Papers by Dr. Raviraj Kulkarni
Electro-sensing base for mefenamic acid on a 5% barium-doped zinc oxide nanoparticle modified electrode and its analytical application
RSC Adv.
In the present work, surface enhanced electro-oxidation of mefenamic acid (MFA) at a glassy carbo... more In the present work, surface enhanced electro-oxidation of mefenamic acid (MFA) at a glassy carbon electrode modified with 5% barium doped ZnO nanoparticles was studied.
A review on synthesis, functionalization, processing and applications of graphene based high performance polymer nanocomposites
Current Nanoscience, 2021
Graphene as a nanofiller has gained tremendous importance in polymer nanocomposites for many appl... more Graphene as a nanofiller has gained tremendous importance in polymer nanocomposites for many applications. The attractive properties of graphene related to mechanical, electrical, and thermal domains pose a lucrative means of reinforcing the polymers to obtain the needed properties. The rise in the use of polymers supports this trend and urges the researchers to excavate the hidden plethora of nanocomposite materials for multifunctional applications. In this review, an overview is provided on graphene-based materials which have been used extensively in various fields, such as batteries, aerospace, automobile and biomedical fields. An increasing trend of graphene usage by many researchers as a nanofiller in polymer composites, its types, processing methods are highlighted with suitable applications to assimilate the updates in the development of graphene nanocomposites.
Free radical intervention, deamination and decarboxylation in ruthenium (III) catalysed oxidation of
The kinetics of ruthenium(III) catalysed oxidation of rac-serine by permanganate in alkaline medi... more The kinetics of ruthenium(III) catalysed oxidation of rac-serine by permanganate in alkaline medium at a constant ionic strength has been studied spectrophotometrically. The reaction between permanganate and rac-serine inalkaline medium exhibits 2:1 stoichiometry (KMnO 4 :rac-serine). The reaction shows first order dependence on [permanganate] and [ruthenium(III)] and less than unit order dependence each in [rac-serine] and alkali concentrations. Reaction rate increases with increase in ionic strength and with decrease in solvent polarity of the medium. Initial addition of reaction products did not affect the rate significantly. A mechanism involving the formation of a complex between catalyst and substrate is proposed. The activation parameters and the thermodynamic parameters were computed with respect to the slow step of the mechanism. The reaction constants involved in the mechanism were obtained.
Materials
Pure Zn (Zinc) and its Zn–WO3 (Zinc–Tungsten trioxide) composite coatings were deposited on mild ... more Pure Zn (Zinc) and its Zn–WO3 (Zinc–Tungsten trioxide) composite coatings were deposited on mild steel specimens by applying the electrodeposition technique. Zn–WO3 composites were prepared for the concentration of 0.5 and 1.0 g/L of particles. The influence of WO3 particles on Zn deposition, the surface morphology of composite, and texture co-efficient were analyzed using a variety of techniques, such as X-ray diffraction (XRD) and scanning electron microscopy (SEM) with Energy Dispersive X-ray analysis (EDX). Higher corrosion resistance and microhardness were observed on the Zn–WO3 composite (concentration of 1.0 g/L). The higher corrosion resistance and microhardness of 1.0 g/L Zn–WO3 nanocomposite coatings effectively protect the steel used for the manufacture of products, parts, or systems from chemical or electrochemical deterioration in industrial and marine ambient environments.
Aerogel and its composites: fabrication and properties
Advances in Aerogel Composites for Environmental Remediation
Adsorptive removals of pollutants using aerogels and its composites
Advances in Aerogel Composites for Environmental Remediation
Natural aerogels for pollutant removal
Advances in Aerogel Composites for Environmental Remediation
Abstract Aerogels are lightweight, low-density materials derived from organic, inorganic, or hybr... more Abstract Aerogels are lightweight, low-density materials derived from organic, inorganic, or hybrid molecular precursors. Aerogels are 99.8% air. Hence, they are solid gels with a porous network that contain air pockets. Though there are abundant synthetic aerogels available, there are natural aerogels also that are playing important role in the process of pollutant removal. Some of the important natural aerogels are starch, cellulose and other polysaccharides, and natural proteins. Oil removal and separation in case of accidental oil leakage and spillage in oil industries are of great importance. The untreated waste in the form of oil and other contaminants not only results in unnecessary economic loss but are also dangerous to the ecology system. Naturally occurring cotton cellulose aerogel has proven to be a great purifier in such scenarios. The action takes place by absorption mechanism. Cellulose also finds application in the textile industry. The natural proteins like egg white also act as aerogels for applications in the food industry. Use of these natural aerogels has a more significant impact on the purification of air and environment as a whole at this time of contamination being at its peak and growing. This chapter talks in detail about the natural aerogels, their chemical and physical properties, and mechanism of their action as pollutant removers.
Investigations on the effect of nozzle angle and air flow rate during nanofluid Minimum Quantity Lubrication milling of Aerospace alloy Al7075-T6
IOP Conference Series: Materials Science and Engineering
Present day industries are focusing upon finding various methods and techniques to implement sust... more Present day industries are focusing upon finding various methods and techniques to implement sustainable manufacturing, which is ‘the need of the hour’. With increase in global competition, industries are striving hard to reduce the machining costs, which is a major contributor for ‘manufacturing cost per part’, in an industry. Conventional method of using large quantity of coolant/cutting fluids in several liters per hour, to cool machining zone is causing enormous concern. Strict Government regulations are necessitating industries to replace flood-coolant assisted machining by new techniques like ‘Minimum Quantity lubrication’ (MQL) coolant supply technique. The present work deals with investigating the effect of varying nozzle angle and air-flow rate during MQL assisted surface milling of aerospace aluminum Al7075-T6 alloy, using uncoated carbide tool. Three methods of coolant supply namely Dry, MQL and nanofluid MQL (nano particles us pended oil with MQL) are experimented. Cutti...
Ag(I)-Catalyzed Chlorination of Linezolid during Water Treatment: Kinetics and Mechanism
International Journal of Chemical Kinetics
DESALINATION AND WATER TREATMENT
Photo-degradation of pharmaceutical drug zidovudine (ZDV) by synthesized ruthenium doped titanium... more Photo-degradation of pharmaceutical drug zidovudine (ZDV) by synthesized ruthenium doped titanium dioxide nanoparticles (RDTDONPs) at 254 nm and pH (4.0 to 8.0) was investigated. 0.2%, 0.4%, 0.6%, and 0.8% (mole ratio) RDTDONPs were prepared by liquid impregnation method and characterised by different sophisticated techniques. Three photo-degraded products of ZDV are analysed. The photo-generated electron-hole pair mechanism was proposed in agreement with kinetic data. The calculated average crystallite size of 0.8% (mole ratio) RDTDONPs is 14.38 nm using the Scherrer equation. This smaller average crystallite size of 0.8% (mole ratio) RDTDONPs enhances the rate of mineralization due to the increase in surface area of nanoparticles. The effect of different parameters on the rate of mineralization of ZDV was investigated. The rate of mineralization of ZDV increases with the initial increase in [ZDV]. The rate of mineralization of ZDV was found higher in acidic conditions than alkaline conditions. Experimental results show that the rate of mineralization of ZDV moiety was found to be increased with an increase in the dosage of 0.8% (mole ratio) RDTDONPs. The rate of mineralization of ZDV was found to be increased with an increase in % doping of ruthenium from 0.2% to 0.8% (mole ratio) and then decreased beyond 0.8% ruthenium doping. The kinetic data reveals that the rate of mineralization of ZDV increases with an increase in light intensity.
Enhancement of Coefficient of Performance for Polyalkylene Glycol (PAG) Oil with Addition of Silver Nanoparticles for Refrigerant Application
Journal of Advanced Research in Dynamical and Control Systems
Electroanalysis of Carbendazim using MWCNT/Ca-ZnO Modified Electrode
Electroanalysis
Electrochemical behavior of diclofenac sodium at coreshell nanostructure modified electrode and its analysis in human urine and pharmaceutical samples
Sensors International
Abstract In this contemporary consideration, a novel coreshell nanostructures modified sensor bas... more Abstract In this contemporary consideration, a novel coreshell nanostructures modified sensor based on carbon electrode was engineered which achieved enhanced sensitivity towards Diclofenac. The electrochemical behavior and applications of Diclofenac (DCF) was determined by applying discrete voltammetric techniques. The surface characteristic was accomplished using atomic force microscopy (AFM). The proposed modified electrode showed strong electro catalytic activity and electro oxidation towards DCF with higher peak shift as equated to the bare electrode. The modified electrode possesses unique qualities such as fast transfer of electrons, constancy, repeatability and reproducibility. The various performances feigning the peak improvement such as accumulation time, pH, scan rate, modifier amount, and concentration impingements were considered. The electro-oxidation of DCF was studied by cyclic voltammetry (CV) and concentration effect was read using square wave voltammetry (SWV) technique in the concentration range of about 0.01 μM–300 μM. The limit of detection (LOD) was deliberated to be 3.41 × 10-8 M and quantification (LOQ) was 11.3 × 10-8 M, correspondingly. The pertinency of the purposed way was checked by quantification of DCF in pharmaceutic formulations and human urine samples. The mean of recovery of DCF in the tablet was 97.5%, with relative standard deviation of 0.7%.
Synergetic effect of rubber on the tensile and flexural properties of graphene based epoxy-carbon fiber hybrid nanocomposite
Materials Today: Proceedings
Abstract The interaction effects of rubber addition on the tensile and flexural characteristics o... more Abstract The interaction effects of rubber addition on the tensile and flexural characteristics of hybrid composites of Epoxy-carbon fiber with Graphene as nanofiller were studied. Bisphenol resin was used as matrix. The epoxy-carbon fiber composite was modified with 0.1, 0.2 and 0.3 wt% of graphene. The specimens with 0.1% graphene exhibited significant rise in tensile and flexural strength whereas on further addition of graphene with 0.2 and 0.3% the strength improved marginally compared to epoxy-carbon fiber composite. 10, 20 and 30% by weight natural rubber in liquid form was added to epoxy-carbon fiber with 0.1% graphene, which further enhanced the tensile and flexural characteristics of the hybrid composite. The specimens with 10% rubber reinforcement exhibited a nominal improvement in the tensile and flexural strength of the hybrid composite whereas the specimens with 20% rubber showed acceptable rise in the tensile and flexural strength. Upon further addition of rubber by 30% the strength decreased marginally. The SEM results for different configurations were analyzed to study the morphological and interfacial interactions.
Applied Water Science
In this paper, an attempt has been made to develop a statistical model based on Internet of Thing... more In this paper, an attempt has been made to develop a statistical model based on Internet of Things (IoT) for water quality analysis of river Krishna using different water quality parameters such as pH, conductivity, dissolved oxygen, temperature, biochemical oxygen demand, total dissolved solids and conductivity. These parameters are very important to assess the water quality of the river. The water quality data were collected from six stations of river Krishna in the state of Karnataka. River Krishna is the fourth largest river in India with approximately 1400 km of length and flows from its origin toward Bay of Bengal. In our study, we have considered only stretch of river Krishna flowing in state of Karnataka, i.e., length of about 483 km. In recent years, the mineral-rich river basin is subjected to rapid industrialization, thus polluting the river basin. The river water is bound to get polluted from various pollutants such as the urban waste water, agricultural waste and indust...
TiO2 nanoparticles modified sensor for theophylline drug
Materials Today: Proceedings
Abstract A simple modified sensor has been proposed using titanium dioxide (TiO2) nanoparticles f... more Abstract A simple modified sensor has been proposed using titanium dioxide (TiO2) nanoparticles for the electro-analysis of theophylline (TP) in phosphate buffer solution (PBS). The surface was characterized by atomic mass spectroscopy (AFM). The electro-oxidation of the drug was studied by employing techniques such cyclic voltammetry (CV) and square wave voltammetry (SWV). The heterogeneous rate constant was calculated and a suitable electrochemical oxidation mechanism was also proposed. The concentration variation of the drug showed good linear response with lower detection limit value. The influence of physic-chemical parameters like scan rate, pH, accumulation time, and amount of the modifier, excipients, metal ions and concentration on the voltammetric behavior of an analyte were studied. To test its analytical applications it was applied to determine drug in pharmaceutical and urine samples with good recovery values.
Development of a sensor for thiosalicylic acid at MWCNT modified gold
Materials Today: Proceedings
Abstract Development of nano level based sensor for the electrochemical performance of thiosalicy... more Abstract Development of nano level based sensor for the electrochemical performance of thiosalicylic acid by fabrication of multiwalled carbon nanotubes on glassy carbon electrode was made. Employing cyclic voltammetry and square wave voltammetry techniques in pH 4.2 phosphate buffer solution, parameters effect was estimated by varying pH, accumulation time, scan rate, excipients, and analyte concentration. Number of electrons, protons involved in the reactions and also heterogeneous rate constant value was determined. The proposed sensor was applied for the determination of analyte in pharmaceutical and human urine samples. The linear response was obtained in the concentration range studied with lower quantification limit value. Reaction mechanism for electrochemical oxidation of thiosalicylic acid was proposed. The modified sensor showed an excellent sensitivity, reproducibility, repeatability etc.
ZnO nanoparticles modified sensor for the electroanalysis of thiosalicylic acid
Materials Today: Proceedings
Abstract A nano level detection of thiosalicylic acid and its analysis by sensing method has been... more Abstract A nano level detection of thiosalicylic acid and its analysis by sensing method has been developed at zinc oxide nanoparticles modified glassy carbon electrode by employing voltammetric techniques in pH 3.0. The modified sensor was subjected to test the influence of parameters like pH, accumulation time for thiosalicylic acid drug was studied by employing cyclic voltammetry and scan rate, excipients, thiosalicylic acid concentration variation by using square wave voltammetry technique for quantitative determination in phosphate buffer. Heterogeneous rate constant value was also determined. The zinc oxide nanoparticles modified glassy carbon electrode sensor was employed for the determination of thiosalicylic acid in pharmaceutical samples. The concentration range studied in square wave voltammetry technique exhibits lower values of detection limit and quantification of thiosalicylic acid. A possible mechanism of electrochemical oxidation of thiosalicylic acid was proposed.
Annales de Chimie - Science des Matériaux
The objective of this research work is to synthesize Alumina@Copper, core@shell nanoparticles sus... more The objective of this research work is to synthesize Alumina@Copper, core@shell nanoparticles suspended nanofluid coolant, possessing high thermal conductivity. The Alumina@Copper nanoparticles were synthesized by two step chemical process. The methodology used to synthesize core@shell nanoparticles includes the synthesis of base alumina nanoparticles by sol-gel method in first step, which was coated with a thin shell of copper using electroless plating technique. The study investigates thermal conductivity enhancement of prepared nanofluid coolant, upon suspension of these nanoparticles for the selected volume of Strub Vulcan Futura coolant oil. Nanoparticles addition to the coolant oil was 0.025 % to 0.3 % by weight. Results indicated that, alumina@copper nanoparticles addition enhanced the thermal conductivity value up to 23.39 %. Results were validated using Hamilton and Crosser (HC) theoretical model assuming nanoparticles to be spherical. An empirical correction factor was applied for HC model which fits the thermal conductivity values to justify the deviation. The findings of this research may serve for faster heat dissipation during any metal cutting operation, since the synthesized nanofluid coolant possesses enhanced thermal conductivity.
Research Journal of Pharmaceutical Biological and Chemical Sciences
... 119 Research Journal of Pharmaceutical, Biological and Chemical Sciences In-vitro antioxidant... more ... 119 Research Journal of Pharmaceutical, Biological and Chemical Sciences In-vitro antioxidant activity of Clerodendron inerme (l.) Gaertn leaves Ravindra Kumar Chourasiya1*, Prateek Kumar Jain1, Sunil Kumar Jain1, Siva Sunder Nayak2 and Ram K. Agrawal3 ...
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Papers by Dr. Raviraj Kulkarni