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Binitha N.N.,Sree Neelakanta Government Sanskrit College | Binitha N.N.,National University of Malaysia | Yaakob Z.,National University of Malaysia | Resmi R.,Sree Neelakanta Government Sanskrit College
Central European Journal of Chemistry | Year: 2010

Synthesis of various zirconium doped titania based photocatalysts were carried out by adapting different synthetic strategies. Doping is done on commercially available anatase titania, sol-gel titania and template mediated sol gel titania. A comparative study of the various prepared photocataysts was done using physico-chemical characterization techniques such as X-ray diffraction (XRD), surface area- pore volume measurements, UV-VIS Diffuse reflectance spectra (DRS), elemental analysis (XRF) and transmission electron microscopic (TEM) studies. The effect of zirconium and preparation methods on the photocatalytic degradation of methylorange is studied extensively. Both the surface properties and photo activity of zirconium doped titania were found to have a great dependence on the preparation methods. Among the different photocatalytic systems, the catalyst prepared by doping in the presence of urea template was found to produce a maximum photodegradation of 97.5%. © Versita Warsaw and Springer-Verlag Berlin Heidelberg.


Pudukudy M.,National University of Malaysia | Pudukudy M.,Sree Neelakanta Government Sanskrit College | Yaakob Z.,National University of Malaysia | Narayanan B.,Sree Neelakanta Government Sanskrit College | And 2 more authors.
International Journal of Hydrogen Energy | Year: 2012

There are several reports currently on the hydrogen production from water employing aluminium powders, alloys and waste aluminium materials. However, mostly it is done in the presence of corrosive sodium hydroxide. Present study reports the production of hydrogen from sea water, which is the most dominant source of crude water. Instead of sodium hydroxide, cheap calcium oxide is employed with waste aluminium for the production of hydrogen and it is found that the minerals present in sea water and the use of NaCl as an additive enhances the rate of hydrogen production. It is also observed that change in the reaction conditions has a marked effect on the induction period for H 2 evolution. Additionally, the solid obtained after completion of H2 production shows good efficiency in water splitting reaction. Copyright © 2012, Hydrogen Energy Publications, LLC. Published by Elsevier Ltd. All rights reserved.


Bshish A.,National University of Malaysia | Yaakob Z.,National University of Malaysia | Narayanan B.,National University of Malaysia | Narayanan B.,Sree Neelakanta Government Sanskrit College | And 2 more authors.
Chemical Papers | Year: 2011

Production of hydrogen by steam-reforming of ethanol has been performed using different catalytic systems. The present review focuses on various catalyst systems used for this purpose. The activity of catalysts depends on several factors such as the nature of the active metal catalyst and the catalyst support, the precursor used, the method adopted for catalyst preparation, and the presence of promoters as well as reaction conditions like the water-to-ethanol molar ratio, temperature, and space velocity. Among the active metals used to date for hydrogen production from ethanol, promoted-Ni is found to be a suitable choice in terms of the activity of the resulting catalyst. Cu is the most commonly used promoter with nickel-based catalysts to overcome the inactivity of nickel in the water-gas shift reaction. γ-Al 2O3 support has been preferred by many researchers because of its ability to withstand reaction conditions. However, γ-Al 2O3, being acidic, possesses the disadvantage of favouring ethanol dehydration to ethylene which is considered to be a source of carbon deposit found on the catalyst. To overcome this difficulty and to obtain the long-term catalyst stability, basic oxide supports such as CeO2, MgO, La2O3, etc. are mixed with alumina which neutralises the acidic sites. Most of the catalysts which can provide higher ethanol conversion and hydrogen selectivity were prepared by a combination of impregnation method and sol-gel method. High temperature and high water-to-ethanol molar ratio are two important factors in increasing the ethanol conversion and hydrogen selectivity, whereas an increase in pressure can adversely affect hydrogen production. © 2011 Institute of Chemistry, Slovak Academy of Sciences.


Pudukudy M.,National University of Malaysia | Pudukudy M.,Sree Neelakanta Government Sanskrit College | Yaakob Z.,National University of Malaysia | Mohammad M.,National University of Malaysia | And 2 more authors.
Renewable and Sustainable Energy Reviews | Year: 2014

Renewable alternative energy sources are getting more attention due to the depleting nature of non-renewable fossil fuels. Increasing global warming, caused by the combustion of fossil fuels, triggered the intense research in finding out better energy options with low emission. Among the potential energy options, hydrogen is a clean fuel candidate as it simply produces water as byproducts when burning. Hydrogen can be generated from different renewable sources and Asia is one of the continents which is rich in renewable energy resources. The resources, safety parameters, public acceptability, and proper government incentives are the major factors affecting the implementation of hydrogen as an economical energy source in Asian countries. The present review deals with the necessity of employing hydrogen as an alternative fuel, its production paths, storage issues, transportation and the available sources. Special emphasis has been given to the discussion of renewable hydrogen economy in some Asian countries like, Japan, Korea, China, India and Malaysia. The challenges in the execution of hydrogen as an economical fuel in Asia are also highlighted. © 2013 Elsevier Ltd.


Ebshish A.,National University of Malaysia | Yaakob Z.,National University of Malaysia | Narayanan B.,Sree Neelakanta Government Sanskrit College | Bshish A.,National University of Malaysia | Wan Daud W.R.,National University of Malaysia
Energy Procedia | Year: 2012

Momentous amount of glycerol is produced as a by-product during bio-diesel production by the transesterification of vegetable oils, which are available at low cost in large supply from renewable raw materials. As hydrogen is a clean energy carrier, conversion of glycerol to hydrogen is one among the most attractive ways to make use of glycerol. In this study, the catalytic production of hydrogen by steam reforming of glycerol has been experimentally performed in a fixed-bed reactor. The performance of this process was evaluated over 10wt% Ni supported alumina xerogel catalysts. Ni is impregnated over alumina xerogel which was pretreated at different temperatures of 700°C, 800°C, 900°C and 1000°C. For a comparative purpose, the steam reforming experiments were conducted under same operating conditions, i.e., reaction temperature of 600°C, atmospheric pressure and 1:6 glycerol to water molar ratio where we are getting 100% glycerol conversion in all the runs. The results showed that the hydrogen production increased with the increase in the treatment temperature of the support. The highest amount of hydrogen produced was attained over 10wt% Ni doped alumina xerogel pretreated at 1000°C. The catalytic enhancement over the best catalyst system is due to the thermal stability of the support which is treated at highest temperature. Sol gel method of preparation is implemented in the support development and different catalyst systems used in the reforming process were characterized using X-ray powder diffraction, BET surface area and SEM analysis. © 2012 Published by Elsevier Ltd.


Binitha N.N.,National University of Malaysia | Binitha N.N.,Sree Neelakanta Government Sanskrit College | Suraja P.V.,National University of Malaysia | Yaakob Z.,National University of Malaysia | And 2 more authors.
Journal of Sol-Gel Science and Technology | Year: 2010

In this work we describe and discuss the synthesis, and characterization of Co3O4 nanoflakes prepared by citric acid based sol-gel method using cobalt nitrate precursor. The average crystalline size of Co 3O4 was estimated from the X-ray diffraction peaks of powders using Scherrer's formula. The size of the particles deduced from TEM agrees with XRD based values. The FTIR confirms formation of Co 3O4. The SEM micrographs show the nanoflake morphology. Here we report the lowest temperature sol-gel method of preparation of Co 3O4 nanoflakes and its photocatalytic study for the degradation of dye pollutant methylorange. © Springer Science+Business Media, LLC 2009.


Yaakob Z.,National University of Malaysia | Sukarman I.S.B.,National University of Malaysia | Narayanan B.,Sree Neelakanta Government Sanskrit College | Abdullah S.R.S.,National University of Malaysia | Ismail M.,National University of Malaysia
Bioresource Technology | Year: 2012

Transesterification reaction of Jatropha curcas oil with methanol was carried out in the presence of ash generated from Palm empty fruit bunch (EFB) in a heterogeneous catalyzed process. The ash was doped with KOH by impregnation to achieve a potassium level of 20. wt.%. Under optimum conditions for the EFB-catalyzed (65 °C, oil/methanol ratio of 15, 90. min, 20. wt.% EFB ash catalyst) and the KOH-EFB-catalyzed reactions (65 °C, oil/methanol ratio of 15, 45. min, 15. wt.% of KOH doped EFB ash), biodiesel (>98%) with specifications higher than those stipulated by European biodiesel quality standard EN 14214 was obtained. © 2011 Elsevier Ltd.


Remakanthan A.,Sree Neelakanta Government Sanskrit College | Menon T.G.,Rajiv Gandhi Center for Biotechnology | Soniya E.V.,Rajiv Gandhi Center for Biotechnology
In Vitro Cellular and Developmental Biology - Plant | Year: 2014

An improved, rapid, reproducible, and simple protocol has been developed for somatic embryogenesis in banana cv. 'Grand Naine' using explants derived from actively growing multiple shoot cultures. Many restrictive factors remain in banana embryogenesis such as long duration, unpredictability, and a high degree of genotype dependence. In the present study, we used split shoot tips from 4-wk-old cultures as explants. Somatic embryos were induced in 15 d directly in Murashige and Skoog (MS) medium supplemented with different combinations of 0-8.28 μM picloram and 0.22-4.44 μM 6-benzylaminopurine (BA) without callus formation. Maximum embryo induction (100%) occurred when 4.14 μM picloram and 0.22 μM BA were used. Conversion of somatic embryos into plantlets occurred sporadically (2-3%) in MS medium containing α-naphthalene acetic acid (NAA; 0.53-2.68 μM) together with BA (2.22-44.39 μM), or thidiazuron (4.54 μM) plus glutamine (200 mg/L). This protocol is far superior to those already reported for fast and high frequency induction of somatic embryo. In liquid agitated culture, individual embryos separated easily and produced a large number of secondary embryos within 10 d which, upon transfer to filter paper overlaid on MS liquid medium supplemented with 4.44 μM BA, resulted in conversion (3%) into plantlets. © 2013 The Society for In Vitro Biology.


Deepthi T.V.,Sree Neelakanta Government Sanskrit College | Venugopalan P.,Sree Neelakanta Government Sanskrit College
Inorganica Chimica Acta | Year: 2016

Microwave assisted synthesis of two novel α,β-unsaturated 1,3-diketones, their mononuclear NiII and CuII complexes, characterization, results on DNA binding activities, short term in vitro and in vivo antitumor activities were reported. The ligands are structurally related to curcuminoids and exhibited significant antitumor activity against Dalton's lymphoma ascites cells. The ligands were found to be existing in their enolic form and metal complexes have 1:2 metal ligand stoichiometry evidenced by electronic, IR, 1H NMR, 13C NMR and FAB mass spectral data. The DNA binding properties of ligand and metal complexes were studied by absorption titrations and by viscosity measurements with calf thymus DNA. The intrinsic binding constants of copper(II) complexes are slightly higher than complexes of same metals reported in the literature. Interaction of copper(II) complexes were found to be higher than that of nickel(II) complexes and free ligands. The copper(II) complexes of the ligands were found to be more effective towards Dalton's lymphoma ascites cells in both in vitro and in vivo studies. © 2016 Elsevier B.V.


Pudukudy M.,National University of Malaysia | Pudukudy M.,Sree Neelakanta Government Sanskrit College | Yaakob Z.,National University of Malaysia | Narayanan B.,Sree Neelakanta Government Sanskrit College | And 2 more authors.
Superlattices and Microstructures | Year: 2013

Mesoporous spinel Co3O4 nanomaterials have been prepared effectively via simple solid state mixing of nitrate precursor with various modifiers, including citric acid, urea, glucose and sucrose, followed by thermal treatment. The as-synthesised spinel Co3O4 materials showed high porosity, and the particles were finely crystallised in the nanorange. The different organic modifiers used in the synthetic method played a major role in the development of various porous morphologies. Different analytical techniques were used to study the material's structural and textural features. X-ray diffraction analysis revealed the cubic phase purity of the cobalt oxide nanomaterials. The monoclinic and face centred cubic phases of CoO were detected in the glucose- and sucrose-assisted samples. The scanning electron microscopic images confirmed the surface porosity of the spinels with various morphologies. Macro-porous morphology with large holes was noted in the citric acid-assisted sample. The transmission electron microscopy images indicated that the bimodal mesoporosity of the spinels started from the deep bulk to the surface. BET-BJH analysis indicated that the surface area and pore parameters of the spinels were related to the type of modifier. Moreover, a high surface area was noted for the citric acid-aided Co3O4 (29 m2/g). The bimodal pore-size distributions were clearly confirmed from the TEM and the BJH-porosity measurements. © 2013 Elsevier Ltd. All rights reserved.

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