Faculty Publications

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    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
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    Studies on the removal of Pb(II) from wastewater by activated carbon developed from Tamarind wood activated with sulphuric acid
    (2008) Singh, C.K.; Sahu, J.N.; Mahalik, K.K.; Mohanty, C.R.; Mohan, B.R.; Meikap, B.C.
    The low-cost activated carbon were prepared from Tamarind wood material by chemical activation with sulphuric acid for the adsorption of Pb(II) from dilute aqueous solution. The activated carbon developed shows substantial capacity to adsorb Pb(II) from dilute aqueous solutions. The parameters studied include physical and chemical properties of adsorbent, pH, adsorbent dose, contact time and initial concentrations. The kinetic data were best fitted to the Lagergren pseudo-first-order and pseudo-second order models. The isotherm equilibrium data were well fitted by the Langmuir and Freundlich models. The maximum removal of lead(II) was obtained 97.95% (experimental) and 134.22 mg/g (from Langmuir isotherm model) at initial concentration 40 mg/l, adsorbent dose 3 g/l and pH 6.5. This high uptake showed Tamarind wood activated carbon as among the best adsorbents for Pb(II). © 2007 Elsevier B.V. All rights reserved.
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    Spectrophotometric determination of platinum(IV) in alloys, complexes, environmental, and pharmaceutical samples using 4-[N,N-(diethyl)amino] benzaldehyde thiosemicarbazone
    (2010) Naik, P.P.; Karthikeyan, J.; Nityananda Shetty, A.N.
    4-[N,N-(Diethyl)amino] benzaldehyde thiosemicarbazone (DEABT) is proposed as an analytical reagent for the spectrophotometric determination of platinum(IV). The DEABT forms 1:2 yellow complex with Pt(IV), which is sparingly soluble in water and completely soluble in water-ethanol-DMF medium. The Pt(IV)-DEABT complex shows maximum absorbance at 405 nm. Beer's law is valid up to 7.80 ?g cm-3, and optimum concentration range for the determination of platinum(IV) is 0.48-7.02 ?g cm-3. The molar absorptivity and Sandell's sensitivity of the method are found to be 1.755 × 104 dm3 mol-1 cm-1 and 0.0012 ?g cm-2, respectively. The relative error and coefficient of variation (n=6) for the method does not exceed ±0.43% and 0.35%, respectively. Since the method tolerates a number of metal ions commonly associated with platinum, it can be employed for the determination of platinum in environmental samples, pharmaceutical samples, alloys, catalysts, and complexes. The method is rapid as the Pt(IV)-DEABT complex is soluble in water-ethanol-DMF medium and not requiring any time consuming extraction method for the complex. © 2010 Springer Science+Business Media B.V.
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    Degradation of paracetamol in aqueous solution by Fenton Oxidation and photo-Fenton Oxidation processes using iron from Laterite soil as catalyst
    (2011) Manu, B.; Mahamood
    For the treatment of paracetamol in water, the photo-Fenton Oxidation process and Classic Fenton oxidation process have been demonstrated and found effective. An iron catalyst extracted from lateritic soil is used to exhibit the degradation and mineralization of paracetamol. Paracetamol reduction and chemical oxygen demand (COD) removal are measured as the objective functions to be maximized. The experimental conditions of the degradation of paracetamol are optimized by Fenton process. the optimum conditions observed for 10 mg/L initial paracetamol concentration are influent pH 3, initial H 2O 2 dosage 30 mg/L, [paracetamol]/[H 2O 2] ratio 1:3 (w/w) and [H 2O 2] / [Laterite iron] ratio 30:0.75 (w/w). At the optimum conditions, for 10 mg/L of initial paracetamol concentration, 76% paracetamol reduction and 69% COD removal by Fenton oxidation and 79% paracetamol reduction and 77% COD removal by UV-C Fenton process are observed in 120 minutes reaction time. At the above optimum conditions, HPLC analysis has demonstrated 100% removal of paracetamol for Fenton oxidation process in 240 minutes and for UV-C photo- Fenton process in 120 minutes. The methods are effective and they may be used in the paracetamol industry. © 2011 CAFET-INNOVA TECHNICAL SOCIETY.
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    Partitioning studies of ?-lactalbumin in environmental friendly poly (ethylene glycol) - Citrate salt aqueous two phase systems
    (2013) Kalaivani, S.; Iyyaswami, I.
    Aqueous two-phase systems (ATPS) formed by polymer and salt have been utilized to enrich the desired biomolecule into one of the phase with higher yield and purity. The eco-friendly, biodegradable poly ethylene glycol (PEG) and different citrate salts were chosen as ATPS phase components to investigate the partitioning behavior of ?-lactalbumin (?-La). System factors and process parameters such as type and concentration of salt, molecular weight and concentration of PEG, pH, temperature and the effect of additives were studied and the results are discussed in detail. PEG 1000-tri-potassium citrate system yields high partition coefficient of 20 with a better yield of 98 % in the top phase. The addition of NaCl as an additive and acidic pH lowers the yield of ?-La in the top phase. Influence of phase volume ratio (V r) on partitioning was studied and found that the partition coefficient remains almost constant along the tie line. High yield was achieved at a V r of 3.5 at the tie line length of 50.63 (%, w/w). © 2013 Springer-Verlag Berlin Heidelberg.
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    Extraction, characterization and biological studies of phytochemicals from Mammea suriga
    (Xi'an Jiaotong University, 2015) Poojary, M.M.; Vishnumurthy, K.A.; Vasudeva Adhikari, A.V.
    Abstract The present work involves extraction of phytochemicals from the root bark of a well-known Indian traditional medicinal plant, viz. Mammea suriga, with various solvents and evaluation of their in vitro antimicrobial and antioxidant activities using standard methods. The phytochemical analysis indicates the presence of some interesting secondary metabolites like flavonoids, cardiac glycosides, alkaloids, saponins and tannins in the extracts. Also, the solvent extracts displayed promising antimicrobial activity against Staphylococcus aureus, Bacillus subtilis and Cryptococcus neoformans with inhibition zone in a range of 20-33 mm. Further, results of their antioxidant screening revealed that aqueous extract (with IC50 values of 111.51±1.03 and 31.05±0.92 ?g/mL in total reducing power assay and DPHH radical scavenging assay, respectively) and ethanolic extract (with IC50 values of 128.00±1.01 and 33.25±0.89 ?g/mL in total reducing power assay and DPHH radical scavenging assay, respectively) were better antioxidants than standard ascorbic acid. Interestingly, FT-IR analysis of each extract established the presence of various biologically active functional groups in it. © 2015 Xi'an Jiaotong University.
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    Studies on the Site-specific PEGylation Induced Interferences Instigated in Uricase Quantification Using the Bradford Method
    (Springer Netherlands, 2016) Nanda, P.; JagadeeshBabu, P.E.
    Uricase from Bacillus fastidiosus was site-specifically PEGylated using methoxypolyethyleneglycol-maleimide (mPEG-mal) of different molecular weights (750 Da, 5 kDa, 10 kDa) via Thiol PEGylation strategy. The obtained monoPEGylated uricase conjugates were characterized using sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and the molecular weight of single subunit of the conjugate was found to be 42.6, 48.1 and 56.3 kDa with respect to different molecular weights of m-PEG-mal. The influence of PEGylation on the quantification of uricase using protein quantification techniques like Bradford assay, RP-HPLC detection and Dumbroff method has been evaluated. A gradual decline in the absorbance value was observed with the advancement of the PEGylation reaction, indicating an interferences in the protein quantification due to PEGylation. The extent of interference highly dependence on mPEG-mal concentration and its chain length. The present study indicates that the quantification of PEGylation induced interferences caused in protein measured ought to be prudently measured at every discrete step of the PEGylation process. © 2016, Springer Science+Business Media New York.
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    Hydrous Cerium Oxide Nanoparticles Impregnated Enteromorpha sp. for the Removal of Hexavalent Chromium from Aqueous Solutions
    (American Society of Civil Engineers (ASCE) onlinejls@asce.org, 2016) Selvasembian, S.; Selvaraju, N.; Raj Mohan, B.; Muhammed Anzil, P.K.; Amith, K.D.; Ushakumary, E.R.
    A novel nanobiocomposite, hydrous cerium oxide nanoparticles impregnated Enteromorpha sp. (HCONIE) was used effectively for the adsorption of Cr(VI) from aqueous solutions. The chemical and structural characteristics of the nanobiocomposite were investigated using Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) analysis. Adsorption studies were determined as a function of pH, contact time, initial concentration of Cr(VI), HCONIE dose, and temperature. The equilibrium adsorption data were modeled using two parameter isotherms, including Langmuir, Freundlich, Dubinin-Radushkevich (D-R), Temkin, Jovanovic, Halsey, and Harkin-Jura. Adsorption data were well described by the Freundlich and Halsey isotherm. The kinetics data were analyzed using adsorption kinetic models like the pseudo-first-order, pseudo-second-order and intraparticle diffusion equation. Kinetic data showed good agreement with the pseudo-second-order kinetic model. The obtained thermodynamic parameters showed that the adsorption of Cr(VI) onto the HCONIE was exothermic in nature. The presence of foreign ions showed a decreased effect on the adsorption capacity of HCONIE towards Cr(VI) removal. The desorption study was carried out with 0.1 and 0.5 M of three different desorbing agents. The study suggests that HCONIE nanobiocomposite could be used for the removal of Cr(VI) from aqueous solution. © 2015 American Society of Civil Engineers.
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    Surface characterization and methylene blue adsorption studies on a mesoporous adsorbent from chemically modified Areca triandra palm shell
    (Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2016) Thangappan, H.; Valiya Parambathu, A.; Joseph, S.
    Activated carbon was prepared from Areca triandra palm shell (ATPS) by chemical activation with sulphuric acid, and its application for the adsorption of methylene blue dye from aqueous solution was investigated. FTIR spectral analysis and Boehm titrations were used to examine the oxygenated surface functional groups tailored to adsorb cationic toxins from solutions, point of zero charge estimated the surface charge for electronic affinity induced by chemical treatment. BET and SEM analyses revealed mesoporous adsorbent with homogenous pores and the BET surface area is 27.3 m2/g. The influence of process parameters, namely contact time, initial concentration, adsorbent dosage and pH was evaluated by batch adsorption studies. The equilibrium adsorption data were fitted with three isotherm models, among them Langmuir isotherm model best fitted and the maximum adsorption capacity of methylene blue was found to be 312.5 mg/g. The kinetic adsorption data best fitted with pseudo-second-order kinetics out of three kinetic models tested. The thermodynamic parameters, Gibb’s free energy change (?G°), enthalpy change (?H°) and entropy change (?S°) ascertain that the adsorption is a spontaneous endothermic process with high affinity between surface and dye. The results of the present study suggest that the adsorbent prepared from ATPS is a potential adsorbent for the treatment of effluent containing cationic dyes. © 2015 Balaban Desalination Publications. All rights reserved.
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    Influence of palm oil fuel ash, an agro-industry waste on the ultrafiltration performance of cellulose acetate butyrate membrane
    (Taylor and Francis Inc. 325 Chestnut St, Suite 800 Philadelphia PA 19106, 2016) Shenvi, S.S.; Isloor, A.M.; Ahmad, A.L.; Garudachari, B.; A.F., A.F.
    Palm oil fuel ash (POFA), which is produced as waste during production of palm oil, was used as an alternative additive to prepare cellulose acetate butyrate (CAB) composite ultrafiltration membrane. Acid-activated-milled POFA was characterized by Brunauere–Emmette–Teller (BET) surface area analysis and infrared spectroscopy (IR). The effect of incorporation of POFA in CAB matrix was analyzed by contact angle, water uptake, and porosity studies. The studies revealed an enhancement in the hydrophilic nature of the composite membranes upon addition of POFA. The change in the morphology of the membranes was recorded by means of scanning electron microscopy (SEM) which revealed the changing asymmetric structure of the membrane. Pure water flux and antifouling studies indicated that the membranes exhibited enhanced flux recovery ratio, which was maximum for CAB 2 (87.6%) containing 2 wt.% of POFA. The adsorption property of POFA in addition to CAB/POFA network helped in the humic acid removal from aqueous solution up to 86% for CAB 2.5 membrane. © 2016 Balaban Desalination Publications. All rights reserved.