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Advanced NanoMaterials and Technologies for Energy Sector – AdvNanoEnergy – 2018: 2(1) is now released. Thank you for all the contributors and reviewers.

Advanced NanoMaterials and Technologies for Energy Sector – AdvNanoEnergy 2018; Vol 2; Issue 1

Bibliographic Data

Development of nanostructured coatings play a crucial role in surface engineering for energy harvesting applications. Thermal characterization methods are one of the most accessible tools to study, model and predict the process parameters required to control nanostructure development during thermal treatment of different novel multi-material coating systems. Differential scanning calorimetry (DSC) is often used as a standard method to put in evidence different thermal events associated with different processes occurring in the coating materials during nucleation and growth as well as at the substrate/coating interfaces. Thermal analysis of inorganic and hybrid coatings is an essential tool for the validation of the new developed coating processes, allowing to study the reaction chemistry associated with the elimination of solvent compounds, nucleation and crystallization form solution to obtain the desired nanostructures and properties. Once the chemistry of the coating process is established, thermal stability of the coating in the temperature range required for a specific application may be assessed to obtain the desired crystalline phases and avoiding any other subsequent processes producing decomposition, internal stress and delamination of the film. The present paper is a first attempt to show some examples on how thermal analysis methods may be used to assess the thermal behaviour of novel inorganic coatings for developing novel energy harvesting systems.

In this paper, the analysis of the influence of nano-sized defects on the critical current phenomena in the multilayered HTc superconductors is presented. The formation of the pinning potential barrier, determining the superconducting transport current flow, current-voltage characteristics, shapes and critical current limitations are discussed. Various initial positions of pancake vortices in the respect to nano-defects edge, acting as the pinning centers are considered. Influence of this initial position on pinning potential barrier magnitude is regarded. The elasticity forces of the vortex lattice are included into this model. It is considered influence of nano-defects created at fast neutrons irradiation process, arising during the work of the modern nuclear accelerators with superconducting windings and HTc superconducting current leads. Also, defects in the form of micro-cracks created especially during winding of the superconducting coils are considered in this paper. The influence of microscopic defects on the current-voltage characteristics in static and dynamic cases is considered. Attention is devoted to dynamic case, in which interesting phenomenon - peak effect should appear. Influence of nano-defects on the perpendicular to layers Josephson’s currents is regarded. Presented effects influence the work of HTc superconducting cables. The short model of the constructed by author cryocable is presented and progress in this field is briefly reviewed.

Poly methyl methacrylate (PMMA) and Polycarbonate (PC) are low cost polymer materials which can be easily transformed into desired shapes for various applications. However, they have poor mechanical, thermal and electrical properties which are required to be enhanced to widen their scope of applications specifically where along with high strength, rapid heat transfer is essential. Multi Walled Carbon nanotubes (MWCNTs) are excellent new materials having extraordinary mechanical and transport properties. In this paper, we report results of fabricating composites of varying compositions of MWCNTs with PMMA and PC and their thermal conductivity behaviour using simple transient heat flow methods. The samples in disk shapes of around 2 cm diameters and 0.2 cm thickness with MWCNT compositions varying up to 10wt% were fabricated. One end of the disk was exposed to a constant steam temperature while the temperature of the other end was measured for each sample after a time period of 10seconds. The rise in temperature for the specimens was correlated with thermal conductivity which was appropriately calibrated. We found that both PMMA and PC measured high thermal conductivity with increase in the composition of CNTs. The thermal conductivity of 10wt% MWCNT/PMMA composite increased by nearly two times in comparison to pure PMMA while thermal conductivity of 10wt% MWCNT/PC composite specimen increased by nearly four times in comparison to pure PC. This indicates that presence of MWCNTs in minor compositions can significantly affect thermal conductive properties of both PC and PMMA, thereby enabling them for rapid heat dissipating units.