Sankaralingam P.,Tamilnadu Newsprint and Papers Ltd |
Sankar A.,Kandaswami Kandars College |
Kuppusamy K.,Tamilnadu Newsprint and Papers Ltd |
Subramanian S.,Tamilnadu Newsprint and Papers Ltd
2013 PEERS Conference, Co-located with the 2013 International Bioenergy and Bioproducts Conference | Year: 2013
The bleaching chemistry indicates that pH affects the effectiveness of chlorine dioxide treatment and the standard recommendations has been to maintain a final stage pH range for brightening with chlorine dioxide between 3.5 and 4.0.But we used 16% & 17% TAA cooked Clone Casuarina without Oxygen Delignification (ODL), were bleached in Acidic and Alkaline pH initial chlorine dioxide (DO) stage, followed by Caustic reinforced Hydrogen peroxide (Ep) and final Chlorine dioxide (Dl) stage of bleaching. At constant bleaching condition both Casuarina pulps show these alkaline pH bleaching methods can improve the pulp bleachability without affecting pulp strength properties, optical properties, physical properties and improved effluent characteristics. The Alkaline pH bleached pulp final brightness 86.2 %ISO (16% TAA) and 86.8%ISO (17% TAA) are well compared to Acidic pH final brightness 85.2 %ISO (16% TAA) and 86.2%ISO (17% TAA) initial chlorine dioxide bleaching and followed by extraction reinforced Hydrogen peroxide and final Chlorine dioxide bleaching. Both 16&17% TAA cooked pulps filtrate analysis of the Alkaline pH Do stage, shows lower Colour (14.07 & 16.15 %), Total Dissolved Solids (18.36 & 18.37) and COD (8.47 & 10.33%) than Acidic pH Do bleaching filtrate. Based on results from the Acidic and Alkaline pH bleaching of CJ3 pulp , we found that the optimum pH for initial D0 and final D1 chlorine dioxide bleaching stage should be operated with a final pH close to alkaline, when a typical chlorine dioxide charge is applied and its effluent characteristics shows lesser inorganic load when compared to acidic effluent. Copyright © 2013 by the TAPPI Press. All rights reserved.
Velusamy M.,University of Madras |
Sreenivasan S.,Government Arts College Autonomous |
Kandasamy R.,Kandaswami Kandars College |
Subbu P.,Government Arts College Autonomous |
And 2 more authors.
Chemistry Central Journal | Year: 2015
Background: 1,4-Diazepine derivatives are the seven membered, nitrogen containing heterocyclic ring systems possessing a wide range of therapeutic applications. 1,4-Diazepines attracted the attention of chemists and druggists due to their biological and medicinal properties, such as antimicrobial, anti-HIV and anticancer activities. Herein, we report the preparation, crystal structure determined by X-ray crystallographic methods and docking of the molecules with the potential target protein NS5B RNA polymerase. Results: The crystal structures and conformational studies of 1,4-diazepine [t-3, t-6-dimethyl-r-2,c-7-diphenyl-1,4-diazepan-5-one(DIAZ1)] and its nitroso derivative [t-3, t-6-dimethyl-1-nitroso-r-2,c-7-diphenyl-1,4-diazepan-5-one(DIAZ2)] are reported. The analyses of the molecules reveal that the seven membered diazepine ring systems adopt chair and boat conformations in compounds DIAZ1 & DIAZ2, respectively. In DIAZ2, the oxygen O2A is disordered over two positions with the refined occupancies of 0.792(7): 0.208(7) in the nitroso group. In both DIAZ1 & DIAZ2, the symmetry related molecules form a hetero/homo-dimer through N-H..O hydrogen bonds. Conclusion: In this study, the crystal structures of two new 1,4-diazepines, namely t-3, t-6-dimethyl-r-2,c-7-diphenyl-1,4-diazepan-5-one and t-3, t-6-dimethyl-1-nitroso-r-2,c-7-diphenyl-1,4-diazepan-5-one were synthesized and characterized by X-ray crystallographic methods. The docking studies show that the compounds inhibit at the active site of the target protein and can be utilized as potential drug molecules. In both the compounds, N-H..O hydrogen bonds lead to dimer formation. In DIAZ2, additionally a couple of C-H..O interactions are noted between the molecules. © Velusamy et al.; licensee Springer.
Senthil Kumar D.,Kandaswami Kandars College |
Satheesh Kumar P.,Messina University |
Rajendran N.M.,Pondicherry University |
Uthaya Kumar V.,Tamil University |
Anbuganapathi G.,Kandaswami Kandars College
Journal of Agricultural and Food Chemistry | Year: 2014
Vermicompost was produced from flower waste inoculated with biofertilizers using the earthworm Eisenia fetida. Principal component analysis (PCA) and cluster analysis (CA) were carried out on the basis of physicochemical parameters of vermicomposted samples. From the results of the PCA and CA, it was possible to classify two different groups of vermicompost samples in the following categories: E2 and E5; and E1, E3, E4, and control. Scanning electron microscopy and biodynamic circular paper chromatography analysis were used to investigate the changes in surface morphology and functional groups in the control and vermicompost products. SEM analysis of E1-E5 shows more fragment and pores than the control. Chromatographic analysis of vermicompost indicated the mature condition of the compost materials. © 2014 American Chemical Society.
Ravichandran K.,Kandaswami Kandars College |
Manikannan R.,University of Pardubice |
Muthusubramanian S.,Madurai Kamaraj University |
Ramesh P.,University of Madras |
Ponnuswamy M.N.,University of Madras
Acta Crystallographica Section E: Structure Reports Online | Year: 2013
In the crystal of the title compound, C11H12O 5S2, molecules are linked by O - H⋯O hydrogen bonds and C - H⋯O interactions, forming a three-dimensional network. © Ravichandran et al. 2013.
Sankaralingam P.,Kandaswami Kandars College |
Sankar A.,Kandaswami Kandars College
IPPTA: Quarterly Journal of Indian Pulp and Paper Technical Association | Year: 2013
The bleaching chemistry indicates that pH affects the effectiveness of chlorine dioxide treatment and the standard recommendations have been to maintain a final stage pH range for brightening with chlorine dioxide between 3.5 and 4.0. In Casuarina (CJ9) pulp bleaching sequence, without Oxygen delignification(ODL) stage,we found that the optimum pH for initial Do and final D1 chlorine dioxide bleaching is dependent on chlorine dioxide charge but this stage should be operated with a final pH close to alkaline, when a typical chlorine dioxide charge is applied. We have noticed that maintaining a pH close to alkaline side throughout the bleaching stage. Primary objective of the bleaching sequence is to improve pulp brightness in initial chlorine dioxide treatment, which could later promote more economic and efficient use of bleaching chemicals in the next stage of bleaching. The sulphate scale forming potential of sulphuric acid addition in acidic Do stage and sulphur dioxide addition to reduce residual chlorine could be eliminated and also reaction temperature is reduced by 15°C when compared to ADhotEopD 1 bleaching sequence. The alkaline pH bleaching methods can improve the pulp bleachability without affecting pulp strength properties, optical properties, physical properties and improved effluent characteristics. The target brightness can be effectively achieveded if the first treatment with alkaline pH followed by extracting alkali soluble compounds in a subsequent (Ep) stage, and by then continuing bleaching with final chlorine dioxide (D1) stage. With the increasing cost of wood, the modified continuous cooking (MCC) to lower the pulp kappa number is questioned. A strategic shift in pulping and bleaching is discussed to decrease wood use per ton of pulp while decreasing the kappa number of pulp to bleach plant. Such a shift would allow the mills to lower bleaching cost, comply with the environmental requirements and, allow the closure of bleach plants effectively.