Sivasangari Velmurugan

Amrita Vishwa Vidyapeetham | AMRITA · Center for Cybersecurity

Carbon steel feeder elbows and feeder piping of the primary coolant system of pressurized heavy water reactors undergo significant wall thinning due to flow accelerated corrosion. The rate of corrosion in certain locations exceeds the design corrosion allowance. Corrosion rate is dependent on several parameters like pH, temperature, dissolved oxyge...

Carbon steel feeders in the primary heat transport system of pressurized heavy water reactors (PHWRs) show significant wall thinning due to flow accelerated corrosion (FAC). This is of great concern, as the wear rate in certain locations exceeds the corrosion allowance by design. This necessitates periodic measurement of wall thickness and in some...

Coolant systems in nuclear power plants undergo degradation by various corrosion processes. The carbon steel feeder pipes for the primary heat transport system of pressurised heavy water reactors (PHWRs) undergo extensive wall thinning by a degradation process, known as flow accelerated corrosion (FAC). Flow accelerated corrosion occurs under certa...

Flow accelerated corrosion (FAC) is an unavoidable problem in the integral part of the pipe line systems of Nuclear Power Plants worldwide. This has a significant influence on the thickness loss of the pipe line which affects the operation and maintenance of the plants. During the prolonged operation of the plants, FAC leads to inside wall thinning...

Reductive dissolution of corrosion product oxides relevant to nuclear power plants such as haematite (Fe 2 O 3 ), nickel ferrite (NiFe 2 O 4 ), iron chromite (FeCr 2 O 4 ) and mixed oxides (NiFe 2-x Cr x O 4 ; x = 0.4, 0.8, 1.2 and 1.6) were carried out in ethylene diamine tetra acetic acid (EDTA) and nitrilo tri acetic acid (NTA) based chemical fo...

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted at the request of the Editor. The article contains an image (Fig. 5B) which was published later again in “Green synthesis of zinc oxide nanoparticles using Morin...

This article has been retracted: please see Elsevier Policy on Article Withdrawal (https://www.elsevier.com/about/our-business/policies/article-withdrawal). This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor...

Nano-crystalline Zirconia (ZrO2) coatings of different thicknesses were grown on pre-oxidized stainless steel (SS) by hydrothermal method in a static autoclave. Hydrothermal deposition process was repeated multiple times in order to enhance the coating thickness. Four cycles of the deposition process led to the development of ~1 μm thick ZrO2 coati...

a free-access multidisciplinary publication of the Faculty of Engineering Hunedoara 1. Abstract: Closed form solution of unsteady hydromagnetic flow past a parabolic starting motion of the infinite vertical plate with variable temperature and mass diffusion, in the presence of homogeneous chemical reaction of first order has been studied. The plate...

The main objective of this work is to see the feasibility of using an electrochemical ion-exchange process in line with decontamination for removal of radioactive metal ions from simulated decontaminated solution/metal ion–loaded cation-exchange resin. This could extend the service period of resin, and the volume of radioactive resin (organic) wast...

The objective of present study is to investigate the influence of bend geometry and the resulting flow phenomenon on the rate of metal loss due to Flow Accelerated Corrosion (FAC). Experiments were carried out with an aggressive chemistry of neutral pH (6.5–7.0) and at a temperature of 120 °C to minimize the time duration required to make unambiguo...

The major structural material employed in the primary coolant system of pressurized heavy water reactors is carbon steel. The formation of corrosion products on the structural material surfaces, transportation to the core by the coolant and deposition of activated corrosion products on the out-of-core surfaces are controlled by several factors. Mag...

Nuclear fuel reprocessing facilities that use tributyl phosphate (TBP) and nitric acid tend to develop a sticky coating of uranium dibutyl phosphate (U-DBP) on their surfaces. This sticky coating also gets formed on the reprocessing waste storage tanks on long standing, which results in radiation exposure hazard. Hence, it is required to periodical...

Gadolinium as gadolinium nitrate is used as neutron poison in the moderator system for regulating and controlling the power generation of Pressurized Heavy Water Reactors (PHWR) and proposed to be used in Advanced Heavy Water Reactors (AHWR) owing to its high neutron absorption cross section. Removal of the added gadolinium nitrate (Gd³⁺ and NO3⁻ f...

Effect of high concentrations of soluble neutron poison gadolinium nitrate, Gd(NO3)3, in the moderator system of a proposed advanced Indian nuclear reactor, was evaluated from the safety point of view. The radiolytic yields of H2 and H2O2 was expected to be high as moderator water system pH would be lowered and conductivity also would be high by th...

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor. The article contains duplicate images (Fig. 5A and B as well as Fig. 5C and D) which differ only in magnification and orientation despite being described a...

This article has been retracted: please see Elsevier Policy on Article Withdrawal (http://www.elsevier.com/locate/withdrawalpolicy). This article has been retracted at the request of the Editor. The article contains an image (Fig. 7D) which originates from an image previously published in the article “Rapid biological synthesis of silver nanopartic...

Removal of antimony, classified as a pollutant of priority importance, is a challenge due to its presence in various forms in solution and the low concentration in which it is to be removed. In this study, sorption profile and the sorption mechanisms associated with the removal of antimony in its two oxidation states (+3 and +5) have been investiga...

Oxidizing environment prevailing in water coolant systems aggravates the corrosion of structural materials. Reducing agents are added to the reactor coolant systems to control the oxidants and mitigate material corrosion. Maintenance of required concentration of the reducing agents in the system and their removal after completing the processes can...

Materials undergo enhanced corrosion in the presence of oxidants in aqueous media. Usually, hydrogen gas or water soluble reducing agents are used for inhibiting corrosion. In the present study, the feasibility of using alternate reducing agents such as hydrazine, aqueous ammonia, and hydroxylamine that can stay in the liquid phase was investigated...

Advanced Heavy Water Reactor (AHWR) is being designed in India with the objective of utilizing the abundant thorium, a fertile material, in the fuel. It is one of the next generation reactor types. It is proposed to use PuO 2 – ThO 2 and 233 UO 2-ThO 2 as fuel in an open cycle. It is a tube type boiling water reactor with a vertical core and uses t...

The structural materials in water-cooled nuclear power reactors are mainly iron and nickel based alloys. Continuous operation of these nuclear reactors at high temperature and high pressure aqueous environment leads to the formation of various oxides due to corrosion of the structural materials. Since the corrosion process is mainly interfacial and...

In recent years, textile waste water has become a serious environmental problem due to vast and increasing uses of variety of dyes such as vat dyes, sulfur dyes, napthol dyes, azo dyes and reactive dyes. Among these varieties reactive dyes are extensively used in textile industry in the last years due to their superior performance, but they are env...

In the present study, the zinc oxide nanoparticles (ZnO NPs) were synthesized from the leaf extract of Vitex trifolia L. GC and GC–MS analyses revealed that the V. trifolia contained 17 compounds. The major chemical components identified were Vitrifolin A (22.11%), 20-hydroxyecdysone (13.78%), 5-Thio d-glucose (10.32%) and 1,1-Bicyclopropyl-2-octan...

Nano-crystalline ZrO2 coatings of different thickness have been grown on pre-oxidized stainless steel (SS) surface by hydrothermal method in an autoclave. Thickness of the coating has been enhanced by repeating the deposition process several times using same precursor concentration. Several cycles of the deposition process lead to the increase of t...

The synthesis of metal and semiconductor nanoparticles is an expanding research area due to the potential applications in the development of novel technologies. Especially, biologically synthesized nanomaterial has become an important branch of nanotechnology. The present work, described the synthesis of Zinc oxide nanoparticles (ZnO NPs) using lea...

The present study focused on the development of zinc oxide nanoparticles (ZnO NPs) from the leaf extract of Murraya koenigii where zinc nitrate acts as the precursor. The X-ray diffraction (XRD) analysis showed the crystalline structure, and atomic force microscopy (AFM) showed the morphology of the ZnO NPs to be spherical with an average size of 1...

Calcium hydroxyapatite (HAP) was synthesized by a precipitation method, and it was characterized by the XRD technique. The removal of manganese(II) from an aqueous solution on HAP as a function of contact time, pH, ionic strength, temperature, and other monovalent and bivalent ions was studied using a radiotracer, 54Mn, in the batch process. The so...

Objective: The controlled release Torsemide matrix tablets were prepared using different natural polymers in various proportions as release retarding agents to control the torsemide release and to improve the patience compliance. Methods: Torsemide matrix tablets were prepared by direct compression method. The matrix tablet is then evaluated for it...

The development of semiconductor materials made a considerable progress of catalytic technologies. In the present study, a simple and eco-friendly chemical direction for the synthesis of zinc oxide nanoparticles (ZnO NPs) using leaf extract of Moringa oleifera has been used. The prepared ZnO NPs were characterized various techniques such as UV-Vis...

Objective: Levodopa is an immediate precursor of dopamine used in treatment of Parkinsonism disorders. The Levodopa effervescent floating tablets were prepared by direct compression technique, using different low density polymers (POLYOX different grades) in various drug polymer ratios. Methods: The Levodopa effervescent floating tablets were prepa...

Objective: The objective of this research was to formulate and evaluate pectin and HPMC different grades mucoadhesive microspheres in combination with sodium alginate for controlled release of maraviroc. Methods: The maraviroc mucoadhesive microspheres was successfully developed by Ionotropic gelation technique, using sodium alginate, pectin, HPMC...

Objective: The objective of the present research was to formulate and evaluate HPMC K4M, HPMC K100, and Carbopol 940 Mucoadhesive microspheres in combination with sodium alginate for controlling release of Nevirapine. Methods: Nevirapine microspheres were prepared by an Ionotropic gelation method using aluminium sulfate as a cross linking agent. Th...

Biologically synthesized nanoparticles have been widely used in the field of medicine. Especially, silver nanoparticles (Ag NPs) synthesized by the leaf extract lead the biological activity. In the present work, the synthesized Ag NPs by using the leaf extract of Croton sparsiflorus morong Ag NPs were characterized by using UV-Visible (UV-Vis) abso...

The removal of uranium and americium from nitric acid solutions by sulphonated phosphinic acid resin has been investigated. The capacity of the sulphonated resin exceeds the capacities of phosphinic acid resin and commercial cation exchange resin. Other advantages of the sulphonated resin for uranium and americium removal include reduced sensitivit...

Materials and Methods: Microspheres were prepared by ionotropic gelation method using aluminum sulfate as a cross-linking agent. The developed ritonavir microspheres were characterized for micrometrics properties, morphology, drug entrapment efficiency, mucoadhesive property, in vitro drug release and interaction studies (Fourier transforms infrare...

Gadolinium (Gd 3+) is added with nitric acid to moderator heavy water as a neutron poison in nuclear reactors to control reactivity and pH is maintained in the range of 5 to 5.5 to prevent Gd3+ precipitation. Usually ~15 ppm of Gd 3+ is used during actuation of secondary shutdown system and is subsequently removed on ion exchange up to a residual ~...

In the present investigation, we chose the very simple and eco-friendly chemical method for synthesis of zinc oxide nanoparticles from leaf extract of Tamarindus indica (L.) (T. indica) and developed the new green route for synthesis of nanoparticles. Formed product has been studied by UV-vis absorption spectroscopy, Photoluminescence (PL) spectros...

Green synthesis of silver nanoparticles has been achieved using environmentally acceptable plant extract. It is observed that Abutilon indicum leaf extract can reduce silver ions into silver nanoparticles within 15min of reaction time. The formation and stability of the reduced silver nanoparticles in the colloidal solution were monitored by UV-Vis...

A novel green approach for the synthesis and stabilization of silver nanoparticles (AgNPs) using water extract of Leucas martinicensis leaf has been developed. As obtained, the nanoparticles are characterized by UV-visible (UV-Vis), transmission electron microscope (TEM), and X-ray diffraction (XRD). The crystalline nature of the AgNPs is confirmed...

An exact solution of an unsteady flow past a parabolic starting motion of an infinite vertical plate with variable temperature and mass diffusion, in the presence of a homogeneous chemical reaction of first order has been studied. The plate temperature as well as concentration level near the plate are raised linearly with time t. The dimensionless...

Human immunodeficiency virus (HIV) is a retrovirus which causes acquired immuno deficiency syndrome (AIDS), a condition where immune system begins to fail in humans, leading to life-threatening infections. Recent advance in highly active antiretroviral (ARV) agents has led to tremendous reduction of viral load in plasma, progression of infection an...

The decolorization of Reactive blue 28 (RB 28) in aqueous solution has been studied using Fenton (Fe2+/H2O2) and photo-Fenton (Fe2+/H2O2/UV) processes. This investigation indicates that both these methods can remove the color of RB 28. The effects of different system variables namely initial concentration of Fe2+, initial concentration of H2O2, ini...

The aim of the present research was to formulate and evaluate Xanthan gum and Carbopol 940 mucoadhesive microspheres for controlled release of Ritonavir. The mucoadhesive microspheres were formulated by Ionotropic gelation technique, using sodium alginate, Xanthan gum and carbopol as mucoadhesive polymer in various proportions in combination. Furth...

The Flupirtine maleate matrix tablet were prepared using different hydrophilic polymers such as Sodium alginate, Sodium Carboxy methylcellulose , Carbopol 934P in different proportions as release retarding agent to prolong the drug release and to improve the patience compliance. The prepared Flupirtine maleate matrix tablets were subjected to thick...

Biomediated silver nanoparticles were synthesized with the aid of an eco-friendly biomaterial, namely, aqueous Tribulus terrestris extract. Silver nanoparticles were synthesized using a rapid, single step, and completely green biosynthetic method employing aqueous T. terrestris leaf extracts as both the reducing and capping agent. Silver ions were...

Carrier technology offers a promising approach for drug delivery system by coupling the drug to a carrier particle such as microspheres,nanoparticles, niosomes, liposomes etc. which modulates the release characteristics of the drug. Mucoadhesion had been a topic of interest in the design of novel drug delivery system to extend the residence time of...

The present work focuses the use of aqueous extract of Gloriosa superba Linn. (Glory Lily) for producing silver nanoparticles (AgNPs) from silver nitrate aqueous solution. Phytochemical analysis of the extract revealed the presence of alkaloid, amino acids, carbohydrates and proteins in the extract and they serve as effective reducing and capping a...

In this study all the samples like soils, sugarcanes and red rot causing fungi (C. falcatum Went) collected from red rot prone and resistant areas sugarcane fields are analyzed in order to estimate the presence of some important macro and micro elements. This analysis reveals the presence of trace elements like Ca, Na, K, Fe, Mg, Zn, Cu, Mn, Cr, B...

In this study, an attempt has been made to find any possible variation in Physico-Chemical parameters of the soils collected from various sunflower fields (sandy loam & red soil) with root rot diseases in three different manure treatments viz; control (T1), chemical fertilizer (T2) and organic manure (T3). Also the concentrations of four important...

The aim of study was to prepare and characterize mucoadhesive buccal tablets of glipizide using different Mucoadhesive polymers such as Carbopol 940, Sodium alginate and HPMC K15M in combination. Twenty one formulation were developed with different concentration of mucoadhesive polymers in each formulation. The formulated buccal tablets were tested...

Gadolinium is used as neutron poison in Pressurized Heavy Water Reactors (PHWR) at 15 ppm concentration during emergency shut down and at 2 ppm during start up of the reactor. The pHa range of 5–5.5 is recommended based on the acidity requirement for maintaining gadolinium in the solution and to minimize corrosion of moderator system structural mat...

An attempt has been made for the development of Orodispersible tablet of Etoricoxib by direct compression method. Sodium starch glycolate, Crospovidone, Croscarmellose, and Ludiflashwere used as a Superdisintegrants for the formulation. Twenty formulation having Superdisintegrants at different concentration (3, 6, 9, 12 %) level were prepared using...

Permanganate and nitrilotriacetic acid (NTA) based dilute chemical formulations were evaluated for the dissolution of uranium dibutyl phosphate (U-DBP), a compound that deposits over the surfaces of nuclear reprocessing plants and waste storage tanks. A combination of an acidic, oxidizing treatment (nitric acid with permanganate) followed by reduci...

Heavy water is used as coolant in primary heat transport systems of pressurised heavy water reactors. Hydrogen is added at regular intervals to the primary heat transport system to suppress the radiolysis of heavy water. However, the added hydrogen is not fully utilised in the system and finds its way to the heavy water storage tank after passing t...

Antimony(III) adsorption is observed on magnetite (Fe3O4) surface under acidic and reducing condition through surface hydroxyl (SOH) groups bonding on Fe3O4 surface. Desorption of adsorbed Sb(III) is observed from Fe3O4 surface along with iron release in organic acid at 85 °C after 5 h of experiment. Tartaric acid (TA) shows minimum Sb(III) adsorpt...

The data acquisition and processing architecture covers the most demanding applications in continuous patient monitoring for chronic diseases in medical field. The multichannel data acquisition is essential for acquiring and monitoring the various biomedical signals from biomedical sensors or signals from industrial sensors. The problem is that the...

Objective: The Losartan potassium mucoadhesive buccal tablet were prepared using mucoadhesive polymers such as Carbopol 940P, pectin, sodium CMC, Sodium alginate, HPMC K4M, HPMC K15M and HPMC K100M in alone and in combination as release retarding agent to prolong the drug release and to avoid first pass metabolism. Methods: The mucoadhesive buccal...

Objective: The objective of the present study was to prepare mucoadhesive microspheres of Maraviroc by Ionotropic gelation technique by using sodium alginate as mucoadhesive polymer in various proportions for retaining the dosage form remain in vicinity of absorption site for prolonged period of time to treat HIV infection and to avoid first pass m...

Objective: The Losartan potassium floating tablets were prepared using different low density polymers (Gur gum, HPMC different grades, Carbopol, Xanthan gum, Sodium alginate and Gum acacia) in various proportions for prolongation of gastric residence time and to improve the patience compliance. Methods: The Losartan potassium floating tablets were...

Objective: The Glipizide matrix tablet were prepared using different hydrophilic polymers (HPMC different grades and sodium CMC) in various proportions as release retarding agent to prolong the drug release and to improve the patience compliance. Methods: The matrix tablets were prepared by direct compression method. The prepared matrix tablets wer...

The most important adsorbent used in bleaching fats and oils is bleaching earth mixed with activated char coal. After every adsorption cycle, considerable amount of oils and fats were wasted by adsorption. In this study, we suggested an extraction process to recover oil wastes from adsorbent. Three different solvents namely, hexane, benzene and tol...

Objective: To develop and validate simple, sensitive, precise, rapid and cost effective method for determination of Maraviroc in bulk and pharmaceutical formulations as per ICH Guidelines. Methods: A simple double beam UV Spectrophotometric method has been developed and validated with different parameters such as Linearity, Precision, Repeatability...

In this paper, decolourization of reactive red 35 was studied using advanced photo-oxidation process (UV/H2O2). The effect of operating parameters such as solution pH (3-11), H2O2 dosage (10-60 mM), and initial dye concentrations (100-200 mg/L) was studied on % decolourization. The operating parameters were optimized using response surface methodol...

ZnO nanorods prepared through chemical vapor deposition technique are characterized by microscopic and X-ray photoelectron spectroscopy (XPS) techniques to correlate the effects of size on the binding energy of Zn 2p3/2 photoelectrons. A positive shift in Zn 2p3/2-binding energy as compared to that in bulk ZnO is assumed to be the effect of size of...

Ferrites like ZnFe2O4 and NiFe2O4 are heated in-situ in XPS chamber upto 300°C. It has been observed from XPS that ZnFe2O4 undergoes surface enrichment of Fe after 250°C whereas NiFe2O4 does not show such changes. The minute chemical changes are interpreted from the changes in Fe2p and Ni2p peaks due to heating.

Adsorption of nano-ZrO2 (size 8-10 nm) on oxidized stainless steel has been studied. The adsorption behavior was seen to be influenced by composition of the oxidized surface and the surfactant in the aqueous medium. It was observed that the Fe2O3 phase on the surface is most favorable oxide for attracting ZrO2 nano particles in suspension. XPS, XRD...

Carbon steel feeder elbows and feeder piping of the primary coolant system of pressurized heavy water reactors undergo significant wall thinning due to flow accelerated corrosion. The rate of corrosion in certain locations exceeds the design corrosion allowance. Corrosion rate is dependent on several parameters like pH, temperature, dissolved oxyge...

Carbon steel feeders in the primary heat transport system of pressurized heavy water reactors (PHWRs) show significant wall thinning due to flow accelerated corrosion (FAC). This is of great concern, as the wear rate in certain locations exceeds the corrosion allowance by design. This necessitates periodic measurement of wall thickness and in some...

Dilute Chemical Decontamination (DCD) process has been used in several full system and components of nuclear coolant systems to effectively remove the radioactive contaminants that causes radiation field and consequent MANREM problem. The DCD process uses chemicals in very low concentrations (millimolar) and dissolves the oxide film along with the...

Sorption of Sb(III) on carbon steel surface in aqueous medium (pH 2.8) in presence of different oxyanions like molybdate and selenite has been studied. It is observed that the presence of molybdate or selenite in solution reduced Sb(III) adsorption and surface precipitation to a great extent. The solution at different stages of the adsorption exper...

In the moderator system of some nuclear power plants, subsequent to the activation of the safety shutdown system, Gd3+ is removed by ion exchange prior to reactor start-up. During this process, the pH of the system water can get lowered to 3 due to generation of HNO3. Colmonoy-6, which is weld-deposited over valve internals, was found to corrode co...

Coolant systems in nuclear power plants undergo degradation by various corrosion processes. The carbon steel feeder pipes for the primary heat transport system of pressurised heavy water reactors (PHWRs) undergo extensive wall thinning by a degradation process, known as flow accelerated corrosion (FAC). Flow accelerated corrosion occurs under certa...

The aim of study was to prepare and characterize buccoadhesive tablets of Metoprolol tartrate using different Mucoadhesive polymers such as Carbopol 934, Sodium alginate and HPMC K4M in combination. Ten formulations were prepared with varying concentrations of polymers using combination of two polymers in each formulation. Formulations F1 to F5 wer...

Buccoadhesive tablets of piroxicam were prepared by using HPMC K4M and carbopol 934 as mucoadhesive polymers. Ten formulations were developed with varying concentrations of polymers. H1 to H5 formulations were composed of HPMC K4M in ratios of 1:1 to 1:5 whereas in C1 to C5 formulations Carbopol 934 were used in ratios of 1:0.25 to 1:1.5. The formu...