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Antireflection nanocomposite coating on PV panel to improve power at maximum power point
No full textA thorough investigation was performed on various chemicals and nanocomposite materials to apply antireflection coating on the PV panel intending to improve the solar cell efficiency by generating more voltage, current, and power at maximum power point (MPP). The improvement in solar cell efficiency would indicate the efficient way of utilizing solar energy and converting into electrical energy which in turn saves lot of cost and improves the power generation.To improve the efficiency by the coating approach, the nanocomposite materials mixing with some composition of efficient chemicals demonstrates
extremely encouraging change in surface inactivity, ntireflection, and wanted vitality band hole of the materials. After a detailed experimentation, it is been identified that the multiwall carbon nanotube, titanium dioxide, and silicon dioxide materials demonstrate elevated efficiency in increasing the VMPP, IMPP, and PMPP when compared with uncoated cells. The investigational inferences in detailed are analyzed along with scanning electron microscopy findings and finally characterized the poly-Si solar cell with coating. Overall, there is a relative improvement of 36.45% of efficiency when compared with the uncoated cells
Synthesis and characterization of thermally stable and flame retardant poly (benzoxazine-co�urethane) matrices
No full textABSTRACT
The flame-retardant behavior of organic polymers is considered as very important criteria to utilize them in the form of coatings, encapsulants, sealants, and matrices for high performance industrial applications. A new type of poly (benzoxazine-co-urethane) (PBZ-co-PU) matrices have been developed using dimethylol benzoxazine monomers (BZM and BZE) and tris(p-isocyanatophenyl) thiophosphate (Desmodur) through A2þ B3 approach followed by thermal curing. The molecular structure of developed PBZ-co-PU was confirmed by FT-IR spectra and their thermal stability and flame retardant behavior were studied by standard methods. Data obtained from TGA and DSC, indicate that the PBZ-co-PU possesses higher Tg, better thermal stability and LOI than those of neat PBZ. Further, it was also observed that among the two matrix systems (PBZ-co-PU-1 and PBZ-co-PU-2) studied, the PBZ-co-PU-1 based system exhibited higher Tg, thermal stability and flame retardant behavior than those of PBZ-co-PU-
Iron Oxide-Cobalt Nanocatalyst for O-tert-Boc Protection and O-Arylation of Phenols
No full textAbstract: Efficient and general protocols for the O-tert-boc protection and O-arylation of phenols were developed in this paper using a recyclable magnetic Fe3O4-Co3O4 nanocatalyst (Nano-Fe-Co), which is easily accessible via simple wet impregnation techniques in aqueous mediums from
inexpensive precursors. The results showed the catalysts were well characterized by XRD (X-ray Diffraction), ICP-AES (Inductive Coupled Plasma Atomic Emission Spectroscopy), TEM
(Transmission Electron Microscopy), TOF-SIMS (Time-Of-Flight Secondary Ion Mass Spectrometry) and XPS (X-ray Photoelectron Spectroscopy). The O-tert-boc protection and O-arylation of phenols was accomplished in good to excellent yields (85–95%) and the catalyst was reusable and recyclable
with no loss of catalytic activity for at least six repetitions
Evaluation of welding characteristics using three-dimensional finite element simulation and experimentation for FSW of aluminum 6061
No full textAim of this study is to introduce numerical 3D finite element method (FEM) simulation to study characteristics of friction
stir welding. A coupled experimental and numerical simulation study was carried out to study the effect of process
parameters on welding characteristics for friction stir welding of aluminium 6061. As per Box–Behnken design, 15
experiments have been conducted on aluminium 6061 plates at three levels of spindle speed, tilt angle and tool pin
diameter. Experimental results of tool vibration, force in X, Y and Z directions and ultimate tensile strength were collected
and analyzed. Shearing of metal and metal flow patterns during the welding were analyzed and the responses were
predicted using FEM simulation. Size of the shear zone around the tool pin was studied for different combinations of the
parameters. The experimental results and the FEM-simulated values were found to be in good agreement. Interaction effect
of the process parameters on the responses was analyzed using response surface methodolog
Study: wear and super hydrophobic behaviour of PTFE-ceria composite
No full textThe present work aims at developing a novel superhydrophobic polymer matrix composite with enhanced wear resistance. First, polytetrafluoroethylene (PTFE) matrices were reinforced with
different weight percentages (ranging from 0 to 20%) of ceria particles using the powder metallurgy method. Subsequently, the microtexture of the fabricated composites was varied
by sanding them with different grit sizes of emery sheets. The effect of reinforcement was analysed on tribological behaviour of fabricated composites via a pin-on-disk test.
Hydrophobic behaviour of textured PTFE and PTFE-20% ceria composite has been discussed. Surface topography and wear morphology of the polymer matrix composites were examined
with an aid of SEM. Tribological data revealed that lower friction coefficient and higher wear resistance can be achieved by increasing the weight percentage of ceria particles. A
maximum contact angle of 158° with a minimum roll-off angle of less than 3° was found for the PTFE-20% ceria composit
Efficiency monitoring as a strategy for cost effective maintenance of induction motors for minimizing carbon emission and energy consumption
No full textInduction motors are the major source of energy consumption in industries. Research work available on motor efficiency and energy consumption advocates the use of energy efficient motors to reduce the power consumption. However, these motors are also prone to faults which affects their operational efficiency. Over a period of time, the propagation of fault in the motor leads to the further drop in the efficiency which increases motor running loss. This loss is generally ignored by most of the researchers and managers and is a hidden cost borne by the industries. In this paper running of faulty induction motors and its associated financial losses have been addressed. It has been
assumed that for a motor running at constant load, fault propagation leads to further drop in its efficiency. Three
simulated scenarios: linear, exponential and quadratic drop in efficiency have been considered for estimation of
running loss. An algorithm has also been proposed for planning maintenance actions based on operational losses
due to faulty motor. This paper also highlights how efficiency and condition monitoring helps in reducing CO2 emissio
Non-enzymatic sensing of glucose using a screen-printed electrode modified with novel synthesized CeO2@ CuO core-shell nanostructure
No full textWe fabricated a fourth generation glucose biosensor using CeO2@CuO core shell nano structure (CeCCS NSs). A
simple leave extract of Ocimum tenuiflorum was used to prepare different wt% of 0.2, 04, 0.6, and 0.8 CuO (shell),
above 1 wt% of CeO2 (core). The successful formation was confirmed by various characterization techniques like
XRD, Uv–Vis, FTIR, SEM and HR-TEM. In the biosensor, 0.4 wt% of CeCCS NSs has shown efficient properties due to its high surface area. The good conductivity and high catalytic activity towards glucose sensing properties were estimated by screen-printed electrode (SPE). The ampherometric studies of CeCCS/SPE modified electrode have been optimized at potential + 0.4 V, showed a sensitivity of 3319.83 μAm M−1 cm−2 within detection limit of 0.019 μM. More significantly, modified electrodes performed excellently against anti-interference and antipoisoned activity in glucose sample and exhibited promising results for the sustainable improvement for nonenzymatic sensing applications
Structure and magnetic properties of Mn-Fe co-doped ZnO thin films deposited by Rfmagnetron sputtering
No full textt.Thin films of Mn-Fe co-doped ZnO deposited onto borosilicate glass substrates by rf-magnetron sputtering in argon gas pressure. The as deposited thin films show hexagonal wurtizite structure, without any secondary phases of Mn or Fe in host ZnO within XRD limit. The crystallite (D) of the films decreases with increase in argon working gas pressure. The field emission scanning electron microscope (FE-SEM) images show dense microstructure with increases in average grain size as a function of argon gas pressure are about ~ 12 – 44 nm. The elemental composition of the as eposited thin filmswere confirmed by EDS spectra. The room temperature M-H plots show clear signature of ferromagnetic behavior with increase working gas pressure, the magnetic moment (Ms) of as deposited thin films is about
32 to 47 emu/cc as a function of working gas pressure. The increase in ferromagnetism in Mn-Fe co-doped ZnO thin
films is due to coupled magnetic moments of multi atoms of Mn/Fe in host ZnO matrix
Optimum Wavelet-Based Homomorphic Medical Image Fusion Using Hybrid Genetic-Grey Wolf Optimization Algorithm
No full textMedical image fusion techniques have been widely
used in various clinical applications. Generalized homomorphic
filters have Fourier domain features of input image. In multi
modal medical image fusion discrete wavelet transform based
techniques provides more features and is performed over Fourier spectrum. In this paper, we proposed a Homomorphic wavelet fusion which is called Optimum Homomorphic Wavelet Fusion (OHWF) using Hybrid Genetic – Grey Wolf Optimization (HGGWO) Algorithm. In OHWF, which consist of logarithmic and
wavelet domain information of input images. The wavelet based
homomorphic fusion consists of multi level decomposition
features of input image. In our proposal, the approximation
coefficients of modality1 (anatomical structure) and optimum
scaled detailed coefficients of modality2 are given to adder1. In
adder 2, the optimum scaled detailed coefficients of modality 1
and approximation coefficients of modality 2 are added together. The resultants of adder 1 and adder 2 are fused together using pixel based averaging rule. Firstly, the proposed fusion approach is validated for MR-SPECT, MR-PET, MR-CT and MR T1-T2 image fusion using various fusion evaluation indexes. Later, the conventional grey wolf optimization is modified with genetic operator. Experimental results show that, the proposed approach outperforms state-of-the-art fusion algorithms in terms of both structural and the functional information in the fused image
Cardanol based benzoxazine blends and bio-silica reinforced composites: Thermal and dielectric properties
No full textIn the present work, a novel cardanol based benzoxazine was synthesised by reacting three different amines (Aniline (CrAb), N, N-dimethylaminopropylamine (CrDb) and caprolactam modified N, N-dimethylaminopropylamine (CrCb)) with cardanol in the
presence of formaldehyde at appropriate experimental conditions. The resulting benzoxazines were characterised for their molecular structure and thermal behaviour by
using different analytical methods. Among the different systems studied, the tertiary amine derivatives was found to reduce the curing temperature efficiently (CrAb-275 °C > CrDb265 °C > CrCb-251 °C) and are confirmed by DSC analysis. These cardanol based CrAb benzoxazine was blended with conventional benzoxazines (Bzs), bismaleimides (BMIs) as binary and ternary systems and studied their thermal properties. Three different catalysts (4-hydroxy acetophenone, 4-aminophenol, and 4-hydroxyphenyl maleimide) have been used to study the effect of lowering of curing temperature. Further, prepared benzoxazines
were reinforced with varying weight percentages (1, 3, 5 and 10 wt %) of bio-silica derived from rice husk to obtain hybrid composites. The dielectric studies of bio-silica reinforced
cardanol benzoxazines infer that the values of dielectric constant are decreased with increasing wt % of bio-silica. It was further observed that, 10 wt % of bio-silica reinforced
cardanol benzoxazines contributes to the lowest value of dielectric constant of 1.9 at 1MHz. From the data resulted from different studies, it is concluded that the blends of cardanol
based benzoxazines can be used in the form of sealants, encapsulants, adhesives and matrices in the fields of microelectronics and automobile applications for better
performanc