Faculty Publications
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Item Green Synthesis of Nanomaterials(Elsevier, 2018) Devatha, C.P.; Thalla, A.K.The nanotechnology industry is increasingly promoting nano as a “green” technology that will improve the environmental performance of existing industries, reduce consumption of resources and energy, and allow achievement of environmentally benign economic expansion. Eco-friendly solutions are gaining popularity in the contemporary world. A green method for nanoparticle synthesis should be assessed considering three aspects: the solvent, the capping agent, and the reducing agent compared to physical and chemical methods. Particularly, the plant extracts mediated process is a good and advantageous method for the development of metal nanoparticles compared to using microorganisms, in which the cell maintenance time is limited. Synthesis and characterization of nanoparticles are important steps to be adopted to apply nanoparticles in field applications, and these steps include preparation of leaf extract, Phytochemical screening, and preparation of precursor. Various factors affecting the synthesis of nanoparticles, such as pH, temperature, and time, will be discussed. The degradation of any organic compounds by the green approach (plant extracts) is mainly due to the presence of polyphenols in the biodegradable material. Although the synthesis of nanoparticles has been trending higher, their application in the area of waste water treatment has been limited until recently. Hence, the application of nanoparticles to waste water treatment will be discussed with a view toward paving the way for an alternate source of water. © 2018 Elsevier Ltd. All rights reserved.Item Ba-ZnO nanoparticles for photo-catalytic degradation of chloramphenicol(American Institute of Physics Inc. subs@aip.org, 2018) Kulkarni, R.M.; Malladi, R.S.; Hanagadakar, M.S.; Shetti, N.P.; Doddamani, M.Pristine ZnO (PZO) and 5% barium doped ZnO nanoparticles (BZONP) were prepared by in expensive chemical precipitation method. The techniques used to characterize prepared nanoparticles are X-ray powder diffraction (XRD), Energy Dispersive X-ray Spectroscopy (EDX), Scanning Electron Microscope (SEM), UV-visible absorption spectroscopy and Transmission Electron Microscope (TEM) analysis. The particle size of PZO and BZONP were calculated using Scherrer equation. The photo-catalytic efficiency of 5% BZONP was studied with photo-degradation of chloramphenicol (CLP) under UVC (254 nm) irradiation in aqueous suspension. Pseudo-first order rate constants (kobs) were found to increase with the decrease in pH. The effect of initial concentration, photo-catalyst loading, light intensity, the effect of pH on the photo-degradation rate was also examined and elaborately discussed. The results showed that BZONP is a better photo-catalyst compared PZO. The HPLC and LC/MS were used to identify photo-degradation products. © 2018 Author(s).Item The potential of nanoparticle additives in biodiesel: A fundamental outset(American Institute of Physics Inc. subs@aip.org, 2020) Soudagar, M.E.M.; Ghazali, N.-N.; Akram, N.; Al-Rashid, M.A.; Badruddin, I.A.; Khan, H.; Kallannavar, V.; Shahpurkar, K.; Afzal, A.; Farade, R.; Taqui, S.N.; Ukkund, S.J.Biodiesel is an unparalleled alternative fuel source envisioned to encompass the significance of diesel fuel and reduce greenhouse gas emissions because to its locked carbon cycle. However, it increases the nitrogen oxide emission, regular engine parts replacement due to clogging, and is not suitable in cold weather conditions. The addition of nanoparticles (metallic, non-metallic, oxygenated, organic and amalgamation) with diesel-biodiesel emulsion fuels results in an enhancement in the engine performance, thermo-physical properties, enrichment in the heat transfer rate, the equilibrium of the fuel mixtures and drop in the exhaust emissions reliant on the prescription of nanoparticle additives. The review intends to demonstrate the most recent nanoparticle additives used in diesel-biodiesel fuels. © 2020 Author(s).Item Preparation of functionalized graphene-linear low-density polyethylene composites by melt mixing method(American Institute of Physics Inc. subs@aip.org, 2020) Chavan, S.; Gumtapure, V.; Arumuga Perumal, D.A.Graphene is attracting gigantic amount of scientific interest due to its excellent thermo-physical properties. Graphene integration improves the electrical and mechanical properties of polyethylene-based polymers. This paper is concerned with the comprehensive procedure of preparing, morphological characterization and thermal property evaluation of nanoparticle blended polymer composites. Polymer composites are intended to consecrate the thermal energy storage applications. Linear low-density polyethylene (LLDPE) is incorporated with functionalized graphene with different concentrations (1, 3 and 5%). The morphological study revealed compatibility of polymer composites, at lower concentrations (1-3%) it shows homogenous dispersion, but above threshold limit the particle distribution is non-homogenous with coarse surface structures. Higher concentration (5%) of nanoparticles emulsifies the molecules and generates micelles between themselves. The thermal conductivity of the polymer composite is significantly enhanced with the reduction of specific heat. At lower concentrations polymer exhibits homogeneous dispersion and the interfacial interaction is comparatively higher, optimal concentration (3%) of nanoparticle provides favorable results and hence polymer composites with ideal concentration can be utilized for thermal energy storage applications. © 2020 Author(s).Item Three-Dimensional FEM Analysis of Nanoparticle-Assisted Radiofrequency Ablation of Tissue-Mimicking Phantom(Springer Science and Business Media Deutschland GmbH, 2021) Naik, S.S.; Bonthala, B.P.; Yadav, A.K.Radiofrequency ablation (RFA) is a minimally invasive procedure to damage the cancer cells. In RFA, heat is generated only at the center zone of the tumor, and this heat has to propagate up to the periphery of the tumor. Since the thermal conductivity of phantom is low, it reduces heat transfer rate, and time required for complete ablation of tumor will be more. Since the ablation time is one of the main concerns, it is required to reduce it below the standard time (≈7.3 min). The ablation time can be reduced by injecting the nanoparticles into the tumor. In this paper, numerical studies are conducted on PAG phantom to analyze the effect of nanoparticle assisted RFA on the ablation time. Results indicate that in case of nanoparticles assisted RFA, heat conduction rate increases and takes lesser time (17.56% less) to ablate the tumor completely than that in conventional RFA. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item A review on thermal energy storage using composite phase change materials(Bentham Science Publishers, 2018) Chavan, S.; Gumtapure, V.; Arumuga Perumal, D.A.Background: This paper intends to provide the elementary understanding about the development of thermal energy storage systems. Reviews of storage system performance are carried out from various characterization studies, experimental work, numerical investigations and patents. Several techniques employed to enhance the thermal performance have been reviewed and discussed. Composite phase change materials are the best alternative to achieve the cost feasibility in thermal energy storage systems without compromising the storage capacity. Objective: The purpose of this study is to give an outline and history of the thermal energy storage systems and enlighten the techniques used for storage density enhancement without significant modifications in the design. Methods: In this study, three methods such as, characterization studies, experimental work, numerical investigations and patents. It also addresses many research articles and recent patents on the thermal storage systems, various techniques adopted and applications of such systems. Results: Composite phase change materials are the best alternative to achieve the cost feasibility in thermal energy storage systems without compromising the storage capacity. Carbon based nanoparticles show excellent properties in the composite phase change materials. Conclusion: Composite phase change materials have greater potential for thermal energy storage applications and especially carbon-based nanoparticles like graphene, graphene oxide, carbon nanotubes, fullerene, graphite, graphite oxide, extracted graphite etc., are greatly enhancing the thermo-physical properties of composite phase change materials. Combination of paraffin-based phase change materials and carbon-based nanoparticles can be used for the future thermal energy storage applications. © 2018 Bentham Science Publishers.Item Potential of Chitosan and its derivatives for controlled drug release applications – A review(Editions de Sante editions.de.sante@wanadoo.fr, 2019) Safdar, R.; Omar, A.A.; Arunagiri, A.; Iyyaswami, R.; Murugesan, M.Recent research on the drug delivery systems exhibited tremendous improvements for several short life drugs which disappear in few minutes in harsh conditions of the Gastrointestinal tract (GIT). After years of investigations, the current drug delivery system has been improved with new advanced materials with less toxicity and better therapeutic efficiency. In this regard, new formulations consisting of drugs encapsulated with natural biodegradable copolymer, Chitosan, in the form of nanoparticles have been studied, which in turn improved the release profile of drugs. In this review, the Chitosan and its physiochemical properties, nanoparticles and their drug release mechanism and effects of modification of various drugs (anti–cancer, anti–inflammatory, anti–diabetes, anti–infectious drugs etc) with Chitosan and co–materials on their release profiles are briefly reviewed. These biodegradable polymeric nanoparticles improved the in vitro release profile of drugs and provided a way forward for further improvement of the current and conventional drug delivery systems. © 2018 Elsevier B.V.Item Critical heat flux enhancement in pool boiling using alumina nanofluids(2010) Hegde, R.N.; Rao, S.S.; Reddy, R.P.The pool boiling characteristics of dilute dispersions of alumina nanoparticles in water were studied. Consistent with other nanofluid studies, it was found that a significant enhancement in critical heat flux (CHF) can be achieved at modest nanoparticle concentrations (<0.1% by volume). During experimentation and subsequent inspection, formation of a porous layer of nanoparticles on the heater surface occurred during nucleate boiling. This layer significantly changes surface texture of the heater wire surface which could be the reason for improvement in the CHF value. © 2010 Wiley Periodicals, Inc.Item Role of surface roughness in pool boiling with Alumina-water nanofluid on a horizontal wire surface(International Information and Engineering Technology Association, 2011) Hegde, R.N.; Rao, S.S.; Reddy, R.P.Boiling heat transfer is one of the major phenomenon which of late, has drawn the attention of many researchers and scientists throughout the world. With nanofluids, further boost is given in heat transfer enhancement. This research paper is the study of heat transfer enhancement using Alumina nanofluid in different volume concentrations ranging from 1 to 9%. The role of surface roughness on critical heat flux enhancement (CHF) in pool boiling with nanofluids was experimentally studied using a 36 gauge NiCr wire at atmospheric pressure. Experimentation included i) investigations on boiling heat transfer subjecting the wire surface to Alumina nanofluid at higher volume concentrations and ii) investigations on surface roughness due to surface coating, subjecting the wire surface to a single heating cycle with different volume concentrations of Alumina nanofluid. Boiling of nanofluid resulted in nanoparticle deposition and subsequent roughning of the wire surface. To substantiate the nanoparticle deposition and its effect on critical heat flux, investigation was done by studying the surface roughness and SEM images of the wire surface. The experimental results show the evidence of nanoparticle deposition on the wire surface and its effect on CHF enhancement and deterioration in pool boiling heat transfer.Item Crystallinity, conductivity, and magnetic properties of PVDF-Fe 3O4 composite films(2011) Bhatt, A.S.; Bhat, D.K.; Santosh, M.S.The formation of Fe3O4 nanoparticles by hydrothermal process has been studied. X-ray Diffraction measurements were carried out to distinguish between the phases formed during the synthesis. Using the synthesized Fe3O4 nanoparticles, poly(vinyledene fluoride)-Fe3O4 composite films were prepared by spin coating method. Scanning electron microscopy of the composite films showed the presence of Fe3O4 nanoparticles in the form of aggregates on the surface and inside of the porous polymer matrix. Differential Scanning calorimetry revealed that the crystallinity of PVDF decreased with the addition of Fe3O4. The conductitivity of the composite films was strongly influenced by the Fe3O4 content; conductivity increased with increase in Fe3O4 content. Vibration sample magnetometry results revealed the ferromagnetic behavior of the synthesized iron oxide nanoparticles with a Ms value of 74.50 emu/g. Also the presence of Fe3O4 nanoparticles rendered the composite films magnetic. © 2010 Wiley Periodicals, Inc.