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This study presents the preliminary outcomes of a methodology for the physical and mechanical characterization of various chestnut elements in different states of preservation. Strategizing conservation and retrofit interventions for timber is necessary, and to do this, it is necessary to establish an estimation of physical (transmissivity, thermal conductivity, humidity level, etc.) and mechanical properties (density, compressive or bending strength, etc.). This essential information is typically associated with timber defects, but there are lack of correlations. The primary objective is to establish correlations between thermal and density properties with the aim of preserving original assets. The investigation delves into the relationship between timber density and thermal properties through experimental non-destructive testing (NDT). Two NDTs were employed with the aim of correlating: penetrometric testing and active thermography investigations. The parametric study on the excitation period yielded valuable insights into the temporal dynamics of heat transfer within the timber, underscoring the significance of selecting appropriate excitation periods to capture precise thermal properties. Tabular data on relative humidity for salified, dried, and new samples provided a quantitative backdrop to these observations, unveiling the nuanced effects of humidity on the timber's thermal response. The results of this study are positioned to inform future conservation efforts by laying the groundwork for a comprehensive understanding of timber's mechanical properties. Particularly, the challenge lies in accurately estimating density, where surface tests are often less reliable than in-depth ones. Therefore, it is crucial to seek validation through other NDT tests, such as thermographic analysis and visual inspection, and hygrometric tests recognizing their importance in enhancing the reliability of density assessments. This approach will contribute to the development of more discerning preservation strategies. [ABSTRACT FROM AUTHOR]

Glass is considered a sustainable material with achievable recovery rates within the EU. However, there are limited data available for construction glass waste management. Furthermore, glass is a heavy material, and considering the geographical limitations of Cyprus, the transportation trading cost within the EU is extremely high. Therefore, another method for utilizing this by-product should be developed. The aim of this research is to investigate the production of a low-cost, lightweight and fireproof material able to retain its structural integrity, using the geopolymerization method with the incorporation of randomly collected construction glass waste. The glass waste was initially processed in a Los Angeles abrasion machine and then through a Micro-Deval apparatus in order to be converted to a fine powder. Mechanical (compressive and flexural strength), physical (setting time and water absorption) and thermal properties (thermal conductivity) were investigated. The fire-resistant materials presented densities averaging 450 kg/m3 with a range of compressive strengths of 0.5 to 3 MPa. Additionally, a techno-economic analysis was conducted to evaluate the viability of the adopted material. Based on the results, the final geopolymer product has the potential to be utilized as a fire resistance material, preventing yielding or spalling. [ABSTRACT FROM AUTHOR]

This work investigates the physical–thermal properties of nanofluids made from graphene powder, propylene glycol, and water. Propylene glycol and water were mixed in the following ratios to make nanofluids: 100:0, 75:25, and 50:50. Graphene was added at 0.25 and 0.5% of the mixture's volume to the three base fluids. Nanofluids' viscosity, density, thermal conductivity, and specific heat are studied. After mixing with graphene nanopowder, critical fluids increased in density and thermal conductivity. Essential fluids showed these advantages. When the temperature was elevated, viscosity and specific heat decreased. Despite constant temperatures, this was the case. Increasing graphene concentration increases thermal conductivity by 10–16%. The viscosity of nanofluids with graphene nanopowder is less affected by temperature. As temperature rises, nanofluid density falls. Temperature and density are inversely related; thus, this makes sense. Adding graphene to propylene glycol at different concentrations increased its specific heat by 8–14%, depending on the concentration. [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 densities of molten Y2O3‐Al2O3 compounds, including yttrium aluminum garnet (Y3Al5O12), were determined over a wide temperature range that included an undercooled region, using an electrostatic levitation furnace. The density of the molten Y3Al5O12 varied with temperature according to the relationship 3750 − 0.25(T − Tm) (kg/m3) with Tm = 2240 K and for the range of 1300 K ≤ T ≤ Tm, yielding the thermal expansion coefficient ɑ = 6.7×10−5 K−1. The molar volumes of molten (100‐x)Y2O3‐xAl2O3 (x = 0, 33.3, 50, 55, 62.5, 76.5, 81.5, or 100 mol%) were found to vary with the value of x in a linear manner within the superheated temperature range. However, the molar volumes in the undercooled region deviated from those calculated using an ideal solution model owing to attractive interactions between Y2O3 and Al2O3. [ABSTRACT FROM AUTHOR]

The roasting process of Gari (Gelatinized cassava mash), a shelf-stable cassava product, is energy-intensive. Due to a lack of information on thermal characteristics and scarcity/rising energy costs, heat and mass transfer calculations are essential to optimizing the traditional gari procedure. The objective of this study was to determine the proximate, density, and thermal properties of traditionally processed de-watered cassava mash and gari at initial and final processing temperatures and moisture contents (MCwb). The density and thermal properties were determined using proximate composition-based predictive empirical models. The cassava mash had thermal conductivity, density, specific heat capacity, and diffusivity of 0.34 to 0.35 W m−1 °C−1, 1207.72 to 1223.09 kg m−3, 2849.95 to 2883.17 J kg−1 °C, and 9.62 × 10−8 to 9.76 × 10−8 m2 s−1, respectively, at fermentation temperatures and MCwb of 34.82 to 35.89 °C and 47.81 to 49%, respectively. The thermal conductivity, density, specific heat capacity and diffusivity of gari, ranged from 0.27 to 0.31 W m−1 °C−1, 1490.07 to 1511.11 kg m−3, 1827.71 to 1882.61 J kg−1 °C and 9.64 × 10−8 to 1.15 × 10−8 m2 s−1, respectively. Correlation of all the parameters was achieved, and the regression models developed showed good correlation to the published models developed based on measuring techniques. [ABSTRACT FROM AUTHOR]

The aim of this work is to investigate the possibility of recycling Walnut Shell wastes (WS) as fine aggregates in lightweight self-compacting mortar (SCM). In the experimental procedure, the natural sand was partially replaced by the WS waste at various replacement ratios (0; 10; 20; 30 and 40%). The thermal conductivity and some physic-mechanical properties of the SCM containing WS were studied and compared with control SCM (CSCM). The test results showed that, depending on the amount of WS aggregate, unit weight and thermal conductivity of concrete were reduced and the capillary water absorption was increased with the use of WS aggregates and for all the lightweight SCMs considered. Moreover, reductions in mechanical properties of concretes have been obtained with decreasing concrete unit weights. In addition, substitution ratio of 30% was found to be the optimum volume ratio of WS for getting lightweight structural SCM with appropriate fresh and hardened properties. [ABSTRACT FROM AUTHOR]

Plastic packaging products are popular due to having many superior properties but are harmful to the environment. In that regard, potato starch and sugarcane bagasse fibers were used to develop a composite material by hand layup process. Starch was chemically modified chemically using sodium hydroxide, adipic acid, and mustard oil, according to a previous study. The modification process improved the gelatinization of starch and helped to form a dense and rigid film. The combination was used along with sugarcane bagasse to develop a novel composite material. An increase in fiber loading in the composite resulted in 14.00 J/m impact resistance and 22.85 MPa flexural strength. But adding more than 43% fiber caused decrement in the properties due to fiber accumulation. In contrast, the hardness test showed almost similar results for all samples, resembling polystyrene's hardness properties. However, the density of the composites was found around 0.61 gm/cm3, which is significantly low while the scanning electron microscopy images showed the presence of mechanical interlocking among the components and the composites' porous structure, which also helped to reduce the composites' density significantly. In addition, a meaningfully improved absorbency property was recorded as 73% water absorption after 2 h of immersion was seen in one sample. The thermal test showed similar results to raw sugarcane bagasse but with high char-forming ability in the composite, which can be helpful in flame retarding properties. Meanwhile, comparison with polystyrene and cardboard in terms of density and impact resistance also showed encouraging results.

Finely dispersed (CeO2)1−x(Sm2O3)x (x = 0.05, 0.10, 0.20) and (CeO2)1−x(Nd2O3)x (x = 0.05, 0.10, 0.15, 0.20, 0.25) powders were synthesized via liquid-phase techniques based on the co-precipitation of hydroxides and were used to obtain ceramic materials comprising fluorite-like solid solutions with CSR in the range 69–88 nm (upon annealing at 1300 °C) and open porosity in the range 0.6–6.2%. The physicochemical properties of the synthesized materials were comparatively characterized. In general, the prepared materials were found to possess a mixed type of electrical conductivity, but in the medium-temperature range, the ionic component was predominant (ion transfer numbers ti = 0.93–0.73 at 300–700 °C). The highest ionic conductivity was observed for CeO2-based samples containing 20 mol.% Sm2O3 (σ700°C = 3.3 × 10−2 S/cm) and 15 mol.% Nd2O3 (σ700°C = 0.48 × 10−2 S/cm) was in the temperature range 500–700 °C. The physicochemical properties (density, open porosity, type and mechanism of electrical conductivity) of the obtained ceramic materials make them promising as solid oxide electrolytes for medium temperature fuel cells. [ABSTRACT FROM AUTHOR]

Finely dispersed (CeO2)1−x(Nd2O3)x (x = 0.05, 0.10, 0.15, 0.20, 0.25) powders are synthesized via liquid-phase techniques based on the co-precipitation of hydroxides and co-crystallization of nitrates. The prepared powders are used to obtain ceramic materials comprising fluorite-like solid solutions with the coherent scattering region (CSR) of about 88 nm (upon annealing at 1300 °C) and open porosity in the range of 1–15%. The effect of the synthesis procedure and sintering additives (SiO2, ZnO) on physicochemical and electrophysical properties of the resulting ceramics is studied. The prepared materials are found to possess a predominantly ionic type of electric conductivity with ion transfer numbers ti = 0.96–0.71 in the temperature range of 300–700 °C. The conductivity in solid solutions follows a vacancy mechanism with σ700 °C = 0.48 × 10−2 S/cm. Physicochemical properties (density, open porosity, type and mechanism of electrical conductivity) of the obtained ceramic materials make them promising as solid oxide electrolytes for medium temperature fuel cells. [ABSTRACT FROM AUTHOR]

Amorphous alumina (a-AlOx), which plays important roles in several technological fields, shows a wide variation of density and composition. However, their influences on the properties of a-AlOx have rarely been investigated from a theoretical perspective. In this study, high-dimensional neural network potentials were constructed to generate a series of atomic structures of a-AlOx with different densities (2.6 g/cm3–3.3 g/cm3) and O/Al ratios (1.0–1.75). The structural, vibrational, mechanical, and thermal properties of the a-AlOx models were investigated, as well as the Li and Cu diffusion behavior in the models. The results showed that density and composition had different degrees of effects on the different properties. The structural and vibrational properties were strongly affected by composition, whereas the mechanical properties were mainly determined by density. The thermal conductivity was affected by both the density and composition of a-AlOx. However, the effects on the Li and Cu diffusion behavior were relatively unclear. [ABSTRACT FROM AUTHOR]

Glass is considered a sustainable material with achievable recovery rates within the EU. However, there are limited data available for construction glass waste management. Furthermore, glass is a heavy material, and considering the geographical limitations of Cyprus, the transportation trading cost within the EU is extremely high. Therefore, another method for utilizing this by-product should be developed. The aim of this research is to investigate the production of a low-cost, lightweight and fireproof material able to retain its structural integrity, using the geopolymerization method with the incorporation of randomly collected construction glass waste. The glass waste was initially processed in a Los Angeles abrasion machine and then through a Micro-Deval apparatus in order to be converted to a fine powder. Mechanical (compressive and flexural strength), physical (setting time and water absorption) and thermal properties (thermal conductivity) were investigated. The fire-resistant materials presented densities averaging 450 kg/m3 with a range of compressive strengths of 0.5 to 3 MPa. Additionally, a techno-economic analysis was conducted to evaluate the viability of the adopted material. Based on the results, the final geopolymer product has the potential to be utilized as a fire resistance material, preventing yielding or spalling.

This study aims to evaluate the thermal and mechanical performances of PET-G thermoplastics with different 3D microstructure patterns and infill densities. The production costs were also estimated to identify the most cost-effective solution. A total of 12 infill patterns were analysed, including Gyroid, Grid, Hilbert curve, Line, Rectilinear, Stars, Triangles, 3D Honeycomb, Honeycomb, Concentric, Cubic, and Octagram spiral with a fixed infill density of 25%. Different infill densities ranging from 5% to 20% were also tested to determine the best geometries. Thermal tests were conducted in a hotbox test chamber and mechanical properties were evaluated using a series of three-point bending tests. The study used printing parameters to meet the construction sector's specific needs, including a larger nozzle diameter and printing speed. The internal microstructures led to variations of up to 70% in thermal performance and up to 300% in mechanical performance. For each geometry, the mechanical and thermal performance was highly correlated with the infill pattern, where higher infill improved thermal and mechanical performances. The economic performance showed that, in most cases, except for the Honeycomb and 3D Honeycomb, there were no significant cost differences between infill geometries. These findings can provide valuable insights for selecting the optimal 3D printing parameters in the construction industry. [ABSTRACT FROM AUTHOR]

Engineering properties of wild banana seeds at different moisture content (8.66%, 12%, 16%, 20%, and 24% db) were investigated. Physical dimensions, seed surface area (SA), seed volume (SV), and thousand seed mass (M1000) increased linearly with increase inmoisture content. While porosity decreased linearly from 42.33% to 38.89%, bulk density (ρb) and true density (ρt) increased from 513.59 to 564.72 and 890.56–924.09 kg m−3, respectively. The angle of repose increased linearly from 29.84 to 36.48 with moisture content. The increased moisture content also caused an increase in static coefficient of friction for surfaces made of stainless steel, glass, and plywood. The thermal conductivity (λ) and volumetric specific heat (ρcp) were found to increase linearly from.17 to.20 Wm−1 K−1, and.58 to.99 MJ m−3 K−1, and thermal diffusivity (α) decreased from.31 to.19 (×10−6 m2 s−1) with a increase in moisture content. Practical applications: The research aimed to study the engineering properties of wild banana seeds as a function of moisture content as they are necessary to design equipment for handling, aeration, storage, and processing. Moreover, it helps in predicting flow and handling behavior during processing, including hopper flow, and conveying through feeders and other handling equipment. Furthermore, thermal properties are helpful in engineering, process design and modeling the thermal behavior of food products during storage, processing, and transportation. [ABSTRACT FROM AUTHOR]

This research aims to study the physical and thermal properties of concrete blocks mixed with Bakelite. The main goal of this research is to use Bakelite plastic to replace the total mass of concrete blocks. The laboratory tests include compressive strength test, density test, water absorption test, and thermal conductivity test. The concrete blocks are mixture of Portland cement type one, dust stone, sand, and Bakelite plastic. The mixing ratio of concrete blocks with a binder to total mass is 1:5 by weight. The percentage of Bakelite plastic varies from 0% to 20% and the curing method of concrete blocks is air curing for 7, 14, and 28 days. The compressive strength and density tests were conducted after the completion of each curing period, while the water absorption test was conducted only for the curing period of 28 days. Two groups of concrete block samples, 50x50x50 mm³ were used in the physical properties tests, while 100x100x100 mm³ concrete block samples with the curing period of 28 days were used in the thermal conductivity test. The result shows that an increasing in the percentage of Bakelite decreases the compressive strength and density of concrete block samples. The water absorption is in proportion to the increasing of percentage of Bakelite. Finally, an increasing of Bakelite ranging from 0% to 20% roughly reduces the thermal conductivity of concrete block samples from 0.5 W/m-K to 0.3 W/m-K. [ABSTRACT FROM AUTHOR]

The article discusses the influence of briquetting/compaction parameters. This includes the effects of pressure and temperature on material density and the thermal conductivity of biomass compacted into briquette samples. Plant biomass mainly consists of lignin and cellulose which breaks down into simple polymers at the elevated temperature of 200 °C. Hence, the compaction pressure, compaction temperature, density, and thermal conductivity of the tested material play crucial roles in the briquetting and the torrefaction process to transform it into charcoal with a high carbon content. The tests were realized for samples of raw biomass compacted under pressure in the range from 100 to 1000 bar and at two temperatures of 20 and 200 °C. The pressure of 200 bar was concluded as the most economically viable in briquetting technology in the tests conducted. The conducted research shows a relatively good log relationship between the density of the compacted briquette and the compaction pressure. Additionally, higher compaction pressure resulted in higher destructive force of the compacted material, which may affect the lower abrasion of the material. Regarding heat transfer throughout the sample, the average thermal conductivity for the compacted biomass was determined at a value of 0.048 ± 0.001 W/(K∙m). Finally, the described methodology for thermal conductivity determination has been found to be a reliable tool, therefore it can be proposed for other applications. [ABSTRACT FROM AUTHOR]

Ionanofluids (INF) are combinations of ionic liquid (IL) and nanoparticles (NP) with superior thermophysical properties. In the present study, measurement of thermophysical profile of IL, 1-ethyl-3-methylimidazolium chloride ([EMiM]Cl) in which Al2O3 NPs are dispersed were undertaken in the temperature range of 303.15–333.15 K. INFs were prepared by dispersing Al2O3 NPs in different mass concentrations of 0.5, 1.0, 2.5, 5.0, and 10%. The results showed that specific heat and thermal conductivity increase with both concentration and temperature. In contrast, the viscosity and density increase with concentration and decrease with temperature rise. The maximum INF thermal conductivity and viscosity enhancements were 21.9% and 77.6% for a mass concentration of 10% compared to IL at 333.15 K and 303.15 K. Electrical conductivity decreases with NP addition and increases linearly with an increment in temperature. Based on the measured results, a correlation for the specific heat, thermal conductivity, and viscosity of INF was proposed. Further, the heat transfer performance of studied INF is theoretically estimated based on the experimental thermophysical properties. Finally, for high-temperature applications methylimidazolium chloride-based INFs can be used as an efficient candidate as primary heat transfer fluid. [ABSTRACT FROM AUTHOR]

Shape-memory polymers (SMPs) show great potential in various emerging applications, such as artificial muscles, soft actuators, and biomedical devices, owing to their unique shape recovery-induced contraction force. However, the factors influencing this force remain unclear. Herein, we designed a simple polymer blending system using a series of tetra-branched poly(ε-caprolactone)-based SMPs with long and short branch-chain lengths that demonstrate decreased crystallinity and increased crosslinking density gradients. The resultant polymer blends possessed mechanical properties manipulable across a wide range in accordance with the crystallinity gradient, such as stretchability (50.5–1419.5%) and toughness (0.62–130.4 MJ m−3), while maintaining excellent shape-memory properties. The experimental results show that crosslinking density affected the shape recovery force, which correlates to the SMPs' energy storage capacity. Such a polymer blending system could provide new insights on how crystallinity and crosslinking density affect macroscopic thermal and mechanical properties as well as the shape recovery force of SMP networks, improving design capability for future applications. [ABSTRACT FROM AUTHOR]

Background: The uptake of topical formulations can be enhanced through laser pretreatments. Newer technologies, such as non‐ablative fractional lasers (NAFLs), can target dermal tissues and spare the stratum corneum (SC), which can mitigate common side effects associated with ablative laser treatment. Objective: To discuss the parameters of 2 NAFL pretreatment systems (1440‐nm/1927‐nm diode system or 1550‐nm erbium‐doped glass/1927‐nm thulium system), which can be paired with topicals to improve their cutaneous uptake. Methods and Materials: The parameters of the 1440‐nm/1927‐nm diode system and 1550‐nm erbium‐doped glass/1927‐nm thulium system were reviewed, as well as in vivo experiments using both laser systems. Results: Multiple parameters should be optimized to enhance the uptake of various topical formulations and minimize side effects, including wavelength, spot size, density, pulse duration, thermal properties, and topical formulation. Chosen therapeutic parameters must account for patient‐specific factors, such as treatment indication, therapeutic area, and Fitzpatrick skin type. In vivo experiments have demonstrated that both laser systems are effective in enhancing the uptake of various topical therapies relative to untreated controls. Conclusion: Individualization of laser system parameters increases efficiency and minimizes risk. [ABSTRACT FROM AUTHOR]

Volumetric characteristics of high-entropy alloys (HEAs) are among the main ones when considering possible practical applications of these materials. Low specific gravity is an important parameter providing the use of these alloys in industry. Density of AlNiCoCuZr HEAs with different component ratios has been experimentally investigated in the present work in a wide temperature range, including liquid state. Molar volume in liquid state and temperature coefficients of expansion in full temperature range (from room temperature up to 1800 K) were calculated basing on the experimental data. Structure of the alloys and thermal reactions during heating and cooling were studied. Two BCC - solid solutions, as well as solution based on (half)-Heusler phase ZrNi 2 Al were found. The presented results can provide a basis for further experimental study of AlNiCoCuZr HEAs and numerical modeling of their properties. • Al–Ni–Co–Cu–Zr high-entropy alloys were synthesized. • Structure and phase composition of AlNiCoCuZr HEAs were determined. • Density of AlNiCoCuZr HEAs in solid and liquid states was studied experimentally. [ABSTRACT FROM AUTHOR]

New glasses based on Sb2O3–PbO association have been synthesized and characterized. The limits for glass formation have been investigated in ternary systems encompassing trivalent oxides such as Al2O3, Ga2O3, and In2O3 as the third component. Fast quenching is required to prevent melt crystallization, which results in thin samples. Chemical analysis shows a rather good agreement between nominal and analyzed compositions. Glass transition temperature, Tg, ranges between 255°C and 280°C, depending on composition. Density and hardness have been measured for typical samples. [ABSTRACT FROM AUTHOR]

Aleppo pine (Pinus halepensis Mill.) is the main forest species of Algeria occupying more than 35% of the total forest area of the country. However, the physicomechanical and thermal characteristics of Algerian P. halepensis wood are not well-known. This research investigates the physical (moisture, density, swelling, and shrinkage), mechanical (bending strength and modulus of elasticity), and thermal (mass loss under combustion and pyrolysis as well as thermal conductivity) properties of P. halepensis wood from the Darguina (Bejaia) forest in Algeria. The results showed that Algerian P. halepensis wood with a mean density of 540 kg m-3 has good dimensional stability in swelling and shrinkage, with 116.43 MPa bending strength and a modulus of elasticity of 17,520 MPa. The wood shows a good thermal resistance under low-temperature range and has a thermal conductivity of 0.21 W m-1 K-1. The overall results indicate that Algerian P. halepensis wood may be commercially exploited for construction and insulation applications, namely in the production of sandwich composites. [ABSTRACT FROM AUTHOR]

New glasses based on Sb2O3–PbO association have been synthesized and characterized. The limits for glass formation have been investigated in ternary systems encompassing trivalent oxides such as Al2O3, Ga2O3, and In2O3 as the third component. Fast quenching is required to prevent melt crystallization, which results in thin samples. Chemical analysis shows a rather good agreement between nominal and analyzed compositions. Glass transition temperature, Tg, ranges between 255°C and 280°C, depending on composition. Density and hardness have been measured for typical samples. [ABSTRACT FROM AUTHOR]

The NWA 869 chondrite is among many common stony regolith breccia meteorites that have been collected from northwest Africa (NWA). It is composed of Fe sulphide and Fe-Ni metallic phase inclusions embedded in a silicate stony matrix (primarily pyroxene). Although the physical properties of meteorites are the implementation of their mineral and chemical compositions, their electric and dielectric properties (electric conductivity σ , dielectric constant ε′ , and dielectric loss ε") are rarely studied, while no literature has been published on their thermal properties (thermal conductivity K, thermal diffusivity α, specific heat capacitance Cp, and thermal effusivity e). Consequently, the present study deals with studying the electric and dielectric properties of the NWA 869 chondrite at a frequency range (4.0 Hz-8.0 MHz), and their behavior against the applied frequency (fingerprint) was matched. Also, the thermal properties were measured at the ambient conditions. The porosity and density of the chondrite were also measured using helium injection technique. To explain the electric and thermal properties of the meteorite sample, its internal structure as well as its mineral and chemical compositions were revealed using the environmental Scanning electron microscopy (ESEM) supported by the EDAX technique. It is indicated that the chondrite is composed of iron sulphide and Fe-Ni inclusions scattered in a stony silicate matrix; it is characterized by moderate density (3.5069 g/cc) with a considerable porosity value (2.12 %). It is also characterized by moderate electric conductivity (σ), dielectric constant (ε′), and dielectric loss (ε") values (0.50 < σ < 2037.3 ohmm, 67.0 < ε' < 1713.7, and 0.22 < ε" < 12,432 at frequency range 4 Hz-8MHz, respectively). Also, it is characterized by thermal conductivity (K), thermal diffusivity (α), thermal capacitance (Cp), and thermal effusivity (e) values of average 1.5185 W/(K.m), 1.5425 mm2/s, 286 J/(K.kg), and 2628 W(s)0.5/m2K, respectively. • The NWA-869 chondrite is a regolith breccia L3-6 meteorite; it is sulfide inclusions in silicate matrix. • It has moderate electric conductivity (σ), dielectric constant (ε′), and dielectric loss (ε"). • It has moderate thermal conductivity (k), effusivity (e), diffusivity (α), and specific heat capacitance (Cp). • Electric conductivity increases by increasing the AC frequency and decreasing the dielectric constant. • Thermal conductivity increases by increasing the thermal effusivity and the specific heat capacitance. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the thermal behavior of composite building materials comprised of silt and flax fibers, considering various initial conditions. The experiments were conducted on flax fibers alone, examining factors such as moisture content variation, fibers arrangement, and density. Subsequently, the thermal properties of the earth-flax fiber composite were studied, taking into account the influence of water content and fibers mass content. The thermal properties of both flax fibers and raw earth-flax fibers composite specimens were determined using the experimental unsteady-state method. The results indicate that the thermal conductivity and heat capacity of flax fibers increase with density, temperature, and moisture content. Regardless of fibers density and arrangement of fibers, linear relationships have been established for both thermal conductivity and heat capacity as functions of temperature. Additionally, it was demonstrated that the heat capacity and the thermal conductivity increase with water content, regardless of the percentage of added fibers. Moreover, mixing randomly flax fibers with compacted raw earth material has improved the thermal properties of the composite. This improvement pertains to its insulating capacity, ability to store heat, and, subsequently, its contribution to the thermal comfort provided by such earth composite material when used as a building material. • Thermal conductivity enhances by increasing the moisture content and density. • The arrangements of fibers have highly influenced the thermal properties. • Linear relationships were established for the thermal conductivity and heat capacity. • The addition of flax fibers to raw earth improved the thermal properties. [ABSTRACT FROM AUTHOR]

Summary: Currently, there is an expanded utilisation of lightweight construction structures in buildings, which results in a low structure's thermal storage capacity of the envelope due to the application of thermally unsuitable materials. PCMs incorporated into building structures components are potential alternatives to manage the inadequate thermal energy storage capacity of lightweight structures. To provide a guide for selecting and applying commercial PCMs in construction, nine organic and inorganic bulk materials were selected, and their thermophysical properties were characterised. Thus, the enthalpy of melting/crystallisation, the melting/crystallisation temperature, the stability of 50 cycles, and the verification of the presence of the subcooling phenomenon by DSC and the T‐history method were evaluated. Since the adequate methods to incorporate the PCMs in gypsum are suspension and vacuum impregnation, their thermal properties, together with density and viscosity, need to be considered, properties that are not typically reported in the datasheets of commercial PCMs. Furthermore, the temperature dependence of the viscosity and density of the solid/liquid PCMs were measured by a rheometer and densimeter/pycnometer, respectively. Based on liquid and solid density values, the volumetric expansion of PCMs during the melting process was calculated. Finally, the characterisation parameters were compared with those provided by the suppliers of the different companies. The characterisation's results indicate that for both organic and inorganic PCMs, the fusion temperature (21°C‐26°C) and the density values (0.777‐1.515 g/cm3 for liquid state and 0.895‐1.860 g/cm3 for solid state) were consistent with the values provided in the datasheet from the suppliers'. Viscosity values were found to be higher than expected, and the enthalpy was found to be lower (19%‐30%) when compared with the technical datasheets from manufacturers'. The cycling stability study results were consistent only for the organic samples, without displaying phase segregation or subcooling problems. Based on the thermophysical characterisation, it was possible to establish that three organic RT‐21, RT‐21(TA), RT‐25, and three inorganic SP‐21E, PCM 21C, HS‐24P PCMs would be suitable products for their inclusion into gypsum boards under the conditions analysed. These findings provide new insights regarding the applicability and development of new strategies and materials for passive or active heating/cooling applications in buildings. [ABSTRACT FROM AUTHOR]

Foamed plastics are increasingly employed due to the high demand in functional materials with reduced weight. Bead foams in general offer low weight and excellent thermal insulation properties combined with extremely high freedom in design. Though foams show increased risk of ignition and heightened heat release, literature on burning behavior is rather limited. Therefore, this study investigates density‐dependent burning behavior of commercial bead foams like expanded polypropylene (EPP) and expanded modified polyphenyleneether (E‐mPPE) by cone calorimetry. The results are compared to existing studies on the density‐dependent burning behavior of different foams, mainly expanded polystyrene and foamed polyurethane. The importance of density as a characteristic is highlighted by the linear dependence of total heat emission on density for all investigated polymers, making a prediction of thermal loads possible. The peak heat release rate of flame‐retarded EPP and E‐mPPE was found not to be dependent on density, indicating an increased homogeneity by addition of flame retardant. [ABSTRACT FROM AUTHOR]

Flexible thermal conducting materials with the combination of excellent thermal conductivity and mechanical strength are highly desired for many practical applications, but meeting this strict requirement remains as a big challenge. Herein, facile preparation of highly aligned carbon nanotube (CNT) films is demonstrated, which involves the continuous production of a hollow cylindrical CNT assembly, followed by in-situ alignment of CNTs through optimizing the winding rate and a further stretching-pressing process. Benefiting from the resultant excellent CNT alignment and high density (1.59 ± 0.05 g cm−3), the CNT film simultaneously has a high thermal conductivity of 558.06–700.15 W m−1 K−1, electrical conductivity of 4870 ± 150 S cm−1, mechanical strength of 2.74–2.95 GPa, and Young's modulus of 55.2–58.9 GPa. The combination of such high thermal and mechanical properties is outstanding for carbon-based thermal conducting materials. Furthermore, the CNT material exhibits negligible structural and mechanical decay even after 500 cycles of bending test. Our study provides an effective strategy toward developing new thermal conducting materials for applications under harsh conditions. [Display omitted] • Carbon nanotube (CNT) films with excellent CNT alignment and ultra-high density (1.59 g cm−3) are prepared. • The CNT film simultaneously has a high thermal conductivity (558.06–700.15 W m−1 K−1) and strength (2.74-2.95 GPa). • The high thermal conductivity of the CNT film is attributed to the excellent CNT alignment and ultra-high density. [ABSTRACT FROM AUTHOR]

The devitrification, "cold" crystallization, and glass transition temperatures and melting point of samples in the B2O3–CaO–Al2O3–PbO system have been determined by differential thermal analysis. The viscosity of aluminum calcium borate melts containing up to 6.9% PbO has been measured in the temperature range 1153–1573 K. The results demonstrate that lead oxide additions reduce melt viscosity and that the density and surface tension of the melts increase with increasing lead oxide content and decrease with increasing temperature. High- and low-temperature regions have been identified where the melts have properties of Newtonian fluids. Cooling leads to polymerization and vitrification of the melts. [ABSTRACT FROM AUTHOR]

We have investigated 78 core samples of basaltic trap and Neoarchean basement in the laboratory from a 981 m deep scientific borehole KBH‐05, in the Koyna−Warna seismic zone, in order to characterize their thermal and physical properties and present a probable crustal thermal model. The Koyna−Warna, located in the Deccan Volcanic Province (DVP), is globally one of the most prominent Reservoir Triggered Seismicity (RTS) regions. Thermal conductivity, density, and porosity vary widely (1.0–1.7 Wm−1K−1, 2,400–3,000 kg m−3, 0.2%–10%) for the basalt due to their lithological heterogeneities, i.e., massive/amygdaloidal/vesicular. In comparison, the basement, which dominantly consists of gneiss/migmatite gneiss (granodiorite to tonalite to quartz monzodiorite in composition) and amphibolite, have shown a wider range in thermal conductivity (2.2–3.4 Wm−1K−1) but constricted range in density and porosity (2,600–2,800 kg m−3, 0.01%–0.15%). Based on gamma and sonic logs, as well as radioelements (Th, U, K), the 499 m thick basaltic trap can be divided into two thick layers (325, 174 m) and five sub‐layers, which can be correlated with different basaltic formations. Similarly, the underlying basement can also be divided into two layers (93, 384 m). The upper basement layer has two times higher concentrations of Th and U than the lower layer, with heat production of 2.0, 0.8 μWm−3. Further, the study provides a robust temperature estimate of 165°C–250°C at 10 km depth, considerably higher than reported earlier for the DVP, and reveals that in addition to thermal parameters, RTS also plays an important role in the seismogenesis of the region. Plain Language Summary: The Koyna‐Warna region, located in the western part of Deccan Volcanic Province, India, is one of the finest examples of Reservoir Triggered Seismicity in the world. Scientific deep drilling provides a rare opportunity to study thermal and physical properties of a one‐km thick drilled column consisting of a half‐km basaltic trap and another half‐km concealed basement. Study also provides a robust upper crustal thermal model for this region and provides an insight into the causes of seismogenesis. Before laboratory measurements, studied core samples have been characterized by petrology, geochemistry, and geophysical logs. Significant variations in thermal conductivity and density in the basaltic trap could be attributed to the lithological heterogeneities from massive to amygdaloidal/vesicular basalts, while the basement to the compositional variations from granodiorites to tonalites to quartz monzodiorites. Based on gamma and sonic logs, as well as radioelements, the basaltic trap can be divided into two layers and five sub‐layers, which can be correlated to basalt flows. Similarly, the underlying basement can be divided into two layers, with two times higher radioelements in the upper‐layer. Further, the study reveals that in addition to thermal parameters, Reservoir Triggered Seismicity also plays an important role in the seismogenesis of the region. Key Points: Basalt trap & basement beneath Koyna‐Warna show variations in thermal/physical properties that have been correlated to lithology/compositionBased on gamma and sonic logs as well as radioelements, the basalt trap can be divided into five sub‐layers which can be correlated with basalt flowsRobust temperature estimate at 10‐km depth revealed that seismicity is not entirely controlled by temperature, but also by reservoir‐induced [ABSTRACT FROM AUTHOR]

Anisotropic cellulose nanocrystal (CNC) foams with densities between 25 and 130 kg m−3 (CNC25 –CNC130) were prepared by directional ice-templating of aqueous dispersions. Estimates of the solid and gas conduction contributions to the thermal conductivity of the foams using a parallel resistor model showed that the relatively small increase of the radial thermal conductivity with increasing foam density can be attributed to interfacial phonon scattering. The foam wall nanoporosity and, to a lesser extent, the orientation of the CNC particles and alignment of the columnar macropores, also influence the insulation performance of the foams. The insight on the importance of phonon scattering for the thermal insulation properties of nanocellulose foams provides useful guidelines for tailoring nanofibrillar foams for super-insulating applications. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies concerning raw flax shives obtained from Polish crop of flax as a loose-fill thermal insulation material. The study focusses mainly on measurements of the thermal conductivity and water vapor permeability of material, but on water absorption and capillary rise as well. The shives showed satisfactory lambda values, comparable to traditional thermal insulation materials. They also showed high mass absorptivity and the ability to uptake large amounts of water by capillary action in a short time. The paper presents also an example of the use of the tested material as thermal insulation of the flat roof. The analysis of the heat flow through the flat roof with different thicknesses of flax shives insulation was carried out. [ABSTRACT FROM AUTHOR]

Nowadays, the research is more focused on natural fibers because of their comparable properties of biodegradability, environment friendly, ease of access, lightweight, and low cost. In this research paper, the effect of chemical treatment on morphological, physical, chemical, mechanical, and thermal properties of pineapple leaf fibers has been studied. Because of the highest amount of cellulosic content, this fiber is having great potential for mechanical and thermal strength. Initially, fibers were extracted using retting and scrapping method and thereafter treatment with different concentrations of alkali was performed. Characterization has been done to analyze its properties and found that the alkaline treatment leads to better mechanical and thermal properties but only up to 7% alkali concentration. After increasing the concentration above 7%, the properties start degrading because of the onset of fiber degradation at higher alkali application. Mercerization helps in making fiber more compatible with hydrophobic matrix resin and hence can be easily reinforced with polymeric matrix for specific composite applications. [ABSTRACT FROM AUTHOR]

For suitable design of equipment and process optimization, the determination of thermophysical properties of the raw materials is necessary. Therefore, this work was aimed at determining and modeling the density, specific heat, thermal diffusivity, and thermal conductivity of acid slurries of cassava bagasse used during its conversion into bioethanol. Experimental measurements were carried out in slurries with different mass fractions of cassava bagasse (0.00 to 0.10) and phosphoric acid (0.00 to 0.10) at temperatures from 278.13 to 318.13 K. Results obtained show that density varied from 986.5 to 1,029.3 kg∙m−3, specific heat from 3,830.0 to 4,142.6 J∙kg−1∙K−1, thermal diffusivity from 0.9624 × 10−7 to 1.5249 × 10−7 m2∙s−1 and thermal conductivity from 0.3825 to 0.6212 W∙m−1∙K−1. While density increased with increasing solids and acid content at decreasing temperature, the thermal properties decreased at higher solids and acid content and increased when heating the slurries. The values were well‐fitted to polynomial models with good accuracy (R2 > 0.921 and MRE < 1.75%), allowing the application of the models to obtain reliable and ready‐to‐use data for cassava bagasse processing. Thus, the data reported in this study can be used for designing and managing momentum, heat and mass transfer processes for enhancing bioethanol production from cassava bagasse. [ABSTRACT FROM AUTHOR]

Phenolic foam (PF) has excellent performance in fire resistance, thermal insulation and other fields. It has the advantages of lightweight, flame retardant, no dropping and low level of toxic gas emission during combustion. In order to learn the relationships between density and properties, PF samples with density of 40, 50 and 60 kg · m−3 were obtained by adjusting the amount of blowing agent. Their micro-characteristics were analyzed with Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscope (SEM) experiments. Mechanical properties were measured with universal extending machine. Thermal properties and stability were tested by laser thermal conductivity analyzer and thermogravimetry analysis (TG), respectively. FT-IR spectra of samples demonstrate that chemical structure will not be affected by the ratio of foaming agent. Higher density comes with better sealing property of the cell holes and leads to better compressive strength. Changing PF density with foaming agent dosage could affect insulation effect, and the sample with density of 60 kg · m−3 showed poor performance compared with the other foams. TG–DTG curves of the PF samples are similar. Evaporation of water, volatilization of phenols and aldehydes, and pyrolysis of surfactant and curing agents are the main reason for the mass loss. Residues of samples increased with the increase in density at 900 °C. Results of this study can clarify that changing the density of PF with amount of foaming agent will not affect its chemical properties, but the ratio has impact on its physical properties. [ABSTRACT FROM AUTHOR]

The article titled "Infill Density Effects on the Mechanical and Thermal Properties of Copper-Plated 3D Printed Parts" explores a solution to the issue of poor mechanical properties in 3D printed plastic parts. The authors suggest that electroplating the parts with a suitable metal coating can improve their mechanical properties. They also propose that adjusting the infill density of the printed parts can enhance structural properties by creating a mechanical interlocking effect. The article highlights the positive impact of these procedures on the thermal properties of the parts as well. The authors of the article are Tommaso Ludergnani, Giulia Fredi, Lorenzo Malagutti, Andrea Balbo, Andrea Dorigato, Francesco Mollica, and Valentina Mazzanti. [Extracted from the article]

C/SiC composites prepared by chemical vapor infiltration technique (CVI) have been regarded as thermal structural materials widely. However, these composites still suffer from poor functional properties like low thermal conductivity, especially in thickness direction of the composites, limiting their large‐scale applications. Herein, mesophase pitch based carbon fiber (MPCF) and continuous wave laser machining were utilized to construct highly effective heat conductive micro‐pipelines within CVI C/SiC composite. The effect of initial density on the final density and thermal conductivity of the as‐obtained MPCF‐C/SiC composites were investigated. The results revealed that higher initial density would directly enhance the thermal conductivity and reduce the negative impact of the bottle‐neck effect. At temperatures between 100°C and 500°C, MPCF‐C/SiC composites preserved more than threefold of the thermal conductivity (340%) when compared to reference C/SiC composites. This work provides a highly effective route for enhancing the thermal conductivity of C/SiC, which would broaden their future applications. [ABSTRACT FROM AUTHOR]

This work deals with the development of a new composite based on mortar reinforced with optimally sized alfa fiber (AF). Experimental investigations of physical and thermo-mechanical properties of the new AF mortar composite are performed for AF weight fraction varying from 0% to 5%. This simple material preparation process is described and scanning electron microscopy (SEM) is undertaken to analyze the morphology of this composite. It shows a random dispersion of the AF into the mortar matrix. Physical properties such as open porosity, water absorption, and bulk density fluctuations with AF mass content are measured. Measured thermal conductivity is compared to the values generated by different prediction models. Good agreement, within 9.6%, is obtained with data predicted by Woodside–Messmer's method. It is demonstrated that this simple blending of AF into mortar improves significantly the thermo-mechanical behavior of the new composite. An addition of 5% of AF weight content makes composite material lighter by about 15%, enhances its insulating thermal capabilities by about 57% and increases its heat diffusion damping rate by about 49%. Moreover, the composite mechanical (flexural and compressive) strength increases by up to 10% for an AF weight content of 1%. [ABSTRACT FROM AUTHOR]

This work provides a method for fabricating rigid polyimide foams via thermal foaming method of nadimide-end-capped polyester-amine oligomer (NPEAO) precursor particles, which were synthesized by reaction of benzophenone-3,3′,4,4′-tetracarboxylic dianhydride and cis-5-norbornene-endo-2,3-dicarboxylic anhydride (NA) with different diamines. The foaming mechanism of the rigid PI foams was systematically investigated. The experiment demonstrates that the pre-treatment of the NPEAO precursor particles and foaming temperature are two pivotal factors that determine the foaming processes. The densities of the prepared rigid PI foams are mainly in the range of 40–200 kg m−3. Moreover, the density and morphology of the PI foams can be effectively controlled by adjusting these two factors. Besides, the obtained rigid PI foams present excellent mechanical and thermal properties, specifically, the flexural and compressive strength reaches as high as to 1.42 MPa and 0.47 MPa, respectively, with the density of 0.076 g cm−3, which are superior to common PI foams and aerogels that of reported in the literature. Therefore, these superior mechanical and thermal properties make obtained rigid PI foams promising candidates as structural materials in the advanced manufacturing industry. [ABSTRACT FROM AUTHOR]

In this study, stability, density, rheology, and thermal conductivity of the Multi-wall carbon nanotubes (MWCNTs) based PCM nanocomposites were experimentally investigated. The PCM OM08 has been selected for the air-conditioning application with a phase change temperature of 8–10 °C. PCM nanocomposites (without surfactant) in various concentrations namely 0.05, 0.1, 0.3 and 0.5 vol. % were prepared using a typical two-step method and high homogenous stability is achieved using a mechanical mixing technique (ultra-sonication). The density of PCM nanocomposites was measured using two different types of standard volumetric flask approach and the experimental values confirmed good conformity with the Pak and Cho mixing theory. The highest thermal conductivity augmentation of 24.03%and 64.04% were achieved in liquid and solid states, respectively, with 0.5 vol. % of MWCNT. While, the addition of MWCNT resulted in a changeover of Newtonian to Non-Newtonian behaviors at a low shear rate, and the dynamic viscosity enhancement was increased by 130% with 0.5 vol. % of MWCNT. Further, the results were compared with existing correlations and it was found that the experimental values were in line with existing correlations. [ABSTRACT FROM AUTHOR]

Expanded polystyrene (EPS) is a commonly used polymer in the packaging industry and for the thermal insulation of buildings. It has poor mechanical properties, which limit its application in some areas. A heat treatment was carried out on a sample of EPS, in order to improve its mechanical properties. The treatment consists of operations that combine the heating and cooling of the material. It is executed to improve the characteristics of the treated polymer and make it more favorable for use in new applications. In the case of EPS, this process changes the behavior of the polymer in a beneficial manner and maximizes its density and hardness. Indeed, the treated version shows interesting mechanical, tribological, and hygroscopic properties. This improvement was obtained mainly due to the morphological modification of the structure of EPS. Indeed, heat treatment leads to the creation of a polystyrene crust, which covers every EPS bead. This crust protects the cell structure of each bead against stretching and supports most of the load applied to the treated version of EPS. Thus, the treated EPS can be used not only for packaging and thermal insulation but also for more structural applications. [ABSTRACT FROM AUTHOR]

Basin and petroleum systems are routinely modelled to provide qualitative and quantitative assessments of a hydrocarbon play. The importance of the rock thermal properties and heat flow density in thermal modelling the history of a basin are well‐known, but little attention is paid to assumptions of the thermal conductivity, present‐day heat flow density and thermal history of basins. Assumed values are often far from measured values when data are available to check parameters, and effective thermal conductivity models prescribed in many basin simulators require improvement. The reconstructed thermal history is often justified by a successful calibration to present‐day temperature and vitrinite reflectance data. However, a successful calibration does not guarantee that the reconstruction history is correct. In this paper, we describe the pitfalls in setting the thermal conductivity and heat flow density in basin models and the typical uncertainties in these parameters, and we estimate the consequences by means of a one‐dimensional model of the super‐deep Tyumen SG‐6 well area that benefits from large amounts of reliable input and calibration data. The results show that the entire approach to present‐day heat flow evaluations needs to be reassessed. Unreliable heat flow density data along with a lack of measurements of rock thermal properties of cores can undermine the quality of basin and petroleum system modelling. [ABSTRACT FROM AUTHOR]

Sound velocities of ammonium nitrate solutions are determined experimentally, with ammonium nitrate concentrations from 25 % to 92 % at initial temperatures from the fudged points to at least 20 °C above. Analytical equations are fitted to the experimental data as well as literature data on densities and specific heats. These equations are used to determine other thermophysical properties such as thermal pressure coefficient and Gruneisen parameter. [ABSTRACT FROM AUTHOR]

(p,ρ,T) data of 1-octyl-3-methylimidazolium tetrafluoroborate [OMIM][BF4] over a wide range of temperatures, from 278.15 to 413.15 K, and pressures, p, up to 140 MPa are reported with an estimated ±0.01–0.08 % experimental relative average percent deviation (APD) in the density. The measurements were performed using an Anton Paar DMA HPM vibration tube densimeter. (p,ρ,T) Data for [OMIM][BF4] was fitted and the parameters of the applied equation were determined as a function of pressure and temperature. After a thorough analysis of literature values and validity of the used equation of state, various thermophysical properties, such as isothermal compressibility, isobaric thermal expansibility, differences in isobaric and isochoric heat capacities, thermal pressure coefficient, internal pressure, heat capacities at constant pressure and volume, speed of sound and isentropic exponent at temperatures in the range 278.15–413.15 K and pressures p up to 140 MPa were calculated.

PVT properties and the thermal-pressure coefficient, γ V = ∂ P / ∂ T V , of 2-propanol have been simultaneously measured in the near- and supercritical regions using high-temperature and high-pressure nearly constant-volume piezo-calorimeter. Measurements were made along 9 liquid and 3 vapor isochores between (234.3 and 697.69) kg·m−3 and at temperatures from (317.17 to 522.36) K at pressures up to 6.05 MPa. For each measured isochore (ρ ), the values of phase transition temperature ( T S ) and pressure ( P S ) at the liquid–gas phase equilibrium curve have been determined using the isochoric P - T break point and thermal-pressure coefficient abruptness techniques. The measured saturated liquid ( ρ S ′ ) and vapor ( ρ S ″ ) densities near the critical point and thermal-pressure coefficient abruptness disappearance were used to estimate the values of the critical parameters ( T C = 508.72 K, P C = 4.840 MPa, and ρ C = 268.82 kg·m−3) of 2-propanol. The expanded uncertainty of the pressure (P ), density (ρ ), and thermal-pressure coefficient ( γ V ) measurements at the 95 % confidence level with a coverage factor of k = 2 are estimated to be 0.05 %, 0.16 %, and 1.5 %, respectively. Scaling-type critical anomaly of the asymptotic behavior of thermal-pressure coefficient in the immediate vicinity of the critical point was experimentally observed. The measured pressures ( PVT ) and thermal-pressure coefficients ( γ V V T ) have been used to calculate of the other key thermodynamic properties such as internal pressure ( P int ), enthalpy ( Δ H vap ) and entropy ( Δ S vap ) of vaporization, saturation ( C sat ), isobaric ( C P ), and isochoric ( C V ) heat capacities. [ABSTRACT FROM AUTHOR]

Physical properties of the tiny scale structures in the cold neutral medium (CNM) of galaxies is a long-standing puzzle. Only a few lines of sights in our Galaxy have been studied with mixed results on the scale-invariant properties of such structures. Moreover, since these studies measure the variation of neutral hydrogen optical depth, they do not directly constrain the density structures. In this paper, we investigate the possibility of measuring the properties of density and spin temperature structures of the H  i from absorption studies of H  i. Our calculations show that irrespective of the thermal properties of the clouds, the scale structure of the H  i column density can be estimated, whereas, H  i absorption studies alone cannot shed much light on either the amplitude of the density fluctuations and their temperature structures. Detailed methodology and calculations with some fiducial examples are presented. [ABSTRACT FROM AUTHOR]

• Compression of water + acetamide mixture were measured. • Measurements were performed at pressures to 100 MPa and temperatures from 278.15 to 323.15 K. • Molar isothermal compression and isobaric expansion of the mixture were evaluated. The density ρ at atmospheric pressure and compression ratios k = Δ V / V o of the {water (1) + acetamide (2)} mixture in the range of temperature from 278.15 K to 323.15 K (278.15, 288.15, 298.15, 308.15, 323.15), pressures from 10 to 100 MPa (10, 25, 50, 75 and 100) and in a wide range of compositions (maximum mole fraction of acetamide (AA) x 2 = 0.3875) were measured in the work. The partial molar volumes of both components V ¯ 1 and V ¯ 2 in the mixture, molar isothermal compression K T , m , molar isobaric thermal expansion E P , m , isochoric coefficient of thermal pressure β V , and internal pressure of the mixture P int were calculated. The volume characteristics for an infinitely dilute AA solution in water: limiting partial molar volumes V ¯ 2 ∞ , limiting partial molar isothermal compression K ¯ T ,2 ∞ , and limiting partial molar isobar expansion E ¯ P ,2 ∞ were calculated. The obtained results are discussed from the standpoint of interactions of solute-solvent and solute-solute. The obtained results are discussed in terms of solute-solvent and solute-solute interactions. [ABSTRACT FROM AUTHOR]

ZrAl3/Al composite fuels (Al‐xZr, x=10, 20, 30, 40, 50, 53 wt.%) were prepared by the non‐consumable arc‐melting technique and close‐coupled gas‐atomization. In order to study the effects of the zirconium content and the oxygen partial pressure on the thermal properties of composite fuels, X‐ray diffraction, scanning electron microscopy, TG‐DTA and DSC were used to characterize the composite fuels, respectively. The result shows that the addition of zirconium leads to the formation of a special structure inside the powder, promoting the oxidation of ZrAl3/Al composite fuels. Besides, non‐selective oxidation of ZrAl3 played an important role in promoting the oxidation process. The oxygen bomb experiment was conducted to evaluate the combustion performance of ZrAl3/Al composite fuels. Oxygen bomb experiments show that the gravimetric combustion enthalpy of the composite fuels decreases linearly with the increase of zirconium content, and increases with the increase of oxygen partial pressure. However, the volumetric combustion enthalpy decreases first and then increases with the increase of zirconium content, and shows a general upward trend when the partial pressure of oxygen reaches 2.5 MPa or more. The pressure curve indicates that the Al‐53Zr composite fuels have the maximum pressure propagation rate (dP/dt)max (which characterizes the maximum flame propagation rate and higher energy releasing rates) in the prepared series of composite fuels. The study demonstrates a complete combustion of ZrAl3/Al composite fuels under high pressure. ZrAl3/Al composite fuels could be considered as a very promising energetic additive in the field of new‐energetic material. [ABSTRACT FROM AUTHOR]