An improved thermal-needle approach for accurate and fast measurement of thermal conductivity of aqueous and soft biomaterials was developed using microfabricated thermal conductivity sensors. This microscopic measuring device was comprehensively characterized at temperatures from 0 °C to 40 °C. Despite the previous belief, system calibration constant was observed to be highly temperature-depen...

We report the first experimental results on the temperature dependent in-plane and cross-plane thermal conductivities of a symmetrically strained Si/Ge superlattice and a Ge quantum-dot superlattice measured by the two-wire 3 omega method. The measured thermal conductivity values are highly anisotropic and are significantly reduced compared to the bulk thermal conductivity of the structures. Th...

The design and optimization of micromachined thermal sensors often requires information on accurate material properties of the used thin-films. These data can differ considerably from those stated for bulk matter and are strongly process-dependent. In this contribution a micromachined canitlever structure is proposed, which allows to directly determine the thermal conductivity of dielectric thi...

Knowledge of the ground thermal conductivity is of importance when designing borehole heat exchanger (BHE) systems. As thermal conductivity for any specific rock type varies due to its mineral content, porosity, pore fluid and anisotropy, it is preferable determined in-situ. Choudhary (1976) suggested a method for determining the thermal conductivity which analysed the heat transfer during the ...

The thermal conductivity of MOF-5 single crystals is measured over a wide temperature range between 6 K and 300 K, using the longitudinal, steady-state heat flow method. Between 6 K and 20 K, the thermal conductivity increases with the increase in temperature and exhibits a peak near 20 K. This peak results from the crossover between the decreasing mean free path and the increasing phonon speci...

The study of graphene thermal conductivity is of great importance, as its anomalous thermal and electrical conductivities (the largest among the all known materials so far) provide very good perspectives for graphene-based nanoelectronics devices. Thermal conductivity of graphene is phonon-based, since its electronic-based thermal conductivity represents less than 1% of the total thermal conduc...

In recent decade, the new advanced nanofluids, composed from various particles, have attracted the attention of researchers. This class of nanofluids, which can be prepared by suspending several types (two or more than two) of nanoparticles in base fluid, is termed as hybrid nanofluids. In this work, an experimental investigation on the effects of temperature and concentration of nanoparticles ...

In this study the thermal conductivity and the volumetric heat capacity of non-Newtonian fluids are investigated. These fluids find many applications in chemical, medical and food industries. They mostly have viscoelastic behavior and generally differ from Newtonian fluids. Two non-Newtonian fluids, solutions of xanthan and carboxy methyl cellulose in water with various concentrations have bee...