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At high temperatures, our results are at variance with some literature that indicate a ‘strongly’ decreasing thermal conductivity or an essentially ‘temperature independent’ thermal conductivity.
A material that has a good thermal conductivity, low cost, but also resistance is the desired.
We show that this is the principal factor for the very low thermal conductivity.
The results proved that the thermal conductivity can be improved substantially by...
The results indicate that the effective thermal conductivity distribution greatly depends on Kapitza thermal resistance, particle size, and degree of material gradient.
The measurements show that both purity and thermal treatment strongly influence the value of thermal conductivity.
This plot allows researchers to quickly distinguish materials where the thermal conductivity has been optimized from those where improvement can be made.
An explicit dependence of contact conductance on temperature was not seen to be necessary as long as the changes in the hardness and thermal conductivity of the material with temperature are incorporated in the correlation.
The predictions of an effective thermal conductivity agree with the experimental data.

Related Questions

What factors affect the thermal conductivity of different materials?4 answersFactors that affect the thermal conductivity of different materials include moisture content, temperature difference, bulk density, airflow velocity, thickness, pressure, and material aging. The length of the crystal lattice is a primary factor that influences the thermal conductivity of graphene, while the edge termination state has little effect. Temperature and moisture content are relevant factors that can cause variability in thermal conductivity, with inorganic fibers showing a linear temperature dependence and foamed insulation materials exhibiting nonlinear behavior. The presence of a graphite coating on a sample and the thickness of the sample can also affect the measurements of thermal conductivity, with deviations ranging from 5.5% to 60% depending on the material's thermal conductivity coefficient and the thickness of the coating.
What are the factors that affect the thermal conductivity of a material?5 answersFactors that affect the thermal conductivity of a material include moisture content, temperature difference, bulk density, airflow velocity, thickness, pressure, and material aging. The thermal conductivity of materials can also vary depending on their composition, such as inorganic fibers like rockwool or fiberglass showing lower thermal conductivities at lower temperatures, and foamed insulation materials like polyisocyanurate exhibiting nonlinear temperature dependence. Additionally, the thermal conductivity of a material can be influenced by factors such as the specific gravity, viscosity of fluid, porosity, and particle size. Understanding these factors is crucial for selecting and designing thermal insulation materials for building envelopes and achieving energy-efficient designs.
What is the thermal conductivity of KF?5 answersThe thermal conductivity of KF has been studied in several papers. Experimental measurements using the steady-state variable gap technique were performed on eutectic LiF-NaF-KF, which showed a weak negative deviation of thermal conductivity with temperature. Molecular dynamics simulations using the Green-Kubo method predicted the thermal conductivities of molten alkali fluorides, including KF, and their mixtures. These simulations found that the thermal conductivity follows a scaling law for most systems, but a significant departure from the scaling law was observed in LiF-KF and LiF-NaF-KF mixtures. Another study used the plane heat-wave technique to measure the thermal conductivity of KF at ambient temperatures and pressures up to 3.8 GPa, finding that the effect of optic phonons in KF is negligible. However, the specific conductivity of the KF-K2TaF7 system was found to decrease with the addition of K2TaF7.
How thermally conductive is wood?7 answers
What is considered high thermal conductivity?10 answers
Which material has a lower thermal conductivity than rockwool?7 answers

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Characterization of Thermo-Mechanical Biodegradable Material for Insulation in Buildings ?
5 answers
The characterization of thermo-mechanical biodegradable materials for insulation in buildings is crucial for enhancing energy efficiency and reducing environmental impact. Bio-based insulation materials, such as those derived from recycled rubber, wood fibers, cellulose fibers, date palm waste, and cardboard, offer promising properties for sustainable construction. These materials exhibit good thermal performance, moisture buffering capacity, and high vapor permeability, although they may be susceptible to moisture. Studies emphasize the importance of considering not only thermal conductivity but also parameters like thermal capacity, lifetime, and environmental impacts when characterizing these materials. Incorporating locally sourced natural and recycled materials in insulation products can significantly improve energy efficiency and environmental sustainability in buildings. Further research is needed to comprehensively compare the properties of different insulation materials for optimal building performance.
Why commercial caco3 is stable at nano size and can be used in many application ?
5 answers
Commercial calcium carbonate (CaCO3) stabilized at the nano size is stable and versatile due to its unique properties. Studies have shown that CaCO3 nanoparticles exhibit biocompatibility, digestibility, and stimuli-responsiveness, making them suitable for various applications. The formation of submicron-sized CaCO3 particles through aerosol methods results in stable calcite phase structures, enhancing their stability and applicability. Additionally, the use of surfactants and porous membranes in wet carbonation processes aids in producing nano-sized CaCO3 particles with high surface areas, enabling efficient adsorption capabilities. The controlled microstructure of CaCO3 nanoparticles in Pickering emulsions allows for the encapsulation and delivery of lipophilic drugs, showcasing their potential in pharmaceutical and biomedical applications. These findings collectively highlight the stability and diverse applications of commercial CaCO3 nanoparticles at the nano size.
Is commercial caco3 stable at nano size and can be used in many application ?
5 answers
Commercial calcium carbonate (CaCO3) stabilized at nano size exhibits stability and versatility for various applications. Studies show that CaCO3 nanoparticles can be utilized in fields like food, pharmaceuticals, and biomedicine due to their biocompatibility and stimuli-responsive properties. Additionally, surface-modified nanoCaCO3 in polymer matrices enhances thermal stability and dispersion, making them suitable for interior waterborne decorative paints. Controlled synthesis and surface modification methods have advanced the use of CaCO3 in nanostructured materials, improving mechanical, optical, and catalytic properties for biomaterials, environmental remediation, and energy applications. The stability and diverse applications of commercial nano-sized CaCO3 make it a promising candidate for various industries.
What is odd-even effect?
5 answers
The odd-even effect refers to the alternation in properties based on the number of carbon atoms in a molecule. This phenomenon has been observed in various systems such as organic molecules, polymers, and even in magnon spin transport. In the context of nonconjugated tetraphenylalkanes, an excited-state odd-even effect was discovered, where molecules with an even number of alkyl carbon atoms exhibited strong through-space interaction and high emission, unlike those with odd numbers. Similarly, in the study of n-alkanes, an odd-even alternation was observed in properties like melting point, density, and molecular dynamics, with anomalous behavior noted in heptane. Furthermore, in the design of polymers, a significant odd-even effect was found based on the ethylene linker length, impacting liquid crystal formation, density, and thermal conductivity.
Is there any problem with Tween 20 and arenediazonium salts in electrochemical experiments?
5 answers
In electrochemical experiments, Tween 20 does not pose a problem when used with arenediazonium salts. Tween 20 is a nonionic surfactant commonly employed in various applications, including electrochemical studies. Additionally, arenediazonium salts, specifically tetrafluoroborate salts, are generally stable for handling in such experiments. Moreover, the modification of solid carbon-containing electrochemical sensors with arenediazonium salts has been shown to enhance the sensitivity of detecting metal ions like copper and mercury in complex matrices like human hair. Therefore, the combination of Tween 20 and arenediazonium salts can be effectively utilized in electrochemical experiments without significant issues, offering opportunities for diverse applications in analytical chemistry and sensor development.
How much DISSOLVED OXYGEN INCREASED BY Chlorella vulgaris and Spirulina platensisPHYCOREMEDIATION?
5 answers
Chlorella vulgaris and Spirulina platensis have shown significant improvements in dissolved oxygen levels during phycoremediation processes. In the study by Atoku et al., it was observed that after 45 days of treatment with these microalgae, the dissolved oxygen levels increased due to the removal of heavy metals from industrial wastewater. Additionally, the research by Madadi et al. demonstrated that when C. vulgaris was cultivated in diluted petrochemical wastewater, there was a notable increase in the removal of pollutants like BOD and COD, indicating an improvement in water quality which could lead to an increase in dissolved oxygen levels. These findings highlight the potential of Chlorella vulgaris and Spirulina platensis in enhancing dissolved oxygen concentrations through their phycoremediation activities.
When was SAPO-37 first synthesized?
5 answers
SAPO-37 was first synthesized by utilizing a faujasite-type microporous SAPO-37 precursor, leading to the creation of unique mesoporous silicoaluminophosphate (MESO-SAPO-37) with uniform 3 nm pores. The synthesis of SAPO-37 requires specific conditions, such as a narrow pH range of 8 to 9 and the presence of silica species in the reactant gel, as silica is crucial for SAPO-37 formation. Studies on SAPO-37 samples with varying Si atomic fractions revealed that the highest amount of acid centers and hydroxyls were present when the silicon atomic fraction was around 0.12–0.13, indicating the optimal conditions for SAPO-37 synthesis. Additionally, the characterization of intermediate phases during SAPO-37 synthesis highlighted the importance of controlled heating to prevent structural defects and maintain crystallinity. The introduction of copper into SAPO-37 through solid-state ion exchange facilitated the synthesis of Cu-SAPO-37 catalysts with high selectivity for specific reactions, demonstrating the versatility of SAPO-37 in catalytic applications.
What does the hydrodynamic phonon regime in 2D materials look like?
5 answers
The hydrodynamic phonon regime in 2D materials exhibits unique characteristics such as long-range interactions, large phonon lifetimes, and diverse convergence behaviors in thermal conductivity. Studies on graphene and silicene show that the dominance of normal scattering processes leads to hydrodynamic phonon transport, resulting in extended phonon lifetimes and long-range interactions, absent in bulk silicon. Additionally, research on transient heat conduction in 2D materials demonstrates the existence of hydrodynamic phonon transport in a two-dimensional disk geometry, with the potential for observing this phenomenon in suspended graphene disks within specific temperature ranges. Furthermore, the derivation of a Guyer-Krumhansl-like equation highlights the presence of heat current vortices and negative non-local thermal conductance in 2D materials, showcasing universal transport behaviors in hydrodynamics.
What are the potential applications of laser ablation in creating nanoparticles for soil targeting?
5 answers
Laser ablation in liquids is a promising technique for producing nanoparticles with potential applications in soil targeting. Studies have shown that laser ablation can be utilized to create various nanoparticles such as vanadium pentoxide (V2O5), gold, NiFe2O4 (NFO) and CoFe2O4 (CFO), copper, and other metallic nanoparticles. These nanoparticles can exhibit properties like superparamagnetism, high absorbance in the visible range, and stability, making them suitable for soil-related applications. The nanoparticles produced through laser ablation can potentially be used in soil remediation, nutrient delivery, or even as sensors for monitoring soil conditions. The controlled synthesis and unique characteristics of nanoparticles generated via laser ablation offer a promising avenue for developing innovative solutions for soil targeting applications.
What percentage of co2 absorption with different types of amines ?
5 answers
The percentage of CO2 absorption varies with different types of amines. In the studies, it was found that primary and secondary amines like MEA, PZ, 2PE, and HPZ achieved CO2 loadings of 1.06, 1.14, 1.13, and 1.18 mol CO2/mol amine, respectively. Additionally, tertiary amines such as MDEA and TEA showed absorption rates of 14.2 and 9.8 mmol CO2·L−1·min−1, respectively, in specific conditions. Moreover, single-component absorbents like 2-(methylamino)ethanol and others demonstrated CO2 capture efficiencies exceeding 90% in various experimental setups. Furthermore, mixed amines, particularly MEA combined with AMP, exhibited optimal CO2 absorption performance with an absorption efficiency of 100% and an overall mass transfer coefficient of 1.540 l/s.
What are the key rubber material properties that influence the performance characteristics (e.g., strength, durability) of the current product?
5 answers
The key rubber material properties influencing performance characteristics like strength and durability of rubber products include thermal conductivity, specific heat, thermal diffusivity, viscoelastic properties, crosslinking rate, tensile strength, modulus, tear resistance, and resistance to shear stresses. These properties are crucial for product design and manufacturing processes. Factors such as temperature, environmental effects, rubber formulation, and curing conditions significantly impact these properties. Advanced techniques like Molecular Dynamics simulations aid in predicting thermodynamic and viscoelastic properties, enabling the design of novel rubber materials with optimized mechanical properties. The structure-property relationships at both macroscopic and microscopic levels play a vital role in understanding and enhancing the performance of rubber products.