Browsing by Author "Patil, S.S."

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A Development of Micropump Based on Cooling System for Laptops
(Springer Science and Business Media Deutschland GmbH, 2024) Patil, S.S.; Mohith, S.; Karanth P, P.; Kulkarni, S.M.
This paper aims to study a new mechanical diaphragm micropump for a liquid cooling system for laptops. A low weight, high discharge diaphragm pump has been developed successfully to pump the coolant by the crank and extended rocker mechanism using a micro gear dc motor. The bossed diaphragm pump chamber and mechanism are fabricated using high-quality PLA with optimized parameters and the FDM 3D printing method. Both valves and diaphragm are created using silicon rubber. The reciprocating action of the mechanism develops the suction and discharge stages that make the pump work. The pumpâ€™s performance is analyzed using an experimental setup that has been developed and implemented. The diaphragm design, pump chamber, operating voltage, and coolant type all affect the performance of a bossed diaphragm pump driven by a crank and extended rocker mechanism. The measured maximum flow rate of the designed prototype is 94Â mL/min for water and 65Â mL/min for ethylene glycol solution within 5Â V actuation voltage and zero pressure head. Â© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.
A Negative Effect of Niobium-Doped Ceria on Soot Oxidation Activity‡
(John Wiley and Sons Inc, 2022) Patil, S.S.; Naik, S.; Ramesh, M.D.; Harshini, H.; Prasad Dasari, H.P.
Niobium-doped ceria catalysts were synthesized to study soot oxidation activity. X-Ray diffraction (XRD) and Raman analysis of the samples revealed the presence of a fluorite structure of CeO2 for all the doped samples. The T50 temperature of the pure CeO2 sample was more significant than that of bare soot. The high catalytic activity of the CeO2 catalyst can be attributed to the low crystallite size, high facet ratio, and the large Brunauer-Emmett-Teller (BET) surface area as compared to Nb-doped samples. The activation energy calculated by both Ozawa and KAS methods were found to be low for CeO2 when compared to Nb-doped samples. CeO2 resulted in better soot oxidation activity with low activation energy. © 2022 Wiley-VCH GmbH
An investigation on copper-loaded ceria-praseodymium catalysts for soot oxidation activity and its kinetics
(Springer Science and Business Media Deutschland GmbH, 2024) Patil, S.S.; Prasad Dasari, H.P.
The Cu-loaded Ce-Pr catalyst series was successfully developed to study their performance on soot oxidation activity and its kinetic behavior. The doped samples showed a similar trend for cubic fluorite structure except for CuO, which possessed a monoclinic structure from the XRD analysis. Facet ratios [{100}/{111} and {110}/{111}] for the reactive planes were calculated from XRD spectra; the ratio was high for the 5 Cu-CP catalysts. The oxygen vacancy peaks were noticed from Raman spectra for the doped samples. 5 Cu-CP displayed the better catalytic activity of T50 = 402 °C, which may be attributed to high reactive planes and better reducibility. The addition of Cu showed a slight enhancement in catalytic activity compared to CP and pure Ce. The kinetic triplets were evaluated: the activation energy (Ea), pre-exponential factor (A), and the reaction model. Pure Ce displayed the lowest Ea and A values, whereas pure Cu showed high Ea and A values by all the methods. Graphical abstract: (Figure presented.) © The Author(s) under exclusive licence to Associação Brasileira de Engenharia Química 2023.
Analytical solutions using a higher order refined computational model with 12 degrees of freedom for the free vibration analysis of antisymmetric angle-ply plates
(2008) Swaminathan, K.; Patil, S.S.
Analytical formulations and solutions to the natural frequency analysis of simply supported antisymmetric angle-ply composite and sandwich plates hitherto not reported in the literature based on a higher order refined computational model with 12 degrees of freedom already reported in the literature are presented. The theoretical model presented herein incorporates laminate deformations which account for the effects of transverse shear deformation, transverse normal strain/stress and a nonlinear variation of in-plane displacements with respect to the thickness coordinate thus modelling the warping of transverse cross sections more accurately and eliminating the need for shear correction coefficients. In addition, another higher order computational model with five degrees of freedom already available in the literature is also considered for comparison. The equations of motion are obtained using Hamilton's principle. Solutions are obtained in closed-form using Navier's technique by solving the eigenvalue equation. Plates with varying slenderness ratios, number of layers, degrees of anisotropy, edge ratios and thickness of core to thickness of face sheet ratios are considered for analysis. Numerical results with real properties using above two computational models are presented and compared for the free vibration analysis of multilayer antisymmetric angle-ply composite and sandwich plates, which will serve as a benchmark for future investigations. 2007 Elsevier Ltd. All rights reserved.
Analytical solutions using a higher order refined computational model with 12 degrees of freedom for the free vibration analysis of antisymmetric angle-ply plates
(2008) Swaminathan, K.; Patil, S.S.
Analytical formulations and solutions to the natural frequency analysis of simply supported antisymmetric angle-ply composite and sandwich plates hitherto not reported in the literature based on a higher order refined computational model with 12 degrees of freedom already reported in the literature are presented. The theoretical model presented herein incorporates laminate deformations which account for the effects of transverse shear deformation, transverse normal strain/stress and a nonlinear variation of in-plane displacements with respect to the thickness coordinate thus modelling the warping of transverse cross sections more accurately and eliminating the need for shear correction coefficients. In addition, another higher order computational model with five degrees of freedom already available in the literature is also considered for comparison. The equations of motion are obtained using Hamilton's principle. Solutions are obtained in closed-form using Navier's technique by solving the eigenvalue equation. Plates with varying slenderness ratios, number of layers, degrees of anisotropy, edge ratios and thickness of core to thickness of face sheet ratios are considered for analysis. Numerical results with real properties using above two computational models are presented and compared for the free vibration analysis of multilayer antisymmetric angle-ply composite and sandwich plates, which will serve as a benchmark for future investigations. © 2007 Elsevier Ltd. All rights reserved.
Bending of sandwich plates with anti-symmetric angle-ply face sheets - Analytical evaluation of higher order refined computational models
(2006) Swaminathan, K.; Patil, S.S.; Nataraja, M.S.; Mahabaleswara, K.S.
The aim of the present study is to assess the accuracy of the few computational models based on various shear deformation theories in predicting the bending behaviour of sandwich plates with anti-symmetric angle-ply face sheets under static loading. Five two-dimensional models available in the literature are used for the present evaluation. The performance of the various models is evaluated on a simply supported laminated plate under sinusoidal loading. The equations of equilibrium are derived using the principle of minimum potential energy (PMPE). Analytical solution method using double Fourier series approach is used in conjunction with the admissible boundary conditions. The accuracy of each model is established by comparing the results of composite plates with the exact solutions already available in the literature. After establishing the correctness of the theoretical formulations and the solution method, benchmark results for transverse displacement, in-plane stresses, moment and shear stress resultants are presented for the multilayer sandwich plates. 2006 Elsevier Ltd. All rights reserved.
Bending of sandwich plates with anti-symmetric angle-ply face sheets - Analytical evaluation of higher order refined computational models
(2006) Swaminathan, K.; Patil, S.S.; Nataraja, M.S.; Mahabaleswara, K.S.
The aim of the present study is to assess the accuracy of the few computational models based on various shear deformation theories in predicting the bending behaviour of sandwich plates with anti-symmetric angle-ply face sheets under static loading. Five two-dimensional models available in the literature are used for the present evaluation. The performance of the various models is evaluated on a simply supported laminated plate under sinusoidal loading. The equations of equilibrium are derived using the principle of minimum potential energy (PMPE). Analytical solution method using double Fourier series approach is used in conjunction with the admissible boundary conditions. The accuracy of each model is established by comparing the results of composite plates with the exact solutions already available in the literature. After establishing the correctness of the theoretical formulations and the solution method, benchmark results for transverse displacement, in-plane stresses, moment and shear stress resultants are presented for the multilayer sandwich plates. © 2006 Elsevier Ltd. All rights reserved.
Ceria-based electrospun nanofibers and their widespread applications: A review
(Academic Press, 2025) Prasad Dasari, H.P.; Patil, S.S.; Kamath, R.S.; Kisiela-Czajka, A.M.
Electrospinning is a highly efficient technique for producing nanofibers, and it is noted for its cost-effectiveness, versatility, and user-friendly nature. The article evaluates the production of Ceria-based nanofibers primarily utilizing electrospinning technology and electrospinning parameters and explores their various potential applications. Ceria infused with lanthanoids and transition metals demonstrates significant potential as catalysts, optical sensors, and supercapacitors in various energy-related industrial applications. Their role as catalysts in water-gas and reverse water-gas shift reactions greatly enhances the water-splitting reaction in the Deacon process. Composite ceria nanofibers for wound therapy were developed by integrating polyurethane, cellulose acetate, and zein for biological applications. Soot-induced blockages in automobile filters pose challenges for the regeneration process of diesel particle filters, and the effectiveness of ceria-based nanofibers in soot and CO oxidation has been explored. Ce-based nanofibers produced via the electrospinning technique, with different operating parameters, exhibit notable variations in their morphology. Research indicates that, compared to traditional ceria, Ce-based nanofibers demonstrate greater surface area and porosity, a higher density of oxygen vacancies, and improved oxygen transfer efficiency, all essential for numerous redox and catalytic processes. The nanofibrous structure enhances electrical conductivity by expanding the surface area accessible for interaction with active components. The nanofibrous composite structure exhibits enhanced thermal and mechanical durability, making it appealing for numerous applications. © 2025 Elsevier Ltd
Ceria-Terbium-based electrospun nanofiber catalysts for soot oxidation activity and its kinetics
(Taiwan Institute of Chemical Engineers, 2024) Patil, S.S.; Kumar, R.; Prasad Dasari, H.P.
Background: Ceria-based materials have an excellent potential to be catalysts for catalytic three-way converters in the automobile industry. Developing Ceria-based nanofiber catalysts can be a significant approach for further exploring the application of these materials in automobile industries. Methods: In this study, Ag, Cu, or Co doped Ceria–Terbium nanofibers were synthesized using the electrospinning technique. The obtained nanofiber catalysts were characterized using FE-SEM, XRD, FT-Raman Spectroscopy, and BET-BJH analysis and tested for soot oxidation activity and its kinetics. Significant findings: FE-SEM examination reveals that the obtained nanofibers have a diameter ranging from around 100 to 600 nm. CeTbCo nanofibers exhibited a reduced particle size and enhanced pore formation. The XRD investigation revealed that all the nanofibers displayed a face-centered fluorite structure of CeO2. In Raman spectroscopy analysis, CeTbCo nanofibes showed the emergence of a secondary Co3O4 phase. The CeTbCo nanofiber catalyst showed better SBET (specific surface area) (66 m2/g) and average pore size (12.08 nm) and total pore volume (0.223 cc/g)), better soot oxidation activity (T50 = 347 ℃) than other nanofiber catalysts. The CeTbCo nanofiber catalyst exhibited an activation energy of 132 kJ mol−1 and a pre-exponential factor (ln (A)) of 25.63 min−1. © 2024 Taiwan Institute of Chemical Engineers
Diesel soot oxidation over Mn–Pr–Ce oxide catalysts: structural changes and the impact of Mn doping
(Royal Society of Chemistry, 2025) Patil, S.S.; Prasad Dasari, H.P.; Shirasangi, R.; Harshini, H.
The soot oxidation activity of manganese-doped ceria-praseodymium catalysts, synthesized via solution combustion synthesis, was evaluated. The analyses performed with XRD and Raman spectroscopy indicated that the Mn-doped CP catalysts displayed the typical fluorite structure of CeO2. The addition of Mn to CP led to a reduction in crystallite size from 14 nm to below 10 nm. The F2g Raman active mode of fluorite-structured Ce and the oxygen vacancies resulting from the addition of Mn and Pr (bands B 560 cm–1 to 580 cm–1) were consistently observed across all Mn-doped CP catalysts. 15 and 20 Mn-CP exhibited an additional secondary phase identified as Mn2O3. The analysis of BET surface area and BJH pore size revealed that the Mn-doped CP catalysts exhibited both micro and mesoporous characteristics. The H2-TPR and O2-TPD profiles indicated enhanced reducibility resulting from the incorporation of Mn and Pr into CeO2-doped catalysts. The improved T50 (365 ± 1 1C) for the 5 Mn-CP catalytic system is primarily due to its increased specific surface area of 45 m2 g–1 and the presence of active surface adsorbed oxygen species identified in the XPS and O2-TPD studies. 5 Mn-CP exhibited the lowest activation energy value compared to all other Mn-doped catalysts. © 2025 The Author(s)
Effect of Ag loading on praseodymium doped ceria catalyst for soot oxidation activity
(Springer, 2022) Govardhan, P.; Anjana, A.P.; Patil, S.S.; Prasad Dasari, H.P.; Harshini, H.; Shourya, A.
Silver-loaded praseodymium doped ceria (XAg/PDC) was synthesized by microwave-assisted co-precipitation and wetness impregnation. XRD confirms the fluorite structure of ceria without secondary phase, and Raman spectroscopy represents the increased generation of oxygen vacancies with Ag loading. The TEM analysis shows lattice fringes corresponding to both CeO2 and Ag on the surface. The BET and BJH analysis of catalyst confirms the high porosity accompanied by high surface area and pore diameter of 5Ag/PDC and 15Ag/PDC, making it more active for the oxidation reaction. From the XPS analysis the amount of surface Ce3+ concentration and the surface chemisorbed oxygen species (O2 2) is high for 5Ag/PDC and 15Ag/PDC, in line with XRD and Raman results. The soot oxidation T50 temperature follows the trend: 5Ag/PDC∼15Ag/PDC<10Ag/PDC<20Ag/PDC<0Ag/PDC. The Ag loading increased the surface reducibility of cerium ions and thus 5 wt% was optimized. © 2021, The Korean Institute of Chemical Engineers.
Effect of fuel and solvent on soot oxidation activity of ceria nanoparticles synthesized by solution combustion method
(KeAi Communications Co., 2019) Patil, S.S.; Prasad Dasari, H.P.
Effect of fuel (glycine and urea) and solvent (water, acetone and ethanol) on the soot oxidation activity of ceria nanoparticles synthesized by solution combustion method is carried out in the present study. X-ray diffraction (XRD) patterns displayed a fluorite structure and the Tauc's plot obtained from UV-Diffusive Reflectance spectroscopy (UV-DRS) showed that the band gap value was around 2.9–3.1 eV for the synthesized ceria nanoparticles irrespective of the fuel and solvent used. Ceria nanoparticles synthesized using glycine and acetone resulted in lower crystallite size, higher facet ratios ([1 0 0]/[1 1 1] and [1 1 0]/[1 1 1]) and higher lattice strain than compared to other solvents and fuels and thus resulted in better soot oxidation activity (T50 = 416 °C). The present synthesis method has played a significant role in improving the reactive facet ratios, providing lower crystallite size and high lattice strain. © 2019
Effect of morphology and oxidation state of nickel on diesel soot oxidation activity
(Elsevier Ltd, 2022) Vijay, M.P.A.; Patil, S.S.; Madhura, D.R.; Anjana, A.P.; Gouramma, P.; Prasad Dasari, H.P.; Arya, S.B.; Harshini, H.
NiO sample is synthesized using the EDTA citrate complex method and calcined at 600 °C/5 h. Ni sample was acquired by reducing NiO to Ni at 600 °C in 4% H2/N2 atmosphere. Its physicochemical properties were obtained by XRD and Raman spectroscopy analysis, where it confirmed the complete reduction of NiO to Ni. SEM and TEM micrographs revealed a drastic particle growth for the Ni, indicating NiO sintering during the reduction process and a considerable surface morphology change. Ozawa and KAS methods were used to calculate the mean activation energy (Ea) value. NiO displayed lower Ea than Ni. Hence, NiO showed better catalytic activity than Ni. © 2022
Effect of Nd-doping on soot oxidation activity of Ceria-based nanoparticles synthesized by Glycine Nitrate Process
(2019) Patil, S.S.; Dasari, Hari Prasad; Dasari, H.; Dasari, H.
Neodymium-doped Ceria (NDC, Nd = 0, 1, 3, 5, 10, 20 and 30 mol %) catalysts were successfully synthesized by Glycine-Nitrate-Process (GNP) and tested for soot oxidation activity. For all NDC catalysts, XRD and Raman spectroscopy analyses showed a fluorite structure of ceria having an F2gRaman active symmetric breathing mode (O-Ce-O). 1NDC catalyst displayed better T50 temperature (427?C) followed by 0NDC (435?C), and 30NDC showed the highest T50 temperature (460?C). From XPS analysis, 1NDC and 0NDC catalysts showed a high amount of Ce3+ concentration and the surface-active oxygen species than compared to other NDC catalysts and thus, resulted in better soot oxidation activity indicating that the surface Ce3+ concentration and surface-active oxygen species play a key descriptor role in tuning the soot oxidation activity of NDC catalysts. 2019 Elsevier B.V.
Effect of Nd-doping on soot oxidation activity of Ceria-based nanoparticles synthesized by Glycine Nitrate Process
(Elsevier B.V., 2019) Patil, S.S.; Prasad Dasari, H.P.; Harshini, H.
Neodymium-doped Ceria (NDC, Nd = 0, 1, 3, 5, 10, 20 and 30 mol %) catalysts were successfully synthesized by Glycine-Nitrate-Process (GNP) and tested for soot oxidation activity. For all NDC catalysts, XRD and Raman spectroscopy analyses showed a fluorite structure of ceria having an F2gRaman active symmetric breathing mode (O-Ce-O). 1NDC catalyst displayed better T50 temperature (427?C) followed by 0NDC (435?C), and 30NDC showed the highest T50 temperature (460?C). From XPS analysis, 1NDC and 0NDC catalysts showed a high amount of Ce3+ concentration and the surface-active oxygen species than compared to other NDC catalysts and thus, resulted in better soot oxidation activity indicating that the surface Ce3+ concentration and surface-active oxygen species play a key descriptor role in tuning the soot oxidation activity of NDC catalysts. © 2019 Elsevier B.V.
From non-renewable waste to activated carbon: A smart move towards sustainable development and environmental protection in a circular economy
(Elsevier Ltd, 2025) Patil, S.S.; Kisiela-Czajka, A.M.; Prasad Dasari, H.P.
Waste generation is unavoidable as the population grows and globalisation/modernisation occurs. Ineffective garbage management and treatment raise major environmental concerns. This study provides a comprehensive and unique compilation of available knowledge on the potential use of various non-renewable waste materials to produce activated carbon (AC). One document brings together and evaluates the potential for converting hazardous and non-hazardous waste – from industrial and municipal to recyclable and medical waste – into a valuable resource with wide-ranging applications. The appropriately selected conversion method is key to converting waste into a valuable activated carbon product. It must consider both the applicable legal regulations and the key technological parameters that determine the quality and suitability of the final product for a specific application. The numerous carbonisation and activation methods employed to convert waste to AC include hydrothermal, ionothermal, pyrolysis and microwave-assisted methods. AC's elemental composition and functional groups are analysed using elemental analysis, XPS and FTIR. Crystal structure and phase identification are performed via XRD, SEM and TEM. Surface area and porosity are determined using the BET and BJH methods, along with the iodine index. Following the thermal conversion of various waste materials into AC, it is widely used in multiple disciplines, including energy and the environment. AC is used as an adsorbent to effectively remove harmful elements from water, including pharmaceutical contamination, dyes and heavy metals. AC has excellent electrochemical characteristics and is highly efficient in CO2 capture. AC also extracts valuable products such as hydrocarbons, methane and uranium. © 2025 The Author(s)
Higher order refined computational model with 12 degrees of freedom for the stress analysis of antisymmetric angle-ply plates - analytical solutions
(2007) Swaminathan, K.; Patil, S.S.
Analytical formulations and solutions for the stress analysis of simply supported antisymmetric angle-ply composite and sandwich plates hitherto not reported in the literature based on a higher order refined computational model with twelve degrees of freedom already reported in the literature are presented. The theoretical model presented herein incorporates laminate deformations which account for the effects of transverse shear deformation, transverse normal strain/stress and a nonlinear variation of in-plane displacements with respect to the thickness coordinate thus modelling the warping of transverse cross sections more accurately and eliminating the need for shear correction coefficients. In addition, two higher order computational models, one with nine and the other with five degrees of freedom already available in the literature are also considered for comparison. The equations of equilibrium are obtained using Principle of Minimum Potential Energy (PMPE). Solutions are obtained in closed form using Navier's technique by solving the boundary value problem. Accuracy of the theoretical formulations and the solution method is first ascertained by comparing the results with that already available in the literature. After establishing the accuracy of the solutions, numerical results with real properties using all the computational models are presented for the stress analysis of multilayer antisymmetric angle-ply composite and sandwich plates, which will serve as a benchmark for future investigations. 2006.
Higher order refined computational model with 12 degrees of freedom for the stress analysis of antisymmetric angle-ply plates - analytical solutions
(2007) Swaminathan, K.; Patil, S.S.
Analytical formulations and solutions for the stress analysis of simply supported antisymmetric angle-ply composite and sandwich plates hitherto not reported in the literature based on a higher order refined computational model with twelve degrees of freedom already reported in the literature are presented. The theoretical model presented herein incorporates laminate deformations which account for the effects of transverse shear deformation, transverse normal strain/stress and a nonlinear variation of in-plane displacements with respect to the thickness coordinate thus modelling the warping of transverse cross sections more accurately and eliminating the need for shear correction coefficients. In addition, two higher order computational models, one with nine and the other with five degrees of freedom already available in the literature are also considered for comparison. The equations of equilibrium are obtained using Principle of Minimum Potential Energy (PMPE). Solutions are obtained in closed form using Navier's technique by solving the boundary value problem. Accuracy of the theoretical formulations and the solution method is first ascertained by comparing the results with that already available in the literature. After establishing the accuracy of the solutions, numerical results with real properties using all the computational models are presented for the stress analysis of multilayer antisymmetric angle-ply composite and sandwich plates, which will serve as a benchmark for future investigations. © 2006.
Higher order refined computational models for the free vibration analysis of antisymmetric angle ply plates
(2008) Swaminathan, K.; Patil, S.S.
Analytical formulations using two higher order refined displacement models have been developed and solutions presented for the first time to the natural frequency analysis of antisymmetric angle-ply composite and sandwich plates. These computational models already reported in the literature are based on Taylor's series expansion of the displacements in the thickness coordinate and consider the realistic parabolic distribution of transverse shear strains through the laminate thickness. One of them, with 12 degrees of freedom, considers the effects of both transverse shear and normal strain/stress while the other with 9 degrees of freedom includes only the effect of transverse shear deformation. In addition to above, a few higher order models and the first order model developed by other investigators and available in the literature are also considered for the evaluation. A simply supported plate is considered throughout as a test problem. The equations of motion are obtained using Hamilton's principle. Solutions are obtained in closed form using Navier's technique by solving the eigenvalue equation. Plates with varying slenderness ratios, number of layers, fiber orientations, degrees of anisotropy, edge ratios and thickness of core to thickness of face sheet ratios are considered for the analysis. Accuracy of the theoretical formulations and the solution method is first ascertained by comparing the results with those already available in the literature. After establishing the accuracy of the solutions, extensive numerical results are presented for the free vibration analysis of multilayer antisymmetric angle-ply composite and sandwich plates using all the models, which will serve as a benchmark for future investigations. SAGE Publications 2008.
Higher order refined computational models for the free vibration analysis of antisymmetric angle ply plates
(2008) Swaminathan, K.; Patil, S.S.
Analytical formulations using two higher order refined displacement models have been developed and solutions presented for the first time to the natural frequency analysis of antisymmetric angle-ply composite and sandwich plates. These computational models already reported in the literature are based on Taylor's series expansion of the displacements in the thickness coordinate and consider the realistic parabolic distribution of transverse shear strains through the laminate thickness. One of them, with 12 degrees of freedom, considers the effects of both transverse shear and normal strain/stress while the other with 9 degrees of freedom includes only the effect of transverse shear deformation. In addition to above, a few higher order models and the first order model developed by other investigators and available in the literature are also considered for the evaluation. A simply supported plate is considered throughout as a test problem. The equations of motion are obtained using Hamilton's principle. Solutions are obtained in closed form using Navier's technique by solving the eigenvalue equation. Plates with varying slenderness ratios, number of layers, fiber orientations, degrees of anisotropy, edge ratios and thickness of core to thickness of face sheet ratios are considered for the analysis. Accuracy of the theoretical formulations and the solution method is first ascertained by comparing the results with those already available in the literature. After establishing the accuracy of the solutions, extensive numerical results are presented for the free vibration analysis of multilayer antisymmetric angle-ply composite and sandwich plates using all the models, which will serve as a benchmark for future investigations. © SAGE Publications 2008.