Time filter

Source Type

Shanmugaraju A.,Arul Anandhar College | Syed Ibrahim M.,Arul Anandhar College | Moon Y.-J.,Kyung Hee University | Mujiber Rahman A.,Hajee Karutha Rowther Howdia College | Umapathy S.,Madurai Kamaraj University
Solar Physics | Year: 2015

We analyzed the physical characteristics of 40 halo coronal mass ejections (CMEs) and their geo-effective parameters observed during the period 2011 to 2013 in the rising phase of Solar Cycle 24. Out of all halo CMEs observed by SOHO/LASCO, we selected 40 halo CMEs and investigated their geomagnetic effects. In particular, we estimated the CME direction parameter (DP) from coronagraph observations, and we obtained the geomagnetic storm disturbance index (Dst) value corresponding to each event by following certain criteria. We studied the correlation between near-Sun parameters of CMEs such as speed and DP with Dst. For this new set of events in the current solar cycle, the relations are found to be consistent with those of previous studies. When the direction parameter increases, the Dst value also increases for symmetrical halo CME ejections. If DP>0.6, these events produce high Dst values. In addition, the intensity of geomagnetic storm calculated using an empirical model with the near-Sun parameters is nearly equal to the observed values. More importantly, we find that the geo-effectiveness in the rising phase of Solar Cycle 24 is much weaker than that in Cycle 23. © 2015, Springer Science+Business Media Dordrecht.


Parveen M.F.,Hajee Karutha Rowther Howdia College | Umapathy S.,Madurai Kamaraj University | Dhanalakshmi V.,KCET | Anbarasan R.,KCET | Anbarasan R.,National Taiwan University
Composite Interfaces | Year: 2010

Nano-sized Zn(OH)2 was synthesized by the co-precipitation method. Further, the structure and properties were tested with FTIR, UV-visible spectroscopy, XRD and TGA as analytical tools. The structural morphology and size of the Zn(OH)2 synthesized by the co-precipitation method were determined by using FESEM and HRTEM techniques. The effect of the synthesized nano-sized Zn(OH)2 on the structural and thermal properties of PVA matrix was tested and discussed. © Koninklijke Brill NV, Leiden, 2010.


Parveen M.F.,Hajee Karutha Rowther Howdia College | Umapathy S.,Madurai Kamaraj University | Dhanalakshmi V.,KCET | Anbarasan R.,National Taiwan University
Journal of Applied Polymer Science | Year: 2010

Nanosized Fe(OH)2 was synthesized by a coprecipitation method. Peaks between 500 and 1250 cm-1 in Fourier transform infrared (FTIR) spectroscopy confirmed the presence of metal hydroxide stretching. X-ray diffraction showed the suppressed crystalline system of Fe(OH) 2/aniline (ANI) due to the presence of a higher weight percentage of the dispersing agent, ANI. Thermogravimetric analysis implied that 75.5 wt % of residue remained up to 800°C. High resolution transmission electron microscope (HRTEM) analysis of Fe(OH)2/ANI revealed that its size ranged from 10 to 50 nm with a rodlike morphology. Scanning electron microscopy implied that pristine Fe(OH)2 had a nanotriangular platelet morphology, and a higher weight percentage of dispersing agent intercalated with Fe(OH)2 had a spheroid with an agglomerated structure. The (UV-visible) spectrum implied the presence of Fe2+ ions at 326 nm and the existence of an amino group intercalated with Fe(OH)2 showed a sharp peak at 195 nm, the intensity of which increased with increasing intercalated dispersing agent weight percentage. Photoluminescence showed that ANI-intercalated Fe(OH)2 showed a lesser intensity than the pristine Fe(OH)2. © 2010 Wiley Periodicals, Inc.


Sundaram M.M.,Center for Research and Post Graduate Studies in Chemistry | Sivakumar S.,Center for Research and Post Graduate Studies in Chemistry | Sivakumar S.,Hajee Karutha Rowther Howdia College
Indian Journal of Environmental Protection | Year: 2013

The present study investigate the successful use of eco-friendly adsorbents areca nut shell carbon (ASC) and cashew nut shell carbon (CSC) to remove congo red (CR) dye. In the batch experiments, various parameters, such as effect of initial concentration, contact time, dose, pH and particle size has been studied. The amount of dye removal increased with decrease in the initial concentration, decrease in particle size, decrease in pH, increase in contact time and dosage. The experimental results were analysed by using Freundlich and Langmuir isotherm models and first order kinetic equations. .The intra particle diffusion study shown that the process favour first order kinetics. Surface morphology of the adsorbents ASC and CSC before and after adsorption is studied by scanning electron microscopy (SEM). The result indicate that the low cost adsorbents cashewnut shell carbon (CSC) and Areca nut shell carbon (ASC) can be used as an effective adsorbents alternative to commercial activated carbon (CAC) in wastewater treatment for the removal of congo red (CR). © 2013 - Kalpana Corporation.


Mujiber Rahman A.,Hajee Karutha Rowther Howdia College | Shanmugaraju A.,Arul Aanandar College | Umapathy S.,Hajee Karutha Rowther Howdia College | Umapathy S.,Radio Astronomy Center
Advances in Space Research | Year: 2013

We have analyzed 101 Coronal Mass Ejection (CME) events and their associated interplanetary CMEs (ICMEs) and interplanetary (IP) shocks observed during the period 1997-2005 from the list given by Mujiber Rahman et al. (2012). The aim of the present work is to correlate the interplanetary parameters such as, the speeds of IP shocks and ICMEs, CME transit time and their relation with CME parameters near the Sun. Mainly, a group of 10 faster CME events (V INT > 2200 km/s) are compared with a list of 91 normal events of Manoharan et al. (2004). From the distribution diagrams of CME, ICME and IP shock speeds, we note that a large number of events tends to narrow towards the ambient (i.e.; background) solar wind speed (∼500 km/s) in agreement with the literature. Also, we found that the IP shock speed and the average ICME speed measured at 1 AU are well correlated. In addition, the IP shock speed is found to be slightly higher than the ICME speed. While the normal events show CME travel time in the range of ∼40-80 h with a mean value of 65 h, the faster events have lower transit time with a mean value of 40 h. The effect of solar wind drag is studied using the correlation of CME acceleration with interplanetary (IP) acceleration and with other parameters of ICMEs. While the mean acceleration values of normal and faster CMEs in the LASCO FOV are 1 m/s2, 18 m/s2, they are -1.5 m/s2 and -14 m/s2 in the interplanetary medium, respectively. The relation between CME speed and IP acceleration for normal and faster events are found to agree with that of Lindsay et al. (1999) and Gopalswamy et al. (2001) except slight deviations for the faster events. It is also seen that the faster events with less travel time face higher negative acceleration (>-10 m/s2) in the interplanetary medium up to 1 AU. © 2013 COSPAR. The Authors. Published by Elsevier Ltd. All rights reserved.


Shahul Hameed K.,Hajee Karutha Rowther Howdia College | Muthirulan P.,Center for Research and Post Graduate Studies in Chemistry | Meenakshi Sundaram M.,Center for Research and Post Graduate Studies in Chemistry
Arabian Journal of Chemistry | Year: 2013

The use of low-cost, easily obtained and eco-friendly adsorbents has been employed as an ideal alternative to the current expensive methods of removing dyes from wastewater. This study investigates the potential use of activated carbons such as aamla seed carbon (ASC), jambul seed carbon (JSC), tamarind seed carbon (TSC) and soapnut carbon (SNC) for the removal of chromotrope (CH) dye from simulated wastewater. The obtained results were compared with that of Commercial Activated Carbon (CAC). The effects of different system variables, adsorbent dosage, pH and particle size were studied. The results showed that as the amount of the adsorbent increased, the amount adsorbed per unit mass decreased accordingly. Optimum pH value for dye adsorption was determined as ∼2.0. The adsorption of chromotrope fit well into pseudo-second-order rate equation. The adsorption also obeyed Langmuir and Redlich-Peterson equations better than Temkin, Freundlich and Dubinin-Radushkevich (D-R) equations. The adsorption capacities of low cost adsorbents were found to be in the following order ASC > JSC > TSC > SNC. The activated carbons prepared were characterized by FT-IR and SEM analysis. © 2013.


Parthiban K.,Hajee Karutha Rowther Howdia College | Sheik Mydeen C.,Hajee Karutha Rowther Howdia College | Abdul Raheem M.,Hajee Karutha Rowther Howdia College
Asian Journal of Epidemiology | Year: 2014

Immunization status of children in Chinnamanur and Cumbum area were studied. It was noticed that extended package of vaccination and oral polio vaccination coverage reaches 100%. But the immunization rate declined dramatically with increase in age of children. The study clearly shows there is a positive correlation between the parent's education and immunization coverage. But in some cases educated parents fails to vaccinate their children after eight years. Promotion and creating awareness to the parents about complete vaccination may reach cent percent in future to create disease free society. © 2014 Asian Network for Scientific Information.


Sangiliapillai R.,Hajee Karutha Rowther Howdia College | Arumugam R.,Madurai Kamaraj University | Eswaran R.,Madras Christian College | Seenivasan R.,Madurai Kamaraj University
Journal of Fluorescence | Year: 2015

Four [Ru(NN)3]2+ complexes (NN∈=∈polypyridine) with ligands of varying hydrophobicity with different charges +2, 0 and -4 were synthesized. The photophysics and photoinduced electron transfer reactions of these Ru(II)-complexes with dimethylaniline (DMA) as the quencher have been studied in aqueous medium and ionic and non-ionic micellar medium. The extent of binding of the complexes with the surfactant interface is evident from the calculated binding constant values (K). Dimethylaniline (DMA) being a neutral quencher, the hydrophobic and electrostatic interactions competing with one another and their combined effect with the surfactants were reported by observing the quenching rate constant (kq) values. The formation of anilinium cation radical in transient absorption spectrum confirms the excited state electron transfer reactions of ruthenium(II) complexes with dimethylaniline. The calculated rate constant values (kq) are in good agreement with the experimental kq values giving quantitative evidence for the bimolecular reductive quenching rate constant for the complexes with DMA. Pseudophase ion exchange model is successfully applied to analyse the quenching data. © 2014 Springer Science+Business Media New York.


Sangiliapillai R.,Hajee Karutha Rowther Howdia College | Arumugam R.,Madurai Kamaraj University | Eswaran R.,Madras Christian College | Seenivasan R.,Madurai Kamaraj University
Luminescence | Year: 2016

Luminescent heteroleptic ruthenium(II) complexes of type RuLnX3-n [L = 1,10-phenanthroline (phen), X = 4,7 diphenyl phenanthroline disulfonate, (dpsphen) n = 0,1,2,3] were synthesized and their photophysical properties investigated in homogeneous and cationic (CTAB), anionic (SDS) and nonionic (Triton X-100) micelles. The luminescent quantum yield and lifetime of the complexes were found to increase in the presence of micellar media and on the introduction of a disulfonate ligand into the coordination sphere. Both electrostatic and hydrophobic interactions play an important role in the micellar media. Thus, by changing the nature of the ligands and the medium, we were able to tune the photophysical properties of Ru(II) complexes. © 2015 John Wiley & Sons, Ltd.


PubMed | Madurai Kamaraj University, Hajee Karutha Rowther Howdia College and Madras Christian College
Type: Journal Article | Journal: Luminescence : the journal of biological and chemical luminescence | Year: 2016

Luminescent heteroleptic ruthenium(II) complexes of type RuLn X(3-n) [L=1,10-phenanthroline (phen), X=4,7 diphenyl phenanthroline disulfonate, (dpsphen) n=0,1,2,3] were synthesized and their photophysical properties investigated in homogeneous and cationic (CTAB), anionic (SDS) and nonionic (Triton X-100) micelles. The luminescent quantum yield and lifetime of the complexes were found to increase in the presence of micellar media and on the introduction of a disulfonate ligand into the coordination sphere. Both electrostatic and hydrophobic interactions play an important role in the micellar media. Thus, by changing the nature of the ligands and the medium, we were able to tune the photophysical properties of Ru(II) complexes.

Loading Hajee Karutha Rowther Howdia College collaborators
Loading Hajee Karutha Rowther Howdia College collaborators