Browsing by Author "Nityananda Shetty, A.N."

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2-Mercaptoethylamine as a masking agent for the complexometric determination of palladium(II) in catalysts, alloys and complexes
(Sociedad Chilena de Quimica, 2008) Shetty, P.; Nityananda Shetty, A.N.
A simple, rapid and accurate complexometric method for the determination of palladium in the presence of other metal ions is described, based on the selective masking ability of 2-mercaptoethylamine (MEA) towards Pd(II). Palladium(II) along with other associated metal ions present in a given sample solution is first complexed with an excess of EDTA and the surplus EDTA is titrated with zinc sulphate solution at pH 5-6 (acetic acid-sodium acetate buffer) using xylenol as indicator. A known excess of 0.2% aqueous solution of MEA is then added to displace EDTA from Pd(II)-EDTA complex and swirled well. The released EDTA is again titrated with zinc sulphate solution as before. The method works well in the range 2-20 mg of palladium(II) with the relative error ± 0.27 and the relative standard deviation < 0.35%. The effect of the presence of various diverse ions on the accuracy of the results has been studied. The method has been satisfactorily applied for the determination of palladium in catalysts, alloys and complexes.
3,4-Dimethoxybenzaldehydethiosemicarbazone as corrosion inhibitor for aged 18 Ni 250 grade maraging steel in 0.5 M sulfuric acid
(2011) Poornima, T.; Nayak, J.; Nityananda Shetty, A.N.
The corrosion inhibition of the aged 18 Ni 250 grade maraging steel in 0.5 M sulfuric acid by 3,4-dimethoxybenzaldehydethiosemicarbazone(DMBTSC) has been investigated by potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) techniques. The inhibition efficiency increased with the increase in inhibitor concentration and decreased with the increase in temperature. Polarization curves indicated mixed type inhibition behavior affecting both cathodic and anodic corrosion currents. The thermodynamic parameters of corrosion and adsorption processes were evaluated. The adsorption of DMBTSC on the aged maraging steel surface was found to obey the Langmuir adsorption isotherm model, and the calculated Gibb's free energy values confirm the spontaneous adsorption. The results obtained by the two techniques were in good agreement. © 2010 Springer Science+Business Media B.V.
3-Ethyl-4-amino-5-mercapto-1,2,4-triazole as a corrosion inhibitor for 6061/Al-15 vol% SiCp composite in a sodium hydroxide solution
(2011) Kumari, P.D.R.; Nayak, J.; Nityananda Shetty, A.N.
The inhibition efficiency of 3-ethyl-4-amino-5-mercapto-1,2,4-triazole (EAMT) on the corrosion of 6061/Al-15 vol% SiCp composite in different concentrations of sodium hydroxide solution has been investigated in the 30-50°C temperature range using Tafel and electrochemical impedance spectroscopic techniques. The inhibitor efficiency depends on the concentration of the inhibitor, concentration of the corrosive media, and temperature. The inhibition was assumed to occur through adsorption of the inhibitor molecule on the metal surface. The adsorption of the inhibitor on the metal surface is found to obey Langmuir adsorption isotherm. Thermodynamic parameters for the adsorption processes were determined from the experimental data. Copyright © Taylor &Francis Group, LLC.
3-ethyl-4-amino-5-mercapto-1,2,4-triazole as corrosion inhibitor for 6061-alloy in sodium hydroxide solution
(2011) Reena Kumari, P.D.; Nayak, J.; Nityananda Shetty, A.N.
The inhibition action of 3-ethyl-4-amino-5-mercapto-1,2,4-triazole (EAMT) on the corrosion of 6061-Al alloy in different concentrations of aqueous sodium hydroxide solution has been investigated at different temperatures, using potentiodynamic polarization and electrochemical impedance spectroscopic techniques. The surface morphology of the metal surface was investigated by scanning electron microscopy (SEM). The experimental results showed that the presence of EAMT in sodium hydroxide solution decreases the corrosion rates and the corrosion current densities (icorr), and increases the charge transfer resistance (Rp). It was found that the inhibitor efficiency depends on the concentration of the inhibitor, concentration of the corrosive media and temperature. The inhibition was assumed to occur through adsorption of the inhibitor molecule on the metal surface. The adsorption of the inhibitor on the metal surface is found to obey Langmuir adsorption isotherm. EAMT acts as a mixed inhibitor. Thermodynamic parameters for the adsorption processes were determined from the experimental data. The results obtained from both the techniques are in good agreement.
3-Methyl-4-amino-5-mercapto-1,2,4-triazole as corrosion inhibitor for 6061 Al alloy in 0.5 M sodium hydroxide solution
(Springer New York LLC barbara.b.bertram@gsk.com, 2011) Kumari, P.D.R.; Nayak, J.; Nityananda Shetty, A.N.
3-Methyl-4-amino-5-mercapto-1,2,4-triazole (MAMT) was synthesized, and its inhibition action on the corrosion of 6061 Al alloy in 0.5 M sodium hydroxide was investigated by means of potentiodynamic polarization and electrochemical impedance spectroscopy techniques. The effect of inhibitor concentration, temperature, and concentration of the corrosion medium on the inhibitor action was investigated. The surface morphology of the metal surface was investigated by scanning electron microscopy (SEM). The inhibition efficiency increased with the increase in the concentration of the inhibitor, but decreased with the increase in temperature. Both thermodynamic and kinetic parameters were calculated and discussed. The adsorption of MAMT on the base alloy was found to be through physisorption, obeying Langmuir's adsorption isotherm. The results obtained from both the techniques were in good agreement with each other. © 2011 ACA and OCCA.
3-Methyl-4-amino-5-mercapto-1,2,4-triazole as corrosion inhibitor for 6061/Al-15 (vol-%) sic(p) composite in 0.5M sodium hydroxide solution
(2011) Kumari, P.D.R.; Nayak, J.; Nityananda Shetty, A.N.
3-Methyl-4-amino-5-mercapto-1,2,4-triazole (MAMT) was investigated for its inhibition action on the corrosion of 6061/Al - 15 (vol-%) SiC(p) composite in 0.5M sodium hydroxide solution at different temperatures by potentiodynamic polarization and electrochemical impedance spectroscopic techniques. The effect of inhibitor concentration, temperature and concentration of the corrosion medium on the inhibitor action was investigated. The inhibition efficiency increased with the increase in the concentration of inhibitor but decreased with the increase in temperature. Both thermodynamic and activation parameters were calculated and discussed. The adsorption of MAMT on the composite was found to be through physisorption obeying Langmuir's adsorption isotherm.
4-(N,N-diethylamino) benzaldehyde thiosemicarbazone in the spectrophotometric determination of palladium
(2007) Parameshwara, P.; Karthikeyan, J.; Nityananda Shetty, A.N.; Shetty, P.
4-(N,N-diethylamino)benzaldehyde thiosemicarbazone(DEABT) is proposed as a sensitive and selective analytical reagent for the spectrophotometric determination of palladium(II). The reagent reacts with palladium (II) in a potassium hydrogen phthalate-hydrochloric acid buffer of pH 3.0, to form a yellow complex. Beer's law is obeyed in the concentration range up to 3.60 ?gmL-1. The optimum concentration range for minimum photometric error as determined by Ringbom plot method is 0.36-3.24 ?g mL-1. The yellow Pd(II)-DEABT complex shows a maximum absorbance at 408 nm, with molar absorptivity of 3.33 × 104 dm3 mol-1 cm-1 and Sandell's sensitivity of the complex from Beer's data, for D=0.001, is 0.0032 ?g cm-2. The composition of the Pd(II)-DEABT complex is found to be 1:2 (M:L). The interference of various cations and anions in the method were studied. The proposed method was successfully used for the determination of Pd(II) in alloys, catalysts, complexes and model mixtures with a fair degree of accuracy.
A complexometric method for the determination of cadmium(II) in presence of other metal ions is described based on the selective masking ability of 2-mercaptoethanol towards cadmium(II). Cadmium and other ions in a given sample solution are initially complexed with excess of EDTA and the surplus EDTA is titrated with lead nitrate solution at pH 5.0-6.0 (hexamethylentetramine), using xylenol orange as indicator. A known excess of 2-mercaptoethanol solution (10% alcoholic) is then added, the mixture is shaken well and the released EDTA from the Cd-EDTA complex is titrated against standard lead nitrate solution. The interferences of various ions are studied and the method is applied to the determination of cadmium in its complexes. Reproducible and accurate results are obtained for 3.5-25 mg of Cd with relative errors ? 0.65% and standard deviations ? 0.06 mg.
(Springer New York, Complexometric Determination of Cadmium Using 2-Mercaptoethanol as Masking Reagent) Muralidhara Rao, B.; Nityananda Shetty, A.N.
1998
A complexometric method for the determination of mercury(II) in presence of other metal ions is described based on the selective masking action of 1-propane thiol towards mercury(II). Mercury(II) present in a given sample solution is first complexed with an excess of EDTA and the unreacted EDTA is titrated against lead nitrate solution at pH 5-6 (hexamine buffer) using xylenol orange as the indicator. A 0.8% aqueous solution of 1-propane thiol is then added to displace EDTA from the Hg(II)-EDTA complex. The released EDTA is titrated with standard lead nitrate solution as before. Reproducible and accurate results are obtained for 4-85 mg of mercury(II), with relative error less than ±0.23% and coefficient of variation not more than ±0.41%. The effects of various ions were studied. The method is used for the analysis of mercury(II) in its synthetic alloy mixtures and also in complexes.
(Indirect complexometric determination of mercury(II) using 1-propane thiol (PT) as a selective masking agent) Parameshwara, P.; Karthikeyan, J.; Nityananda Shetty, A.N.; Shetty, P.
2005
A complexometric method for the determination of mercury(II) in presence of other metal ions is described based on the selective masking action of 2-mercaptopropionic acid towards mercury(II). Mercury(II) present in a given sample solution is first complexed with an excess of EDTA and the unreacted EDTA is titrated against zinc sulphate solution at pH 5-6 (hexamine buffer) using xylenol orange as the indicator. A 0.5% aqueous solution of 2-mercaptopropionic acid is then added to displace EDTA from the Hg(II)-EDTA complex. The released EDTA is estimated. Reproducible and accurate results are obtained for 4-88 mg of mercury(II) with relative error less than ± 0.46% and coefficient of variation not more than 0.34%. The effects of various ions were studied. The method is used for the analysis of mercury in its synthetic alloy mixtures and also in complexes.
(Indirect complexometric determination of mercury(II) using 2-mercaptopropionic acid (2-MPA) as a selective masking agent) Karthikeyan, J.; Parameshwara, P.; Nityananda Shetty, A.N.; Shetty, P.
2005
A complexometric method for the determination of mercury(II) in presence of other metal ions, based on the selective masking action of ethanethiol towards mercury(II) is described. Mercury(II) present in a given sample solution is first complexed with an excess of EDTA and the unreacted EDTA is titrated against zinc sulphate solution at pH 5-6 (hexamine buffer) using xylenol orange as the indicator. An excess of a 0.3 % solution of ethanethiol is then added to displace EDTA from the Hg(II)-EDTA complex. The released EDTA is titrated with a standard zinc sulphate solution. Reproducible and accurate results are obtained for 4-85 mg of mercury(II) with a relative error of less than ± 0.46 % and coefficient of variation of not more than 0.47 %. The effects of the presence of various ions were studied. The method can be used for the analysis of mercury in its synthetic alloy mixtures and also in complexes.
(Serbian Chemical Society, Indirect complexometric determination of mercury(II) in synthetic alloys and complexes using ethanethiol as a selective masking agent) Karthikeyan, J.; Parameshwara, P.; Nityananda Shetty, A.N.; Shetty, P.
2006
A green approach to energy storage properties of polyaniline
(Springer, 2024) Viswanathan, A.; Nityananda Shetty, A.N.
The green energy storage of polyaniline, without major wastages excreted into the environment is effectively demonstrated by using the polyaniline as supercapacitor electrode and the by-product obtained during the synthesis of polyaniline as its electrolyte. This green approach to the energy storage properties of sulphuric acid doped polyaniline (H-PANI) exhibited a substantial improvement in its energy storage, compared to the conventional approach of using an ionically conducting liquid as electrolyte like 1 M H2SO4 (SA), separately. The amelioration of 40.44% was achieved when the by-product obtained as supernatant liquid (SL) was used as electrolyte compared to SA. The H-PANI provided a specific capacity (Q) of 146.4 C g?1, a specific energy (E) of 24.40 W h kg?1 and a specific power (P) of 1.200 kW kg?1 at 1 A g?1 in the presence of SA. The Q of 205.6 C g?1, E of 34.26 W h kg?1 (similar range of E of Pb-acid batteries), P of 1.200 kW kg?1 were achieved in the presence of SL at 1 A g?1 and a high rate capability of 29.18% retention of initial Q up to 25 A g?1 was also achieved. This approach is useful to harvest high energy characters from PANI. © Indian Academy of Sciences 2024.
A rapid extractive spectrophotometric determination of copper(II) in environmental samples, alloys, complexes and pharmaceutical samples using 4-N,N(dimethyl)amino]benzaldehyde thiosemicarbazone
(2011) Karthikeyan, J.; Naik, P.P.; Nityananda Shetty, A.N.
4-[N,N-(Dimethyl)amino]benzaldehyde thiosemicarbazone (DMABT) is proposed as an analytical reagent for the extractive spectrophotometric determination of copper(II). DMABT forms yellow colored complex with copper(II) in the pH range 4.4-5.4. Beer's law is obeyed in the concentration range up to 4.7 ?g mL -1. The optimum concentration range for minimum photometric error as determined by Ringbom plot method is 1.2-3.8 ?g mL-1. The yellowish Cu(II)-DMABT complex shows a maximum absorbance at 420 nm, with molar absorptivity of 1.72 × 104dm3 mol-1 cm-1 and Sandell's sensitivity of the complex obtained from Beer's data is 0.0036 ?g cm-2. The composition of the Cu(II)-DMABT complex is found to be 1:2 (M/L). The interference of various cations and anions in the method were studied. Thus the method can be employed for the determination of trace amount of copper(II) in water, alloys and other natural samples of significant importance. © 2010 Springer Science+Business Media B.V.
A selective complexometric method is described for the determination of mercury(II) using sodium metabisulphite as a masking reagent. An excess of EDTA is added to mercury(II) solution containing associated diverse metal ions and the surplus EDTA is back titrated at pH 5-6 (hexamine buffer) with standard zinc sulphate solution using xylenol orange as indicator. An aqueous solution of sodium metabisulphite is then added to displace EDTA selectively from Hg-EDTA complex and the released EDTA is then titrated against the same standard zinc sulphate solution. Reproducible and accurate results are obtained in the range 4-100 mg of mercury with a relative error ? 0.26% and coefficient of variation ?0.40%. The method is useful for the analysis of mercury in complexes and alloy samples.
(Complexometric method for the determination of mercury using sodium metabisulphite as selective masking reagent) Shetty, P.; Nityananda Shetty, A.N.
2004
A simple and rapid complexometric determination of thallium(III) using mercaptoethane as demasking agent
(2006) Shetty, P.; Nityananda Shetty, A.N.
A simple, rapid and selective complexometric method is proposed for the determination of thallium(III), using mercaptoethane(EtSH) as demasking agent. The sample solution containing Tl(III) is first complexed with excess EDTA and the surplus EDTA is removed by titration at pH 5-6 with zinc sulphate solution using xylenol orange as indicator. EtSH solution is then added to displace EDTA selectively from Tl-EDTA complex. Thallium is determined indirectly by titration of released EDTA with zinc sulphate solution. Reproducible and accurate results are obtained in the concentration range 4-80 mg of thallium with a relative error ? ±0.6% and relative standard deviation ?0.7%. The method is successfully applied to the determination of Tl(III) in its synthetic alloy compositions and complexes, and waste-water samples.
A simple and selective complexometric method for the determination of thallium in presence of other metal ions is proposed based on the selective masking ability of ethanethiol towards thallium(III). Thallium present in a given sample solution is first complexed with a known excess of EDTA and the surplus EDTA is titrated with standard zinc sulphate solution at pH 5-6(hexamine) using xylenol orange as the indicator. A 0.3% aqueous solution of ethanethiol is then added to displace EDTA from the Tl(III)-EDTA complex. The released EDTA is titrated with standard zinc sulphate solution as before. Reproducible and accurate results are obtained for 3.70 mg to 74.07 mg of Tl (III) with relative error less than ±0.44% and coefficient of variation not more than 0.27%. The interference of various ions was studied and the method was used for the analysis of thallium in its synthetic alloy mixtures and also in complexes. ©2006 Sociedade Brasileira de Química.
(Sociedade Brasileira de Quimica, Complexometric determination of thallium(III) using ethanethiol as a selective masking agent) Karthikeyan, J.; Parameshwara, P.; Nityananda Shetty, A.N.; Shetty, P.
2006
A simple and selective complexometric method for the determination of thallium(III) is proposed by using thioglycolic acid as a masking agent. In the presence of diverse metal ions thallium(III) is complexed with excess EDTA and the surplus EDTA is back titrated (pH 5 - 6 , hexamine) with standard zinc sulphate solution using xylenol orange indicator. A freshly prepared 1% aqueous solution of thioglycolic acid is then added to displace EDTA from Tl(III)-EDTA complex and the released EDTA is titrated with standard zinc sulphate solution. The results for the determination of 4 - 87 mg of thallium are obtained with a relative error of 0.3% and coefficient of variation 0.46%. The effect of diverse ions are studied. The method is applied to the determination of thallium in its complexes and synthetic mixtures.
(Indirect complexometric determination of thallium(III) using thioglycolic acid as masking agent) Shetty, P.; Nityananda Shetty, A.N.; Gadag, R.V.
2000
A simple solution phase synthesis of copper nanofluid using single-step glucose reduction method
(2013) Shenoy, U.; Nityananda Shetty, A.N.
Synthesis of copper nanofluid by a one-step method involving the reduction of copper sulfate by glucose in the presence of sodium lauryl sulfate has been reported. The method relies on the simultaneous formation and dispersion of the copper nanoparticles in the base fluid. Effects of various reaction parameters on the size and reaction rate are investigated using different techniques. Thermal conductivity and viscosity measurements of the nanofluid are also carried out. Sedimentation measurement reveals that the fluid is stable for a minimum period of six weeks. The reported method is found to be rapid, simplistic, and cost effective. © 2013 Taylor & Francis Group, LLC.
A simple, rapid and accurate complexometric method for the determination of palladium(II) is proposed, based on the selective demasking property of 2-mercapto propionyl glycine (MPGH2) towards palladium(II). In the presence of diverse metal ions, palladium(II) is complexed with excess of EDTA and the surplus EDTA is back titrated at pH 5-5.5 (acetic acid-acetate buffer) with standard zinc sulphate solution using xylenol orange as indicator. An excess of a 0.2% aqueous solution of MPGH2 is then added to displace EDTA from Pd(II)-EDTA complex. The released EDTA is titrated with the same standard zinc sulphate solution as before. Reproducible and accurate results are obtained in the concentration range 2-22 mg of palladium with relative error of ±0.36% and coefficient of variation (n=6) not exceeding 0.31%. The effect of diverse ions are studied. The method is used for the determination of palladium in its complexes, catalysts and synthetic alloy mixtures.
(Complexometric determination of palladium(II) using 2-mercapto propionyl glycine as demasking agent) Shetty, P.; Nityananda Shetty, A.N.; Gadag, R.V.
2002
A simple, rapid and accurate complexometric method for the determination of palladium(II) is proposed, based on the selective masking property of thioacetamide towards palladium(II). In the presence of diverse metal ions, palladium(II) is complexed with excess of EDTA and the surplus EDTA is back titrated at pH 5-5.5(acetic acid-sodium acetate buffer) with standard lead nitrate solution using xylenol orange as indicator. An excess of a 0.5% aqueous solution of thioacetamide is then added to displace EDTA from Pd(II)-EDTA complex. The released EDTA is titrated with the same standard lead nitrate solution as before. Reproducible and accurate results are obtained in the concentration range 0.5mg-17.80mg of palladium with relative error of ±0.16% and coefficient of variation not exceeding 0.26%. The effect of diverse ions is studied. The method is used for the determination of palladium in its complexes, catalysts and synthetic alloy mixtures.
(Complexometric determination of palladium(II) using thioacetamide as a selective masking agent) Parameshwara, P.; Karthikeyan, J.; Nityananda Shetty, A.N.; Shetty, P.
2006