jrups
Abstract : A Review on Carbon Nanotubes: Preparation, Properties and Applications
|
|
Abstract: Carbon nanotubes(CNTs) have achieved attention in recent times because of their extraordinary physicochemical properties like strength, flexibility, sensors, conducting etc. Carbon nanotubes(CNTs) are known as nano-architectured allotropes of carbon, having graphene sheets which are rolled up into cylinder that forms carbon nanotubes. In the field of nanotechnology, carbon nanotubes are the one of the most unique invention. The eye-catching features of carbon nanotubes are their electronic, mechanical, optical and chemical characteristics, which open a way to future applications. Carbon nanotubes can be single walled and multi walled which can be produced in various ways. The most common techniques used nowadays are: arc discharge, laser ablation and chemical vapour deposition. In this review article,the applications of CNTs in various technologically important fields are discussed in detail. Keywords: Nanotubes, Nanotechnology, SWCNTs and MWCNTs, Nanomedicine, Graphene, Nanocapsule. |
Abstract : Color and Fastness Properties of Woven Stretchable Fabrics
|
|
Abstract: Stretchable fabrics have gained much interest in the last few years because their higher comforts and aesthetic properties. The main parameters which control the stretchable fabric properties were found to be spandex linear density and draft ratio. In this research paper, the influences of these variables on color properties of stretchable fabrics were investigated. Color properties of the stretchable fabrics were characterized by whiteness index, K/S values, and colorfastness to washing, rubbing and perspiration. The results of this work showed that color properties of the stretchable woven fabrics were affected byindependent variables. Generally, impact of spandex draft ratio on color properties was more pronounced than the effects of spandex linear density. Keywords: Stretchable fabrics, Spandex, Draft ratio, Linear density, Color strength, Whiteness index. |
Abstract : Peculiarities of The Orientational State of Liquid-Crystal Completely Aromatic Thermotropic Copolymer
|
|
Abstract: Polarization far-IR spectroscopy has been used to carry out a comparative study of the spectra of granules and fibers of completely aromatic thermotropic liquid-crystal copolymer Vectra A950. The analysis of terahertz polarization IR spectra Vectra A950 showed that in contrast to the mid-IR, dichroic ratio of the absorption bands in the spectra of fibers and granules, substantially different. It is shown that the difference between the value and the orientation order parameter in the samples is determined by and correlated with the intensity of the local dynamics of polymer chains, such as the librational mobility of phenylene and naphthalene rings of the copolymer mesogens. The results suggest the possibility carrying out an independent evaluation of the spectroscopic parameters reflecting the properties of intermolecular interactions in oriented the liquid-crystalline polymers for their low-frequency spectra. Keywords: Liquid-crystal polymers, far-infrared spectroscopy, local dynamics, orientation order. |
Abstract : Morphological, Thermal and Electrical Properties of (PEO/PVP)/Au Nanocomposite Before and After Gamma-Irradiation
|
|
Abstract: Gold nanoparticles (Au NPs) have been successfully biosynthesized by Chenopodium murale (C. murale) leaf extract. Au NPs were incorporated within polyethylene oxide (PEO)/polyvinyl pyrrolidone (PVP) polymer blend by casting method. Scanning electron microscope (SEM), Differential scanning calorimetry (DSC), and DC electrical resistivity were used to investigate the morphological, thermal, and electrical properties of blend/Au nanocomposite before and after gamma-irradiation at different doses (1, 2, 3, 4 and 5 MR).SEM micrographs confirmed the dispersion of Au NPs within the polymeric matrix due to effect of irradiation process. DSC analysis showed that the thermal stability for irradiated samples was improved as compared with pure blend and its nanocomposite. DC measurements revealed nonlinear behavior for electrical resistivity versus temperature. The electrical resistivity values for blend/Au nanocopmosite and its high irradiated samples were less compared to pure blend. Keywords: Gamma-irradiation, Au NPs, SEM, DSC, electrical resistivity. |
