S.T. Leong; Y. Yusof; C.F. Tan
Abstract
The present work focuses on determination of tensile properties of stone wool fiber reinforced high density polyethylene composites by two methods: experimental and finite element analysis. Four weight percentage of stone wool (SW) fiber 10 – 40 wt. % were chosen. The samples of composites were ...
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The present work focuses on determination of tensile properties of stone wool fiber reinforced high density polyethylene composites by two methods: experimental and finite element analysis. Four weight percentage of stone wool (SW) fiber 10 – 40 wt. % were chosen. The samples of composites were made by using the hot press technique. ASTM D638 was used to test the composite samples. Scanning electron microscopy analysis was carried out on the fractured surface to observe the interaction between matrix and fiber in the composites. Significant improvement of tensile properties was observed and recorded from the composites with SW weight percentage of 20 wt. %. The yield strength, tensile strength and tensile modulus increased by 8.1%, 23.0% and 37.8% over pure HDPE. ANSYS tensile models were then established to understand better the processing and behavior phenomenon. The numerical results obtained were in good agreement with the experimental results, with an accuracy of more than 90%.
Lalit Sharma; Partheepan Ganesan; Ranjit Kumar; T.D. Senguttuvan; Vidya N. Singh
Abstract
Due to high dielectric constant, Pr6O11 is viewed as a prospective gate dielectric material in decanano metal-oxide-semiconductor devices. In this study, structural, optical and dielectric properties of Pr6O11 nanorods have been investigated for its possible application as gate dielectric materials for ...
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Due to high dielectric constant, Pr6O11 is viewed as a prospective gate dielectric material in decanano metal-oxide-semiconductor devices. In this study, structural, optical and dielectric properties of Pr6O11 nanorods have been investigated for its possible application as gate dielectric materials for the future generation optoelectronic devices. Pr(OH)3 nanorod structure was synthesized in an alkaline medium (KOH and NaOH) at a moderate temperature (~188°C) and atmospheric pressure. The Pr(OH)3 nanorods were converted to Pr6O11 nanorods by annealing them at 400°C. XRD studies showed that both Pr(OH)3, as well as Pr6O11, were highly crystalline. TEM studied showed that the diameter and length of nanorods were ~30 nm and 100 nm, respectively. Optical studies showed that the band gap of these nanorods is 5.31eV. Dielectric studies showed that dielectric constant at 1 kHz is ~ 4000.
Ashwani Kumar; Surya Kant Tripathi; Abhay D. Deshmukh
Abstract
In the present study, synthesis, characterization, of dual mode emission (Up and downconversion) in lanthanide-doped NaYF4 nanorods is presented. The unique and rich energy-level structure of these lanthanide ions allows for efficient spectral conversion, including up and downconversion processes mediated ...
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In the present study, synthesis, characterization, of dual mode emission (Up and downconversion) in lanthanide-doped NaYF4 nanorods is presented. The unique and rich energy-level structure of these lanthanide ions allows for efficient spectral conversion, including up and downconversion processes mediated by resonant energy transfer between neighboring lanthanide ions. The careful examination of nanorods indicates the perfect uniformity, monodispersity and well defined crystallographic facets. Er 3 + , Yb 3 + doped NCs exhibit green/red dual mode emission with low power density. As solar cells have majority of losses due to spectral mismatch, so with the help of these dual mode emission of nanorods can be utilized as up/down converter to increase the efficiency solar cell.
Sushilkumar A. Jadhav
Abstract
Nanomaterials of interesting shapes such as nanostars, nanodiscs, nanorods and nanoflowers are frequently synthesized by chemists, experimental physicists and material scientists nowadays. Large number of the bottom-up or top-down synthetic techniques are invented and reported for the synthesis of these ...
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Nanomaterials of interesting shapes such as nanostars, nanodiscs, nanorods and nanoflowers are frequently synthesized by chemists, experimental physicists and material scientists nowadays. Large number of the bottom-up or top-down synthetic techniques are invented and reported for the synthesis of these materials with interesting shapes. Such shapes found to already exist in nature. The great nature has done this nano artwork with its power and unbeatable architectural skills at molecular level. The ultimate aim of the synthesis techniques invented may not be to mimic nature or challenge it but instead to explore the use of these variously shaped nanomaterials in technological and biomedical applications. These materials found to be applicable in their use as drug delivery systems, catalysis, and energy and as biosensors. In the present note some of the recent examples of such materials are discussed with their images taken with high resolution microscopes.
Jasneet Kaur; Jaspreet Kaur; R. K. Kotnala; Vinay Gupta; Kuldeep Chand Verma
Abstract
In the present work, the self-assembly of Co 2+ and Fe 3+ doped SnO2 nanoparticles (Co and Fe = 5 mol% each) into nanorods by co-doping of Ce 3+ (4 mol%) ions is studied. The nanorods are prepared by a chemical route using polyvinyl alcohol as surfactant with the composition Sn0.91Co0.05Ce0.04O2 (SCC54) ...
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In the present work, the self-assembly of Co 2+ and Fe 3+ doped SnO2 nanoparticles (Co and Fe = 5 mol% each) into nanorods by co-doping of Ce 3+ (4 mol%) ions is studied. The nanorods are prepared by a chemical route using polyvinyl alcohol as surfactant with the composition Sn0.91Co0.05Ce0.04O2 (SCC54) and Sn0.91Fe0.05Ce0.04O2 (SFC54). The X-ray diffraction (XRD), transmission electron microscopy (TEM), magnetic and electrical measurements are used to characterize these nanorods. The XRD pattern show the tetragonal rutile and polycrystalline nature of SnO2 nanorods which is also confirmed by TEM. The TEM images exhibit that the diameter of SCC54 nanorods lie in the range of 15-20 nm, length~100-200 nm whereas for SFC54 specimen, diameter ~5-15 nm and length ~50-100 nm. In our previous work, we fabricated Co and Fe (3 and 5 mol% each) doped SnO2 nanoparticles which exhibited high ferromagnetism. It is observed that on Ce 3+ co-doping, nanoparticles assembled themselves into rod like structures and the values of saturation magnetization and dielectric properties have further enhanced. Thus the nature and the concentration of dopants are found to play crucial role in tuning the morphology, magnetic and electrical properties of nanostructures. The values of saturated magnetization (Ms) are 1.14 and 0.14 emu/g and coercive field are 112 and 42 Oe, in SCC54 and SFC54 specimen, respectively, at room temperature. The variation in dielectric behavior is attributed due to the interface polarization. However, in lower frequency regime, the decreasing trend of dielectric permittivity with increasing frequency is explained by the Maxwell-Wagner theory and Koops’ model, whereas, in higher frequency region, the resonant behavior is observed due to nano size effect.
Faheem Ahmed; Shalendra Kumar; Nishat Arshi; Ram Prakash
Abstract
ZnO nanorods with diameter 90-100 nm range (tip diameter~15 nm) and length of about 2 μm have been prepared using microwave irradiation technique. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results indicate that the nanorods have single phase nature with wurtzite structure ...
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ZnO nanorods with diameter 90-100 nm range (tip diameter~15 nm) and length of about 2 μm have been prepared using microwave irradiation technique. X-ray diffraction (XRD) and transmission electron microscopy (TEM) results indicate that the nanorods have single phase nature with wurtzite structure and preferentially grow along [0001] direction. Raman spectrum shows the mode E2 high at 439 cm −1 that is related to the vibration of oxygen atoms in wurtzite ZnO. Room-temperature ultraviolet-visible (UV-vis) absorption spectrum shows the absorption band at around 399 nm (red-shifted as compared to bulk). This novel nanostructure would be a promising candidate for a variety of future applications.
Ratnika Varshneya; Seema Bhadauriaa; Mulayam S.Gaur
Abstract
This work reports a novel biological method for the synthesis of rod shaped silver nanoparticles by exploiting sundried Stevia rebaudiana leaves at ambient conditions. On treatment of aqueous solutions of silver with leaf powder, not only the rod shaped silver nanoparticles ranging from 80-200 nm diameter ...
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This work reports a novel biological method for the synthesis of rod shaped silver nanoparticles by exploiting sundried Stevia rebaudiana leaves at ambient conditions. On treatment of aqueous solutions of silver with leaf powder, not only the rod shaped silver nanoparticles ranging from 80-200 nm diameter and 400-800 nm height, but also cubes ranging from 55 to 80 nm in size, could be rapidly fabricated. The rate of reduction is much faster than those observed in earlier studies, highlighting the possibility that biological methodologies will achieve rates of synthesis comparable to those of chemical methods. The approach also appears to be a cost-efficient alternative to conventional methods, so it would be suitable for developing a biological process for large scale production. Instead of the boiled leaf broth used in previous studies, sundried leaf biomass could be preserved as an excellent bio-reductant, conveniently available any time for biosynthesis of the nanoparticles.
