Frequency-domain thermoreflectance is extended to the characterization of thin metals films on low thermal diffusivity substrates. We show how a single noncontact measurement can yield both the thickness and thermal conductivity of a thin metal film with high accuracy. Results are presented from measurements of gold and aluminum films 20–100 nm thick on fused silica substrate. The thickness mea...

We show the well-posedness of the conductivity image reconstruction problem with a single set of interior electrical current data and boundary conductivity data. Isotropic conductivity is considered in two space dimensions. Uniqueness for similar conductivity reconstruction problems has been known for several cases. However, the existence and the stability are obtained in this paper for the fir...

The paper presents experimental studies of dielectric properties of nanofluids based on ethylene glycol and SC-TiO2 nanoparticles with average size of 15-40 nm with various mass concentrations. The dielectric permittivity both real part and imaginary part as a function of temperature and frequency were measured. Also, dependence ac conductivity on frequency, temperature, and mass concentration ...

Extreme non-Arrhenius dependence of the ionic conductivity in optimized fast ion conducting glasses has been observed. When all the chemical factors controlling the ionic conductivity in glass have been optimized, the conductivity fails to reach the values expected, >0.1 (Ωcm)−1 at 298 K. A new series of glasses zAgI+(1−z) [0.525Ag2S+0.475B2S3:SiS2] have been measured for the first time and are...

In this investigation the silicate nano structure of MCM-41 has been used for the production of nanofluid. The particles have negligible heat conductivity and therefore by their dispersion in a base fluid like water, it is possible to study the increase of heat conductivity due to the Brownian motion effects. In this work a suitable apparatus for the measurement of heat conductivity has been bu...

Conductivity is regard as a key technical parameter in modern intensive fish farming management. The water conductivity sensors are sophisticated devices used in the aquaculture monitoring field to understand the effects of climate changes on fish ponds. In this paper a new four-electrode smart sensor is proposed for water conductivity measurements of aquaculture monitoring.The main advantages ...

We present a new three-dimensional steady-state saturated groundwater-flow forward-simulator with full conductivity tensors using a nineteen-points block-centered finite-difference method. Hydraulic conductivity tensors are defined at the block interfaces eliminating the need to average conductivity tensors at adjacent blocks to approximate their values at the interfaces. The capabilities of th...

We consider a reconstruction formula for the internal conductivity and uniqueness of conductivity in magnetic resonance electrical impedance tomography (MREIT) which aims to reconstruct the conductivity distribution using internal current distribution. We provide a counter-example of uniqueness for a single measurement of current density with Neumann boundary data and show that at least two mea...

Very large thermal conductivity enhancement had been reported earlier in colloidal suspensions of solid nanoparticles (i.e., nanofluids) and more recently also in oil-in-water emulsions. In this study, nanoemulsions of alcohol and polyalphaolefin (PAO) are spontaneously generated by self-assembly, and their thermal conductivity and viscosity are investigated experimentally. Alcohol and PAO have...