Concomitant endoscopic biliary, duodenal and colonic stent placement for advanced carcinoma of gall bladder

Sridhar Sundaram,Sidharth Harindranath,Praveen Kumar Rao,Nitin Ramani,Aditya Kale,Shraddha Patkar 소화기인터벤션의학회 2021 International journal of gastrointestinal interven Vol.10 No.4

Combined biliary and duodenal stent placement has been reported previously in multiple series. Rarely, colonic obstruction may present simultaneously with duodenal and biliary obstruction in advanced pancreaticobiliary cancers. Biliary, duodenal and colonic obstruction managed simultaneously using endoscopic modalities have been reported in only one case report previously. Here we report outcomes of a case of carcinoma of the gall bladder with biliary, gastric outlet and colonic obstruction managed by endoscopic placement of biliary, gastroduodenal and colonic self-expanding metal stents.

Manganese nitride stabilized on reduced graphene oxide substrate for high performance sodium ion batteries, super-capacitors and EMI shielding

Sridhar, Vadahanambi,Park, Hyun Elsevier 2019 JOURNAL OF ALLOYS AND COMPOUNDS Vol.808 No.-

<P><B>Abstract</B></P> <P>Though the utility of manganese compounds such as oxides, sulphides has been well researched in energy storage applications such as super-capacitors and lithium-ion batteries, the utility of manganese nitrides hasn't been reported yet, especially as anode in sodium-ion batteries. In this manuscript we report synthesis of manganese nitride decorated reduced graphene oxide (MnN@rGO) prepared by simple microwave nitridation technique and its utility as anode material in sodium-ion batteries, electrodes in super-capacitors and in EMI shielding applications. In energy storage applications such as sodium ion batteries, MnN@rGO electrodes exhibited sodium storage capacity of 716 mAhg<SUP>−1</SUP> whereas when used as electrodes in super-capacitors, a high capacitance value of 639.2 Fg<SUP>-1</SUP> at scan rates of 10 mVs<SUP>−1</SUP> in 1 M Na<SUB>2</SUB>SO<SUB>4</SUB> aqueous electrolyte was achieved. The EMI shielding effectiveness measured in the X-band region of 2–18 GHz was about 30–32 dB which is 300% more than reduced graphene oxide.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We report microwave synthesis of manganese nitride nano-particles dispersed on reduced graphene oxide substrate (MnN@rGO). </LI> <LI> The applicability of MnN@rGO in sodium-ion batteries, super-capacitors and EMI shielding applications is reported. </LI> <LI> The versatility of our newly developed technique to synthesize MnN nanoparticles on carbon fibers is also demonstrated. </LI> </UL> </P>

Microwave synthesis of three dimensional graphene-based shell-plate hybrid nanostructures

Sridhar, V.,Lee, I.,Yoon, H.S.,Chun, H.H.,Park, H. Pergamon Press ; Elsevier Science Ltd 2013 Carbon Vol.61 No.-

Though free standing graphene has excellent physical, chemical and electrical properties, its tendency to restack is a major hurdle in realizing its full potential especially in applications such as lithium ion batteries and super capacitors. In this manuscript, we report synthesis of graphene-based three dimensional (3D) shell-plate nanostructures composed of 'nano-cup arrays' anchored on few-layered graphene (FLG) substrates. The synthesis was carried out by a simple process using eco-friendly ionic liquids and microwave irradiation as the energy source. Morphological studies by scanning electron microscopy and transmission electron microscopy showed vertically anchored graphene nano-cups on graphene substrate. Super capacitor electrodes fabricated with FLG/gCup nano-hybrids and its electrochemical properties are studied by cyclic voltammetry (CV) and galvanostatic charge/discharge (DC) methods. FLG/gCup electrodes showed good electrochemical performance, with a maximum specific capacitance of 421Fg<SUP>-1</SUP> at the charge/discharge current density of 100mAg<SUP>-1</SUP> in 1M KOH electrolyte, which is four times higher than pristine graphene sheets. The utility of our developed technique in synthesis of graphene nano-cup arrays on arbitrary surfaces (glass substrate) is also reported.

Damage evaluation of RC beams strengthened with hybrid fibers

Sridhar, Radhika,Prasad, Ravi Techno-Press 2019 Advances in concrete construction Vol.8 No.1

This paper describes an experimental investigation on hybrid fiber reinforced concrete (HYFRC) beams. And the main aim of this present paper is to examine the dynamic characteristics and damage evaluation of undamaged and damaged HYFRC beams under free-free constraints. In this experimental work, totally four RC beams were cast and analyzed in order to evaluate the dynamic behavior as well as static load behavior of HYFRCs. Hybrid fiber reinforced concrete beams have been cast by incorporating two different fibers such as steel and polypropylene (PP). Damage of HYFRC beams was obtained by cracking of concrete for one of the beams in each set under four-point bending tests with different percentage variation of damage levels as 50%, 70% and 90% of maximum ultimate load. And the main dynamic characteristics such as damping, fundamental natural frequencies, mode shapes and frequency response function at each and every damage level has been assessed by means of non-destructive technique (NDT) with hammer excitation. The fundamental natural frequency and damping values obtained through dynamic tests for HYFRC beams were compared with control (reference) RC beam at each level of damage which has been acquired through static tests. The static experimental test results emphasize that the HYFRC beam has attained higher ultimate load as compared with control reinforced concrete beam.

Outcomes and predictors of response to endotherapy in pancreatic ductal disruptions with refractory internal and high-output external fistulae

Sridhar Sundaram,Biswa Ranjan Patra,Dhaval Choksi,Suprabhat Giri,Aditya Kale,Nitin Ramani,Abhijeet Karad,Akash Shukla 한국간담췌외과학회 2022 Annals of hepato-biliary-pancreatic surgery Vol.26 No.4

Tunnel Recognition for Vision Based Driver Assistance System

Sridhar S,Jitesh K. Singh,Roh Seung Hyun 한국자동차공학회 2011 한국자동차공학회 학술대회 및 전시회 Vol.2011 No.11

Detecting changes in the environment while driving is critical in any vision based driving assistance system. These environmental changes have to be handled separately to enhance ADAS (advanced driver assistance system) performance. In particular, this paper focuses on detecting tunnel using a simple and computationally efficient approach. Conventional tunnel detection approaches use tunnel entry and exit information for its recognition. These approaches fail for different tunnel cases and during night condition. In this paper, we propose tunnel recognition algorithm using the pattern of lights available inside the tunnel. The first order line fitting algorithm is used to track the tunnel lights, which almost follow straight lines. The magnitude of error in line fitting decides whether the image has a tunnel or not. It has been observed that the intensity inside the tunnel is less compared to outside environment during day condition. Using this criterion, brightness parameter is calculated to avoid unnecessary processing of normal day image. The proposed algorithm has been tested on both day and night images captured from grayscale monocular camera mounted on the ego vehicle.

Dielectric and dynamic mechanical relaxation behavior of exfoliated nano graphite reinforced flouroelastomer composites

Sridhar, V.,Xu, Deng,Pham, Thanh Tu,Mahapatra, S.P.,Kim, Jin Kuk Wiley Subscription Services, Inc., A Wiley Company 2009 Polymer composites Vol.30 No.3

<P>Dynamic mechanical analysis and dielectric relaxation spectra of exfoliated nano graphite reinforced flouroelastomer composites were used to study their relaxation behavior as a function of temperature (−80°C to +40°C) and frequency (0.01 to 10<SUP>5</SUP> Hz). The effect of filler loadings on glass transition temperature was marginal for all the composites and T<SUB>g</SUB> value was in the narrow range of 7.8–8.4°C, which has been explained on the basis of relaxation dynamics of polymer chains in the vicinity of fillers. Strain-dependent dynamical parameters were evaluated at dynamic strain amplitudes of 0.01–10%. The nonlinearity in storage modulus has been explained on the concept of filler-polymer interaction and filler aggregation of the nano graphite platelets. The variation in real and complex part of impedance with frequency has been studied as a function of filler. The percolation of the nano graphite as studied by conductivity measurements is also reported. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers.</P>

Sediment geochemistry with population of recent benthic ostracoda in Palk Bay, southeast coast of India

Sridhar G.D. Sithu,Baskar Kuppusamy,Maniyarasan Subramaniyan,Hussain M. Sheik 한국지질과학협의회 2016 Geosciences Journal Vol.20 No.2

Seasonal observation on trace elements of shallow inner shelf sediments and their correlation with the population of recent benthic ostracoda off Rameswaram, Ramanathapuram District, Tamil Nadu, Southeast coast of India is the aim of this study. The sediments were analysed for trace elements Al, Fe, Mn, Zn, Cu, Pb, Cd, Ni, Co and Cr and being correlated with the population of benthic ostracoda for four different seasons. Cu has a positive correlation, and Fe, Mn, Zn, Pb, Cd, Ni, Co and Cr have negative correlation with the total population of ostracoda. Al has no considerable correlation with the total population of ostracoda. In the middle segment plenty of corals were found in the study area and their effect being discussed.

Synthesis of graphene nano-sheets using eco-friendly chemicals and microwave radiation

Sridhar, V.,Jeon, Jin-Han,Oh, Il-Kwon Elsevier 2010 Carbon Vol.48 No.10

<P><B>Abstract</B></P><P>A novel approach to synthesize graphene nano-sheets by combining chemical treatment and microwave radiation is demonstrated using eco-friendly chemicals. Microwave radiation was used to produce strong expansion of the graphite worm in the thickness direction. The graphene nano-sheets obtained in this study were characterized by morphology images, nanoprofilometry, Raman and X-ray photoelectron spectroscopy. Besides being eco-friendly, the proposed method has also the attractive advantage of being rapidly able to produce a lot of graphene nano-sheets.</P>

Novel clays: Solid-state synthesis, characterization and cation exchange selectivity

Sridhar Komarneni,Ramesh Ravella 한국물리학회 2008 Current Applied Physics Vol.8 No.1

Several novel swelling mica-type clays have been synthesized by solid-state processes. Synthetic clays of ideal compositions such asNa2Si6Al2Mg 6O20F4 ÆxH2O (Na-2-mica), Na3Si5Al3Mg 6O20F4 ÆxH2O (Na-3-mica) and Na4Si4Al4Mg 6O20F4 ÆxH2O (Na-4-mica) havebeen prepared and characterized by powder X-ray diraction (XRD), scanning electron microscopy (SEM) and27Al and29Si solid-statemagic angle spinning nuclear magnetic resonance (MASNMR) spectroscopy. Powder XRD showed that all syntheses yielded water swol-len micas withc-axis spacing of. 1.2 nm except in the case of Na-2-mica which also showed a small peak of anhydrous mica phase with ac-axis spacing of 0.96 nm. Solid-state27Al MASNMR spectroscopy revealed that almost all the Al is present in the tetrahedral environ-29Si MASNMR spectroscopy revealed dierent Si (Al) nearest neighbor environments dependingupon the composition of the various micas. Selective cation exchange studies were performed on the various micas using 0.5 N NaClsolution containing 12.9 ppm Sr2+ or 8.12 ppm of La3+. The results showed, for the rst time, that Na-3-mica has a high selectivityfor the trivalent cation tested. The previously reported high selectivity of these synthetic micas for the divalent cations has been con-rmed. These selective cation exchange studies are of relevance in cation separations from drinking and waste waters.