from MD, probability distributions of the final properties are obtained using this framework. [ABSTRACT FROM AUTHOR]

• This study proposes ply-lam CLT with domestic plywood as the core material of CLT. • The thermal conductivities of ply-lam CLT in the radial was lowest at 0.104 W/m K. • The ply-lam CLT walls had lower thermal bridges than wood frame structure walls. • The ply-lam CLT walls with exterior insulation had lower thermal bridges. • The connection method using STS was able to maintain excellent insulation performance. Cross-laminated timber (CLT), developed in Europe for the utilization of low-grade wood, is an engineered wood product (EWP) with high carbon storage and low carbon emissions. CLT wooden houses have advantages such as reduction of greenhouse gases, shortening of construction period through precast and modular construction, improved of insulation performance and airtight performance, the realization of the high-rise wooden house. In this study, ply-laminate cross-laminated timber (ply-lam CLT) was prepared using domestic plywood as the core material of CLT, and the thermal properties and heat transfer performance of ply-lam CLT were analyzed. The thermal conductivities of the ply-lam CLT in the radial, tangential, and longitudinal directions were 0.104 W/(m K), 0.111 W/(m K), and 0.122 W/(m K), respectively. The results of the heat transfer analysis through ISO 10211 indicated that the ply-lam CLT walls had lower thermal bridges than wood frame structure walls. Moreover, the ply-lam CLT walls with exterior insulation had lower thermal bridges. In addition, the self-tapping screw (STS) joining method on all connections was able to maintain excellent insulation performance because of low thermal transmittance coefficient. In addition, it should be noted that the STS applied from inside overlapped with the geometric thermal bridges. [ABSTRACT FROM AUTHOR]

Abstract The thermal stability of organic-inorganic nano-composites prepared by a two-stage polymerization of urea-formaldehyde resin (UF) with furfuryl alcohol (FA) and TiO 2 before and after irradiation has been researched. The two resins of urea-formaldehyde–TiO 2 composites, named: UF/TiO 2 and UF/TiO 2 /FA, were synthesized. The thermal stability of obtained materials was studied by non-isothermal thermo-gravimetric analysis (TG), differential thermal gravimetry (DTG) and differential thermal analysis (DTA). UF hybrid composites have been irradiated (50 kGy) and after that their radiation stability was evaluated on the basis of thermal behavior. The free formaldehyde (HCOH) percentage in all prepared samples was determined. The minimum percentage values of free formaldehyde (0.04% and 0.03%) for UF/TiO 2 and UF/TiO 2 /FA, respectively, after irradiation dose of 50 kGy are detected. The shift of temperature values for selected mass losses (T 10 %) to a high temperature indicates the increase in thermal stability of samples based on UF resin modified with FA. [ABSTRACT FROM AUTHOR]

Abstract How to effectively enhance the flame retardancy of polyamide 46/polyphenylene oxide (PA46/PPO) alloy is one of the key issues needed to be addressed. In this work, organic-modified zirconium phosphate (OZrP) nanosheet was incorporated with PU-coated carbon fiber (CF) to flame-retard PA46/PPO alloy. The combination of OZrP and CF showed an outstanding combination effect in improving the flame retardancy and thermal stability of PA46/PPO. With the incorporation of 2 wt% OZrP and 20 wt% CF, the peak heat release rate and peak smoke production rate of PA46/PPO were reduced by 65.6% and 86.2%, respectively. Besides, the T i (temperature at 5% weight loss) and the residue of PA46/PPO/OZrP/CF were increased by 13.2 °C and 20.9 wt%, respectively, compared with PA46/PPO. The flame-retardant mechanism was further studied and revealed: when being burned, CF acted as the skeleton to improve the strength of char; simultaneously, OZrP catalyzed the carbonization of the polymer chains on the CF surface to form a strong and compact protective char layer, which blocked the transmission of heat and combustible gases, thus effectively improved the flame retardancy of the composite. Highlights • An efficient strategy simultaneously improving the flame retardancy and mechanical properties of PA46/PPO alloy was proposed. • The synergistic mechanism of OZrP nanosheet and PU-coated carbon fiber (CF) on the flame retardancy of PA46/PPO was revealed. • OZrP catalyzed the carbonization of the polymer chains on the CF surface to form a strong and compact protective char layer. [ABSTRACT FROM AUTHOR]

Abstract Controlling and adjusting the thermal properties of a compound to improve the additive manufacturing process of a polymer matrix through selective laser sintering is of key importance to achieve an optimized final part density as well as hardness. In the past, the purpose of adding mineral fillers to polymers was primarily one of cost reduction. Today, however, fillers are more often used to fulfil a functional role, such as improved thermal or mechanical properties of the polymer composite [ 1 ]. In this study, the influence of calcium carbonate as a mineral filler particle on the thermal properties in compression-molded polyamide 12 was investigated. The particle size distribution and the filler amount within the polyamide 12 matrix were varied. The melt viscosity at 190 °C, the melting speed, melting and crystallization point as well as crystallization time at 170 and 172 °C were analyzed. A relationship between these properties and the implementation of a specific amount of calcium carbonate with a certain particle size distribution was observed. The study concludes, that the thermal and flow properties of a polyamide 12 matrix can potentially be manipulated to improve a laser thermal sintering process insofar as the layer melt can be optimized as well as the crystallization process speeded up. [ABSTRACT FROM AUTHOR]

Novel borate Lu 2 Ba 3 B 6 O 15 was prepared using a multi-step high-temperature solid-state synthesis. It crystallizes in the cubic system, Ia 3 ¯ space group, a = 14.18197(3) Å, V = 2852.396(18) Å3, Z = 8, and it is isostructural with Y 2 Ba 3 B 6 O 15. The crystal structure is described as a framework composed of the edge-sharing large irregular BaO 9 polyhedra. The intersecting tunnels in this framework are filled with the lutetium atoms. Two planar BO 3 triangles are connected to each other by the vertices, forming the isolated B 2 O 5 pyroborate groups. The Lu 2 Ba 3 B 6 O 15 thermal behavior was investigated by thermal analysis and high-temperature X-ray powder diffraction (HTXRD). The Lu 2 Ba 3 B 6 O 15 sample starts to melt at 1058 °C. As the temperature increases, the coefficient of linear expansion increases (α a = 5.7 at 25 °C and 8.9 × 10−6 C−1 at 800 °C). The Rietveld refinement of the HTXRD data showed that thermal deformations of the non-rigid BaO 9 polyhedra have the greatest influence on the Lu 2 Ba 3 B 6 O 15 expansion among those of the other constituent polyhedra. • Lu 2 Ba 3 B 6 O 15 is prepared using a multi-step solid-state synthesis. • The Lu 2 Ba 3 B 6 O 15 crystal structure is refined by the Rietveld method. • The Lu 2 Ba 3 B 6 O 15 thermal behavior is investigated over a wide range of temperatures. • The BaO 9 thermal deformations contribute the most to the Lu 2 Ba 3 B 6 O 15 expansion. [ABSTRACT FROM AUTHOR]

Abstract The dimensional stability and dynamic mechanical properties on bamboo (non woven mat)/kenaf (woven mat) hybrid composites was carried out in this study. The hybridization effect of bamboo (B) and kenaf (K) fibers at different weight ratio were studied at B:K:70:30, and B:K:30:70 while maintaining total fiber loading of 40% by weight. The coefficient of thermal expansion (CTE) and dynamic mechanical properties of composites were analyzed by thermomechanical anlayzer (TMA), and dynamic mechanical analyzer (DMA), respectively. Positive hybridization effects were observed on B:K:50:50 hybrid composite with lowest CTE and highest dynamic mechanical properties among all composites. The dimensional stability were strongly influence by the fiber orientation where all composites shows prominent expansion in the transverse fibers direction but relatively low expansion in longitudinal fibers direction. Dynamic mechanical properties in term of complex modulus (E*), storage modulus (E′), loss modulus (E″), Tan delta and Cole-Cole plot were studied. DMA results reveal that B:K:50:50 hybrid composite possess the highest complex modulus due to the strong fiber/matrix interfacial bonding which supported by the coefficient of effectiveness and Cole-Cole plot. Hence, it is concluded that 50:50 weight ratio of bamboo and kenaf fibers is the optimum mixing ratio to enhance both dimensional and dynamic mechanical properties of hybrid composites, and it can be utilized for automotive or building materials applications which demand high dimensional stability and dynamic mechanical properties. Graphical abstract Image 1 [ABSTRACT FROM AUTHOR]

Abstract The hindered phenol antioxidant (HP) was grafted onto graphene oxide (GO) surface, and polyamide 6 (PA6)/GO-HP nano-composite was manufactured via melt processing. More efficient grafting of PA6 molecules onto GO surface was realized by forming hydrogen bonding, and GO was exfoliated and uniformly distributed in matrix. Compared with PA6/HP and PA6/GO, the oxidation induction time, thermal degradation temperature and E a of PA6/GO-HP composite increased significantly, retention of reduced viscosity and tensile strength were improved, revealing GO-HP hybrid was more efficient than HP or GO to resist thermal oxidation degradation of PA6. Such synergistic thermal oxidative stabilization mechanism was further revealed. Highlights • GO-HP hybrid was prepared by grafting hindered phenol antioxidant onto GO surface. • PA6/GO-HP nano-composite was manufactured via melt processing. • Exfoliated GO with high graft of PA6 uniformly dispersed in PA6 in presence of HP. • Synergistic thermal oxidative stabilization effect of GO-HP on PA6 was achieved. [ABSTRACT FROM AUTHOR]

Abstract Amorphous calcium phosphate (ACP) is essential in formation of mineralized bone and using as a bone substitute. This study presents new aspects of carbonated ACP crystallization during heat treatment. Initially synthesis end pH and drying method (80 °C or freeze-drying) of ACP were varied. Thermal behaviour and structure of differently obtained ACP were evaluated using DSC-TGA, heating microscopy, XRD, FT-IR. In addition, degree of crystallinity (DOC), phase composition and chemical group information were compared for as-synthesized and heat-treated (crystallization end T and 1200 °C) ACP. For the first time DSC-TGA and heating microscopy methods were correlated. DOC of samples dried at 80 °C was synthesis end pH dependent. Heat treatment without temperature hold at crystallization end T produced materials with DOC of 82–91%, thus proving efficiency of low temperature processing. Variations in drying method and synthesis end pH affect structure of the samples heat treated at crystallization end T, but not at 1200 °C. [ABSTRACT FROM AUTHOR]

Abstract The effect of Y 2 O 3 on the glass transition kinetics, crystallization kinetics, phase separation and crystallization behavior of 60ZnO–30B 2 O 3 –10SiO 2 glass has been investigated by non-isothermal differential thermal analysis, scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The glass transition activation energies E g calculated by using both Kissinger and Moynihan model decrease from 668 kJ/mol to 573 kJ/mol for Kissinger model, and 682 kJ/mol to 587 kJ/mol for Moynihan model with the increase of yttrium oxide doping content from 0 to 6 mol%. And the glass crystallization kinetics parameters, crystallization activation energy E c and Avrami exponent n stands for crystal growth, are also obtained on the basis of several well developed equations. Increase of about 58 kJ/mol in Ec values obtained by different theoretical equations is caused by addition of 6 mol% yttrium oxide into 60ZnO–30B 2 O 3 –10SiO 2 glass, and the Avrami exponent (n close to 2) suggests that crystal growth in 60ZnO–30B 2 O 3 –10SiO 2 glass doped with or without yttrium is mainly one-dimensional growth of crystals. The results on the phase separation and crystallization behavior occurred at 893 K and 993 K respectively for base and doped glass, are well consistent with the glass transition and crystallization kinetics results. Hence, addition of yttrium oxide into 60ZnO–30B 2 O 3 –10SiO 2 glass decrease the glass transition activation energy while increase the crystallization activation energy of glass, thereby the stability of glass structure is improved. Phase separation phenomenon and crystallization behavior occurred at glass surface provide some useful information for preparing glass ceramics with micro- or nano-crystals in surface. [ABSTRACT FROM AUTHOR]