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BRANCHED POLYMERS AND THEIR APPLICATION IN CORROSION INHIBITION FOR MILD STEEL IN 1M H2SO4 MEDIUM
(Oriental Journal of Chemistry, 2014-12-25) Sounthari, P; Kiruthika, A; Saranya, J; Parameswari, K; Chitra, S
The adsorption and corrosion inhibiting effect of branched polymers (BATP, BAAZ, BETP & BEAZ) on mild steel in 1M H2SO4 at 30±1˚C was investigated using gravimetric, electrochemical impedance spectroscopy (EIS), and potentiodynamic polarization techniques. The experimental findings revealed that BATP inhibited the corrosion reaction in the acid environment to greater extend compared to BAAZ, BETP and BEAZ. Impedance results indicate that the polymers were adsorbed on the metal/solution interface, while polarization data showed that the polymers behaved mostly as mixed-type inhibitors. Kinetic parameters (activation energy, pre-exponential factor, enthalpy of activation and entropy of activation) as well as thermodynamic parameters (enthalpy of adsorption, entropy of adsorption and Gibbs free energy) were calculated and discussed. Scanning electron microscopy technique was used to confirm the effectiveness of inhibition of mild steel in sulphuric acid medium.
CATALYTIC ACTIVITY OF TIO2 NANOPARTICLES IN THE SYNTHESIS OF SOME 2,3-DISUBSTITUTED DIHYDROQUINAZOLIN-4(1H)-ONES
(Elsevier, 2014-02) Bharathi, A; Selvaraj Mohana, Roopan; Amir, Kajbafvala; Padmaja, R D; Darsana, M S; Nandhini Kumari, G
Green chemistry is playing an important role for synthesizing organic compounds, due to its eco-friendly nature and low cost. In green chemistry, metal nanoparticles exhibited some useful physical and chemical properties (catalytic activity). Due to its diverse properties, nanoparticles can be utilized as a catalyst in various organic reactions. Recent research has been directed towards the utilization of eco-friendly and bio-friendly plant materials in nanoparticles synthesis. In our present work, TiO2 nanoparticles (TiO2 NPs) were synthesized using Annona squamosa peel extract and their catalytic applications were studied on the 2,3-disubstituted dihydroquinazolin-4(1H)-one synthesis. Synthesized compounds were confirmed using FT-IR, 1H NMR, 13C NMR and GC–MS analyses.
A COMBINED EXPERIMENTAL AND THEORETICAL INVESTIGATION ON PYRAZOLONE DERIVATIVE AS CORROSION INHIBITOR FOR MILD STEEL IN 0.5 M SULPHURIC ACID MEDIA
(Portugaliae Electrochimica Acta, 2014-04-23) Nalini, D; Kohilah, K S; Sowmya, Ramkumar
The inhibition action of the Pyrazolone Derivative (PYR) on the corrosion of mild steel in 0.5 M sulphuric acid was investigated by weight loss, polarization, impedance and SEM. Results obtained revealed that PYR performed excellently as corrosion inhibitor with efficiency of 91% at 11 ppm at 298 K. Its adsorption on mild steel obeys Langmuir and Temkin isotherm. Polarization curves indicate that PYR behaves as mixed type. The value of ∆G° ads indicates the spontaneous physisorption of PYR. The SEM results confirm the presence of a protective surface layer over the mild steel surface. The reactivity of the compound was analysed through theoretical calculation.
CORPORATE LEVERAGE AND ITS IMPACT ON PROFITABILITY AND SHAREHOLDER VALUE CREATION IN THE INDIAN TEXTILE SECTOR
(Indian Journal of Finance, 2014-12) Vijayalakshmi, D; Padmaja, Manoharan
Shareholder value creation has become the trait of corporate dialect. The LPG era has made a drastic change in the financing policies of the corporate firms warranting a redesign in their capital structure. Leverage plays an essential role in framing the capital structure. The focal gain of the insertion of fixed cost funds in the capital structure has a domino effect on higher profits. The textile sector is a capital intensive sector, where a greater emphasis has been given in framing the capital structure. In this backdrop, the present study made an attempt to examine the impact of leverage on profitability and shareholder value creation in the Indian textile sector for the period from 1995-96 to 2009-10. A panel data approach was applied to analyze the data. The study revealed that leverage had a significant influence on profitability, and the sector has to concentrate on enrichment of shareholders' wealth.
EFFECT OF ANNULAR OBSTRUCTION ON TIGHT FOCUSING OF PARTIALLY COHERENT RADIALLY POLARIZED VORTEX BEAM
(Elsevier, 2014-06) Mariyal, C; Suresh, P; Rajesh, K B; Sivasubramonia Pillai, T V; Lavanya, M
Based on vectorial Debye theory, the effect of annular apodization of tightly focused partially coherent radially polarized vortex beams in the focal field of high NA lens is studied. The intensity distribution in the focal region is illustrated by numerical calculations. It is found that the focal depth of the generated focal segment strongly dependent on the source coherence length for unobstructed case and the presence of annular aperture reduces the variation of focal depth with source coherence length.
EFFECT OF MAGNETIC FIELD ON THREE DIMENSIONAL FLUCTUATING COUETTE SLIP FLOW PAST POROUS PLATES
(2014) Sumathi K; Arunachalam T; Radha N
An analysis of the three dimensional flow of an viscous incompressible fluid between two horizontal porous flat plates separated by a finite distance in a slip flow regime is carried out under following conditions: the fluid is electrically conducting, the free stream velocity is uniform, the plate is subjected to a sinusoidal transverse suction velocity distribution and a magnetic field of uniform strength is applied in the direction normal to the plate. The influences of the various parameters on the main flow and cross flow velocity and skin friction are discussed with the help of graphs.
EFFECTS OF SINTERING ON STRUCTURAL AND MAGNETIC PROPERTIES OF CU SUBSTITUTED COBALT–NICKEL MIXED FERRITE NANO PARTICLES
(Elsevier, 2014-08) Balavijayalakshmi, J; Suriyanarayanan, N; Jayaprakash, R
Copper substituted cobalt–nickel mixed ferrite nano particles are synthesized by co-precipitation method and the samples are sintered at 130 °C, 600 °C and 900 °C. The effects of sintering on structural and magnetic properties are studied using XRD analysis and VSM studies. The particle sizes are found to be 12 nm and 32 nm for the samples sintered at 600° and 900 °C respectively and the degree of crystallinity of the sample increases with increasing sintering temperature. The absorption bands shift to lower values on sintering the samples. The saturation magnetization (Ms), remanent magnetization (Mr) and coercivity (Hc) increase on sintering the samples at 600 °C and 900 °C. EDX results confirm the presence of Co, Ni, Cu, Fe and O without any impurities.
EVALUATION OF AGE-STANDARDIZED CANCER BURDEN IN WESTERN TAMIL NADU, INDIA
(Indian Journal of Community Health, 2014-09-20) Janani, Selvaraj; Prashanthi Devi, Marimuthu; Harathi, Parasur Babu
The burden of cancer is growing globally and is one of the top leading causes of death. Information on cancer patterns is essential for effective planning of cancer control interventions. Aims and Objectives:The present cross sectional study aims to explore the patterns and trends of the cancer incidences in the western regions of Tamil Nadu, India including Coimbatore, Erode, Tiruppur,Salem, Namakkal and Nilgiris. Materials andMethods:A sum of 14392 cancer cases were recorded from the hospital based cancer registries of Coimbatore district. The cancer cases were segregated district-wise for specific cancer sites and the age-standardized incident rates were calculated for different age groups. Results:Coimbatore district recorded the highest number of incidences among all districts. Among all age-groups the adults aged 50-74 carry the highest burden of cancer. Among men, head and neck and gastrointestinal cancers are predominant while among women, breast and gynecological cancers are high. The age-standardized incidence rates were found to be higher in Coimbatore and least in Salem. Conclusion:Through this study, it is observed that Coimbatore district is under major threat and needs further investigation of risk factors for implementing optimized treatment and prevention strategies for reducing the adverse effectsof cancer.
EXPERIMENTAL AND QUANTUM CHEMICAL STUDIES ON THE INHIBITION POTENTIAL OF SOME QUINOXALINE DERIVATIVES FOR MILD STEEL IN ACID MEDIA
(Oriental Journal of Chemistry, 2014-11-15) Saranya, J; Sounthari, P; Kiruthika, A; Saranya, G; Yuvarani, S; Parameswari, K; Chitra, S
The inhibition potential of four Quinoxaline derivatives namely 1,4-dihydroquinoxaline-2,3-dione, (3E)-3-hydrazinylidene-3,4-dihydroquinoxalin-2(1H)-one, 1-[(2E)-3-oxo-3,4-dihydroquinoxalin-2(1H)-ylidene]urea and 1-[(2E)-3-oxo-3,4-dihydroquinoxalin-2(1H)-ylidene]thiourea have been investigated against mild steel in 1M H2SO4 solution using conventional weight loss, electrochemical impedance spectroscopy, potentiodynamic polarization and atomic absorption spectroscopy. The percentage inhibition efficiency was found to increase with increase in the inhibitor concentration due to the adsorption of the inhibitor molecules on the metal surface. In addition, it was established that the adsorption follows Langmuir adsorption isotherm. Moreover, some thermodynamic data were calculated and discussed. The density functional theory at the B3LYP/6-311G (d,p) basis set level was performed for two inhibitors namely 1,4-dihydroquinoxaline-2,3-dione and (3E)-3-hydrazinylidene-3,4-dihydroquinoxalin-2(1H)-one. The quantum chemical parameters such as highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO), energy gap (∆E), dipole moment (µ), softness (σ), hardness (η), electronegativity (χ), Mulliken atomic charges, the fraction of electrons transferred from the inhibitor to the metal surface (∆N) and the total energy (TE) have been calculated for these compounds. It was found that theoretical data support the experimental results.
INVESTIGATION ON STRUCTURAL AND MAGNETIC PROPERTIES OF COBALT DOPED MAGNESIUM FERRITE NANOPARTICLES
(International Journal of ChemTech Research, 2014) Balavijayalakshmi, J; Sudha, T; Karthika, K
Nanosized spinel ferrites have attracted considerable attention for their interesting structural, magnetic and electrical properties. The physical and chemical properties of nanomaterials have been enhanced because of their surface-to-volume ratio. To search for new good gas-sensing materials and the new properties of conventional materials has become an active research field. Magnesium ferrite is a most versatile ferrite, due to its high resistivity and low eddy currents. Also the technological importance of cobalt ferrite has motivated several studies on the synthesis as well as the physical properties of this material. Hence an attempt is made to synthesize cobalt doped magnesium ferrite nanoparticles (Mg0.6Co0.4Fe2O4) by co-precipitation method. Magnesium chloride (MgCl 2.6H2O), Cobaltous Chloride (CoCl2.6H2O), anhydrous Ferric Chloride (FeCl3) along with sodium hydroxide (NaOH) is used as raw materials. Magnesium-Cobalt ferrite sample annealed at 600 ○ C are subjected to X-ray diffraction to calculate the average nano-crystalline size using Debye - Scherrer formula and is found to be 2-4 nm. The FT-IR spectrum of the sample is recorded and the characteristic absorption bands are observed at 578 cm -1 and 406 cm -1 corresponding to tetrahedral and octahedral sites respectively. The morphological analysis of the sample is studied using Scanning Electron Microscope (SEM). The magnetic properties of the cobalt doped magnesium ferrite nano particles are studied using Vibrating Sample Magnetometer (VSM) and the magnetic properties are found to be improved due to cobalt doping.
POTENTIAL ECOLOGICAL ASSESSMENT OF SEDIMENT QUALITY AND HEAVY METALS CONTAMINATION IN KURUCHI LAKE, TAMIL NADU, INDIA
(Journal of Materials and Environmental Science, 2014-03-28) Manikandan, R; Kalaichelvi, S; Ezhili, N
Kuruchi Lake is an important freshwater body of Coimbatore City, Tamil Nadu, India. This lake receives municipal wastes and industrial effluents which contain heavy metals. Therefore, the present study was aimed to investigate the status of physicochemical properties and heavy metal levels in surface sediments of Kuruchi Lake. The result of physicochemical parameters such as pH, Electro Conductivity (EC), chloride, calcium, magnesium, phosphate, sulphate, sodium, potassium, total nitrogen, iron, total alkalinity and total organic carbon concentrations were found to be higher in sediment sample of station 4. The heavy metals concentration showed variations with Cd 4-14 mg/kg, Cr 2295-3198 mg/kg, Cu 872-1199 mg/kg, Ni 964-1520 mg/kg, Mn 4996-5820 mg/kg and Pb 999-1489 mg/kg, respectively. The highest concentrations of Cr, Pb, Ni and Cu were found to be higher in station 4, when compared to other study stations. Cd and Mn levels were found within the normal range. The cluster analysis was used for determining the similarity of heavy metals concentrations in different study stations. This study reveals that sediments of Kuruchi Lake were partially polluted with heavy metals. This study provides the baseline data for future sediment quality assessment of this lake and regular monitoring of sediment quality in this lake is highly recommended.
RECT ZONE BASED LOCATION-AIDED ROUTING FOR MOBILE AD HOC AND SENSOR NETWORKS (pdf)
(Asian Network for Scientific Information, 2014) Anna Saro, Vijendran; Viji Gripsy, J
In recent decades, routing in Mobile ad hoc Sensor Network (MASNet) have become an active research area due to its impact in various science and engineering1 applications. The increased demand for energy has become a great concern in industrial market which in turn has led to the development of various energy efficient sensor networks. This research study mainly focuses on secure and energy efficient routing in MASNet. A secure multipath algorithm has been presented in this study which facilitates the nodes in MASNet to carry out on-demand discovery and forming set of paths while identifying a disjointness threshold, denoting the maximal number of nodes shared between any two paths in the set of the k established paths. The proposed Rectangular Zone based Location Specific Routing (RZLSR) approach is energy efficient, adaptive, secure and uses labels to carry the disjointness-threshold between nodes during the route discovery which improves the quality of services. The broadcasting scheme used in this approach is based on RECT which forms an efficient framework for routing data between source and destination. A set of security mechanisms, based on the use of Watchdog and digital signature, are used to protect the route discovery process. The simulation results indicate that the proposed approach provides significant performance with lesser overhead, energy efficient and better network lifetime.
SYNTHESIS AND CHARACTERIZATION OF CUPRIC CHLORIDE DOPED ZINC SULPHIDE NANOPARTICLES
(Sphinx Knowledge House, 2014) Balavijayalakshmi J; Manju S; Lavanya S
In recent years, the research on semiconductor nanoparticles has stimulated much interest because of their unique optical and electrical properties. The nanosized semiconductor crystallites could produce optical properties which are different from bulk materials. Among the semiconductor nanoparticles, Zinc Sulphide is an important II–VI semiconductor material researched extensively because of its wide range of applications in electroluminescence devices, phosphors, light emitting displays and optical sensors. Semiconductor nanoparticles doped with transition metal ions have attracted much attention because of their luminescent properties. Hence an attempt is made to synthesize cupric chloride doped zinc sulphide nanoparticles. The synthesized nanoparticles are subjected to Xray diffraction to calculate the average nano-crystalline size using Debye – Scherrer formula and are found to be 2nm. The morphological analysis of the sample is studied using Scanning Electron Microscope. The UV-Visible spectrophotometer shows the absorption edge of the nanoparticles in range 292 to 261 nm. A FT-IR spectrum confirms the characteristic ZnS vibration peaks.
VISIBLE LIGHT-INDUCED PHOTOCATALYTIC ACTIVITY OF SIO2/CARBON CLUSTER COMPOSITE MATERIALS
(Elsevier, 2014-01) Matsui, H; Santhi, K; Sugiyama, S; Yoshihara, M; Karuppuchamy, S
A convenient – and quick to realize – approach for the synthesis of a novel nano-sized SiO2/carbon cluster composite photocatalyst is suggested. Since, the preparation of visible light sensitive SiO2/carbon cluster composite photocatalyst is hitherto unreported; we performed such investigations to develop a novel catalyst from insulating materials. The synthesized composite indeed show efficient photocatalytic activity by degrading the methylene blue under visible light-irradiation.