College of Engineering, Pune

About: College of Engineering, Pune is a based out in . It is known for research contribution in the topics: Computer science & Sliding mode control. The organization has 4264 authors who have published 3492 publications receiving 19371 citations. The organization is also known as: COEP.

Chemical Recycling, Kinetics, and Thermodynamics of Hydrolysis of Poly(ethylene terephthalate) Waste with Nonaqueous Potassium Hydroxide Solution

Abstract: Poly(ethylene terephthalate) (PET) waste was reacted in a batch process with KOH in nonaqueous ehtylene glycol (EG) solution at 100–180°C for 5–140 min to convert them quantitatively into dipotassium terephthalate (K2-TPA) and EG. Particle size of PET, mol/L of KOH, and reaction time required for depolymerization of complete PET were optimized. Dipotassium terephthalate was precipitated into terephthalic acid (TPA) using HCl from the reaction mixture and separated readily. Other product EG, being the same component as nonaqueous solvent (EG) remains in liquid phase. The EG was recovered completely by using the salting-out method. Rate of hydrolysis was significantly accelerated by addition of another additional solvent, tetrahydrofurane (THF) to EG in the atmosphere of cyclohexylamine (CHA). Moreover, to improve the hydrolysis rate, TPA salt deposited from the unreacted PET surface was removed by introduction of dimethylsulfoxide (DMSO). Analyses of monomers (TPA and EG) and PET were undertaken. ...

The role of yield stress on cracked thin panels of aluminum alloys repaired with a fRP patch

Abstract: The aim of this study was to explore the effect of the yield stress of the cracked thin panels of aluminum alloys panel, repaired with one sided fiber reinforced polymer (FRP) patch, on the performance of the repair. Various different grades of aluminum alloys with thickness in the range of 1–1.3 mm were used as the skin material. The numerical simulation of the experimental results was done through ANSYS 15.0, using a cohesive zone material model (CZM model) at the interface of the skin and the patch. The effect of the far field applied stress was analyzed to simulate the initiation and the separation of the patch. In all the six cases, undertaken in this study, the patch separation occurred when the applied stress exceeded the yield stress of the skin by a small percentage. Even in the thinnest patch with its stiffness ratio of 0.28, the patch separated when the applied stress exceeded the yield strength of the skin material. In all the cases, the shear stress at the interface caused the slippag...

Decolorization of brilliant green dye using immersed lamp sonophotocatalytic reactor

Abstract: The textile and dye industries require an enormous amount of water for processing and produce a large volume of wastewater. Generated wastewater had potential hazards and a threat to the aquatic biota. The present work investigates the decolorization of brilliant green dye using a combination of two advanced oxidation techniques viz sonocatalysis and photocatalysis (immersed lamp) known as sonophotocatalysis (3 L capacity). The efficiency of decolorization is further improved in the presence of various additives viz. copper oxide, zinc oxide, and sodium chloride. The maximum decolorization of brilliant green (BG) (94.8% in 120 min) obtained in the presence of zinc oxide. The total organic carbon of the treated samples was measured to monitor complete mineralization of BG. The sonophotocatalytic process (in the presence of zinc oxide) shows maximum mineralization. Synergic combination of two oxidation processes increased the production of oxidizing radicals. Continuous cleaning of catalyst surface (due to sonolysis effect) improves the activity of the catalyst for photolysis operation. The present work is highly useful for the development of a sonophotocatalytic process.

High performance polyetherketone-hexagonal boron nitride nanocomposites for electronic applications

Abstract: High-performance polymeric nanocomposites have been increasingly demanded by many cutting-edge fields. In present work, high-performance polymeric nanocomposites based on polyetherketone polymer as a matrix and hexagonal boron nitride (h-BN) nanopowder as reinforcement were successfully fabricated using planetary ball milling followed by hot pressing. The effects of h-BN loading (0–30 wt%) on the thermal stability, linear coefficient of thermal expansion (CTE), Vickers microhardness, and storage modulus/loss modulus were systematically investigated and discussed. Scanning electron microscopy showed good dispersion of h-BN nanoparticles into the matrix. The thermal stability of the nanocomposites was found more than 560 °C which is higher than that of commercial epoxy/E-glass based substrate. The linear CTE of the 30 wt% h-BN nanocomposite decreased approximately 20% compared to that of pure matrix. The microhardness and storage modulus of the nanocomposites were found to increase approximately 38% and 70%, respectively. Moreover, the glass transition temperature of the nanocomposites was increased compared to that of pure matrix.

Optical numeral recognition algorithm for seven segment display

Abstract: The paper discusses an algorithm for the recognition of seven segment numbers on a display, so that the algorithm can be utilized for applications such as automated reading of LCD-based meters. The algorithm outlines a 7-step process consisting of four types of operations-Object Detection, Noise Removal, Image Segmentation and Numeral Recognition based on pixel density feature extraction. The performance of the algorithm is evaluated, by simulation and field tests, for robustness to variations of digit positions, brightness, contrast, tilt and noise. The recognition rate of the algorithm is 79% when tested over a wide range of variation in illumination and angular tilt conditions.