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Kanyakumari District, India

Bansal C.,University of Hyderabad | Brightson M.,St Judes College
Phase Transitions | Year: 2015

(Ag2)xCu1− xS, x = .2, .4, .6 and .8 nanoparticles were synthesized by the solvothermal method. The as-synthesized nanoparticles were characterized by X-ray diffraction to study the crystal structure and size. The surface morphologies of the above samples were studied using scanning electron microscope. As there is continuous shift in the lower wavelength absorption edge of the UV–VIS spectrum of these samples with concentration, (Ag2)xCu1− xS nanoparticles can be tuned to different band gap energies by varying the composition. The D.C. electrical resistance was measured in the temperature range 310–485 K. As Ag2S transforms from monoclinic to bcc at around 450 K, copper sulfide nanoparticles also shows a phase transition at around 470 K, the effects of these two transitions are seen in the resistance measurements and in the UV–VIS spectra of the entire system. The electrical resistance of (Ag2)xCu1− xS nanoparticles rapidly reduces as more and more copper sulfide is added. © 2015 Taylor & Francis

Vilfred K.,St Judes College | Suryakala A.,Sree Devi KumariWomens College
Tamkang Journal of Mathematics | Year: 2015

For a,d,n ∈ ℕ, we define (a,d)-Continuous Monotonic Subgraph Decomposition or (a,d)-CMSD of a graph G of size (Formula presented.) as the decomposition of G into n subgraphs G1, G2,..., Gn without isolated vertices such that each Gi is connected and isomorphic to a proper subgraph of Gi+1 and |E(Gi)| = a+(i-1)d for i = 1, 2,..., n. (1,1)-CMSD of a graph G is called a Continuous Monotonic Subgraph Decomposition or CMSD of G. Harary introduced the concepts of sum and integral sum graphs and a family of integral sum graphs G-n,n over [-n,n] and it was generalized to G-m,n where [r,s] = {r,r+1,..., s}, r,s ∈ ℤ and m,n ∈ ℕ0. In this paper, we study (a,d)-CMSD of Kn+1 and G0,n into families of triangular books, triangular books with book mark and Fans with handle.

Nicholas T.,St Judes College
Tamkang Journal of Mathematics | Year: 2010

A graph is said to be a sum graph if there exists a set S of positive integers as its vertex set with two vertices adjacent whenever their sum is in S. An integral sum graph is defined just as the sum graph, the difference being that the label set S is a subset of Z instead of set of positive integers. The sum number of a given graph G is defined as the smallest number of isolated vertices which when added to G results in a sum graph. The integral sum number of G is analogous. In this paper, we mainly prove that any connected graph G of order n with at least three vertices of degree (n - 1) is not an integral sum graph. We characterise the integral sum graph G of order n having exactly two vertices of degree (n - 1) each and hence give an alternative proof for the existence theorem of sum graphs.

Hentry C.,St Judes College | Chandrasekar N.,Manonmaniam Sundaranar University | Saravanan S.,Manonmaniam Sundaranar University | Sahayam J.D.,Manonmaniam Sundaranar University
Bulletin of Engineering Geology and the Environment | Year: 2010

The paper reports a study of the effects of the 26th December 2004 tsunami on a 3 km length of coastline in southern India. GIS maps were prepared based on field surveys and accounts given by eye-witnesses and survivors. It is concluded that the main height and run-out of the wave were much affected by the on-shore topography and off-shore bathymetry. Where the water immediately off-shore is deepest, the wave was highest, reaching some 10 m. The extent of the inundation is exacerbated by the presence of creeks/estuaries, where it extended to a kilometer inland, and minimized by the presence of a rocky coastline. Recommendations are made to mitigate the hazard. © 2010 Springer-Verlag.

Vethanathan S.J.K.,St Johns College | Brightson M.,St Judes College | Sundar S.M.,Sri Paramakalyani College | Perumal S.,S T Hindu College
Materials Chemistry and Physics | Year: 2011

Undoped and Manganese doped Zinc Oxide were prepared by solvothermal technique. The structural analysis was carried out using X-ray diffraction. It showed that the undoped Zinc Oxide and Manganese doped Zinc Oxide nanocrystals to exhibit hexagonal wurtzite structure. Grain sizes were estimated from Atomic Force Microscopy and Transmission Electron Microscopy images. The surface morphological studies from Scanning Electron Microscope, Transmission Electron Microscope and Atomic Force Microscope depicted spherical particles with formation of clusters. The magnetic behavior studied by Vibrating Sample Magnetometer indicated paramagnetic behaviour. Hyperfine splitting is observed using Electron Spin Resonance studies. © 2010 Elsevier B.V. All rights reserved.

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