Abstract: Lithium ion batteries have become a popular power source for portable electronic equipments. It is found to be superior in gravimetric energy density as it provides about 1.5 times more energy compared to nickel hydride battery. In this study, Polyethylene Oxide based polymer electrolytes were used for investigation. PEO based solid polymer electrolyte films were prepared by solution casting technique with different concentration of salt and different %wt of zirconia nanofiller. The X-ray diffraction analysis was carried out for the identification of compounds available in the sample and to determine the relative concentrations by the intensities of pattern lines. Also the superposition of absorption bands of specific functional groups was confirmed with the infra-red spectrum of FTIR. The Complex Impedance Spectroscopy technique was further used to measure the cell admittance / impedance in a wide range of frequencies and analyzed in the complex admittance/ impedance plane. From the impedance test results it is observed that the conductivity of polymer electrolyte was improved from 7.39×10−4 Scm−1 to 5.24×10−3 Scm−1 after adding 3%wt of ZrO2 nanofiller with pure polymer. Set up of nano Lab is rare, new and uncommon. It is also an emerging technology. Fabrication of powder needs extra machines which are not popular among common people. It will become popular in the coming future. When particle size is reduced, the quantity of powder is reduced, quality is increased.
Abstract: We confirm piezoelectric performance of bottom electrospun PVDF-TrFE mat is higher than that of top mat and report the mechanism of additional poling process of electrospun nanofibers by local electric field which is originating from residual charges in far-field electrospinning process. Piezoelectric output measurement of poly (vinylidene fluoride-co-trifluoroethylene) electrospun nanofibers was performed by push test and output signals of bottom and top were compared. The local electric field strength calculated by simulation was higher than reported electric field strength of near-field electrospinning (10 MV/m). It can be concluded that the piezoelectric outputs of electrospun nanofibers tend to be improved by residual charge density and electrospinning condition.
Abstract: Composite of Cadmium sulphide (CdS) nanoparticle on the surface of polystyrene- co- maleic anidride (St-co-MMA) were prepared via surfactant free emulsion polymerization. Methylmetacrylate (MMA) was used as auxiliary monomer which co-polymerized with styren (St) and provided the side for coordinating with Cd2+. By the coordination of Cd2+ ions to methyl metacrylate, decoration of the Cd2+ ions on the surface of copolymer were prepared successfully. With the release of S2- ions from the thioacetamide (TAA), CdS was formed on the surface of nanorods copolymer in facile method. Fourier transform infrared spectroscopy (FT-IR) of nanocomposite was confirmed the polymerization of monomers. Structure and morphology of CdS nanoparticles have been characterized using x-ray diffraction (XRD) and scanning electron microscopy (SEM). The XRD measurements suggest the cubic structure for CdS and the particles size was estimated to about 3.35 nm by applying Scherrer’s equation. The SEM analysis confirmed the nanorode structure of CdS/ (St-co-MMA) composite. The photoluminescence (PL) and UV–Vis spectroscopy revealed the quantum confinement effect in the CdS/ (St-co-MMA) nanocomposite. Using effective mass approximation (EMA) method particle sizes were calculated from the shift in optical band gap. The thermal properties of the CdS/ (MMA-co-St) were explored by thermal gravimetric analysis (TGA). The improved thermal stability of nanocomposite was attributed to the interaction of CdS nanoparticles with polymer. The CdS/ (MMA-co-St) nanocomposite exhibited a glass transition temperature around 250◦C.
Abstract: Magnetite nanofluid has been prepared in citric acid based medium. Their stability and polydispersity level have been characterized by UV-visible spectrophotometry.The volumetric properties such as apparent molar volume, partial molar volume and isentropic compressibility of nanofluid have been measured at temperature range from 298.15K to 313.15K at atmospheric pressure. The obtained results were interpreted in terms of particle-particle and particle-fluid interactions, and compared with commercially available magnetite nanofluid in terms of particle size difference. It was observed that the influence of particle size on measured volumetric parameters is significant for any practical applications of fluid flow. The differences in measured quantities were determined qualitatively by considering the state of aggregation / particle size distribution of the nanofluids.
Abstract: High resolution pattern of silver nanoparticles has received great attentions for its application in various electronic devices such as touch screen, OLED and solar cell. However, traditional printing techniques cannot meet the demands for high resolution. Here, we introduce a new method to prepare fine lines of nanoparticles less than 10 μm by microcontact printing (μCP), which was first used to surface modification and patterning. The PDMS stamp with 10 μm line width and space was prepared by replication of etched silicon template. Conductive silver ink was transferred from resource substrate to the target substrate using the PDMS stamp during μCP process. Transferred line patterns of silver nanoparticles were conductive and the resistance was about 100 Ω using two-point probe measure method after baking at 150°C for 30 min. We found that printing pressure imposed on the PDMS stamp was significant for the quality of lines during the μCP process and appropriate printing pressure was 7~9 KPa. The technology can be used as universal method to transfer other nanomaterials and create fine patterns with a simple and cost-effective manner.
Abstract: In this present work, the experimental study of developing the smart material by using 2 different preparation methods for developing nanomaterial for Glass fiber reinforced polymers (GFRP) in order to determine the structural damage. The first method deals with the development of Fiber mat using PVA-CNF (Poly vinyl Alcohol-Carbon nanoFiber) and PVA-CNT (Poly vinyl Alcohol – Carbon nanoTube) , which is embedded into the GFRP. Second method deals with the dispersion of both CNF and MWCNT with epoxy matrix (sonication process) to manufacture GFRP by using Vacuum Resin Transfer Molding (VARTM) process. Embedding CNT and CNF fiber is easy which does not downgrade the material’s mechanical properties. PVA-CNF and PVA-CNT sensors were placed at various orientations and different wt. % of CNT and CNF fiber mat were manufacture and embedded on the GFRP has been done in first method, and in the second method, dispersion of the CNF-MWCNT with various wt. % in the GFRP composite has been done. The various incremental loading-unloading step had been applied to the manufactured specimens and their corresponding electrical resistance were observed. The electrical conductivity of the fiber sensor and nanomatrix were compared, due to its resistivity effect on the specimens will be monitored and simultaneously the potential for stress/strain and damage monitoring during the mechanical tests can be assessed.
Abstract: The study considers the challenge of improving the efficiency of dry finishing and semi-finishing turning of (P10-P20) steel with carbide tools with complex composition coatings by directed selection of the composition and properties of the coatings through the control of the parameters of the filtered cathodic vacuum-arc deposition (FCVAD). The conducted tests have confirmed the feasibility and effectiveness of the control of compositions, structures, and properties of complex composite coatings of Ti-TiN-TiAlN type by varying the parameters of the FCVAD process. In particular, it has been found out that the ratio of Ti/Al, which greatly affects the important properties of the coating (grain size, lattice parameter, microhardness, fracture toughness, etc.), can be changed at constant compositions of cathodes by varying such parameters of coating synthesis as titanium cathode arc current, nitrogen pressure, and substrate shear stress. It has been shown that Ti-TiN-TiAlN coating produced at different values of the parameters of synthesis significantly changes the cutting properties of carbide tool and thus allows optimizing the coating composition for a variety of machining conditions.The developed methods are also applicable for multi-component complex composite coatings.
Abstract: Heat transfer development has encouraged researcher in recent decades to develop concepts and technologies promoted by manufactures of ultra compact, miniaturized the heat transfer application. In thermal engineering lots of particle are being used for heat transfer application astonishing potential of hybrid nanoparticles. Amalgamation of hybrid nanoparticles has increasing interest in heat transfer enhancement. In this research mixture of hybrid nanoparticle was prepared using Aluminum Oxide (Al2O3) and Copper (Cu) in different proportion in order to increase thermal conductivity. Two tests of X-Ray Diffraction (XRD) and Field Emission Scanning Electron Microscopy (FESEM) analysis were carried out. The heat transfer development was found in the hybrid nanoparticles mixed with water and tested in shell and tube heat exchanger and found that the enhancement is more with nanofluid when compared to water alone. Hybrid nanoparticles form immediate precipitate when it was used in any mechanical applications and it characterised by an improvement of base particles like nanoparticles of metals, metal oxides and carbides.
Abstract: In this communication we report on the optical property of CuO nanoparticles prepared by cost effective, simplistic and environment-friendly sol-gel technique on borosilicate glass by dip coating. The particle size was analyzed by Transmission Electron Microscope (TEM) which depicted particle size of CuO ~ 5 nm. To understand the optical behavior of nanosized CuO particles on borosilicate glass tube UV-visible spectrum has been taken. Effective mass model calculations determined the size of particles as 2.26 nm, which supports the TEM analysis. Samples were also analyzed by Fourier transform infrared spectrum (FT-IR) to understand the chemical bond in detail.
Abstract: In this research, reduced graphene oxide/zinc oxide nanocomposites (rGO/ZnO) were synthesized at different pHs (9, 10, 11 and 12) by using one-pot hydrothermal bath method., The obtained nanocomposites characterized by using X-ray diffractometer, Fourier transform infrared, Raman, scanning electronic microscope and diffuse reflection spectroscopy techniques. Photocatalytic activity of nanocomposites were evaluated by monitoring the photodegradation of 4-nitrophenol (4-NP) in water exposed to ultraviolet and visible light irradiation. The morphological and structural results have been shown that at pHs of 9 and 10, the ZnO nearly aggregated nanoparticle are crystalized, while at higher pHs (11 and 12), the preferential growth of ZnO in the form of nanorods is seen. Comparative studies on photocatalytic performance of the nanocomposites shows that ZnO nanorods have better photocatalytic activities than the others.