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• Tannic acid is neither a good flame retardant nor a highly swelling material. • TA combined with CLS reduces flammability of biocomposite by 30 % compared to PLA. • Mixing of TA with CLS in melt doesn't allow for PHRR reduction of more than 20 %. The purpose of this study was to determine the quantitative and qualitative effects of the form of natural phenolic compounds (NPCs) on the decomposition of polylactide (PLA) under different measurement conditions. For this purpose, thermogravimetry analysis (TGA), differential scanning calorimetry (DSC), and pyrolysis-combustion flow calorimetry (PCFC) analyses were carried out not only on individual raw materials like calcium lignosulfonate (BX), tannic acid (TA), BX chemically modified with TA (BMT), but also on PLA/BX, PLA/TA, and PLA/BMT composites with 3, 6, and 9 wt.% of filler. Moreover, the work checked whether to obtain satisfactory results it is necessary to carry out chemical modification lasting many hours, or whether simple physical mixing of ingredients (TABX) is enough, e.g. in proportions 1:2, 2:4, 3:6. The results of these analyses showed that TA is neither a good flame retardant nor a highly swelling material, but when combined with BX physically or chemically, it can produce an interesting synergistic effect. This work proves that chemically obtained BMT hybrid material allows to reduce flammability by 30 % compared to PLA which cannot be achieved by physically mixing these components in a polymer melt. On the other hand, the addition of TABX is sufficient to achieve a good thermal stabilization effect under processing conditions. [Display omitted] [ABSTRACT FROM AUTHOR]

• Aromatic bismaleimides and aliphatic bismaleimides were prepared. • Aliphatic bismaleimides have lower activation energy. • Aromatic bismaleimides possess superior thermal stability and lower dielectric loss. • Aliphatic bismaleimides exhibit lower dielectric constant and low water absorption. In this paper, three aromatic bismaleimides (BMI-70, BMI-DE and BMI-80) and two aliphatic bismaleimides (BMI-DDA and BMI-C36) were synthesized. The structures were characterized using nuclear magnetic resonance (NMR) spectra and Fourier transform infrared (FT-IR) spectra. Their polymerization behaviors were discussed by non-isothermal differential scanning calorimetry (DSC). The thermal and dielectric properties of the poly(bismaleimide) were investigated using thermogravimetric analysis (TGA), dynamic thermo-mechanical analysis (DMA), and an impedance analyzer. The results indicate that the aliphatic bismaleimides exhibit lower apparent activation energies and dielectric properties, with BMI-DDA displaying an average activation energy of 105.5 kJ mol−1 and the dielectric constant of P(BMI-C36) is 2.558 @ 10 MHz. The aromatic polybismaleimides possessed better thermal stability, among which, the 5 % thermal decomposition temperature (T d,5) of P(BMI-70) was 513.5 °C, and the residual carbon rate at 800 °C was 44.6 %. In additional, water absorption was studied and their saturated water absorption was less than 4 %. [Display omitted] [ABSTRACT FROM AUTHOR]

• Electron-donating substituent increased the polymerization activity of benzoxazine. • Electron-withdrawing substituent increased the heat resistance of polybenzoxazine. • Impacts of meta-substituents on thermal stability of polybenzoxazines were complex. The molecular structure of benzoxazine is closely related to its polymerization activity and the properties of its polymer. In this work, benzoxazines were successfully synthesized from phenol, paraformaldehyde and meta-substituted anilines. Their polymerization behaviors were discussed by non-isothermal differential scanning calorimetry (DSC). Moreover, the thermal properties of corresponding polybenzoxazines were evaluated using DSC and thermogravimetric analysis. The results showed that the electron-withdrawing substituent increased the polymerization temperature while the electron-donating substituent lowered the polymerization temperature. The glass transition temperature decreased for polybenzoxazine with electron-donating substituent but elevated for polybenzoxazine with electron-withdrawing substituent. Besides, the thermal stability and thermal degradation mechanism of polybenzoxazine were significantly affected by the substituent. This work supplied further insight in the structure-property relationship of benzoxazine resin. [Display omitted] [ABSTRACT FROM AUTHOR]

• Poly(ethylene furanoate) (PEF) nanocomposites have been successfully synthesized. • Thermal stability and decomposition kinetics of PEF were investigated. • Thermogravimetric analysis proved that nanocomposites exhibited good thermal stability. • Degradation occurred via heterolytic β-hydrogen scission and α-homolytic scission. Poly(ethylene 2,5-furan dicarboxylate) (PEF) based nanocomposites containing different nanoparticles like Ag, TiO 2 , ZnO, ZrO 2 Ce-Bioglass, have been synthesized via in-situ polymerization techniques targeting food packaging applications. Zeta potential measurements showed an increase in the negative zeta potential value due to an increase in the surface charge density of the nanocomposites. Thermogravimetric analysis results proved that, except PEF-ZnO nanocomposite, all the other nanocomposites exhibited good resistance to thermal degradation without serious mass loss until 330 °C. Thermal decomposition kinetic analysis and the dependence of activation energy on the degree of conversion (α), indicated that the presence of ZnO nanoparticles influences, the degradation mechanism of PEF. In contrast, the presence of Ce-Bioglass nanoparticles leads to a slower degradation process, contributing to the enhanced resistance to thermal degradation of the PEF-Bioglass nanocomposite. The thermal degradation mechanism of PEF nanocomposites analyzed by pyrolysis‒gas chromatography/mass spectrometry (Py-GC/MS) indicated that the primary thermal degradation mechanism for the studied nanocomposites was β-hydrogen bond scission, while to a lesser extent, α-hydrogen bond scission products were noted in PEF-TiO 2 and PEF-ZrO 2 nanocomposites. [ABSTRACT FROM AUTHOR]

• The mixture of boric acid and borax slow down PLA's fire speed by roughly 66 %. • Thermal degradation temperature lowered by the addition of boron compounds to PLA. • Flexural and Young's modulus prominently rise by roughly 20 % and 22 %, respectively. • 5 wt% boron compounds reinforced composites have better mechanical–thermal results. This study aims to understand how ulexite, boric acid-borax mixtures (1:1), and zinc borate fillers affect the thermal and mechanical properties of the poly (lactic acid) (PLA). For this purpose, three different boron fillers were added to the PLA matrix at four different concentrations of 3 %, 5 %, 8 %, and 12% wt. UL-94 test was conducted to comprehend the impacts of boron fillers on the fire resistance of the biocomposites. Thermogravimetric analysis was applied to determine the thermal stability, mass loss, and decomposition temperature of the samples. The biocomposite's significant mechanical properties, such as tensile strength, flexural strength, Young's modulus, and elongation at break, were assessed using tensile and three-point bending tests. Although the tensile and flexural strengths of PLA reduced, flexural and Young's modulus rose by roughly 20 % and 22 %, respectively, with rising boron filler rates. [ABSTRACT FROM AUTHOR]

• Rigid polyurethane foam as the preferred thermal insulation. • Analysis of the influence of fly ash on material thermal conductivity. • Calculation of the heat balance for a wall with polyurethane insulation. • Study of the temperature field in the cross-section of the wall. Limitations in natural resource availability have a significant impact on prices of thermal energy. As a result, a growth of interest in the technology of insulation materials is observed. The paper presents a comparative analysis of rigid polyurethane foams, which are widely used as insulation materials. Rigid polyurethane foam with 10 wt.% addition of coal fly ash is compared to a reference foam, without any addition. The thermal conductivity coefficient of polyurethane materials was determined by the Hot Disk device. Heat transfer for both types of foams was modelled. As a result of the numerical modelling, the temperature field for the wall was obtained. The results of the computations have shown differences in energy losses. Conducted analyses demonstrate that the modified polyurethane foam (with the addition of coal fly ash) performs better as an insulation material. The reduction of heat requirement is 2.9 %. An environmental analysis of the insulation materials was also carried out. Using the SUBRAW index method it was calculated that embodied energy and the carbon footprint are lower in the case of the modified polyurethane compared to the unmodified foam. [ABSTRACT FROM AUTHOR]

• Three polyzwitterions (PZIs) were synthesized based on the sulfobetaine moiety. • LiCl salt, added in molar ratios, affects the PZI structure and thermal properties. • Salt ions disrupt dipolar crosslinks of PZI side groups increasing chain mobility. • Ratchet drying method in DSC/TMDSC removes surface and molecularly bound water. • With added salt the PZI heat capacity increment of unconfined liquid is reached. Thermal and structural properties of polyzwitterions (PZI)s comprising the sulfobetaine moiety were studied as a function of LiCl addition and variations in monomer chemistry. The polyzwitterions chosen for this study are: poly(sulfobetaine methacrylate), PSBMA; poly(sulfobetaine acrylate), PSBA; and, poly(ethyl sulfobetaine methacrylate), PESBMA. When LiCl salt is added, the Li+and Cl− ions disrupt the dipole-dipole electrostatic interaction of the PZI side groups. Fourier transform infrared spectroscopy shows that the vibrational frequencies of the symmetric and asymmetric S = O bonds increase as LiCl content increases. Structural studies by wide angle X-ray scattering show that all the PZIs are amorphous, and the average interatomic spacing, d, increases in the order: d PSBA (= 0.456±0.006nm) < d PSBMA (= 0.474±0.015nm) < d PESBMA (= 0.493±0.011nm). Upon the addition of LiCl, d -spacing for a given PZI decreases as LiCl content increases. Thermogravimetry showed that PZIs had degradation onset temperatures T d ∼ 300°C. As LiCl content increases, the onset temperature of degradation decreases suggesting that the disruption of dipole-dipole crosslinks destabilizes the polymer. All the PZIs are hydrophilic and hygroscopic, and a drying procedure was developed so that well-defined glass-to-liquid transitions could be observed in the dry solid state. PZIs without LiCl have glass transition temperatures, T g , increasing in the order: T g , PSBA (= 200±1°C) < T g , PESBMA (= 204±1°C) < T g , PSBMA (= 237±1°C). As the LiCl content increases, T g decreases, and the liquid state heat capacity increases, in all PZIs. The specific heat capacity increment at T g was studied for PSBA as a function of LiCl content. In PSBA, the heat capacity increment reached a maximum for molar ZI:LiCl content at and above 1:1, and its value agreed well with predictions based on an empirical bead model of polymers. Thermal data on the dry state of PZI-LiCl complexes suggest an analogy between electrostatically crosslinked, fully amorphous PZIs and semicrystalline polymers. The dipolar crosslinks confine the molecular motion of PZIs just as crystal domains confine the molecular motion of the amorphous phase in semicrystalline polymers. [Display omitted] [ABSTRACT FROM AUTHOR]

• The fabricated α-Al 2 O 3 is an ideal skeleton to load PCMs. • A silica layer is coated to prevent the leakage of PCMs. • The composite PCM has excellent thermal properties and physicochemical stability. • The PCM modified cement has sufficient strength and excellent thermal properties. The building energy consumption is increasing constantly with the rapid development of global economy. Integrating PCMs into cementitious materials has great potential in improving building energy efficiency through thermal regulation. In this study, a novel α-Al 2 O 3 spherical skeleton is fabricated to create a new kind of form stable phase-change material (FSPCM). Then its surface is coated with a silica layer to prevent the leakage of the inner phase-change materials and intensify the binding with cement. Scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and leakage test demonstrate its spherical structure, high thermal storage capacity and stability, and excellent leakproof performance. Further, the novel FSPCM is added into Portland cement at the weight ratio of 20% to prepare the thermal storage cement-based materials (TSCM). The properties of TSCM are evaluated by compressive test, calorimetry, SEM and infrared thermography. The results show that TSCM presents satisfying mechanical property (47.1 MPa at 28 d), less hydration heat, good workability (200 mm for the fluidity) and superior thermos-regulating ability (maximum ΔT = 10.5 K). From this work, it can be inferred that the designed TSCM with 20 wt% of FSPCM is a promising candidate for building energy conservation. [ABSTRACT FROM AUTHOR]

• The combined hybrid fillers are obtained by spray-drying method. • The polymer composites with combined fillers possess better thermal conduction property than that with untreated fillers. • Interface thermal resistance is decreased in the composites with combined fillers. This paper reports a new way of improving the thermal conduction property of polymer composites composed of silicone rubber and combined fillers obtained by attaching spherical alumina particles to carbon fibers using spray-drying method. The experimental results showed that the thermal conductivities of the polymer composites were 16, 28, 30, 32, and 42% higher than those of composites with untreated carbon fibers at the same content. The analysis based on effective medium theory revealed that the interface thermal resistance decreases from 1.2 × 10−6 m2 K/W to 8.5 × 10−7 m2 K/W in polymer composites. It demonstrates that the combined fillers could decrease the interface thermal resistance to improve the thermal conduction property of polymer composites, and thus are promising for the development of high-performance thermally conductive products. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Carbonization corn cobs were a perfect carrier matrix to form shape stabilized PCMs. • Carbonization corn cobs exhibit a highly porous structure comprising rough micropores. • Latent heat, stability, and thermal properties of PCMs were excellent. • The thermal conductivity of LA-SA/CNCC was 87.5% greater than that of LA-SA. Abstract In this study, novel form-stable composite phase change materials (FS-CPCMs) were prepared by the incorporation of a eutectic mixture of lauric-stearic acid (LA-SA) into carbonization corn cob (CNCC). CNCC served as a good supporting material that not only prevented the leakage of LA-SA but also enhanced its thermal conductivity. Scanning electron microscopy results demonstrated that CNCC exhibits a highly porous structure comprising rough micropores. The retention of 77.9 wt% of LA-SA in CNCC without leakage was observed. Differential scanning calorimetry results revealed that LA-SA/CNCC FS-CPCMs melt at 35.1 °C with a latent heat of 148.3 J/g and solidify at 29.7 °C with a latent heat of 144.2 J/g. The thermal conductivity of LA-SA/CNCC FS-CPCMs was approximately 87.5% greater than that of LA-SA. Thermogravimetric analysis and 200-cycle experiments indicated that the LA-SA/CNCC FS-CPCMs exhibit excellent thermal stability and form-stable performance. Therefore, the as-prepared LA-SA/CNCC FS-CPCMs demonstrate promise for building energy-efficiency applications. [ABSTRACT FROM AUTHOR]

Highlights • Epoxy-based dual-curing system with outstanding sequential character is described. • Kinetics are analyzed using isoconversional and model fitting methods. • Global and individual curing stages are properly simulated using either method. Abstract The curing kinetics of a sequential dual-curing system based on an off-stoichiometric amine-epoxy formulation with intermediate latent reactivity has been analyzed. The first curing stage is an epoxy-amine polycondensation taking place at low temperatures, while the second curing stage is an anionic homopolymerization of the excess epoxy groups, taking place at high temperatures and catalyzed by a latent base. The different reactivity of both polymerization processes allows an excellent separation into well-defined curing stages each of which can be analyzed individually. The kinetics of the two curing stages have been analyzed by integral isoconversional procedures and model-fitting methods. Both methodologies successfully simulated each curing stage and also the global curing process, showing that it is possible to control the activation of both curing stages. Isoconversional integral analysis is a simple yet powerful method that can be used for the simulation of temperature-controlled curing programmes. Model-fitting analysis is more suitable for the flexible simulation of processing scenarios such as the curing of composites. [ABSTRACT FROM AUTHOR]

Highlights • Thermal properties of apple pomace flours were followed by DSC and TG/DTG. • Glass transition (T g) above storage temperature ensure a prolonged shelf life of apple pomace flour. • Determination of kinetic parameters of apple pomace flour thermal degradation. • Organic samples of apple pomace flour were found to have a higher thermal stability. Abstract Using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA) thermal characteristics and degradation kinetic parameters of apple pomace flours (APF1–5), obtained by dehydration of apple pomace (originating from single and mixed apple varieties, grown both organically and conventionally) and ground to particle size below of 300 μm, were determined. Glass transition (T g) close to common storage temperature (21 °C) was ascribed to commercial sample and T g well above it (28–38 °C) to APF1–5. Both values of T g and low water activity (0.2-0.4) prolong APF shelf-life. The kinetic parameters of the thermal degradation process: activation energy (E) in the range from 83 to118 kJ/mol, logarithmic value of pre-exponential factor (ln(A/min−1)) in the range from 20 to 28, and rate constant (k 200) from 0.143 to 0.278 min−1 were calculated. APF samples were grouped according to rate constant (k 200) values of thermal degradation process at baking temperature (200 °C). Organic samples were found to have a higher thermal stability. [ABSTRACT FROM AUTHOR]

Highlights • High temperature X-Ray Diffraction analysis of Ag-Li alloys. • Dilatometric measurements of Ag-rich alloys from Ag-Li system. • Electric conductivity and reversibility of Ag-rich alloys from Ag-Li system. • The structural and physical properties of Ag-rich alloys from Ag-Li system. Abstract The structural and physical properties of the Ag-rich alloys from Ag-Li system (Ag 90 Li 10 , Ag 80 Li 20 , Ag 70 Li 30 , Ag 60 Li 40 , Ag 57 Li 43 , Ag 55 Li 45 , Ag 52 Li 48 , and Ag 50 Li 50) were performed with the use of the three different methods. All tested alloys were prepared from high purity metals (Ag and Li) by melting in a glove-box filled with high purity argon, with a very low concentration of impurities. The high-temperature X-ray diffraction investigations were conducted to confirm the structure of the prepared alloys. The thermal expansion measurements of the Ag-rich alloys were carried out by an optical, horizontal dilatometer at the temperature range from 298 to 665 K. Moreover, the electrical conductivity of investigated Ag-rich alloys was measured at room temperature. The results of X-ray diffraction phase analysis, thermal expansion and electrical conductivity measurements, obtained in these studies, may undermine the reliability of the present phase diagram of Ag-Li, which makes it necessary to verify the existing phase equilibria. Further thermodynamic and physicochemical studies of Ag-Li system are crucial to get complete data for the optimization of the thermodynamic properties and calculation of the reliable phase diagram of the Ag-Li system. [ABSTRACT FROM AUTHOR]

Highlights • K of the A707 alloy decreases from 154 to 124 W/m K with increasing temperature. • The α TCC value for the studied alloy was determined to be -4.17 × 10−4 K. • The σ of A707 alloy exponentially decreases with increasing temperature. • Thermal diffusivity decreased from 61.6 × 10−6 to 50.2 × 10−6 m2/s with increasing T. Abstract In the present work, the thermal conductivity, electrical conductivity, enthalpy of fusion, specific heat capacity and thermal diffusivity of the A707 alloy (Al–4.5 Zn–1.2 Mg–0.15 Cr–0.15 Zr wt.%) have been investigated. Phase identification of the studied alloy was investigated with energy dispersive X-ray analysis and X-ray diffraction techniques. Thermal conductivity of as-cast A707 alloy was measured using Comparison Cut Bar Method in the temperature range of 300–800 K. With the increase of temperature, thermal conductivity decreased gradually in as-cast A707 alloy. The electrical conductivities of the sample were obtained with the Wiedemann–Franz equation by using the measured thermal conductivity values. Thermal conductivity coefficients for the alloy were obtained from the graphs of thermal conductivity versus temperature. The enthalpy of fusion and the specific heat capacity during the transformation were also determined. Thermal diffusivity changes were calculated as a function of temperature through the obtained thermal data. [ABSTRACT FROM AUTHOR]

Highlights • Growth of (1-x)PMN-xPT perovskite single crystals in the composition range of x = 0.25, 0.35, and 0.40. • The photopyroelectric calorimetry (PPE) configuration in the back and front was used. • Systematic comparison between (1-x)PMN-xPT single crystals and ceramics. • The influence of increasing PT(x) amount on pyroelectric and thermal properties. Abstract Thermal energy harvesting has great potential for environment-friendly self-powered devices. Materials based on relaxor-ferroelectric single crystals such as PMN-PT (lead titanium-lead magnesium niobate) have gained significant interest for their outstanding properties. In this context, single crystals from (1-x)PbMg 1/3 Nb 2/3 O 3 -xPbTiO 3 solid solution were grown using the modified Bridgman method in the composition range of x = 0.25, 0.35, and 0.40. This paper presents a systematic comparison between (1-x)PMN-xPT single crystals and ceramics involving the effect of composition and the crystal orientation on thermal properties assuming a one-dimensional heat-flow process. Results demonstrate that thermal and pyroelectrical properties are intimately coupled to the chemical composition, where the studied single crystals have a good performances compared to their corresponding ceramics, which make them very promising for efficient cooling systems, and IR devices applications. [ABSTRACT FROM AUTHOR]

Highlights • Thermal conductivity of nanofluids is enhanced by mixing two different nanoparticles. • Critical heat flux for hybrid nanofluids in pool boiling is investigated. • Effect of nanoparticle deposition on heat transfer coefficient is explored. Abstract Boiling is a process with maximum heat transfer coefficient (HTC) and heat transfer rate. Researchers are working with techniques such as surface modifications and nanoparticle suspensions in base fluids to enhance the thermal performance. The present work focuses on the enhancement of thermal properties and critical heat flux (CHF) by mixing two different nanoparticles viz., alumina and copper oxide at various concentrations in Deionized (DI) water. Volume concentrations of 0.01 - 0.1% are prepared and the stability of nanofluids is confirmed by Zeta potential. Thermal conductivity of hybrid nanofluids is enhanced by 15.72% for 0.1% concentration at room temperature compared with DI water. CHF of hybrid nanofluids is always higher than single type nanofluid. Maximum enhancement of 49.84% in CHF is obtained for 0.1% concentration. HTC is enhanced by 7.1 and 6.72% for 0.01 and 0.03% volume concentrations than DI water and starts decreasing with increasing volume concentrations. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Dark, milk and white chocolates and fats extracted from them were researched. • The thermal and textural properties of chocolates were investigated. • The shape of DSC melting curves of chocolates depends on numerous factors. • TG and DTG are useful tools to determine differences between amount of dark, milk and white chocolates ingredients. Abstract The effect of different composition of dark, milk and white chocolate samples on their thermal and textural characteristics was investigated. Thermal behaviour was evaluated by means of differential scanning calorimetry (DSC) and thermogravimetry (TG). The research included melting characteristic of chocolates and fats extracted from chocolates. Additionally, TG and DTG curves of tested samples have been analysed. Mechanical texture parameters (hardness and work) have been determined on the basis of a penetration test by strength machine (ZWICK). The melting characteristics determined for cocoa butter and milk fat before the addition to chocolate and after extraction from chocolate was very similar. The course of DSC melting curves of chocolates depend on numerous factors such as the presence and quality of fat, addition of sugar and/or emulsifiers and particle size distribution of chocolate. White chocolate was characterized by mechanical parameters significantly lower than milk and dark chocolate. [ABSTRACT FROM AUTHOR]

Highlights • Binary and ternary lanthanide complexes with N -phenylanthranilic acid and 1,10-phenanthroline were synthesized. • Formation of the complexes was confirmed by FTIR and XRD methods. • Previously unreported thermal behaviour of these compounds was investigated in oxidative and inert atmospheres. • The coupled TG-FITR-MS technique provided information about gaseous products of thermal decomposition. • The antibacterial activity of the obtained compounds were proved. Abstract New binuclear binary and ternary complexes of Sm(III), Eu(III), and Gd(III) ions with N -phenylanthranilic acid and 1,10-phenanthroline were obtained in solid phase and characterized by chemical and elemental analysis, molar conductance, UV–vis and IR spectroscopies as well as thermoanalytical techniques (TG/DTG–DSC coupled with MS and FT-IR). The dilution method was used to examine the antibacterial activity of the synthesized compounds. The spectroscopic studies indicated that the carboxylate group of N -phenylantranilate ligand is involved in the coordination of metal ion both in binary and ternary complexes. Thermal decomposition of the obtained compounds was carried out in air and nitrogen atmosphere. During heating the complexes decompose via intermediate products to the oxide (Ln 2 O 3) in air atmosphere and to the oxide (Ln 2 O 3) or oxide polluted by carbon (Ln 2 O 3 +nC) in nitrogen atmosphere. The dehydration process was discussed in relation to the nature of water present in these compounds. Using coupled TG-FTIR-MS techniques the decomposition pathways of the synthesized compounds were examined. Additionally, gaseous products released during pyrolysis and thermal oxidation of the complexes were identified. All the complexes exhibit marked activity against two Gram-negative (Escherichia coli and Pseudomonas aeruginosa) and one Gram-positive (Staphylococcus aureus) bacterial strains. The ternary complexes, especially Gd(III) complex in comparison with the binary ones, have enhanced activity against Escherichia coli. Moreover, antibacterial activity of the synthesized compounds with respect to Pseudomonas aeruginosa is comparable to tetracycline and greater than for kanamycin, erythromycin, and ampicillin. [ABSTRACT FROM AUTHOR]

Highlights • X-ray diffraction analysis revealed the formation of Sn x Sb 2 S y (1 ≤ x ≤ 3, 4 ≤ y ≤ 6) sulfosalts thin films. • The films have strong diffraction peaks at 2θ = 31.65°, 31.67° and 31.58° for SnSb 2 S 4 , Sn 2 Sb 2 S 5 , and Sn 3 Sb 2 S 6 , respectively. • Thermal conductivity values are from 30.4 Wm−1 K−1 to 79.2 Wm−1 K−1. • The thermal diffusivity values are from 4.20 10−6 m2s-1 to 20.5 10−6 m2s-1. • The SnSb 2 S 4 thin film annealed at 200 °C is a good candidate for solar cell application. Abstract SnSb 2 S 4 , Sn 2 Sb 2 S 5 and Sn 3 Sb 2 S 6 thin films were obtained by a vacuum thermal evaporation method. The films were thermally annealed at 200 °C in tube furnace. Their structural and thermal properties are studied by X-ray diffraction and electro-pyroelectric technique. The X-ray diffraction analysis revealed that the polycrystalline Sn x Sb 2 S y films were successfully obtained using an annealing temperature of 200 °C. The thermal measurements show that these thin films have thermal conductivity ranging from 30.4 to 79.2 Wm−1 K−1 and the highest value belongs to film of SnSb 2 S 4 material annealed at 200 °C. Also, It is found that Sn x Sb 2 S y films exhibit thermal diffusivity values situated in (4.20–20.5)10-6 m2s-1 domain. The most significant result of the present study is that SnSb 2 S 4 thin film annealed at 200 °C seems a good candidate for solar cell application. [ABSTRACT FROM AUTHOR]

Highlights • Zinc induces a decrease of melting temperature. • Addition of zinc in the glass matrix induces a decrease in excess entropy. • Strontium induces an increase of crystallisation temperature. • Addition of strontium in the glass matrix induces an increase in excess entropy. Abstract This research is based on the study of thermal behaviour of bioactive glass in the quaternary system SiO 2 -CaO-Na 2 O-P 2 O 5 doped with metallic elements such as Zn and Sr destined for use as bone biomaterial. It encompasses glass transition temperature, crystallization temperature and melting temperature. This work is based on both determination and comparison of the effects of Zn and Sr on thermal characteristics after their introduction in the glass matrix. Thermal stability and excess entropy of all studied glasses have been calculated. Obtained results highlight the different effects of doping on the glasses thermal behaviour. Most notable effects are the sharp decrease of melting temperature of 10 wt% Zn-doped glass and the increase of crystallization temperature of 10 wt% Sr-doped glass. Furthermore, excess entropy of pure glass increases with addition of Sr and decreases with addition of Zn. [ABSTRACT FROM AUTHOR]

Highlights • Vaporization and thermodynamic properties in the La 2 O 3 -HfO 2 system were studied. • At 2337 K the main vapor species over the La 2 O 3 -HfO 2 system were LaO and O. • Vaporization of HfO 2 started at temperatures higher than 2600 K. • Thermodynamic properties showed negative deviations from ideality in this system. Abstract The La 2 O 3 -HfO 2 system is a base for many advanced materials used in high temperature technologies and nuclear industry. Information on vaporization processes and thermodynamic properties of ceramics based on the La 2 O 3 -HfO 2 system is important to prevent the La 2 O 3 selective vaporization during their synthesis or usage. The study was carried out by the Knudsen effusion mass spectrometric method. At 2337 K LaO and O were the main vapor species over the samples in the La 2 O 3 -HfO 2 system. The dependence of the La 2 O 3 activities on composition in the La 2 O 3 -HfO 2 system was obtained by the differential mass spectrometric method. The HfO 2 activities, excess Gibbs energies and Gibbs energies of mixing were evaluated in the solid solutions of the La 2 O 3 -HfO 2 system at 2337 K using the Gibbs-Duhem equation and showed significant negative deviations from ideality. The solid solution presumably with the pyrochlore structure was characterized with the strongest negative deviations. [ABSTRACT FROM AUTHOR]

Highlights • Aromatic diamine-based benzoxazines with various blocking positions are synthesized. • Different blocking positions vary the curing temperature of the benzoxazine monomers. • Hydrogen bonding inhibits autocatalysis in network with arylamine Mannich bridge. • Changes in blocking positions causes dramatic differences in T g after polymerization. • Thermal stability reduces similarly regardless of specific blocking position. Abstract To elucidate the contribution of blocking positions on aromatic diamine-based benzoxazines, we prepared several 4,4′-bis(3,4-dihydro-2 H -1,3-benzoxazin-3-yl) diphenyl methane monomers with different phenols. The molecular chemical structures of the bi-functional monomers are characterized by FTIR and 1H-NMR. Particularly, the newly developed m -cresol based benzoxazine is further confirmed by 13C-NMR and ESI-MS and the oxazine ring position is verified. The curing behaviors are investigated by dynamic differential scanning calorimetry (DSC). Activation energies are analyzed by Kissinger, Ozawa and Starink methods at various heating rates. Due to structure difference in polymerized network, polymer with high amount of arylamine Mannich bridge shows low autocatalysis capability. The glass transition temperature (T g) is closely related to the blocking position while thermal stability decreases comparatively regardless of the blocking position. High arylamine Mannich bridging leads to large amount of dangling groups, which reduces the decomposition peak temperature. [ABSTRACT FROM AUTHOR]

Highlights • z-TACOT is a highly thermostable explosive. • Kinetic parameters were determined for initial stage of z-TACOT decomposition. • Calculated maximum safe temperature for processing z-TACOT is 263 °C. Abstract 1,3,7,9-tetranitrodibenzo-1,3a,4,6a-tetraazapentalen (z-TACOT) is a thermostable compound which exhibits low-sensitivity to external stimuli. At elevated temperature it undergoes thermal decomposition. Thermal properties and safety of z-TACOT use in terms of the heat-explosion hazard were examined. The obtained kinetic parameters of the decomposition reaction and thermal capacity of z-TACOT were used to determine the maximum safe temperature of technological processes which involve z-TACOT. The temperature is 266 °C. Based on the attained safety parameters z-TACOT can be classified as a non-reactive, stable compound which does not exhibit dangerous behaviour in the Koenen test. [ABSTRACT FROM AUTHOR]

• Thermal cycling in dilatometry experiments and simulation • Peak occurance in Coefficient of Thermal Expansion curve during first heating • Temperature dependent simulation of interface and residual stress • Microstructural damage initiation and propagation in Interpenetrating Composites • in-situ Scanning Electron Microscopy setup with Digital Image Correlation [Display omitted] An interpenetrating metal-ceramic composite (IMCC), consisting of an open-porous alumina preform (26 vol %), infiltrated with an AlSi10Mg alloy is investigated for its thermal properties and the microstructural impact on the thermal cycling behavior. Specific heat capacity, thermal conductivity and the coefficient of thermal expansion are investigated experimentally. Next to dilatometry experiments, an in-situ SEM setup with digital image correlation of the natural microstructure of the composite is used as a recognizable pattern on the sample surface to evaluate strain and microstructural changes during heating and cooling. The interpenetrating phase composite is also modelled based on reconstructed and generated microstructures. Extensive numerical studies are conducted with varying boundary conditions, interface properties, initial cooling temperatures, temperature dependent material properties and inclusion of pores. Microstructural investigations show phenomena of plasticity, creep, crack formation and interface detachment which is supported by numerical findings. Microstructural changes during heating and cooling in form of crack formation occur in the metallic phase and metallic precipitation. The influence of the microstructural processes on the thermal expansion behavior are discussed in comparison to existing hypotheses from literature. [ABSTRACT FROM AUTHOR]

• First data on thermal properties of Ca 2 MH 7 (PO 4) 4 ·2H 2 O (M = K+,NH 4 +) and CaK 3 H(PO 4) 2. • Ca 2 MH 7 (PO 4) 4 ·2H 2 O (M = K+, NH 4 +) are stable up to 90 – 95 °C upon heating. • Ca 2 MH 7 (PO 4) 4 ·2H 2 O (M = K+, NH 4 +) undergo multi-step thermal decomposition. • CaK 3 H(PO 4) 2 exhibits very high thermal stability up to 530 °C. • Schemes of the thermal decompositions of the salts have been proposed. New knowledge about various aspects of little-known acid salts is of great scientific and practical importance in view of their potential application in different areas such as proton conductors. For the first time, the thermal behavior of three acid phosphate salts, dicalcium potassium heptahydrogen tetrakis(phosphate) dihydrate (Ca 2 KH 7 (PO 4) 4 ·2H 2 O), dicalcium ammonium heptahydrogen tetrakis(phosphate) dihydrate (Ca 2 (NH 4)H 7 (PO 4) 4 ·2H 2 O) and calcium tripotassium hydrogenbis(phosphate) (CaK 3 H(PO 4) 2), has been investigated. By means of simultaneous thermogravimetry, differential thermal and mass spectrometry analyses (TG/DTA/MS) the schemes of their thermal decomposition have been proposed. The two isostructural compounds Ca 2 KH 7 (PO 4) 4 ·2H 2 O and Ca 2 (NH 4)H 7 (PO 4) 4 ·2H 2 O are stable up to 90 – 95 °C and then undergo multiple-steps thermal decomposition process owing to dehydration of the crystallization water and dehydration-condensation. The anhydrous salt CaK 3 H(PO 4) 2 exhibits very high thermal stability up to 530 °C. The products of the thermal decomposition have been identified. [ABSTRACT FROM AUTHOR]

• DODAB and DODAC vesicles in aqueous solution can be prepared by spontaneous method. • The properties of DODAB and DODAC vesicles depend on concentration and counterion. • In water, at 1–20 mM, DODAB bilayer structures are more complex than those of DODAC. Cationic dioctadecyldimethylammonium bromide and chloride (DODAB and DODAC) lipids assemble in water as unilamellar vesicles or more complex bilayer structures depending on the lipid concentration, counter-ion, solvent characteristics, etc. By using differential scanning calorimetry (DSC) and cryogenic transmission electron microscopy (cryo-TEM) techniques we investigated the structural and thermal properties of these two widely investigated molecules at 1–20 mM in water. Changes in the DSC thermogram profile indicate that DODAB bilayers undergo more structural changes than DODAC, while Cryo-TEM micrographs show that, in this range of concentration, DODAB assembles as more complex bilayer structures than DODAC, which assemble predominantly as unilamellar vesicles. These findings thus indicate that DODAC is preferable to DODAB at 1–20 mM for the preparation of unilamellar vesicles. [Display omitted] [ABSTRACT FROM AUTHOR]

The effect of nano-confinement on the phase transitions of heneicosane ( n -C 21 H 44 , C 21 ) were investigated using differential scanning calorimetry (DSC) and variable temperature powder X-ray diffraction (XRD). When C 21 is confined within the pores of controlled pore glasses (CPGs), SBA-15 or other mesoporous materials, the solid-solid ( T s ) and solid-liquid ( T m ) transition temperatures are depressed. The depression of the phase transition temperatures (Δ T s , Δ T m ) for C 21 in CPGs and SBA-15, the degree of supercooling and enthalpy change (Δ H s , Δ H m ) for C 21 in CPGs, exhibited a linear dependence on the inverse pore size. The Δ T m values were insensitive to the polarity pore wall but varied with the pore geometry. XRD analysis revealed that the lamellar ordering characteristic for the solid C 21 was disturbed in the nanopores, with the extent increasing as the pore size decreased. A new rotator phase R II is found for C 21 confined in CPG (12 nm) and SBA-15 (14.4 nm). [ABSTRACT FROM AUTHOR]

Starch blends is an alternative method for achieving new technological properties, avoiding the use of chemical, modifications. Starches from pea (PS), rice (RS) and arracacha (AS) were mixed in different ratios utilizing simplex-centroid design, in order to evaluate the impact of these combinations on thermal, pasting and structural properties. It was established a maximum limit of 100% and minimum of 0% for each of the studied starches. Differential scanning calorimetry analysis show an increase on gelatinization temperatures ( T o , T p and T c ), when elevated RS concentrations. Furthermore, these parameters decreased with higher AS ratios. Thermogravimetric curves exhibited three characteristic mass losses. Stability increase was evidenced during dehydration in the interaction between starches, showing additive behavior between the studied samples. It was showed through viscoamilograms (RVA) an increase in peak viscosity, related to high AS ratios. The mixtures application was fundamental for the detection of synergistic or additive effects among the starches. [ABSTRACT FROM AUTHOR]

New thermal energy storage materials were developed as poly(acrylonitrile) (PAN) nanofibers with encapsulated phase change materials (PCMs). Sixteen samples composed of PAN shells and PEG or PEGME cores, and one control sample composed of only a PAN shell, were manufactured by coaxial electrospinning. SEM images revealed the formation of randomly distributed, distinct nanofibers with smooth surfaces and cylindrical shapes along their lengths. FTIR results confirmed bicomponent nanofiber structures and TGA results demonstrated their thermal stabilities. Phase change performances of nanofibers were repeatedly examined by DSC analyzes; heating enthalpies ranged from 38 to 133 J g −1 and from 29 to 60 J g −1 for PAN-PEGs and PAN-PEGME samples, respectively, corresponding to good encapsulation efficiencies. These remarkable thermal energy storages were achieved at different melting temperatures (−1 to 60 °C). Textile based sandwich structures containing three different types of PAN-PCM nanowebs demonstrated enhanced thermal properties and buffering function against temperature changes in surrounding. [ABSTRACT FROM AUTHOR]

In this study, the effects of sulfonated poly (styrene-divinylbenzene) (SP(St-DVB)) microspheres on the thermal curing of bisphenol A-based benzoxazine (Ba) was studied by preparing resin systems consisting of Ba and SP(St-DVB) microspheres. The thermal curing behavior and mechanism of Ba/SP(St-DVB) systems were investigated by differential scanning calorimetry and in situ Fourier transform infrared spectroscopy. The curing kinetics of Ba and Ba/SP(St-DVB) systems were investigated by non-isothermal DSC. The apparent activation energy of Ba and Ba/SP(St-DVB) systems gradually increased with the reaction extent (α). The dynamic mechanical analysis indicated that the glass transition temperatures of PBa/SP(St-DVB) composites did not decrease. The improved thermal stability of PBa/SP(St-DVB) composites was investigated by thermogravimetric analysis in the air and nitrogen atmosphere, respectively. The images of the fracture surfaces for PBa and PBa/SP(St-DVB) composites were investigated by scanning electron microscopy, demonstrating improved toughness of PBa/SP(St-DVB) composites. [ABSTRACT FROM AUTHOR]

The thermal expansion and heat capacity of coarse-crystalline (bulk) and nanocrystalline silver sulfide Ag 2 S have been studied by dilatometry and differential scanning calorimetry methods in the temperature interval from 290 to 970 K. The thermal expansion coefficient and heat capacity of nanocrystalline silver sulfide in the examined temperature range are larger than the same properties of coarse-crystalline sulfide. It is shown that these differences are due to a small particle size which leads to the restriction of the phonon spectrum on the side of low and high frequencies. It is established that the acanthite α-Ag 2 S to argentite β -Ag 2 S and argentite β -Ag 2 S to γ -Ag 2 S phase transformations are the first-order phase transitions, and the temperatures and enthalpies of these transformations have been determined. [ABSTRACT FROM AUTHOR]

Phase equilibrium theory and the laws of thermodynamics provide valuable tools for predicting the composition and the thermal properties of eutectic mixtures. In this work, we briefly review the predictions based on ideal mixtures. We evaluate the accuracy of the models by comparing the predicted values of the composition, the melting temperature ( T mpt ) and the enthalpy change (Δ fus H ) of binary mixtures of fatty acid phase change materials (PCMs), specifically as measured for decanoic – tetradecanoic acids, and dodecanoic – tetradecanoic acids and with values reported in the literature for other fatty acid eutectics. Although the phase diagrams depart from the ideal system (e.g., peritectic), there is, overall, reasonable agreement with the experimental data, i.e., the thermodynamic models can be a good starting point for the prediction of eutectic behaviour in binary or higher order mixtures of organic PCMs. A computational tool based on these thermodynamic models was developed in Microsoft Excel ® Kahwaji and White, [1] and used to calculate the composition, T mpt and Δ fus H of a total of 105 binary mixtures formed from 15 different fatty acid PCMs. The calculated properties show that eutectics both extend the lower range of T mpt and provide a wide range of new T mpt values that are not otherwise available from individual fatty acids, hence considerably expanding the scope of applications of fatty acids as PCMs for thermal energy storage. [ABSTRACT FROM AUTHOR]

In this study, novel nanowebs provided with thermal buffering properties were developed via coaxial electrospinning. Environmental friendly and nontoxic dialkyl and dialkenyl carbonates (DACs), namely, didecyl carbonate, didodecyl carbonate, ditetradecyl carbonate, dihexadecyl carbonate, dioctadecyl carbonate and dioleyl carbonate were synthesized from their fatty alcohols based on carbonate interchange reaction. Then the DAC-PMEA nanowebs were produced using 10–50 w% DAC in 3:1 chloroform-ethanol solution as core and 15 w% poly(methyl ethylacrylate) (PMEA)in ethanol as shell by coaxial electrospinning. The SEM images of the nanowebs presented randomly oriented, ultrafine fibers identified with smooth surfaces, continuous and cylindrical shapes. The nanowebs were able to provide considerable enthalpies (40–100 J g −1 ) during their repeated phase changes, up to hundred heating-cooling cycles, corresponding to 52–92% efficiencies obtained from electrospinning. These shape stabilized, lightweight DAC-PMEA nanowebs showed a significant potential for the dynamic thermal insulation applications across various industries, especially for the protection of temperature sensitive materials. [ABSTRACT FROM AUTHOR]

In this work, thermal characterization of centrifuged aromatic citrus oils was studied using thermal lens (TL) and open photoacoustic cell (OPC). The thermal diffusivity ( D ) was obtained by TL, fitting the critical time parameter of the experimental curves to the theoretical values. An experimental arrangement of non-matched mode lasers with a probe and an excitation lasers was used. On the other hand, the thermal effusivity ( e ) of the samples was obtained by using OPC. The thermal conductivity ( k ) was calculated from the relationship between D and e . The thermal parameters obtained were compared with theoretical values ​​in the literature. UV–vis spectroscopy, Attenuated Total Reflectance-Fourier Transform Infrared spectroscopy (ATR-FTIR) and 1 H Nuclear Magnetic Resonance (NMR) were used to determine the absorption coefficients and chemical structure of the citrus oils. The importance of this research work was the determination of the thermal parameters of essential oils as an alternative technique for quality control application. [ABSTRACT FROM AUTHOR]

In this work, poly(butylene succinate) (PBS), which is a well-established aliphatic polyester with excellent mechanical and thermal properties, was copolymerized with 2,5-furan dicarboxylic acid (FCDA) by melt polycondensation, for the formation of a poly(butylene succinate- co -furanoate) (PBSF) copolymer. The structural characteristics of the copolymer (PBSF) and both homopolymers (PBS, poly(butylene furanoate) − PBF) were studied by both wide angle X-ray diffraction (WAXD), while polarized light optical microscopy (PLOM) was utilized for the study of the spherulites grown at different temperatures. Differential scanning calorimetry (DSC) was used extensively for the evaluation of the thermal characteristics of the copolymer. The melting temperature and the glass transition of PBSF were observed at 106 °C and −29 °C respectively, while a depression of the melting point was also observed, compared to the homopolymers. The crystallization kinetics of the copolymer under isothermal and dynamic conditions were also studied using the Lauritzen–Hoffman and Avrami models. [ABSTRACT FROM AUTHOR]

Ethylene-octene copolymer (EOC)/organically modified Montmorillonite (OMMT) nanocomposites were prepared by melt mixing method in an internal mixer. The nanocomposites were then dynamically cross-linked with 0.25, 0.5, 0.75 and 1 wt% dicumyl peroxide (DCP). The results of low angle X-ray diffraction and transmission electron microscopy (TEM) micrographs demonstrated that the OMMT platelets were mainly intercalated by EOC. According to our findings, a mechanism has been proposed for the separation of OMMT layers from each other upon cross-linking. Thermogravimetric analysis (TGA) showed that the OMMT incorporation enhanced the thermal degradation of EOC. A schematic diagram was also prepared to show the main steps of EOC and the nanocomposites degradation with temperature under N 2 and air atmospheres. Moreover, it was found from the rheological results that all of the cross-linked nanocomposites behaved as shear thinning fluids over the entire range of frequency. The molecular weight between cross-links (M c ) was estimated using James-Guth as well as Mooney-Rivlin theory. The results indicated that M c decreased with increasing of the curing agent. [ABSTRACT FROM AUTHOR]

In this paper, a new type of microcapsulated phase change materials (BS-TD/PALMA microPCMs) with butylstearate (BS) and tetradecanol (TD) as binary cores and poly (allyl methacrylate) (PALMA) as shell, was prepared for thermo-regulated fibers. The surface morphology, particle size distribution, thermal properties and thermal stability of the resulting microcapsules were investigated. The results showed that the melting temperature and mean diameter of BS-TD/PALMA microPCMs were 20.1-32.6 °C and 1.3 ± 0.3 μm, respectively. The latent heat and encapsulation efficiency reached up to 73.3 J g −1 and 76.4 wt.%, respectively. BS-TD/PALMA microPCMs displayed good thermal stability. They were greatly favorable for the application to thermo-regulated fibers. [ABSTRACT FROM AUTHOR]

Whereas previous researchers analyzed the thermal behavior of paraffin waxes impregnated with graphene oxide nanoparticles (P-GONP) at high mass fraction ( > 1%), this paper analyzes behavior and stability at only 0.3% mass fraction. GONP was prepared by Hummer’s method. The morphology was studied using scanning electron microscope (SEM), transmission electron microscope (TEM), X-Ray diffraction (XRD) and Fourier Transformation-Infrared (FT-IR) Spectrometer and the thermal properties were measured using laser flash analyser (LFA), differential scanning calorimetry (DSC), thermo-gravimetric analysis (TGA) and thermal cycling. LFA showed a 101.2% and 94.5% increase in the thermal conductivity of P-GONP compared to pure paraffin (P) in solid and liquid state respectively. Melting and solidifying temperatures and latent heat were found to be 63.5, 59 °C & 102 kJ/kg and 57.5, 56 °C & 64.7 kJ/kg for P and P-GONP respectively. Thermal cycling over 4000 cycles showed that P-GONP was 27% more stable than P. The latent heat was 64.7 kJ/kg, a 36.5% deterioration compared to virgin paraffin. Compared against higher mass fraction impregnation, lower mass fraction P-GONP was found to have almost equivalent thermo-physical properties (namely thermal conductivity, melting and solidifying characteristics, thermo-chemical stability and reliability) while providing considerable cost saving. [ABSTRACT FROM AUTHOR]

Many efforts were made during the last years to utilize the superior properties of metallic glasses as reinforcements in metal matrix composites and several investigations were carried out to characterize composites’ mechanical properties. Since there is a complete lack of knowledge about their thermal properties, this work focuses on the thermal expansion behavior of metallic glass reinforced metal matrix composites produced via gas pressure infiltration. The aluminum alloy AlSi12 was used as matrix material. Metallic glass Ni 60 Nb 20 Ta 20 flakes with different size ranges were taken as reinforcement and volume fractions in the range of 29–44% were studied. X-ray micro computed tomography (μCT) measurements were performed to investigate the reinforcement 3D-structure within the composite. The thermal expansion behavior depending on flake orientation within the composite was investigated by dilatometric measurements. Four thermal cycles were carried out between room temperature and 500 °C at a constant heating and cooling rate of 5 °C/min. Results show that thermal strain rather depends on flake size and orientation than on volume fraction. Further, the composites exhibit a distinct anisotropic behavior for the thermal expansion coefficient (CTE) due to a layered flake structure within the composite. Finally determined CTEs were compared with several thermo-mechanical models to study the underlying mechanisms of the composite behavior. [ABSTRACT FROM AUTHOR]

The morphology and properties of blends of PP/HDPE and MAPP/HDPE blends, and their composites with wood powder, were investigated in this paper. The blends showed two-phase morphologies, and MAPP interacted better than PP with HDPE, while the WP interacted more strongly with MAPP. Although the different components in the blends were immiscible, they showed one crystallization peak. MAPP and HDPE showed separate crystallization peaks in the composites, and this separation of the crystallization became more resolved with increasing WP content and at lower cooling rates. This was also observed for PP and HDPE in their composites, but to a lesser extent. Young’s modulus increased and the stress at break decreased with increasing WP content, and these were more pronounced in the PP/HDPE/WP composites. Interaction between WP and MAPP also had an influence on elongation at break. The presence of WP increased the thermal stability of the MAPP/HDPE and PP/HDPE. [ABSTRACT FROM AUTHOR]

SiO 2 /SiC core-shell hybrid was prepared by oxidation of silicon carbide fibers. The material was thermally oxidized to observe the oxidation layer on the surface of the silicon carbide. The electrical and thermal properties of the epoxy composites consisting of SiC or SiO 2 /SiC were investigated. The thermal conductivity of SiO 2 /SiC-epoxy composites increased with increasing oxidation temperature. The thermal conductivity of the SiO 2 /SiC-epoxy composite was higher than that of the SiC-epoxy composite. The surface resistance and breakdown strength of the epoxy composite containing SiO 2 /SiC increased after the thermal oxidation of SiC. The developed SiO 2 /SiC could be used for electronic packaging applications. [ABSTRACT FROM AUTHOR]

In this study, we adopted the organic precursor thermal decomposition method to prepare Cu 2 O-Cu-MWCNTs/paraffin light-thermal conversion phase change material via one-step. The phase, micro morphology, phase change behavior, thermal reliability and thermal stability of the products were respectively characterized by XRD, SEM, DSC and TGA. We also investigated their light-thermal conversion properties. The results indicated when the content of precursor was 0.005 mol and 0.01 mol, the average particles size of hybird particles (Cu and Cu 2 O) were 30 nm and 400 nm, respectively. It was also found that the light-heat conversion performance of Cu 2 O-Cu-MWCNTs/paraffin were better than that of MWCNTs/paraffin with the same mass fraction. After we conducted analyses of UV–vis diffuse reflection spectra and thermal conductivity, We attributed the better light-heat conversion performance of Cu 2 O-Cu-MWCNTs/paraffin to the high light absorption ability of Cu 2 O and the reduction of interface thermal resistance between MWCNTs and paraffinresulting from Cu and Cu 2 O decorated MWCNTs. [ABSTRACT FROM AUTHOR]

Energy storage is a key challenge to a sustainable energy supply. To design new storage systems accurate and representative thermal property measurements are essential. The T- history method is quick and uncomplicated, however numerous adaptations have been proposed over the years. In this study these methods have been classified and critically assessed based on their mathematical formulation and experimental configuration. They can be broadly categorized according to one of three assumptions regarding the heat transfer coefficient for natural convection: it is constant either as a function of time or temperature, or it is negligible. This work proves in addition that the heat transfer coefficient for natural convection, varies both as a function of time and temperature. This is demonstrated both experimentally and through rigorous simulation of the proposed configurations. Thus T- history methods which show the most promise for precise and unambiguous measurements eliminate convection by making conduction the dominant thermal resistance in the system. These techniques can be tailored to different materials and do not require a simultaneous reference due to the use of a rigorous fundamental model compared to the lumped parameter approximation. The addition of heat flux sensors to quantify actual heat losses is recommended for absolute measurement certainty. [ABSTRACT FROM AUTHOR]

• Ordered mesoporous silica was prepared from cheap fly ash with a large suface area. • Shape-stabilized capacity of silica matrix to polyethylene glycol is up to 90 wt%. • Shape-stabilized phase change material has a high heat storage efficiency of 90%. • Aminoated multi–walled carbon nanotubes enhance the thermal conductivity by 191.3%. • Composite phase change materials exhibit excellent thermal enthalpy and reliability. Aiming at the problems of easy leakage and low thermal conductivity of solid–liquid phase change materials (PCM), and the recycle of fly ash, ordered mesoporous silica (OMS) was synthesized from fly ash to prepare the shape–stabilized PCM (SSPCM) with various polyethylene glycol (PEG) mass fractions. Aminoated multi–walled carbon nanotubes (MWNT–NH 2) were added into SSPCM for enhancing the heat transfer rate. The structure of PEG remains intact after blending with OMS. The shape–stabilization capacity of OMS to PEG was up to 90 wt%. The leakage problem of solid–liquid PCM can be effectively solved owing to the interactions between OMS and PEG, such as surface adsorption, mesoporous confinement and hydrogen bonding. The melting enthalpy of PEG/OMS SSPCM with 90 wt% PEG reaches up to 133.7 J g −1, and its heat storage efficiency is 90%. SSPCM exhibits excellent thermal stability and reliability. Its thermal conductivity is increased by 191.3% upon the addition of 5 wt% MWNT–NH 2 comparing with PEG. [Display omitted] [ABSTRACT FROM AUTHOR]

• Laboratory measurements of temperature-dependent rock thermal parameters for engineering applications. • Research works and correlations reported on rocks thermal properties are reviewed. • Methods for determining rock thermal properties from physical and chemical parameters. • Sample and inexpensive apparatus for determining thermal conductivity at room temperature. • Thermal conductivity and thermal diffusivity decrease and specific heat capacity increases with temperature. The rock thermal parameters is of basic interest in geophysical, underground and engineering applications. The most relevant properties are thermal conductivity, specific heat capacity and thermal diffusivity. The present paper focuses on thermal properties of several rock types and minerals under the influence of temperature. On one hand, we provide a detailed review of rock thermal parameters and available correlations, and on the other hand, a series of laboratory measurements are presented and data are analyzed. For specific heat capacity measurements at atmospheric pressure and over a temperature range from 20 to 600 °C, the Differential Scanning Calorimetry (DSC) method is used and an indirect method is proposed. The results demonstrated an increase of specific heat capacity with a second order polynomial regression. The thermal conductivity and thermal diffusivity were investigated between 20 and 180 °C using the Hot Disk method. A logarithmic decrease with temperature was observed. In addition, a simple and inexpensive apparatus for measuring thermal conductivity at room temperature (20.0 ± 0.2 °C) is described and the results are compared with the commercial device. The results showed good performance with the estimated errors below 10%. To improve the applicability of the obtained results, empirical equations are developed to predict the thermal properties as a function of temperature and other physical properties. It was observed that the empirical relationships and the predicted values by the proposed equations are in agreement with the experimental data and with literature. Research results in this paper can be used as a support for rock engineering and a solution of a range of scientific and applied problems. [ABSTRACT FROM AUTHOR]

• The kinetics of curing were studied and curing mode was found to be autocatalysis. • Polybismaleimide has high carbon residue rate of 68% at 800°C. • Polybismaleimide intelligently converts to polybenzoxazole at high temperature. • Polybismaleimide has excellent flame-retardant property. • Novel bismaleimide monomers have excellent solubility in various solvents. In this work, three bismaleimides containing cardo and ortho -oxazine structures, with dual advantages of bismaleimide and benzoxazine resin, were synthesized. Their chemical structures were characterized by Fourier transform infrared (FT-IR) spectroscopy and nuclear magnetic resonance (NMR) spectroscopy. The kinetics of curing and kinetic model were investigated by non-isothermal differential scanning calorimetry. The curing reaction of the bismaleimide was studied by in-situ FT-IR spectroscopy. Studies showed that both bismaleimide and benzoxazine provided the new structure with better thermal stability and solubility, compared to similar type of materials and commercial bismaleimides. Additionally, the further thermal rearrangement of the internal structure of the polymer at high temperature formed a benzoxazole structure with higher thermal stability. The rearrangement due to thermal changes was confirmed by in-situ FT-IR and solid-state 13C-NMR spectroscopy. Microscale combustion calorimetry (MCC) showed that both, bismaleimide and benzoxazole resins, were formed after thermal rearrangement and had excellent flame-retardant properties. [Display omitted] [ABSTRACT FROM AUTHOR]

• Temperature treatment cause obvious decrease in the P-wave velocity, density, thermal conductivity, and thermal diffusivity of the granite specimens. • Degradation of granite thermal properties is caused by thermal microcracks. • There is an obvious correlation between physical properties and the thermal conductivity or thermal diffusivity of the granite specimens, while the volumetric specific heat capacity of the specimens is opposite. In this work, thermal properties (thermal conductivity (k), thermal diffusivity (λ) and volumetric specific heat capacity (C)) tests and physical properties (P-wave velocity (V P) and density (ρ)) tests were performed to assess the impact of cyclic thermal treatment on the thermal characteristics of granite. The key findings are as follows: (1) the k, λ, V P and ρ all deteriorate due to cyclic thermal treatment. Cyclic thermal treatment has a negligible effect on the C of granite, and there is no obvious relationship between cycles and C. (2) There is a good fitting relationship between the k or λ and the physical properties, which indicate physical attributes can be utilized to assess the thermal properties of granite. (3) The loss of various water, as well as the initiation and propagation of microcracks, are responsible for the deterioration of physical and thermal characteristics. [ABSTRACT FROM AUTHOR]

Investigations of the length changes upon heating and cooling due to thermal expansion alone or its combination with phase transformations are often investigated using dilatometry. In dilatometric measurements with high heating rates a large longitudinal temperature gradient within the sample hinders an accurate investigation of the physical effects. In this study we examine the longitudinal temperature gradient and its effect on the measured length change for a wide range of heating rates. Maximum temperature differences of 160 °C for a maximum temperature of 570 °C within the sample are measured. A correction method based on a numerical model of the dilatometric experiment is developed and tested. The presented method allows an accurate and flexible method for correcting the interfered length change and exact interpretation of dilatometric data for high heating rates and complex time temperature profiles. [ABSTRACT FROM AUTHOR]

Poly(ε-caprolactone) (PCL) nanocomposites with hybrid clay-supported carbon nanotubes (Clay-CNT) in concentrations 0.5, 1.0 and 2.5 wt% were prepared by melt mixing. Mechanical, structural and thermal properties of the nanocomposites were studied. All nanocomposites exhibited similar stress-strain patterns to those of neat PCL but, with increasing nanofiller content yield point and Young’s Modulus values increased, despite the absence of chemical interactions between PCL and Clay-CNT. It was also found that the crystallinity of the nanocomposites is the same as for neat PCL, but the nanofiller acts as nucleating agent which promotes the crystallization and also allows it to occur at higher temperatures. Thermal stability is instead negatively influenced by the nanofiller, since Clay-CNT catalyzes the decomposition of PCL at lower temperature. The monomer ε-caprolactone is the main decomposition product resulting from intramolecular esterification while cis -elimination at ester bonds (β-hydrogen bond scission) is favored at higher temperatures. [ABSTRACT FROM AUTHOR]

The in-situ fabricated Al 2 O 3 /SiO 2(p) /Al composites were produced by adding different quantities of SiO 2 particles (viz. 0, 3, 6 and 9 wt.%) into molten commercial purity Al at 750 °C. Newtonian thermal analysis was conducted to investigate the solidification behaviors of these molten composites prepared by the stir casting process. The microstructure and phase identification were achieved via optical microscope, SEM (equipped with EDS) and X-ray diffraction. Results showed the dendrite arm spacing of α-Al grain decreased with the increase of SiO 2 addition. The SEM image showed the special duplex phase with Al 2 O 3 layer formed around SiO 2 particle in Al matrix. The Si concentration in Al matrix increased with increasing in the SiO 2 addition, resulting in the decrease of liquidus temperature of the melts. Compared with the purity Al melt, one more stage related to the exothermic Al-Si phase transformation was revealed in the cooling curves of these molten composites. Cooling rate of the purity Al melt was lower than that of the melts with SiO 2 particles addition. The difference in solidification behaviors of these melts was ascribed to the effect of SiO 2 /Al reaction on the effective heat capacity and different amounts of latent heat released from phase transformation process. [ABSTRACT FROM AUTHOR]