Structural and optical properties of vanadium doped SnO₂ nanoparticles with high photocatalytic activities

Reddy, Ch.V.,Babu, B.,Vattikuti, S.V.P.,Ravikumar, R.V.S.S.N.,Shim, J. Elsevier [etc.] 2016 Journal of luminescence Vol.179 No.-

Vanadium (0.01, 0.03 and 0.05mol%) doped SnO<SUB>2</SUB> nanoparticles have been synthesized using combustion synthesis method. The as-prepared nanoparticles were characterized using various measurements such as XRD, SEM with EDS, HRTEM, Raman spectroscopy, optical, PL, XPS and FT-IR techniques. The crystal structure and average particle sizes of the prepared nanoparticles were confirmed from the XRD. The average crystalline particle sizes were decreased by increasing the vanadium dopant concentration. The presence of vanadium as V<SUP>4+</SUP> species in the host lattice was confirmed by X-ray photoelectron spectroscopy. The band gap energies were decreased by increasing dopant concentration. The 0.05mol% doped sample showed higher photocatalytic activity than undoped, V-1 and V-3 in decomposing rhodamine B (RhB) under UV light irradiation. The Raman and IR spectra confirm the fundamental vibration of SnO<SUB>2</SUB> host molecules.

Hydrothermal Synthesis of H2V3O8 Nanobelts from V2O5 Xerogels for Lithium Battery Applications

Sun-Il Mho,Ch.V. Reddy,Youna Kim,In-Hyeong Yeo,Su-Moon Park 한국물리학회 2009 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.54 No.6

Vanadium oxyhydroxide (H2V3O8) nanobelts were synthesized from V2O5 xerogels through a simple hydrothermal process in efforts to obtain nanomaterials for rechargeable Li batteries. Polymers with multidentate oxygen ligands, such as polyethylene glycol or polyethylene oxide, were shown to play a critical role in the formation of H2V3O8 nanobelts during the hydrothermal process. The specific capacity measured during the initial discharge process for the lithium battery with a cathode made of H2V3O8 nanobelts were 292 mAh/g, which stabilized at ca. 261 mAh/g corresponding to two equivalents of Li intercalation/deintercalation into H2V3O8. Lithium batteries made of a vanadium-oxyhydroxide cathode showed better cycle stability than those with a V2O5 cathode.

Synthesis of VO2 (B) nanorods for Li battery application

Ch.V. Subba Reddy,Edwin H. Walker Jr.,S.A. Wicker Sr.,Quinton L. Williams,Rajamohan R. Kalluru 한국물리학회 2009 Current Applied Physics Vol.9 No.6

Vanadium dioxide nanorods were synthesized through a hydrothermal reaction from V2O5 xerogel, poly (vinyl pyrrolidone) (PVP) and lithium perchlorate (LiClO4). The prepared samples were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical discharge–charge cycling in lithium battery. SEM images reveal the nanorods to have dimensions on the order of 1–3 ㎛ in length and 10–50 nm in diameter. The measured initial discharge capacity of the lithium battery with a cathode made of VO2 (B) nanorods was 152 mA h/g. Vanadium dioxide nanorods were synthesized through a hydrothermal reaction from V2O5 xerogel, poly (vinyl pyrrolidone) (PVP) and lithium perchlorate (LiClO4). The prepared samples were characterized by X-ray diffraction, infrared spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and electrochemical discharge–charge cycling in lithium battery. SEM images reveal the nanorods to have dimensions on the order of 1–3 ㎛ in length and 10–50 nm in diameter. The measured initial discharge capacity of the lithium battery with a cathode made of VO2 (B) nanorods was 152 mA h/g.

Simple Preparation of V₂O₅ Nanostructures and Their Characterization

Subba Reddy, Ch. V.,Park, Kyung-Il,Mho, Sun-il,Yeo, In-Hyeong,Park, Su-Moon Korean Chemical Society 2008 Bulletin of the Korean Chemical Society Vol.29 No.10

Simple Preparation of V2O5 Nanostructures and Their Characterization

모선일,Ch. V. Subba Reddy,Kyung-Il Park,여인형,박수문 대한화학회 2008 Bulletin of the Korean Chemical Society Vol.29 No.10

Analgesic and Anti-inflammatory Activity of Carissa carandasLinn fruits and Microstylis wallichii Lindl Tubers

Alok Sharma,G.D. Reddy,Atul Kaushik,K.Shanker,R.K. Tiwari,Alok Mukherjee,Ch.V. Rao 한국생약학회 2007 Natural Product Sciences Vol.13 No.1

ethanolic (50% v/v) extracts of Carissa carandas (fruits) (Apocynaceae) and Microstylis wallichii(tubers) (Orchidaceae) were examined for anti-inflamatory and analgesic activities in experimental animals.Carissa carandas and Microstylis wallichii (50 - 200 mg/kg) caused a dose dependent inhibition of swellingcaused by carrageenin significantly in cotton pellet induced granuloma in rats (P < 0.05 to P < 0.001). There was asignificant increase in the analgesy meter induced pain in rats. The extracts of Carissa carandas and Microstyliswallichii resulted in an inhibition of stretching episodes and percentage protection was 16.05 - 17.58%respectively in acetic acid induced writhing.KeywordsCarissa carandas, Microstylis wallichii, pain, inflamation

Emblica officinalis Protects Against Alcohol-Induced Liver Mitochondrial Dysfunction in Rats

V. Damodara Reddy,P. Padmavathi,N.Ch. Varadacharyulu 한국식품영양과학회 2009 Journal of medicinal food Vol.12 No.2

The protective effect of Emblica officinalis, a commonly used botanical in many Ayurvedic preparations, was investigated for its effects on liver mitochondria of ethanol-administered rats. Oxidative stress and reactive oxygen species-mediated toxicity are considered two of the key underlying mechanisms responsible for alcohol-induced liver injury and mitochondrial dysfunction. Alcohol-administered rats showed a significant elevation of plasma transaminases (aspartate and alanine aminotransferases), alkaline phosphatase, and γ-glutamyl transferase compared to control rats. However, activities of hepatic mitochondrial antioxidant enzymes, viz., superoxide dismutase, glutathione peroxidase, and reduced glutathione, were significantly lower. Chronic alcohol feeding also increased lipid peroxide levels, protein carbonyl content, and overproduction of nitric oxide followed by lowered activities of NADH dehydrogenase, succinate dehydrogenase (SDH), and cytochrome c oxidase and content of cytochromes. Administration of E. officinalis fruit extract (EFE) at a dose of 250 mg/kg of body weight/day to alcoholic rats offers protection by simultaneously lowering the carbonyl content and lipid peroxidation and elevating antioxidant enzyme activities, SDH, NADH dehydrogenase, and cytochrome c oxidase activities, and content of cytochromes in hepatic mitochondria. Our data indicate that EFE administration to chronically alcohol-fed rats offers protection against alcohol-induced alterations. The active tannoid principles and nitric oxide scavenging compounds present in EFE may have contributed to the protection observed.

Mesoporous silica (MCM-41) effect on (PEO+LiAsF6) solid polymer electrolyte

Ch.V. Subba Reddy,G.P. Wu,C.X. Zhao,W. Jin,Q.Y. Zhu,W. Chen,모선일 한국물리학회 2007 Current Applied Physics Vol.7 No.6

Composite polymer electrolyte lms consisting of polyethylene oxide (PEO), LiAsF6 and mesoporous silica (MCM-41) with xedPEO/LiAsF6 = 90/10 but dierent weight percent ratios of MCM-41 were prepared using the solution casting method. The polymer elec-(PEO + LiAsF6) polymer electrolyte facilitates salt dissociation, enhances ion conductivity, and improves miscibility between organicand inorganic moieties. The scanning electron microscopy (SEM) photographs indicates the electrolytes are miscible and homogeneousup to 10 wt.% of MCM-41, and an optimized conductivity is found at this composition (10 wt.%). However, at higher weight ratios(>10 wt.%), the Li/MCM-41-rich domain developed, and the conductivity decreased with increasing mesoporous material. The electro-chemical performance of fabricated electrochemical cells of conguration Li/(PEO + LiAsF6 + MCM-41)/(MoO 3 + C + PTFE) wereinvestigated.

Emblica officinalis Protects Against Alcohol-Induced Liver Mitochondrial Dysfunction in Rats

Reddy, V. Damodara,Padmavathi, P.,Varadacharyulu, N.Ch. The Korean Society of Food Science and Nutrition 2009 Journal of medicinal food Vol.12 No.2

The protective effect of Emblica officinalis, a commonly used botanical in many Ayurvedic preparations, was investigated for its effects on liver mitochondria of ethanol-administered rats. Oxidative stress and reactive oxygen species-mediated toxicity are considered two of the key underlying mechanisms responsible for alcohol-induced liver injury and mitochondrial dysfunction. Alcohol-administered rats showed a significant elevation of plasma transaminases (aspartate and alanine aminotransferases), alkaline phosphatase, and $\gamma$-glutamyl transferase compared to control rats. However, activities of hepatic mitochondrial antioxidant enzymes, viz., superoxide dismutase, glutathione peroxidase, and reduced glutathione, were significantly lower. Chronic alcohol feeding also increased lipid peroxide levels, protein carbonyl content, and overproduction of nitric oxide followed by lowered activities of NADH dehydrogenase, succinate dehydrogenase (SDH), and cytochrome c oxidase and content of cytochromes. Administration of E. officinalis fruit extract (EFE) at a dose of 250 mg/kg of body weight/day to alcoholic rats offers protection by simultaneously lowering the carbonyl content and lipid peroxidation and elevating antioxidant enzyme activities, SDH, NADH dehydrogenase, and cytochrome c oxidase activities, and content of cytochromes in hepatic mitochondria. Our data indicate that EFE administration to chronically alcohol-fed rats offers protection against alcohol-induced alterations. The active tannoid principles and nitric oxide scavenging compounds present in EFE may have contributed to the protection observed.

Influence of calcination temperature on Cd_0.3Co_0.7Fe₂O₄ nanoparticles: Structural, thermal and magnetic properties

Reddy, Ch.Venkata,PrabhakarVattikuti, S.V.,Ravikumar, R.V.S.S.N.,Moon, Sang Jun,Shim, Jaesool Elsevier 2015 Journal of magnetism and magnetic materials Vol.394 No.-

<P><B>Abstract</B></P> <P>Cadmium substituted cobalt ferrite nanoparticles are synthesis using the chemical method. The as-prepared ferrite nanoparticles are calcinated at 300°C and 600°C respectively. The samples are studied using; Powder XRD, SEM with EDX, TEM, FT-IR, TG-DTA and vibrating sample magnetometer (VSM) in order to study the calcination temperature effect on structural, morphological and magnetic properties. The magnetic properties, like saturation magnetization and coercivity increases with increasing the calcination temperature. This enhancement is attributed to the transition from amulti-domain to a single-domain nature. The absorption bands observed at 588cm<SUP>−1</SUP> (<I>ν</I> <SUB>1</SUB>) and 440cm<SUP>−1</SUP> (<I>ν</I> <SUB>2</SUB>) are attributed to the vibrations of tetrahedral and octahedral complexes. The TG-DTA curves reveal the thermal stability of the prepared ferrite nanoparticles. The calcination temperature influences the magnetic properties, surface morphology and crystalline size.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Cd<SUB>0.3</SUB>Co<SUB>0.7</SUB>Fe<SUB>2</SUB>O<SUB>4</SUB> nanoparticles synthesized using the chemical co-precipitation. </LI> <LI> The magnetization, coercivity values increases with increasing the calcination temperature. </LI> <LI> The calcination temperature influences the magnetic properties and crystallite size. </LI> <LI> The FTIR spectra results confirmed the vibrations of tetrahedral and octahedral complexes. </LI> </UL> </P>