The purpose of this research is to explore the variability on the soil thermal conductivity -after a prescribe fire, and to assess the effects of the ashes on the heat transfer once it’s were incorporated into the soil matrix. Sampling plot was located in the Montgrí Massif (NE of Spain). A set of 42 soil samples between surface and 5 cm depth was collected before and after the fire. To charac...

Measurement of thermal conductivity of rocks is important to understand the thermal properties of earth materials, the characteristics of terrestrial heat flow, and the formation of oil. In this paper we report thermal conductivity, thermal diffusivity, and heat capacity data for 12 conglomerate, sandstone, and gypsum-bearing samples from the Paleogene Kuqa River profile in Kuqa, China. Samples...

The evolution of the thermal conductivities of the unidirectional, 2D woven and 3D braided composites during the CVI (chemical vapor infiltration) process have been numerically studied by the finite element method. The results show that the dual-scale pores play an important role in the thermal conduction of the CVI-densified composites. According to our results, two thermal conductivity models...

The influence of nanopore shapes on the electronic thermal conductivity (ETC) was studied in this paper. It turns out that with same porosity, the ETC will be quite different for different nanopore shapes, caused by the different channel width for different nanopore shapes. With same channel width, the influence of different nanopore shapes can be approximately omitted if the nanopore is small ...

A theoretical model for describing effective thermal conductivity (ETC) of nanocrystalline materials has been proposed, so that the ETC can be easily obtained from its grain size, single crystal thermal conductivity, single crystal phonon mean free path (PMFP), and the Kaptiza thermal resistance. In addition, the relative importance between grain boundaries (GBs) and size effects on the ETC of ...

This study examines the influence of radial thickness on the thermal conductivity of thin metallic wires. While size effects on the electrical conductivity of thin wires have been discussed in the literature, research into size effects on thermal conductivity still requires investigation. At such small length scales, the assumption that the reduced electrical conductivity can be simply related ...

In the present investigation, γ-alumina nanoparticles with particle sizes less than 10 nm, high specific surface area (351 m2/g), high pore volumes and relatively narrow pore sizes distribution was prepared via sol-gel method in presence of aluminum isopropoxide as an aluminum precursor, distilled water, acetic acid as hydrolysis rate controller and tert-butanol as solvent. They had meso ...

Different ancient mortar samples of Pamplona’s San Cernin church have been analyzed to characterize their binder and aggregate fractions. A complete characterization has been carried out including chemical (rapid approximate analysis, soluble salts and trace elements, using traditional chemical procedures, ionic chromatography and spectrophotometry techniques), mineralogical-petrographic (struc...

We present an improved methodology for a thermal transient method enabling simultaneous measurement of thermal conductivity and specific heat of nanoscale structures with one-dimensional heat flow. The temporal response of a sample to finite duration heat pulse inputs for both short (1 ns) and long (5 ls) pulses is analyzed and exploited to deduce the thermal properties. Excellent agreement has...

This is the first comprehensive study on the kinetic modeling of adiabatic decomposition of ditert-butyl peroxide (DTBP) and its solvent mixtures. The adiabatic thermal decomposition of DTBP and its solvent mixtures was examined using an accelerating rate calorimeter under varying thermal inertia. The decomposition products were characterized using gas chromatography-total inorganic carbon anal...