Rai H.C.,Bra Bihar University |
Priyanka,Skm University |
Kumar R.,Massachusetts Institute of Technology |
Kumar A.,Bn Mandal University
Asian Journal of Chemistry | Year: 2010
A series of 16-membered macrocyclic complexes of cobalt(II) and nickel(II) of the type [M(H2Cy1-4)] have been synthesized and characterized on the basis of spectral, magnetic and conductivity studies. The macrocyclic ligands H4Cy1-4 are tetrabasic having four imido hydrogen but behave in a dibasic manner. Out of eight nitrogens, four imido and four imino, ligands utilize four imido nitrogens for square planar coordination forming four 7:5:7:5 chelate rings giving rise to a 16 membered macrocyclic framework. The red coloured nickel(II) complexes are diamagnetic in nature, whereas cobalt(II) complexes with chocolate brown colour are of low spin type. Low molar conductivity values in the range 3-7 ohm-1 cm2 mol-1 suggest complexes to be non-electrolytic in nature. High dilute conditions generally employed in the synthesis of macrocyclic complexes in order to dispense with polymerization reaction have been avoided in the present study and advantage of orientation effect has been taken to have high yield.
Srivastava N.,Bn Mandal University |
Singh B.K.,Bn Mandal University |
Yadav A.,Bn Mandal University
National Academy Science Letters | Year: 2014
The paper is based on a population survey conducted for the analysis of epidemiological condition of visceral leishmaniasis from January 2010 to December 2011. The annual incidence (per 10,000) was observed 8.98 for 2010 and 7.71 for 2011. The annual prevalence of disease was 26.92 in 2010 and 23.78 in 2011. The seasonal variation of incidence and its relationship with eco-climatic factors have discussed. The % incidence and temperature represented weak positive correlation with Pearson’s co-efficient value +0.269 (SEr = 0.1892) and linear relationship by regression equation y = 0.116 X + 4.895; whereas % incidence and humidity represented moderate negative correlation with Pearson’s coefficient value −0.649 (SEr = 0.1181) and linear relationship by regression equation y = −0.154 X + 20.40. The retrospective analysis among epidemiological parameters, eco-climatic factors and vector population dynamics are discussed in present paper. It represents internal incubation period of leishmania is 6–8 month in the region under study. © 2014, The National Academy of Sciences, India.