In this work, an attempt is made to find out the difference in erosion resistance of bidirectional (fibre orientation in 0° and 90° only) and multidirectional (fibre orientation in 0°, 15° 30°, 45°, ...60°, 75°, and 90°) glass fibre epoxy composites. The erosion rate of the composites at different sand impingement angles (30°, 45°, 60°, and 90°) and at different velocities (86.57m/s, 101.15m/s, and 119.2m/s) was observed. The maximum erosion rate was observed at 45° sand impingement angle for both bidirectional and multidirectional composites. The orientation of the fibre in the composite has very little significance on the erosion rate. Both the composites with unidirectional and bidirectional glass fibre showed semi ductile behaviour. SEM was used to examine the surface of the specimen subjected to erosion. Erosion tendency with impact angle and fibre orientation was also touched upon in the study.
This paper deals with the manufacture and examination of tribological properties of epoxy composites reinforced with graphitic carbon nitride (g-C3N4) nanopowder. The composites had prepared with ...five different proportions of g-C3N4 nanopowder using a hand layup process. Comparison of tribological properties has made between the composites laid at different percentages of g-C3N4 in epoxy. The results showed the maximum erosion resistance of g-C3N4 particulate polymer matrix for 3% filler content. Also, by Scanning Electron Microscope (SEM), the erosion morphology analysis is done on the internal structures of the specimen.
Customized properties can be attained for composite materials by varying the percentage of matrix and reinforcement materials and also by laying out the reinforcement in different orientations in the ...matrix. The present work aims to evaluate the mechanical properties of bi-directional (all layers at 0° and 90°) and multi-directional (laid at 0°, 15°, 30°, 45°, 60°, 75° and 90°) woven glass fibre reinforced epoxy composites. The composites were prepared by the hand-lay-up method. The tensile and flexural strengths of the composites were studied as per ASTM standards. The maximum tensile and flexural strengths of 193 MPa and 232 Mpa respectively were attained for composites with bi-directional fibres containing 12 layers. The mechanism of failure for the tested samples was investigated by a scanning electron microscope and the results are reported.
During the process development of montelukast sodium, three polar impurities and one non-polar impurity with respect to montelukast sodium were detected by simple reverse phase high-performance ...liquid chromatography (HPLC). Initially, all the four impurities were identified by the liquid chromatography–mass spectrometry (LC–MS) data and out of four impurities, three have been prepared by the synthetic method and remaining one is isolated by preparative HPLC. Based on the spectral data (IR,
1H NMR,
13C NMR and MS), the structure of these impurities 1–4 were characterised as 1-(1
R)-1-3-(1
E)-2-(7-chloro-2-quinolinyl)ethenylphenyl-3-2-(1-hydroxy-1-methylethyl)phenylpropylthiomethylcyclopropane acetamide (impurity-1), {1-1-{3-2-(7-chloro-quinolin-2-yl)-vinyl-phenyl}-3-(2-isopropenyl-phenyl)-propylsulfanylmethyl-cyclopropyl}-acetic acid (impurity-2), 1-(1
R)-1-3-(1
E)-2-(7-chloro-2-quinolinyl)ethylphenyl-3-2-(1-hydroxy-1-methylethyl)phenylpropylthiomethylcyclopropaneacetic acid (impurity-3) and 1-(1
R)-1-3-(1
E)-2-(2-quinolinyl)ethenylphenyl-3-2-(1-hydroxy-1-methylethyl)phenylpropylthiomethylcyclopropaneacetic acid (impurity-4).
In the present study, electrical discharge machining(EDM) studies are carried out on sillimanite reinforced Aluminium based composite. The composite is prepared through vacuum stir casting setup. EDM ...studies are carried out in the prepared specimen by considering input parameters such as current flow, pulse on time, pulse off time and voltage. After machining the cylindricity is measured using CMM and the influence of the input parameters on cylindricity and material removal rate(MRR) is determined. The result shows that the addition of sillimanite drastically reduces the machinability of the composite under all operating conditions. Cylindricity of the material increased with the rise in current flow.
Twenty-two typical pedons (14 soil series- TTK1 to TTK-14) representing major landforms of Tatrakallu village of Ananatapuramu district of Andhra Pradesh were evaluated by using qualitative and ...quantitative methods. Three major land capability classes (III, IV and VI) were identified with two sub classes (erosion and wetness). Crop suitability analysis revealed that the village falls under marginally suitable (S3) with limitations of soil fertility, wetness and sodicity and not suitable (N) with limitations of slope, texture shallow rooting depth, sodicity and poor nutrient status. Riquier’s parametric approach was found to be good indicator for identification of production potential. The land evaluation revealed that, suitability and productivity of these soils were highly variable, and hence their management must be site-specific. The suggestion including the crop residue retention, nutrient recycling, minimum tillage, crop rotation, cover crops and intercropping not only helps to conserve soil and water more effectively in soils but also increase organic matter content and improve fertilizer use efficiency. Farmers continued to grow groundnut, pigeonpea, chickpea and castor for many years on marginally suitable as they are not aware of suitable soils for a particular crop. Adoption of suggested ameliorative measures and land use not only improve the yield but also sustain the soil productivity.
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