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This comprehensive research explores the starch isolated from four browntop millet cultivars to determine physicochemical, thermal, morphological, powder flow, pasting, and rheological properties. Significant variations (p ≤ 0.05) were observed among the cultivars. Aerated bulk density (ABD) and Tapped bulk density (TBD) values ranged from 0.476 g/mL (BTM4) to 0.591 g/mL (BTM1), and 0.591 g/mL (BTM1) to 0.476 g/mL (BTM4). Amylose content varied from 22.55% (BTM4) to 25.86% (BTM3), influencing gelling strength and film-forming properties. Water absorption capacity ranged from 1.78 g/g to 1.92 g/g, while oil absorption capacity varied from 2.20 g/g to 2.47 g/g. DSC analysis showed gelatinization temperatures (Tp, and Tc) ranging from 85.44-91.61 °C, and 147.08-154.21 °C, respectively. X-ray diffraction (XRD) patterns revealed A-type crystalline patterns, with relative crystallinity ranging from 22.66% (BTM3) to 27.81% (BTM2). Pasting properties exhibited variations among cultivars, with peak viscosity ranging from 2480 c P to 3119 cP, and pasting temperature from 77.50 °C to 82.35 °C. Rheological analysis indicated shear-thinning behavior. The findings offer insights into the diverse properties of browntop millet starch, contributing to its potential applications in various industries and potentially guiding future studies on browntop millet starch modifications and novel utilization., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The chitosan (CS) transparent film has attracted much attention in food and medicine packaging areas due to their biodegradability and good availability. A novel carbon quantum dots compound containing nitrogen and phosphorus (NP-CQDs) was obtained by reacting citric acids, with urea and phytic acids. The density of the film was increased, and the water vapor permeation was reduced by the presence of NP-CQDs. The introduction of 4 wt% NP-CQDs increased the water contact angle of the CS film from 79.2° to 105.8°. The shielding on UV-A and UV-B transmittance was increased with the NP-CQDs loading. The film containing 4 wt% NP-CQDs blocked more than 90.2% UV-A and 96.5% UV-B; however, it only blocked 26.8% visible light. It also exhibited better antibacterial activity to both E. coli and S. aureus than the control CS film. This work provided a feasible way to prepare multifunctional bio-safe film., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The popping process has been widely used as a technique for obtaining snacks. This study evaluated the effect of the popping process on the structural and thermal properties of sorghum. Seven varieties of sorghum were used. Raw sorghum grains were adjusted to 11% moisture and popped at 210 °C for 90 s with hot air. Microstructure, thermal and viscosity properties, and X-Ray and infrared spectrum were measured in raw and popped sorghum. The popping process produced an ordered honeycomb-like structure in the sorghum. The viscosity profile showed an increase in the thermal stability of popped sorghum. DSC measurements showed a starch gelatinization and a second transition about to 145 °C. XRD diffractograms display a reduction in the amplitude of the crystalline orthorhombic structure peaks. Finally, infrared indicated a change in the short-range structure and protein denaturation due to the popping process., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Electromagnetic-based hyperthermic therapies induce a controlled increase of temperature in a specific tissue target in order to increase the tissue perfusion or metabolism, or even to induce cell necrosis. These therapies require accurate knowledge of dielectric and thermal properties to optimise treatment plans. While dielectric properties have been well investigated, only a few studies have been conducted with the aim of understanding the changes of thermal properties as a function of temperature; i.e., thermal conductivity, volumetric heat capacity and thermal diffusivity. In this study, we experimentally investigate the thermal properties of ex vivo ovine liver in the hyperthermic temperature range, from 25 °C to 97 °C. A significant increase in thermal properties is observed only above 90 °C. An analytical model is developed to model the thermal properties as a function of temperature. Thermal properties are also investigated during the natural cooling of the heated tissue. A reversible phenomenon of the thermal properties is observed; during the cooling, thermal properties followed the same behaviour observed in the heating process. Additionally, tissue density and water content are evaluated at different temperatures. Density does not change with temperature; mass and volume losses change proportionally due to water vaporisation. A 30% water loss was observed above 90 °C.

Native sweet potato starch was gelatinized at temperatures between 57 and 69 °C and then spray dried, to verify the changes caused by this process. The spray dried starch granules initially swelled with the increase in preheating temperature, displaying a larger diameter, but shrank upon colling. There was an increase in the gelatinization temperature and a decrease in the enthalpy change of the spray dried starches relative to those of native starch. Spray dried starch preheating at 69 °C showed highly reduced enthalpy change (80%) and relative crystallinity. Based on the parameters studied, the best preheating temperature was 67 °C. Under this condition, the starch can be applied in more viscous products that require a greater thickness, and with great process yield (65%). This study showed the feasibility of the application of this process to produce sweet potato starches with specific properties for different purposes in the food and non-food industries., (Copyright © 2019 Elsevier B.V. All rights reserved.)

The modification of achira starch a thermoplastic biopolymer is shown. Glycerol and sorbitol, common plasticizers, were used in the molten state with organic acids such as oleic acid and lactic acid obtaining thermodynamically more stable products. The proportion of starch:plasticizer was 70:30, and the acid agent was added in portions from 3%, 6%, and 9% by weight. These mixtures were obtained in a torque rheometer for 10 min at 130 °C. The lactic acid managed to efficiently promote the gelatinization process by increasing the available polar sites towards the surface of the material; as a result, there were lower values in the contact angle, these results were corroborated with the analysis performed by differential scanning calorimetry and X-ray diffraction. The results derived from oscillatory rheological analysis had a viscous behavior in the thermoplastic starch samples and with the presence of acids; this behavior favors the transitions from viscous to elastic. The mixture of sorbitol or glycerol with lactic acid promoted lower values of the loss module, the storage module, and the complex viscosity, which means lower residual energy in the transition of the viscous state to the elastic state; this allows the compounds to be scaled to conventional polymer transformation processes.

Large and small granules were separated from C-type starches of four Chinese chestnut varieties growing in the same environment. They had similar amylose contents from 17.7% to 20.2% and showed C-type crystallinity. The large granules had relative crystallinity from 19.2% to 20.3%, ordered degree from 0.672 to 0.706, and lamellar peak intensity from 233.2 to 267.1, but small granules had relative crystallinity from 16.2% to 18.2%, ordered degree from 0.635 to 0.663, and lamellar peak intensity from 201.6 to 213.1. The gelatinization peak temperatures ranged from 62.6 to 65.7 °C in large granules but from 60.3 to 61.7 °C in small granules, and enthalpy variation did from 12.5 to 13.7 J/g in large granules but from 10.1 to 11.7 J/g in small granules. Both large and small granules showed biphasic hydrolysis. Though small granules had significantly higher hydrolysis rate than large granules, but they had similar total hydrolysis extent during whole hydrolysis. The granule size had significantly positive relationships with relative crystallinity, ordered degree, lamellar peak intensity, and gelatinization temperature and enthalpy variation, but was negatively correlated to hydrolysis rate. The principal component analysis was conducted to reveal the interrelationships among different starch properties and the variations among different starches., (Copyright © 2019 Elsevier B.V. All rights reserved.)

A native polysaccharide (RCPI) with sugar content of 79.94 ± 0.57% was isolated from raspberry fruits. A degraded polysaccharide (DRCPI) with sugar content of 83.82 ± 0.71% was obtained from the crude polysaccharides after degradation by Fe 2+ -H 2 O 2 treatment. The molecular weights of RCPI and DRCPI were determined to be 411,000 and 8010 Da, respectively. GC analysis revealed that both RCPI and DRCPI were composed of the same monosaccharides (rhamnose, arabinose, xylose, mannose, glucose, galactose, and galacturonic acid) in different molar ratios. IR and NMR spectroscopy confirmed that RCPI and DRCPI possessed similar structural characteristics, although DRCPI displayed higher antioxidant activities and greater thermal stability. Furthermore, DRCPI exhibited excellent rheological properties. These data provide evidence to support the application of raspberry-derived polysaccharides in functional foods., (Copyright © 2019. Published by Elsevier B.V.)

Determination of the thermal characteristics and temperature-dependent rheological properties of the magnetorheological elastomers (MREs) is of paramount importance particularly with regards to MRE applications. Hitherto, a paucity of temperature dependent analysis has been conducted by MRE researchers. In this study, an investigation on the thermal and rheological properties of epoxidized natural rubber (ENR)-based MREs was performed. Various percentages of carbonyl iron particles (CIPs) were blended with the ENR compound using a two roll-mill for the preparation of the ENR-based MRE samples. The morphological, elemental, and thermal analyses were performed before the rheological test. Several characterizations, as well as the effects of the strain amplitude, temperature, and magnetic field on the rheological properties of ENR-based MRE samples, were evaluated. The micrographs and elemental results were well-correlated regarding the CIP and Fe contents, and a uniform distribution of CIPs was achieved. The results of the thermal test indicated that the incorporation of CIPs enhanced the thermal stability of the ENR-based MREs. Based on the rheological analysis, the storage modulus and loss factor were dependent on the CIP content and strain amplitude. The effect of temperature on the rheological properties revealed that the stiffness of the ENR-based MREs was considered stable, and they were appropriate to be employed in the MRE devices exposed to high temperatures above 45 °C.

Fibrillar materials have gained much attention recently because of their unique properties and potential applications. Although many methods have been developed to fabricate materials, it remains challenging to prepare fibrillar materials containing multicomponent materials or even with complex structures. Here, a facile strategy is developed to fabricate bamboo-shaped fibers by treating electrospun polymer core-shell fibers with solvent vapor annealing. Electrospun polystyrene (PS)/poly(methyl methacrylate) (PMMA) core-shell fibers are first prepared by electrospinning PS/PMMA blend solutions via a phase separation process. When the PS/PMMA core-shell fibers are annealed with the vapor of cyclohexane, which swells and delocalizes the PS domains selectively, the fibers transform into bamboo-shaped structures. The bamboo-shaped structures can be further examined by swelling and delocalizing the PMMA domains selectively, revealing the undulated PS structures. The thermal insulation properties of the fibers with bamboo-shaped structures are observed to be enhanced compared with the original polymer core-shell fibers., (© 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

This study investigated the effect of different levels (4, 8 and 12%) of sucrose, isomalt and maltodextrin on the microstructural, water absorption, physico-chemical, thermal and textural characteristics of wheat and cassava starch gels, by scanning electron microscopy (SEM), rapid visco analysis (RVA), differential scanning calorimetry (DSC) and texture profile analysis. According to SEM analysis, cassava granules were more impressed than wheat starch in the presence of isomalt > sucrose > maltodextrin. Results showed that water absorption decreased when the amount of sucrose, isomalt and maltodextrin increased. In contrast, onset (T o ), peak (T p ) and conclusion (T c ) temperature, and enthalpy (ΔH) of wheat and cassava starch gels, increased as the level of addition increased. With increasing the sugar concentration, T o , T p , T c and ΔH gel enhanced significantly relative to the native starch. The polyols had more remarkable effects on the thermal properties of cassava starch than wheat starch. The texture of wheat and cassava starch gels incorporated with polyol sugars had solid-like properties. The gelatinization of starch was delayed more by isomalt than sucrose and maltodextrin. Moreover, the combination of principal component analysis and cluster analysis proved to be a suitable statistical approach to highlight the effect of adding varying levels of polyols to starch., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In this work, the influence of sorbitol content on the microstructure and thermal properties of chitosan films was investigated by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), Thermogravimetric analysis (TGA) and Differential scanning calorimetry (DSC). It showed that the addition of sorbitol weakened the hydrogen bonding between chitosan molecules as well as the electrostatic interactions existed in chitosan films. Structural analysis revealed that a small amount of sorbitol (~10 wt%) could facilitate the crystallization of chitosan, whereas it was seriously hindered at high content of sorbitol (~50 wt%). The thermal behavior of composite films indicated that the sorbitol addition did not reduce the thermal stability of polymer films. When the sorbitol content rose to above 30 wt%, phase separation may occur and two glass transitions presented in composite films. The lower temperature transition was associated with the glass-rubber transition of sorbitol-rich phase, and the higher one was related to chitosan-rich phase. These results implied that the microstructure as well as properties of the plasticized chitosan films can be controlled by adding sorbitol, which is important for their usage as packaging materials., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The aim is to develop novel synergistic transparent k-Carrageenan/Xanthan gum/Gellan gum (k-C/X/G) hydrogel films with different weight ratio composition and to study the effect of these compositions on the physical properties of the films. The structure and morphological properties of the films were investigated by Fourier-transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), X-ray diffraction (XRD) and differential scanning calorimeter (DSC). Results for FT-IR, DSC and SEM analysis showed a clear interaction between k-C, X, and G to form a new material. The mechanical, thermal and water barrier properties such as water vapor permeability (WVP), water contact angle (WCA) and moisture content were determined. The temperature at 5% weight loss (T 5% ) are in the range of 64.2-121.9 °C. The WVP exhibits are in the range of 1.8-2.4, contact angle are in the range of 32-65.8° and moisture content 16.5-21.51. The hydrogel film had good tensile strength of 19.1-31.0 MPa and elongation at break of 13-19% and tensile modulus of 1.6-2.4 GPa. The UV results indicate that the films were very transparent. The range of properties of the ternary k-C/X/G hydrogel films suggest that the presence molecular interaction and cross linking within the blends., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The BCNs were chemically modified using acetic anhydride with the aim of improving its dispersion and interfacial adhesion. Acetylation of BCNs was confirmed by FT-IR spectroscopy. Morphology studies using TEM and SEM revealed that a reasonable dispersion of the modified BCNs in the EVA matrix was accomplished. The DSC data displayed a little shift in the T g to higher temperatures with the incorporation of both modified and unmodified BCNs. Increased thermal stability of the nanocomposites consisting acetylated BCNs was confirmed by TGA technique. DMA measurements highlighted that the storage modulus increased and the damping properties decreased for the nanocomposites with regard to the neat EVA., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Soil burial degradation was confirmed to be an efficient waste disposal method for the biodegradable materials with short service life, such as starch/poly (lactic acid) (PLA) composite. The biodegradation behavior about chemical and thermal properties of starch/PLA composite was analyzed by using X-ray photoelectron spectroscopy (XPS), infrared microscopy (IRM), differential scanning calorimetry (DSC), and thermal gravimetric analysis (TGA). XPS and IRM results indicated that the biodegradation of PLA occurred at the ester groups in PLA chains. XPS demonstrated the cleavage of CO linkages between glucose rings in starch. DSC and TGA results showed that the starch/PLA composite degraded faster than the pure PLA. During the soil burial degradation, the glass transition temperature of starch/PLA composite exhibited an obviously decrease while it had a slight variation for PLA. The thermal stability of starch/PLA composite shifted towards to that of PLA when they were subjected to soil burial for the same time. It is established that the starch can accelerate the degradation of PLA-based materials, which will enlarge the markets of biodegradable PLA materials used for short service life products., (Copyright © 2018 Elsevier B.V. All rights reserved.)

The present work aims to evaluate the effect of an acid extraction as well as a combined enzymatic-chemical extraction on structural, thermal and antioxidant properties of the sulphated polysaccharide 'ulvan' from the green seaweed Ulva lactuca. Structural characterization by FTIR and NMR spectroscopies showed the typical peaks of ulvan, namely, uronic acids, rhamnose and sulphate. FTIR analysis revealed that the extraction procedures were able to maintain ulvan structure. Despite differences in the extraction procedures, 13 C NMR spectra were globally similar, proving a comparable chemical structure of ulvans. A major difference has been observed in signal intensity which reflected the resonance of glucose or xylose. Thermal characterization proved that ulvans were thermally stable until approximately 180°C. Antioxidant properties of ulvans were evaluated in vitro through different antioxidant assays. Ulvan, which is extracted at pH 1.5 and 90°C, exhibited the greatest scavenging activity (IC 50 =13.56μg/ml) towards DPPH radical. Result indicated that Mw has influenced inhibitory effect on DPPH radical of ulvan. The current study revealed also a high correlation between sulphate contents of ulvans and their reducing power (R 2 =-0.89) and their metal scavenging activity (R 2 =0.97). Overall, ulvans have peculiar structural, thermal and antioxidant properties which promote their use in food or pharmaceutical products as natural ingredient., (Copyright © 2017 Elsevier B.V. All rights reserved.)

In this study starches isolated from Indian quinoa varieties were examined for physicochemical, morphological, thermal and rheological properties. Among isolated starches V 1 showed higher starch yield and lower purity (48.45% and 98.32%) than V 2 (41.28 and 98.53%). The amylose content was higher for V 1 (12.10%) than V 2 (9.46%). Swelling powers and solubility of the starches increased with increasing temperature. Peak viscosity (386.4 RVU) was higher for V 1 . In contrast V 2 showed higher pasting temperature (72.85°C). Low setback viscosity of the starches suggests that they can be profitably used in frozen and refrigerated foods. Starch granules from both varieties were irregular, angular and polygonal in shape. The starch granule size obtained by SEM was 1.23μm for V 1 and 1.19μm for V 2 . Both starches showed a typical A-type diffractrometric pattern with varying crystallinity. Further V 1 showed lower transition temperatures (To, Tp and Tc) than V 2 . FTIR spectroscopy showed higher intensity and broader shape of V 2 at OH stretch which can be due to its higher crystallinity. Increased interest is shown in quinoa starch because of its unique microcrystalline granules. Higher yield and purity values suggest that both varieties can be exploited for commercial starch utilization., (Copyright © 2017 Elsevier B.V. All rights reserved.)

A hybrid composite was prepared from cassava bagasse (CB) and sugar palm fiber (SPF) using casting technique with cassava starch (CS) as matrix and fructose as a plasticizer. Different loadings of SPF (2, 4, 6 and 8% w/w of dry starch) were added to the CS/CB composite film containing 6% CB. The addition of SPF significantly influenced the physical properties. It increased the thickness while decreasing the density, water content, water solubility and water absorption. However, no significant effect was noticed on the thermal properties of the hybrid composite film. The incorporation of SPF increased the relative crystallinity up to 47%, compared to 32% of the CS film. SEM micrographs indicated that the filler was incorporated in the matrix. The film with a higher concentration of SPF (CS-CB/SPF8) showed a more heterogeneous surface. It could be concluded that the incorporation of SPF led to changes in cassava starch film properties, potentially affecting the film performances., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Given their amphiphilic nature and chemical structure, phospholipids exhibit a strong thermotropic and lyotropic phase behaviour in an aqueous environment. Around the phase transition temperature, phospholipids transform from a gel-like state to a fluid crystalline structure. In this transition, many key characteristics of the lipid bilayers such as structure and thermal properties alter. In this study, we employed atomistic simulation techniques to study the structure and underlying mechanisms of heat transfer in dipalmitoylphosphatidylcholine (DPPC) lipid bilayers around the fluid-gel phase transformation. To investigate this phenomenon, we performed non-equilibrium molecular dynamics simulations for a range of different temperature gradients. The results show that the thermal properties of the DPPC bilayer are highly dependent on the temperature gradient. Higher temperature gradients cause an increase in the thermal conductivity of the DPPC lipid bilayer. We also found that the thermal conductivity of DPPC is lowest at the transition temperature whereby one lipid leaflet is in the gel phase and the other is in the liquid crystalline phase. This is essentially related to a growth in thermal resistance between the two leaflets of lipid at the transition temperature. These results provide significant new insights into developing new thermal insulation for engineering applications., (© 2017 The Authors.)

The structure and surface properties of binary and ternary blends containing collagen (Coll), hyaluronic acid (HA) and chitosan (Ch) were investigated by contact angle measurements, thermogravimetric analysis (TGA), scanning electron microscopy (SEM) and atomic force microscopy (AFM). Thin films of Coll/HA and Coll/HA/Ch blends have been formed by casting methods from aqueous acid solutions. The surface roughness, hydrophobic/hydrophilic character and thermal stability of Coll/HA were changed after addition of chitosan. Thermal stability of binary blends increase upon the addition of chitosan. The results of contact angle and the surface free energy revealed that hyaluronic acid films are more polar than collagen and chitosan films. The surface energy and its polar and dispersive components of binary and ternary blends were calculated and more hydrophilic films were produced by the addition of HA and chitosan, also resulting in more thermally stabile materials. These results demonstrate that collagen interacts with hyaluronic acid and chitosan changing the surface properties of polymer films., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Thermo-mechanical properties of boron nitride nanoribbons (BNNRs) were computed using molecular dynamics simulation with optimized Tersoff empirical potential. Thermal conductivity (TC) and heat transport properties of BNNRs were calculated as functions of both temperature and nanoribbon's length. The results show that TC of BNNRs decreases with raising temperature by T(-1.5) up to 1000K. The phonon-phonon scattering relaxation time, mean free path of phonons, and contribution of high frequency optical phonons in TC of BNNRs were calculated at various temperatures. TC decreases as nanoribbon size increases and it converges to ∼500Wm(-1)K(-1) for nanoribbons with length longer than 30nm. The mechanical properties, including Gruneisen parameter, stress-strain response curves, Young's modulus, intrinsic strength, critical strain, and poisson's ratio were calculated in the temperature range of 137-1000K. The simulation results show that Gruneisen parameter and poisson's ratio of BNNRs are -0.092 and 0.245, respectively. The Young's modulus of BNNRs decreases with raising temperature and its value is 630GPa at 300K. According to the results, BNNRs duo to their extraordinary thermo-mechanical properties, are the promising candidate for the future nano-device manufacturing., (Copyright © 2016 Elsevier Inc. All rights reserved.)

This study aims at physicochemical properties of thermo- and pH/CO2 -responsive cyclic homopolymers. Three examples of cyclic poly(2-(dimethylamino)ethyl methacrylate)s (PDMAs) are synthesized by combining the reversible addition-fragmentation chain transfer process and the Diels-Alder ring-closure reaction. After cyclization, the glass transition temperature significantly increases (ΔTg = 51.8-59.7 °C) due to the different configurational entropy and end groups, and the maximum decomposition temperature to lose the pendent groups is drastically decreased from 309 to 278 °C. Effects of polymerization degree, polymer concentration, additive of NaCl, and pH/CO2 on lower critical solution temperature behaviors of PDMA aqueous solutions are investigated. The cloud points (Tc ) of ring PDMAs are usually higher than their linear precursors, and the ΔTc values obtained under a fixed condition can reach up to 20.7 °C, revealing the crucial role of the topology effect. This study paves the way for unique properties and applications of smart cyclic polymers and their derivatives., (© 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

In this study, new wood-inspired films were developed from microfibrillated cellulose and galactoglucomannan-lignin networks isolated from chemothermomechanical pulping side streams and cross-linked using laccase enzymes. To the best of our knowledge, this is the first time that cross-linked galactoglucomannan-lignin networks have been used for the potential development of composite films inspired by woody-cell wall formation. Their capability as polymeric matrices was assessed based on thermal, structural, mechanical and oxygen permeability analyses. The addition of different amounts of microfibrillated cellulose as a reinforcing agent and glycerol as a plasticizer on the film performances was evaluated. In general, an increase in microfibrillated cellulose resulted in a film with better thermal, mechanical and oxygen barrier performance. However, the presence of glycerol decreased the thermal stability, stiffness and oxygen barrier properties of the films but improved their elongation. Therefore, depending on the application, the film properties can be tailored by adjusting the amounts of reinforcing agent and plasticizer in the film formulation., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In view of their complementary properties, blending polylactide (PLA) with poly (ε-caprolactone) (PCL) becomes a good choice to improve PLA's properties without compromising its biodegradability. A series of blends of biodegradable PLA and PCL with different mass fraction were prepared by melt mixing. Standard tensile bars were produced by both conventional and microcellular injection molding to study their mechanical and thermal properties. With the increase in PCL content, the blend showed decreased tensile strength and modulus; however, elongation was dramatically increased. With the addition of PCL, the failure mode changed from brittle fracture of the neat PLA to ductile fracture of the blend as demonstrated by tensile test. Various theoretical models based on dispersion and interface adhesion were used to predict the Young's modulus and the results shows the experimental data are consistent with the predictions of the foam model and Kerner-Uemura-Takayangi model. The thermal behavior of the blends was investigated by DSC and TGA. The melting temperature and the degree of crystallinity of PCL in the PLA/PCL did not significantly change with the PCL content increasing in the whole range of blends composition., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The quality of sorghum grains can vary according to the conditions of the drying temperature and storage time. The objective of this study was to evaluate the effects of the drying temperature and storage time of sorghum grain on the structure and technological properties of starch. The sorghum grains were dried at 45, 65, and 85°C and stored for six months. The grains were stored in an environment with a controlled temperature and humidity, and the starch from sorghum grains was isolated in initial time, after three and six months. The sorghum starches grains dried at 45 and 65°C present higher relative crystallinity than the starches of sorghum grains dried at 85°C in three months of storage. A reduction in the solubility of the starches of the sorghum grains dried at 85°C was observed when the grains were stored during six months. The breakdown and swelling power of the starches were reduced with the increase of the drying temperature., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

Nanocellulosic materials with good thermal stability are highly desirable for applications, such as reinforcement and filler agents in composites. In the present work, phosphonated cellulose was utilized to obtain nanocelluloses with good thermal stability and potential intumescent properties. Phosphonated cellulose was synthetized from birch pulp via sequential periodate oxidation and reductive amination using a bisphosphonate group-containing amine, sodium alendronate, as a phosphonating reagent. After high-pressure homogenization, bisphosphonate cellulose nanofibres or nanocrystals were obtained, depending on the initial oxidation degree. Nanofibres had a typical diameter of 3.8nm and length of several micrometers, whereas nanocrystals exhibited a width of about 6nm and an average length of 103-129nm. All nanocelluloses exhibited cellulose I crystalline structures and high transparency in water solutions. Phosphonated nanocelluloses exhibited good thermal stability and a greater amount of residual char was formed at 700°C compared to birch pulp and mechanically produced, non-chemically modified NFC., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

The search for ideal biomaterials is still on-going for tissue regeneration. In this study, blends of poly ε-caprolactone (PCL) with poly l-lactic acid (PLLA), nalidixic acid (NA) and polyethylene glycol (PEG) were prepared. Mechanical and thermal properties of the blends were investigated by tensile and flexural analysis, DSC, TGA, WXRD, MFI, BET, SEM and hot stage optical microscopy. Results showed that the loading of PLLA caused a significant decrease in tensile strength and almost total eradication of the elongation at break of PCL matrix, especially after PEG and NA addition. Increased stiffness was also noted with additional NA, PEG and PLLA, resulting in an increase in the flexural modulus of the blends. Isothermal degradation indicated that bulk PCL, PLLA and the blends were thermally stable at 200°C for the duration of 2h making extrusion of the blends at this temperature viable. Morphological study showed that increasing the PLLA content and addition of the very low viscosity PEG and powder NA decreased the Melt Flow Indexer and increased the viscosity. At the higher temperature, the PLLA begins to soften and eventually melts allowing for increased flow and, coupling this with, the natural increase in MFI caused by temperature is enhanced further. The PEG and NA addition increased dramatically the pore volume which is important for cell growth and flow transport of nutrients and metabolic waste., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

In the present paper the results regarding the influence of UV-irradiation with 254 nm wavelength on the thermal and mechanical properties and the intrinsic viscosity of chitosan/silk fibroin mixtures are presented. The mixture of chitosan and silk fibroin in solution and thin films made of chitosan/silk fibroin mixture obtained by solvent evaporation were submitted to the treatment with UV irradiation (wavelength 254 nm) for different time intervals. Mechanical properties of thin films made of chitosan/silk fibroin blends before and after UV-irradiation have been investigated by mechanical testing machine and compared with mechanical properties of chitosan films. The changes in such mechanical properties as ultimate breaking strength, percentage of elongation at break and Young Modulus have been investigated. The results have shown, that the mechanical properties of the blends were greatly affected by time of exposure to UV irradiation. Ultimate tensile strength and ultimate percentage of elongation decreased after UV irradiation of the blend. Increasing UV irradiation led to the decrease in Young's Modulus of the chitosan/silk fibroin blend. Viscosity of chitosan/silk fibroin mixtures decreased after UV-irradiation. Thermal properties of the mixtures have been only slightly altered by UV-irradiation., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Cellulose nanocrystals (CNCs) synthesized from microcrystalline cellulose by acid hydrolysis were added into poly(lactic acid)-poly(hydroxybutyrate) (PLA-PHB) blends to improve the final properties of the multifunctional systems. CNC were also modified with a surfactant (CNCs) to increase the interfacial adhesion in the systems maintaining the thermal stability. Firstly, masterbatch pellets were obtained for each formulation to improve the dispersion of the cellulose structures in the PLA-PHB and then nanocomposite films were processed. The thermal stability as well as the morphological and structural properties of nanocomposites was investigated. While PHB increased the PLA crystallinity due to its nucleation effect, well dispersed CNC and CNCs not only increased the crystallinity but also improved the processability, the thermal stability and the interaction between both polymers especially in the case of the modified CNCs based PLA-PHB formulation. Likewise, CNCs were better dispersed in PLA-CNCs and PLA-PHB-CNCs, than CNC., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

18-crown-6 ether (18C6) complexes with the following anionic surfactants: sodium n-dodecylsulfate (18C6-NaDS), sodium 4-(1-pentylheptyl)benzenesulfonate (18C6-NaDBS); and potassium picrate (18C6-KP) were synthesized and studied in terms of their thermal and structural properties. Physico-chemical properties of new solid 1:1 coordination complexes were characterized by infrared (IR) spectroscopy, thermogravimetry and differential thermal analysis, differential scanning calorimetry, X-ray diffraction and microscopic observations. The strength of coordination between Na(+) and oxygen atoms of 18C6 ligand does not depend on anionic part of the surfactant, as established by thermodynamical parameters obtained by temperature-dependent IR spectroscopy. Each of these complexes exhibit different kinds of endothermic transitions in heating scan. Diffraction maxima obtained by SAXS and WAXS, refer the behavior of the compounds 18C6-NaDS and 18C6-NaDBS as smectic liquid crystalline. Distortion of 18C6-NaDS and 18C6-KP complexes occurs in two steps. Temperature of the decomplexation of solid crystal complex 18C6-KP is considerably higher than of mesophase complexes, 18C6-NaDS, and 18C6-NaDBS. The structural and liquid crystalline properties of novel 18-crown-ether complexes are function of anionic molecule geometry, type of chosen cation (Na(+), K(+)), as well as architecture of self-organized aggregates. A good combination of crown ether unit and amphiphile may provide a possibility for preparing new functionalized materials, opening the research field of ion complexation and of host-guest type behavior., (Copyright © 2013 Elsevier B.V. All rights reserved.)

Banana starches (BS) were isolated from Enano, Morado, Valery and Macho cultivars. The BS possessed B-type crystallinity and an amylose content varying from 19.32 to 26.35%. Granules had an oval morphology with different major-to-minor axis ratios, exhibiting both mono- and bi-modal distributions and mean particle sizes varying from 32.5 to 45 μm. BS displayed zeta-potential values ranging between -32.25 and -17.32 mV, and formed gels of incipient to moderate stability. The enthalpy of gelatinization of BS affected the crystalline order stability within the granules. In-vitro digestibility tests showed fractions as high as 68% of resistant starch. Rheological oscillatory tests at 1 Hz showed that BS dispersions (7.0%, w/w) exhibited Type III behaviour, attributed to the formation of a continuous phase complex three-dimensional amylose gel reinforced by swollen starch granules acting as fillers. Amylose content and granules morphology were the main factors influencing the BS properties., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Blending allows to tailor and modulate the properties of selected polymers. Blends of poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and polyethylene oxide (PEO) were fabricated by electrospinning in different weight ratios i.e. 100:0, 80:20, 70:30, 50:50, 0:100. In order to evaluate the influence of PEO addition on the final properties of PHBV, a complete microstructural, thermal and mechanical characterization of PHBV/PEO blends has been performed. The two neat polymeric membranes were also considered for the sake of comparison. The following characterization techniques were employed: scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), Fourier transform infrared attenuated total reflectance (FTIR-ATR) spectroscopy, simultaneous thermogravimetric and differential analyses (TG-DTA), differential scanning calorimetry (DSC), and uniaxial tensile tests. All electrospun mats consisted of randomly oriented and uniform fibers. It has been observed that the microstructure of PHBV/PEO was remarkably affected by blend composition. The average fiber size ranged between 0.5 μm and 2.6 μm. It resulted that the electrospun polymeric blends consisted of separate crystalline domains associated to an amorphous interdisperse phase. PHBV/PEO blends presented intermediate mechanical properties, in terms of tensile modulus and ultimate tensile stress, with respect to the two neat components., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The thermal effusivity of Al(2)O(3) and CuO nanofluids in different base fluids, i.e., deionized water, ethylene glycol and olive oil were investigated. The nanofluids, nanoparticles dispersed in base fluids; were prepared by mixing Al(2)O(3), CuO nanopowder and the base fluids using sonication with high-powered pulses to ensure a good uniform dispersion of nanoparticles in the base fluids. The morphology of the particles in the base fluids was investigated by transmission electron microscopy (TEM). In this study, a phase frequency scan of the front pyroelectric configuration technique, with a thermally thick PVDF pyroelectric sensor and sample, was used to measure the thermal effusivity of the prepared nanofluids. The experimental results of the thermal effusivity of the studied solvents (deionized water, ethylene glycol and olive oil) showed good agreement with literature values, and were reduced in the presence of nanoparticles. The thermal effusivity of the nanofluid was found to be particularly sensitive to its base fluid and the type of nanoparticles.

In the years 2022 and 2023 we investigated the prevalence of the ovulatory failure in 133 mares of different breed, 3 to 24 years old, brought to the Equine clinic of the University of Veterinary Medicine and Pharmacy (UVMP) in Košice. Our research involved the monitoring of the reproduction cycle in these mares with the aim to determine the prevalence of ovulatory failure during the breeding season, focusing on certain specific parameters that were considered sufficiently relevant with respect to the development of such failure. These parameters included environmental temperature and the amount of daylight the mares were exposed to, attributable to the months of the breeding season. In addition, we also evaluated the size of pre-ovulatory follicles and the influence of age of the investigated mares. During the mentioned years, one of the ovulatory failures occurred in 17 out of 133 mares (12.78 %). Examination by ultrasonography (USG) and the subsequent analysis of the occurrence of failures in relation to the investigated parameters allowed us to conclude that the length of daylight, age, and environmental temperature were the most important factors. Our observations indicated that the 15–16 h category of daylight presented the highest risk of development of cycle disorders with the most rapid increase observed for HAF. With respect to age, the highest occurrence of ovulatory failures was observed in the category of 15–24 years. The external temperature in the range of 18.1–23.0 °C affected the most the development of cycle disorders. Again, the effect was most evident with respect to HAF. This resulted in our recommendations for horse breeders that they should manage reproduction of their mares in a way so that the receptive phase of the cycle does not occur in the months during which the daylight length and environmental temperatures support ovulatory failure. We also recommend that if the owner′s wish is to keep in the breeding the mares older than 15 years, regular thorough gynaecological examination of these animals should be ensured, aimed at early diagnosis of ovulatory failure. [ABSTRACT FROM AUTHOR]

We investigate the temperature and magnetic field-dependent electrical and thermal properties of Eu2.2Ga11Sn35, revealing a change in electronic structure and an increase in magnetoresistance with increasing field, as well as the origin of magneto-suppressed thermal conductivity of this unconventional inorganic clathrate-I material with very low cation concentration. [ABSTRACT FROM AUTHOR]

We investigate the temperature and magnetic field-dependent electrical and thermal properties of Eu2.2Ga11Sn35, revealing a change in electronic structure and an increase in magnetoresistance with increasing field, as well as the origin of magneto-suppressed thermal conductivity of this unconventional inorganic clathrate-I material with very low cation concentration. [ABSTRACT FROM AUTHOR]

The spatial ecology of animals is influenced by the structure of their physical habitat, which affects the availability of refuges and microclimate, as well as the spatial positioning of resources. The use of space by the lizard Liolaemus tandiliensis was investigated in the Tandilia mountains of the Pampas region. We radio-tracked 19 adult lizards and found that home range size and distance moved were significantly affected by sex, with males having a home range 34% larger and moving longer distances than females. These parameters were also influenced by structural and thermal features of specific microhabitat types. The habitat structure inside the home range showed relatively high coverage of rocks and low coverage of vegetation. The thermal properties of the microhabitats were strongly associated with their occupancy; individuals used microhabitats of high thermal quality that exhibited environmental temperatures deviating the least from the preferred body temperature range of L. tandiliensis. Small-scale structural heterogeneity and thermal gradients were available in the Tandilia mountains, so L. tandiliensis individuals may not need to move large distances and may sustain themselves within a relatively small home range (mean=74.52 m2). Our findings suggest that L. tandiliensis occurs in a delicate balance with its specific habitat. This study provides information that must be taken into account for conservation planning, especially in light of the increasing anthropogenic degradation of the Tandilia mountains. [ABSTRACT FROM AUTHOR]

To study the service performance of polymer bilayer sheets, this experimental study focuses on the thermal and mechanical characterization of sheets composed of two polymer layers (named ABS/PMMA), an Acrylonitrile–Butadiene–Styrene layer and a 15% Poly(Methyl Methacrylate) layer. These sheets are used in many industrial components subjected to thermal and mechanical strain. The studied bilayer sheets were obtained by a co-extrusion process. Thermal properties were measured through Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Mechanical behavior was determined via uniaxial tensile tests at various temperatures less than the glass transition temperature and using two strain rates of 3.33 × 10−4 s−1 and 1.66 × 10−2 s−1. Furthermore, the viscoelastic properties are determined via Dynamic Mechanical Analysis (DMA) using two frequencies. The findings revealed substantial ABS/PMMA bilayer thermal stability. The obtained glass transition temperature of this bilayer was 111 °C. Its viscoelastic behavior was described by determining the storage and loss modulus. Furthermore, the influence of temperature and strain rate parameters on the tensile behavior of the ABS/PMMA bilayer was also determined showing high dependence of mechanical behavior on these two parameters. This bilayer exhibits brittleness at room temperature and high total strain exceeding 62% at 90 °C. [ABSTRACT FROM AUTHOR]

The chalkiness, starch fine structure, and physiochemical properties of rice starch were analyzed and their correlations were investigated under different nighttime temperatures during the early grain-filling stage. Compared to MT, medium temperature (MT) and low (LNT) and high (HNT) nighttime temperatures resulted in an increased chalky grain rate (CGR) and chalkiness degree (CD). LNT mainly affected the chalkiness by increasing peak1 (short branch chains of amylopectin), the branching degree, and the proportion of small starch granules but decreasing peak2 (long branch chains of amylopectin) and peak3 (amylose branches). This altered the pasting properties, such as by increasing the peak viscosity and final viscosity. However, HNT mainly affected the chalkiness by increasing peak2 and the crystallinity degree but decreasing peak1 and peak3. Regarding the thermal properties, HNT also elevated peak and conclusion temperatures. The CGR and CD were significantly and positively correlated with the proportions of small and medium starch granules, peak1, branching degree, gelatinization enthalpy, setback viscosity, and pasting time but markedly and negatively correlated with the proportion of large starch granules, amylose content, peak3, peak viscosity, and breakdown viscosity. These findings suggest that LNT and HNT disrupted the starch structure, resulting in increased chalkiness. However, their mechanisms of action differ. [ABSTRACT FROM AUTHOR]

Obtaining non-contact optical temperature sensing materials with good thermal stability and luminescent properties is one of the current research hotspots. In this work, Er3+/Yb3+ co doped CaGdAlO4:Erx,Yb0.10 (x = 0.006, 0.008, 0.010, 0.012, 0.014) single-phase phosphors were prepared by high-temperature solid-state method. For CaGdAlO4 : Erx, Yb0.10 powders with different Er3+ doping concentrations, the particle sizes range from 0.6 μm to 4.2 μm. When the samples are under 980 nm laser excitation, there exists two emission bands in the 500 * 575 nm range and one emission band in the 630 * 690 nm. The two stronger green emission bands located at 528 and 550 nm, and they could be attributed to ² H11/2→4 I15/2 and 4S3/2 →4 I15/2 transitions, while the weaker red emission band at 663 nm could be attributed to 4F9/2 →4 I15/2 transition of Er3+. The optimal upconversion luminescence intensity was obtained from CaGdAlO4 :Er0.010,Yb0.0. In the temperature range of 300 * 573 K, based on fluorescence intensity ratio FIR528/550 parameters, the absolute sensitivity SA increases from 44.4 x10-4 K-1 (@300 K) to 52.0 x 10-4 K-1 (@ 445 K), and then decreases to 49.0 x 10-4 K-1 (@ 573 K). The relative sensitivity SR decreases monotonically from 0.95 x 10-2 K-1 (@ 300 K) to 0.27 x 10-2 K-1 (@ 573 K). Furthermore, the heating-cooling cycling experiment shows that the thermal repeatability of temperature sensing for the phosphor is better than 98%. The results demonstrate that CaGdAlO4 :Er0. 010, Yb0.10 phosphors have potential applications in the field of optical temperature sensing. [ABSTRACT FROM AUTHOR]

Thermal safety issues of batteries have hindered their large‐scale applications. Nonflammable electrolytes improved safety but solvent evaporation above 100 °C limited thermal tolerance, lacking reliability. Herein, fire‐tolerant metal‐air batteries were realized by introducing solute‐in‐air electrolytes whose hygroscopic solutes could spontaneously reabsorb the evaporated water solvent. Using Zn/CaCl2‐in‐air/carbon batteries as a proof‐of‐concept, they failed upon burning at 631.8 °C but self‐recovered then by reabsorbing water from the air at room temperature. Different from conventional aqueous electrolytes whose irreversible thermal transformation is determined by the boiling points of solvents, solute‐in‐air electrolytes make this transformation determined by the much higher decomposition temperature of solutes. It was found that stronger intramolecular bonds instead of intermolecular (van der Waals) interactions were strongly correlated to ultra‐high tolerance temperatures of our solute‐in‐air electrolytes, inspiring a concept of non‐van der Waals electrolytes. Our study would improve the understanding of the thermal properties of electrolytes, guide the design of solute‐in‐air electrolytes, and enhance battery safety. [ABSTRACT FROM AUTHOR]

Sample holders for transmission electron microscopy (TEM) based on micro‐electro‐mechanical systems (MEMS) have recently become popular for investigating the behavior of nanomaterials under in situ or environmental conditions. The accuracy and reproducibility of these in situ holders are essential to ensure the reliability of experimental results. In addition, the uniformity of an applied temperature trigger across the MEMS chip is a crucial parameter. In this work, it is measured the temperature homogeneity of MEMS‐based heating sample supports by locally analyzing the dynamics of heat‐induced alloying of Au@Ag nanoparticles located in different regions of the support through quantitative fast high‐angle annular dark‐field scanning TEM tomography. These results demonstrate the superior temperature homogeneity of a microheater design based on a heating element shaped as a circular spiral with a width decreasing outwards compared to a double spiral‐shaped designed microheater. The proposed approach to measure the local temperature homogeneity based on the thermal properties of bimetallic nanoparticles will support the future development of MEMS‐based heating supports with improved thermal properties and in situ studies where high precision in the temperature at a certain position is required. [ABSTRACT FROM AUTHOR]

Gear transmission errors are influenced by temperature especially in the aerospace field. A model is proposed to investigate the influence of temperature on cylindrical gear transmission errors based on the thermal network (TETN). The gear temperature field distribution model is established based on the thermal network method, and gear thermal deformation can be calculated along the gear meshing line. Regarding the gear single-flank rolling process, the variation of gear transmission errors under temperature is determined. In numerical calculations in MATLAB, the variation of gear transmission errors at 100 ℃ compared to 20 ℃ is -4.20 μm, which decreases almost linearly while the thermal expansion coefficient of the gear material increases. The simulation of the gear transmission errors variation of temperatures using the finite element method (FEM) were carried out in Workbench software under Ansys and the average difference of the TETN model results between calculations and FEM for different temperatures was 0.24 μm. Experiments were carried out on the gear tester in temperatures ranging from 0℃ to 100℃, the TETN model results in calculations were compared with the results of the tester, and the average difference was -1.15 μm. The results show that the proposed TETN can be used as an algorithm to determine the variation of gear transmission errors under the influence of temperature. [ABSTRACT FROM AUTHOR]

Entropy plays a crucial role in designing new functional materials or enhancing material performance. The design of high entropy ceramics (HECs) introduces a larger composition space, thus the understanding of the correlation between the composition, entropy effect, and the performance of HECs is becoming increasingly important. In this work, to pursue superior properties, a series of CeNbO 4 -based solid solution ceramics with a maximum of 9 species cations in a single sublattice were synthesized by using high entropy configuration strategy. The interaction of composition, size disorder, and configurational entropy on the properties of HECs was emphasized. The potential conflict between high resistivity and low material constant of thermosensitive ceramics was overcome and thus achieving excellent thermal sensitivity properties having an extremely wide temperature range from room temperature to 1623 K and long-term high-temperature stability. This will bring innovative prospects for the design and application of high-temperature functional ceramics. [ABSTRACT FROM AUTHOR]

Since the fusing process in electrophotography has a significant impact not only on printing quality but also on machine internal temperature and toner blocking on outlet tray, accurate paper temperature prediction for various types of papers is essential, especially in the production printing. To develop the thermophysical model of fusing process to predict the paper temperature after the fusing process, thermal properties such as thermal conductivity, specific heat, and thermal contact resistance of several types of papers are necessary. However, paper is composed of complex fiber, surface coating, filler, and moisture, making it difficult to measure thermophysical properties of paper accurately. This work developed a machine learning (ML) model that can predict the thermophysical properties of paper based on a conventionally used 1D thermal network model of the fusing process and experiment results. The thermophysical properties of each paper obtained by ML and the thermophysical properties obtained by the conventional method were input to the thermal network model to predict the paper temperature after the fusing process and compared with the measured paper temperatures of the experiment. The results showed that the paper temperature was predicted with higher accuracy by using thermophysical properties obtained by ML than that by the conventional method. Although the method for predicting paper temperature by using only ML had been proposed, it had the disadvantage of requiring a large number of training experiments. In contrast, this method trained under the conditions of one fusing temperature and two printing speeds, and was able to predict under five fusing temperatures and four printing speeds. [ABSTRACT FROM AUTHOR]

The effect of thermal prehistory and mechanical field on the morphology and physicomechanical and thermal properties of poly(vinyl alcohol) cryogels has been studied. Using the methods of rheometry, DSC, and X-day diffraction analysis it is revealed that an increase in the heat treatment temperature of cryogels causes a rise of the melting temperature and a change in the crystallinity of PVA cryogels, as is typical for the annealing phenomenon. It is established that the annealing of PVA cryogels formed under repeated freezing with simultaneous forced compression contributes to the formation of cryogels with the spatial network being stable up to the onset of solvent boiling. [ABSTRACT FROM AUTHOR]

The influential effects of thermal treatment on material density, hardness, colour and microstructure of three commercially available woods in South Asia are evaluated. Wood specimens are isochronally annealed 120 min at different temperatures up to 250°C and isothermally annealed at 100°C, 150°C and 225°C up to 480 min under atmospheric pressure. Heat treatments cause density loss, hardness loss, darkening and microstructure frailer of woods, as the maximum temperature was increased. However, thermal treatment up to the temperature around 150°C shows lower values for the case of density, higher values for hardness and no remarkable changes in colour of wood specimens. Higher temperature treated samples are found to recover through absorbing water (moisture); however, chemically bonded water and thermally lost substances cannot be recovered. The diffuse reflectances of all the wooden samples decrease with the increase of annealing temperature, especially at colour band of higher wave length. The negative effects of the high-temperature thermal treatment on the properties of all the woods are observed due to removal of the free, loosely and chemically bonded water of woods, along with higher thermal degradation of cellulose, hemicelluloses and lignin. The SEM microstructures of the wood samples also comply with the present investigation showing the damage structure of fibres and pores. [ABSTRACT FROM AUTHOR]

The ground surface of green parks in arid and semi-arid areas may not be comfortable at specific times during the day and night due to the sun and the rate at which the subsoil gains or loses heat. Knowledge of the subsurface soil's thermal properties can provide designers with convenient and comfortable settings. Design focus is generally directed toward stability, density, and hydraulic conductivity. An assessment of the thermal properties of clay–sand mixtures of 10%, 20%, and 30% clay content is conducted. The proposed clay–sand layers are subjected to three different thermal gradients of 30, 20, and 10 degrees of magnitude. The profile of temperature changes was monitored using 5TE sensors and data loggers. The mixtures were also subjected to cooling at room temperature. The results indicate that the clay type and the clay content govern the response of subsurface clay–sand liners to temperature gain and loss. Two field sections with clay–sand layers of 15% and 20% clay were examined for temperature changes over an extended period. In winter, green areas rich in clays were found to keep heat for several hours and provide relatively warm evenings. In summer, the mixture retains a cool temperature for some time during the day. [ABSTRACT FROM AUTHOR]

Carbon-metal carbide composites are a novel family of materials with potential application in heat dissipation due to the lightness and thermal-mechanical properties. Within these composites, those of graphite-chromium carbide have been still few studied. Therefore, this research focuses on both the influence of the powder preparation method (mechanical mixing (MM) and colloidal synthesis (CS)) and the spark plasma sintering (SPS) temperature (1600, 1700, 1800, 1900 and 2000 °C) in the properties of the composite graphite-7 vol. Cr. Results indicate that the composites sintered from powders processed by CS exhibit better properties, which can be explained by the better dispersion of the chromium carbide, formed during the sintering process, in the matrix of composite. Apart from the powder preparation method, sintering temperature has influence on the properties of the composite: 1900 °C is the best in the case of the route CS + SPS, while 2000 °C is the best option in the route MM + SPS. The thermal conductivity in-plane is 1.75 times greater in the CS than in the MM route, which suggests a better performance in the composite processed by colloidal route in heat dissipation applications. [ABSTRACT FROM AUTHOR]

The effect of moisture absorption and temperature on the thermal properties of dried tigernut was studied. The proximate composition includes moisture content ranging from 0.97% to 6.45%, Ash content from 0.63% to 1.93%, fat from 12.95% to 16.63%, crude fiber from 18.71% to 33.78%, and carbohydrate from 43.58% to 58. 68%. The thermal properties were determined by using the value obtained from the proximate composition and calculated using the Okoi and choi's equation. The value obtained from the thermal properties are thermal conductivity which ranged from 0.28866 w/moc to 0.3562 w/moc, thermal diffusivity ranging from 0.1123m2/s to 0.2172ms/s and specific heat capacity ranging 1.8484 kg/kgoc to 1.9261 kg/kgoc. The percentage moisture absorption capacity was also analyzed in the sample which ranged from 46.6% to 94.4%. Thermal properties refer to the response in their temperature. The result obtained showed that the sample conditioned at 100°C had the highest thermal properties and this implied that the thermal properties of food is generally influenced by moisture, temperature and their proximate composition. Further studies should be carried out on the Rheological properties of tigernut, kinetic rate of reaction of the nutrient with respect to time and the thermal properties should be utilized for the design of equipment and for the mathematical model in terms of simulation and mass heat transfer in the material. [ABSTRACT FROM AUTHOR]