ADM College for women

Nāgappattinam, India

ADM College for women

Nāgappattinam, India
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Madhurambal G.,ADM College for Women | Mariappan M.,H H The Rajahs College | Hariharan S.,Government of Tamilnadu | Ramasamy P.,SSN College of Engineering | Mojumdar S.C.,Trencin University Of bcek
Journal of Thermal Analysis and Calorimetry | Year: 2013

Mixed crystals of various proportions of zinc magnesium ammonium sulfate were grown by slow evaporation of aqueous solution at room temperature. The bright and transparent crystals obtained were characterized through thermal (TG-DTA) and FTIR spectral analyses. A fitting decomposition pattern for the compound was formulated on the TG curve which shows two stage mass losses between 133 and 478.75 C. DTA curve shows exothermic peaks in this temperature range supporting the formulated decomposition pattern. The FTIR spectra show the vibration frequencies due to the formation of zinc magnesium ammonium sulfate mixed crystals. Detailed structural analysis of the compound is under progress. © 2013 Akadémiai Kiadó, Budapest, Hungary.


Ramamurthi K.,Bharathidasan University | Madhurambal G.,ADM College for Women | Ravindran B.,EGS Pillay Engineering College | Mariappan M.,EGS Pillay Engineering College | And 2 more authors.
Journal of Thermal Analysis and Calorimetry | Year: 2011

The growth and characterization of a new non-linear organometallic crystal, potassium thiourea thiocyanide (PTT) is reported. The growth of single crystals was accomplished by the slow evaporation solution growth method. The grown crystals were characterized by XRD, TG-DTA, UV, and FTIR spectral analyses. PTT has good optical transmission in the entire visible region which is an essential requirement for a non-linear crystal. TG curve of PTT undergoes complete decomposition between 176 and 1,000 °C in three steps with corresponding three DTA peaks. The high thermal stability of organometallic crystals are due to strong bonding existing between the conjugation layers of thiourea molecule and the potassium ions. © 2011 Akadémiai Kiadó, Budapest, Hungary.


Madhurambal G.,ADM College for Women | Ravindran B.,Anjalai Ammal Mahalingam Engineering College | Mariappan M.,RVS College of Engineering and Technology | Mojumdar S.C.,University of New Brunswick
Journal of Thermal Analysis and Calorimetry | Year: 2010

A single crystal of sodium and potassium cinnamates was grown by slow evaporation of methanol solution at room temperature. The effect of metals sodium and potassium on the electronic structure of cinnamic acid was studied. In this research many analytical methods such as FTIR, UV, second harmonic generation (SHG) and TG-DTA were used: The spectroscopic studies lead to conclusions containing the distribution of the electronic charge in molecule, the delocalisation of π electrons and the reactivity of metal complexes. The SHG efficiency is more pronounced in the presence of sodium and potassium dopant in the growth medium. Incorporation of sodium and potassium increase the thermal stability ensuring the suitability of material for possible non-linear optical (NLO) application up to 180 °C. © Akadémiai Kiadó, Budapest, Hungary 2010.


Ramasamy G.,Annamalai University | Bhagavannarayana G.,National Physical Laboratory India | Madhurambal G.,Adm College For Women | Meenakshisundaram S.,Annamalai University
Journal of Crystal Growth | Year: 2012

Mixed crystals Zn xMg (1-x)(NH 4) 2(SO 4) 2·6H 2O of the two well-known Tuttons salts Zn(NH 4) 2(SO 4) 2·6H 2O and Mg(NH 4) 2(SO 4) 2·6H 2O were grown with varying molar proportions (x=0.10-0.90) by slow evaporation solution growth technique. The mixed crystal Zn 0.54Mg 0.46(NH 4) 2(SO 4) 2·6H 2O is crystallizing in monoclinic system with space group P2 1/c and cell parameters a=6.2217(4) Å, b=12.5343(7) Å, c=9.2557(6) Å, β=106.912(3)°. The coexistence of zinc and magnesium ions in the mixed crystal was confirmed by inductively coupled plasma (ICP), atomic absorption spectroscopy (AAS) and energy dispersive X-ray spectroscopy (EDS). Compositional dependence of lattice parameters follows Vegards relations. Slight variations are observed in FT-IR and XRD of pure and mixed crystals. Comparison of crystalline perfection as evaluated by high-resolution X-ray diffraction (HRXRD) for mixed crystals of various proportions reveals a reasonably good crystalline perfection for the mixed crystal with nearly equimolar ratio of Zn and Mg. The surface morphology of the mixed crystals changing with composition was studied by scanning electron microscopy (SEM). UV-vis studies reveal that the transparency of the mixed crystals was not much affected. © 2012 Elsevier B.V.


Meenakshisundaram S.P.,Annamalai University | Parthiban S.,Annamalai University | Kalavathy R.,Annamalai University | Madhurambal G.,ADM College for Women | And 3 more authors.
Journal of Thermal Analysis and Calorimetry | Year: 2010

The influence of heteroaromatic N-base (1,10-phenanthroline) (Phen), a new additive as complexing agent on tris(thiourea)zinc(II)sulphate (ZTS) crystals from aqueous solutions at 30 °C is investigated. Crystals were grown using low concentration of the dopant (0.005 M L-1) in the aqueous growth medium and the growth promoting effect (GPE) is much greater because of an increase in the metastable zone width. High dopant concentration decreases GPE. The crystalline perfection of the grown crystals is quite good both in doped and undoped crystals as evaluated by high-resolution X-ray diffractometry (HRXRD). The diffraction curve of a typical Phen doped as-grown ZTS crystal was observed to contain a single peak indicating that the crystal does not contain any epitaxial layer on the surface or internal structural grain boundaries. Not much variation is observed in FT-IR and XRD of pure and doped ZTS. Phen depresses the NLO efficiency of ZTS. It could be ascribed due to the disturbance of charge transfer in the presence of the dopant. The grown crystals were also characterized by UV-Vis, SEM and TG-DTA techniques. © Akadémiai Kiadó, Budapest, Hungary 2010.


Parthiban S.,Annamalai University | Murali S.,Annamalai University | Madhurambal G.,ADM College for Women | Meenakshisundaram S.P.,Annamalai University | Mojumdar S.C.,University of New Brunswick
Journal of Thermal Analysis and Calorimetry | Year: 2010

The influence of doping the transition metal Zn(II) on potassium hydrogen phthalate (KHP) crystals has been studied. A close observation of FT-IR and XRD profiles of doped and undoped samples reveals some minor structural variations. It appears that the crystal undergoes considerable lattice stress as a result of doping the bivalent zinc. Furthermore, the possibility of cation vacancies aroused owing to the substitution of K1+ by Zn2+ could result in a defective crystal system. Energy dispersive spectra reveal the incorporation of Zn(II) in the crystalline matrix of KHP crystals. Differential scanning calorimetry (DSC) and TG-DTA studies reveal the purity of the sample and no decomposition is observed below the melting point. Small quantity additions of Zn(II) enhance the fluorescence intensity of KHP crystals. The doping results in morphological changes and significantly improves the second harmonic generation (SHG) efficiency of the host crystal. © Akadémiai Kiadó, Budapest, Hungary 2010.


Madhurambal G.,ADM College for Women | Mariappan M.,EGS Pillay Engineering College | Mojumdar S.C.,University of New Brunswick
Journal of Thermal Analysis and Calorimetry | Year: 2010

A single crystal of urea-thiourea was grown by slow evaporation of aqueous solution at room temperature. The bright and transparent crystals obtained were characterised by TG-DTA, UV and FTIR spectral analyses. A fitting decomposition pattern for the title compound was formulated on the TG curve which shows a two stage mass loss between 200 and 750 °C. DTA curve shows exothermic peaks supporting the formulated decomposition pattern in this temperature range. The UV and FTIR spectra show the characteristic absorption, vibration frequencies due to urea-thiourea zinc chloride crystals. Detailed structural analysis of the compound is under progress. © Akadémiai Kiadó, Budapest, Hungary 2010.


Mariappan M.,EGS Pillay Engineering College | Madhurambal G.,ADM College for Women | Ravindran B.,EGS Pillay Engineering College | Mojumdar S.C.,University of New Brunswick | And 2 more authors.
Journal of Thermal Analysis and Calorimetry | Year: 2011

Single crystals of a new nonlinear optical material, bisthiourea-urea have been grown from aqueous solution by slow evaporation technique with a period of 4 weeks. The structure of the grown crystals was confirmed by X-ray diffraction (XRD). The presence of title compound in the crystal lattice has been qualitatively determined by FTIR analysis. The mechanical properties and thermal stability of the grown crystals were evaluated by Vickers microhardness test and TG and DTG, respectively. © 2011 Akadémiai Kiadó, Budapest, Hungary.


Ravindran B.,EGS Pillay Engineering College | Madhurambal G.,ADM College for Women | Mariappan M.,EGS Pillay Engineering College | Mojumdar S.C.,University of New Brunswick | And 2 more authors.
Journal of Thermal Analysis and Calorimetry | Year: 2011

Thiourea Urea Zinc (II) Chloride (TUZC), a new semiorganic non-linear optical material has been synthesized. The solubility studies have been carried out at room temperature. Single crystals of different proportions of TUZC have been grown by slow evaporation of saturated aqueous solution at room temperature. The FTIR and UV spectral bands have been compared with urea, thiourea and bis Thiourea Zinc Chloride (BTZC). The TG curve showed a two steps mass loss on heating the compound between 30 and 800 °C corresponding to two exothermic DTA peaks at 181-183 and 250-252 °C. © 2011 Akadémiai Kiadó, Budapest, Hungary.


Madhurambal G.,ADM College for Women | Prabha N.,ADM College for Women | Lakshmi S.P.,ADM College for Women | Mojumdar S.C.,ADM College for Women | And 2 more authors.
Journal of Thermal Analysis and Calorimetry | Year: 2013

Various crystals are seen in human urine. Oxalate, Phosphate, Uric acid, and Urate crystals are generally seen in urinary calculi. Calcium stones are most common, comprising 75 % of all urinary calculi. They may be pure calcium oxalate or calcium phosphate or a mixture of both. Many stones are not homogeneous. Low calcium intake increases the intestinal absorption of calcium, thus decreasing the amount of calcium available in the intestinal tract to form insoluble complexes with Oxalate. Consequently, a higher amount of oxalate is available for intestinal absorption and as a result, urinary oxalate excretion increases. Mineral water consumption did not reduce urinary oxalate excretion. High urinary excretion and concentration of magnesium decrease both the nucleation and growth rates of calcium oxalate crystals in urine, because of the higher solubility of magnesium oxalate compared with calcium oxalate. Analytical results show calcium oxalate to be one of the major inorganic components of renal stones and found to be present in almost all kidney and bladder stones. About 39.5 % of the total composition of the calculi is found to contain purely calcium oxalate and also hydroxyl apatite. The ten samples are a mixture of calcium oxalate and phosphate stones. Four samples are calcium oxalate as major composition and the remaining are calcium phosphate as major composition. These kidney stones are taken photographically and size of the stone are measured using optical microscopy. These qualitative analyses are also confirmed by UV, FTIR, DSC, and XRD analysis. © 2013 Akadémiai Kiadó, Budapest, Hungary.

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