Nanoflake NiMoO₄ based smart supercapacitor for intelligent power balance monitoring

Chavan, Harish S.,Hou, Bo,Ahmed, Abu Talha Aqueel,Jo, Yongcheol,Cho, Sangeun,Kim, Jongmin,Pawar, Sambhaji M.,Cha, SeungNam,Inamdar, Akbar I.,Im, Hyunsik,Kim, Hyungsang North-Holland 2018 Solar energy materials and solar cells Vol.185 No.-

<P><B>Abstract</B></P> <P>A supercapacitor is well recognized as one of emerging energy sources for powering electronic devices in our daily life. Although various kind of supercapacitors have been designed and demonstrated, their market aspect could become advanced if the utilisation of other physicochemical properties (e.g. optical) is incorporated in the electrode. Herein, we present an electrochromic supercapacitor (smart supercapacitor) based on a nanoflake NiMoO<SUB>4</SUB> thin film which is fabricated using a facile and well-controlled successive ionic layer adsorption and reaction (SILAR) technique. The polycrystalline nanoflake NiMoO<SUB>4</SUB> electrode exhibits a large electrochemically active surface area of ~ 96.3 cm<SUP>2</SUP>. Its nanoporous architecture provides an easy pathway for the intercalation and de-intercalation of ions. The nanoflake NiMoO<SUB>4</SUB> electrode is dark-brown in the charged state and becomes transparent in the discharged state with a high optical modulation of 57%. The electrode shows a high specific capacity of 1853 Fg<SUP>–1</SUP> at a current rate of 1 Ag<SUP>–1</SUP> with a good coloration efficiency of 31.44 cm<SUP>2</SUP>/C. Dynamic visual information is obtained when the electrode is charged at different potentials, reflecting the level of energy storage in the device. The device retains 65% capacity after 2500 charge-discharge cycles compared with its initial capacity. The excellent performance of the nanoflake NiMoO<SUB>4</SUB> based smart supercapacitor is associated with the synergetic effect of nanoporous morphology with a large electrochemically active surface area and desired chemical composition for redox reaction.</P> <P><B>Highlights</B></P> <P> <UL> <LI> A smart device with the combined advantages of energy storage and electrochromism is presented. </LI> <LI> It is dark-brown in the charged state and transparent in the discharged state. </LI> <LI> It exhibits a coloration efficiency of ~31.44 cm<SUP>2</SUP>/C and optical modulation of 57% at 630 nm. </LI> <LI> It shows specific capacity of 1853 F/g, with 65% capacity retention after 2500 cycles. </LI> </UL> </P>

Rapid One-pot, Four Component Synthesis of Pyranopyrazoles Using Heteropolyacid Under Solvent-free Condition

Chavan, Hemant V.,Babar, Santosh B.,Hoval, Rahul U.,Bandgar, Babasaheb P. Korean Chemical Society 2011 Bulletin of the Korean Chemical Society Vol.32 No.11

A series of pyranopyrazoles, was efficiently synthesized via one-pot, four component reaction of ethyl acetoacetate, hydrazine hydrate, aldehydes and malononitrile in the presence of catalytic amount silicotungstic acid under solvent free condition. NOE experiments confirmed that the product exist exclusively in the 2H form. The present protocol offers the advantages of clean reaction, short reaction time, high yield, easy purification and economic availability of the catalyst.

Nonparametric two sample tests for scale parameters of multivariate distributions

Chavan, Atul R,Shirke, Digambar T The Korean Statistical Society 2020 Communications for statistical applications and me Vol.27 No.4

In this paper, a notion of data depth is used to propose nonparametric multivariate two sample tests for difference between scale parameters. Data depth can be used to measure the centrality or outlying-ness of the multivariate data point relative to data cloud. A difference in the scale parameters indicates the difference in the depth values of a multivariate data point. By observing this fact on a depth vs depth plot (DD-plot), we propose nonparametric multivariate two sample tests for scale parameters of multivariate distributions. The p-values of these proposed tests are obtained by using Fisher's permutation approach. The power performance of these proposed tests has been reported for few symmetric and skewed multivariate distributions with the existing tests. Illustration with real-life data is also provided.

Ultrathin Ni-Mo oxide nanoflakes for high-performance supercapacitor electrodes

Chavan, Harish S.,Hou, Bo,Ahmed, Abu Talha Aqueel,Kim, Jongmin,Jo, Yongcheol,Cho, Sangeun,Park, Youngsin,Pawar, Sambhaji M.,Inamdar, Akbar I.,Cha, Seung Nam,Kim, Hyungsang,Im, Hyunsik Elsevier 2018 Journal of Alloys and Compounds Vol.767 No.-

<P><B>Abstract</B></P> <P>Supercapacitors based on nanomaterial electrodes exhibit great potential as power sources for advanced electronic devices. From a practical viewpoint, it is desirable to fabricate highly active and sustainable nanomaterial electrodes consisting of non-precious elements using a simple technique in a controllable way. In this work, we report the synthesis of a self-assembled ultra-thin porous nanoflake Ni-Mo oxide (NMO) film using the successive ionic layer adsorption and reaction (SILAR) technique. The nanoflake NMO thin film electrode with a large electrochemically active surface area of ∼108 cm<SUP>−2</SUP> exhibits a high specific capacitance of 1180 Fg<SUP>−1</SUP> at a current density of 1 Ag<SUP>−1</SUP> and excellent rate capability, with a negligible capacity loss of 0.075% per cycle. Even at a high current rate of 10 A g<SUP>−1</SUP> it retains a capacity of 600 Fg<SUP>−1</SUP>. The highest energy and power densities obtained are 119 Whkg<SUP>−1</SUP> and 15.7 kWkg<SUP>−1</SUP>, respectively. Electrochemical impedance spectroscopy analyses reveal that the electrode has considerably low charge transfer resistance. The observed excellent electrochemical energy storage performance of the nanoflake NMO electrode with a nanoporous surface is due to the synergetic effects of the large electrochemically active surface area, enhanced ion diffusion, and improved electrical conductivity.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ultra-thin porous Ni-Mo oxide nanoflakes self-assemble on stainless steel via a SILAR method. </LI> <LI> Large electrochemically-active surface area, enhanced ion diffusion and robust adhesion result in superior performance. </LI> <LI> High specific capacitance of 1180 F/g and energy density of 119 Wh/kg at 1 A/g are achieved. </LI> </UL> </P>

Antibiotic resistance profiling and valorization of food waste streams to starter culture biomass and exopolysaccharides through fed-batch fermentations

Chavan Priyanka Yashwant,Vijay Rajendran,Srinivasan Krishnamoorthy,Baskaran Nagarathinam,Ashish Rawson,Arunkumar Anandharaj,Vignesh Sivanandham 한국식품과학회 2023 Food Science and Biotechnology Vol.32 No.6

The present study evaluated antibiotic resistance (ABR) in bacteria isolated from different food wastes viz., meat slaughterhouses, dairy and restaurants. About 120 strains isolated from the food waste were subjected to ABR screening. More than 50% of all the strains were resistant to Vancomycin, Neomycin and Methicilin, which belong to third-generation antibiotics. Two lactic acid bacteria (LAB) free of ABR were chosen to be used as starter cultures in media formulated from food waste. Food waste combination (FWC-4) was found to be on par with the nutrient broth in biomass production. The non-ABR LAB strains showed excellent probiotic properties, and in the fed-batch fermentation process, adding a nitrogen source (soya protein) enhanced the microbial biomass (3.7 g/l). Additionally, exopolysaccharide production was found to be 2.3 g/l. This study highlights the ABR incidence in food waste medium and its economic advantage for starter culture biomass production.

The Buddha's Words and Electronic Media

Chavan, Dhananjay 동국대학교 전자불전연구소 2001 전자불전 Vol.3 No.-

Chattha Sangayana (Sixth Council) Edition’s usefulness for electronic media : One of the biggest difficulties in text inputting projects is that when one wants to convert this data into a user-friendly electronic form, thousands of man-hours of scholars are needed for editing. Thus we see that there are many such projects which end up being mere collection of the texts. When VRI made the pali Canon widely available by harnessing the electronic media, it benefited immensely from the work of editing done by Sixth Council. Thus, most of the credit for VRI’s work goes to the Sixth Council. After a brief review of VRI’s efforts in digitalisation of pali texts, We shall see how the massive work of editing of about 50000 pages of Pali texts was done during the Sixth council with remarkable wisdom, consistency and accuracy. The Sixth council edition stands the test of consistency and accuracy required for software programmes making it one of the finest and most intricately interconnected electronic text of ancient scriptures. It was as if the Sixth Council knew beforehand the rigorous demands placed on data for it to be used easily by software programmers to render it into a lucid inter-linked user-friendly source. We shall also see how the editors of the Sixth Council have done much more that still needs to be exploited to make it an even more useful source of data. The electronic text places greater demand on the scholars involved in preparation of the text in electronic form.

A Versatile and Practical Synthesis of 1, 8-Dioxo-octahydroxanthene Derivatives Catalyzed by Polyethylene Glycol (PEG) in Water

Chavan, Abhijit P. Korean Chemical Society 2009 대한화학회지 Vol.53 No.4

수용액에서 다양한 알데히드 5, 5-dimethyl-1, 3-cyclohexanedione을 이용한 1, 8-Dioxo-octahydroxanthene 유도체의 편리하고 실용적인 합성이 촉매인 폴리에틸렌 글리콜(PEG)하에서 성공적으로 수행되었다. 간단한 work-up, 깨끗한 생성물, 높은 수율, 친환경적인 용매인 물의 사용은 이 방법의 특색이다. A convenient and practical synthesis of 1, 8-dioxo-octahydroxanthene derivatives using various aldehydes, 5, 5-dimethyl-1, 3-cyclohexanedione in water was successfully carried out in the presence of polyethylene glycol (PEG) as a catalyst. Simple work-up, clean products, high yields and water as a green solvent are the attractive features of this methodology.

Geometrical nonlinear bending characteristics of SWCNTRC doubly curved shell panels

Chavan, Shivaji G.,Lal, Achchhe Techno-Press 2018 Advances in aircraft and spacecraft science Vol.5 No.1

In this paper, geometric nonlinear bending characteristics of single wall carbon nanotube reinforced composite (SWCNTRC) doubly curved shell panels subjected to uniform transversely loadings are investigated. The nonlinear mathematical model is developed for doubly curved SWCNTRC shell panel on the basis of higher-order shear deformation theory and Green- Lagrange nonlinearity. All nonlinear higher order terms are included in the mathematical model. The effective material properties of SWCNTRC are estimated by using Eshelby-Mori-Tanaka micromechanical approach. The governing equation of the shell panel is obtained using the total potential energy principle and a Newton-Raphson iterative method is employed to compute the nonlinear displacement and stresses. The present results are compared with published literature. The effect of SWCNT volume fraction, width-to-thickness ratio, radius-to-width ratio (R/a), boundary condition, linear and nonlinear deflection, stresses and different types of shell geometry on nonlinear bending response is investigated.

Role of Different Oxide to Fuel Ratios in Solution Combustion Synthesis of SnO₂ Nanoparticles

Chavan, Archana U.,Kim, Ji-Hye,Im, Ha-Ni,Song, Sun-Ju The Korean Ceramic Society 2016 한국세라믹학회지 Vol.53 No.1

Tin oxide ($SnO_2$) nanoparticles have been synthesized by solution combustion method using citric acid as a fuel. The oxide to fuel ratio has been varied to obtain ultrafine nanoparticles with better surface area; such particles will be useful in many applications. With this synthesis method, spherical particles are formed having a particle size in the range of 11-30 nm and BET surface area of ~ $24m^2/g$. The degree of agglomeration of $SnO_2$ nanoparticles has been calculated.

Adverse events associated with third space endoscopy: Diagnosis and management

Radhika Chavan,Zaheer Nabi,Duvuur Nageshwar Reddy 소화기인터벤션의학회 2020 Gastrointestinal Intervention Vol.9 No.2

Third space endoscopy (TSE) is a ‘magnum opus’ in the field of therapeutic gastrointestinal (GI) endoscopy that has led to a paradigm shift in the management of various GI disorders. TSE or submucosal endoscopy is based on the concept of mucosal flap safety valve technique. Since, the basic principle is more or less similar for all the TSE procedures, the nature of major adverse events (AE) also shares some similarity across the spectrum of TSE procedures. These AE include insufflation related AE, bleeding, perforation, and infection. Insufflation related events are among the most commonly encountered AEs. However, majority of the insufflation related AE do not require a specific intervention and not regarded as AE in true sense. Identification of risk factors and adaptation of preventative strategies may help in reducing the incidence of AE. At the same time, early recognition and expeditious management is paramount to reduce morbidities associated with these AE. Due to heterogeneity in the reporting of AE, it is difficult to estimate the actual incidence of AE and compare the results between different studies. Therefore, universal adaptation of a standard reporting system is required to quantify the true incidence of AE for each procedure.