using a magnetic property measurement system (mpms), we measure magnetic susceptibility continuously at frequencies from 0 to 1000 hz for three different superparamagnetic (sp) grain sizes of magnetite (5nm, 7 nm and 10 nm) suspended in hydrocarbons (ferrofluids). our results confirm non-zero values of frequency-dependent susceptibility in the fine tail of nano-sized grains and provide new empi...

The importance of controlling grain boundary (GB) segregation is increasing, especially with the strengthening steel nowadays. In this study, a theoretical prediction method for amount GB solute element in polycrystals established. This entails development nano-polycrystalline model simulating GBs polycrystals, and energy comprehensively calculated all atomic sites constituting by using an inte...

Determination of nano particle size is substantial since the nano particle size exerts a significant effect on various properties of nano materials. Accordingly, proposing non-destructive, accurate and rapid techniques for this aim is of high interest. There are some conventional techniques to investigate the morphology and grain size of nano particles such as scanning electron microscopy (SEM)...

The effects of lithium doping on the sintering and grain growth of non-stoichiometric nano-sized magnesium aluminate spinel were studied using a spark plasma sintering (SPS) apparatus. Li-doped nano-MgO·nAl₂O₃ spinel (n = 1.06 and 1.21) powders containing 0, 0.20, 0.50 or 1.00 at. % Li were synthesized by the solution combustion method and dense specimens were processed using a SPS apparatus at...

The thermoelectric properties of nano-scaled In2O3:Sn films deposited by spray pyrolysis are considered in the present report. It is shown that multicomponent In2O3:Sn-based films are promising material for the application in thermoelectric devices. It is established that the increase in the efficiency of thermoelectric conversion at CSn~5% occurred due to nano-scaled structure of the films stu...

Grain size effects on the physical properties of polycrystalline ferroelectrics have been extensively studied for decades; however there are still major controversies regarding the dependence of the piezoelectric and ferroelectric properties on the grain size. Dense BaTiO3 ceramics with different grain sizes were fabricated by either conventional sintering or spark plasma sintering using micro-...

We report on the thermally induced changes of the nano-structural and optical properties of hydrogenated nanocrystalline silicon in the temperature range 200-700 degrees C. The as-deposited sample has a high crystalline volume fraction of 53% with an average crystallite size of ~3.9 nm, where 66% of the total hydrogen is bonded as identical withSi-H monohydrides on the nano-crystallite surface....

Aluminum Matrix composites (AMCs) are light weight, high-strength materials with potential application in areas such as automobile, aerospace, defence, engineering and other industries. AMCs are projected to significantly reduce the overall weight of the vehicles and aircraft while maintaining satisfactory structural strength. Reinforcement of micron or nano-sized range particles with aluminium...

Porous nano and micro crystalline tin oxide films were deposited by RF Magnetron Sputtering and doctor blade techniques, respectively. Electrical resistance and impedance spectroscopy measurements, as a function of temperature and atmosphere, were performed in order to determine the influence of the microstructure and working conditions over the electrical response of the sensors. The conductiv...