<p>Shiv Nadar University is a comprehensive, multidisciplinary, research-focused, and student-centric University offering a full range of academic programs at the undergraduate, postgraduate and doctoral level. With state-of-the-art infrastructure, the University comprises of academic wings, sophisticated labs, international standard sports facilities, amphitheaters, auditorium, conference rooms and smart classrooms. The University&rsquo;s goal is to become internationally recognized for the quality of its research and creative endeavors and their applicability to improving quality of life, generating new insights and expanding the boundaries of human knowledge creativity. Committed to excellence in teaching, research and service, the University aims to serve the higher education needs of India and the world beyond.</p>

Shiv Nadar University

(SoNS) School of Natural Sciences

In this paper, we report the results derived from a statistical analysis of whistlers recorded at Varanasi during the period January 1990-December 1999. The monthly occurrence rate shows a maximum during January to March. In order to study the role of geomagnetic disturbance on the whistler occurrence rate, we have used the KP index and its variation. It is found that the occurrence probability monotonically increases with ∑KP (daily sum) values. It is found that, when ∑KP&gt;20, the occurrence rate is greater than the average value, in good agreement with results reported by other workers. In addition, we also present the probability of the observation of whistlers during weak/intense geomagnetic storms and also during the main phase and recovery phase of geomagnetic storms. © 2007 Elsevier Ltd. All rights reserved.

World University root node

Life Sciences

Planetary and Space Science

Role of geomagnetic disturbance on whistler occurrence at a low latitude station

Physics

2007 International Semiconductor Device Research Symposium, ISDRS

Evolution of annealed undoped single crystal ZnO surfaces and implications for Schottky barrier height

Physical Review Letters

Condensed Matter: Electronic Properties, etc.-Importance of Van Der Waals Interaction for Organic Molecule-Metal Junctions: Adsorption of Thiophene on Cu (110) as a Prototype

We report on the structural, electrical, and optical properties of 5% niobium doped TiO2 thin films grown on various substrates by pulsed laser deposition. The epitaxial anatase Nb: TiO2 film on LaAlO3 is shown to be an intrinsic transparent metal and its metallic property arises from Nb substitution into Ti site as evidenced by the Rutherford backscattering channeling result. In contrast, the rutile Nb: TiO2 thin films show insulating behaviors with 2-3 orders higher room temperature electrical resistivity and ∼30 times lower mobility. A blueshift in the optical absorption edge is observed in both phases, though of differing magnitude. © 2007 American Institute of Physics.

Fulltext

Journal of Applied Physics

Niobium doped TiO2: Intrinsic transparent metallic anatase versus highly resistive rutile phase

We describe the use of dipole lattice sums to estimate the electric field experienced by a molecule in a crystal, and apply it iteratively to ab initio calculations on a number of molecules of interest for nonlinear optical applications. The results demonstrate that it represents an efficient and reliable route to estimating molecular dipole moments in crystals. Typical dipole moment enhancements are in the range of 10-40%, agreeing well with the range resulting from partitioning of crystal Hartree-Fock electron densities, but much less than has been suggested in some previous work, and in particular from charge density analysis of X-ray diffraction data. © 2007 Elsevier B.V. All rights reserved.

Chemistry

Chemical Physics Letters

The use of dipole lattice sums to estimate electric fields and dipole moment enhancement in molecular crystals

The structure and magnetism of ZnO-based solid solutions, dilute magnetic semiconductors, with nickel solute were obtained via a solvothermal method. Compared with previous methods for solid solution DMSs, our synthesis method was really facile and economical. The one-dimensional solid solution of Zn 1-xNixO nanostructures were grown in a alcoholic solution. Moreover, the percentage of doped nickel can be easily controlled. The X-ray diffraction, transmission electron micrograph and magnetization hysteresis loops of nickel-doped ZnO nanocrystals were presented to confirm that the nickel impurities are embedded inside the nanocrystal. {\textcopyright} 2007 Materials Research Society.

Materials Research Society Symposium Proceedings

Synthesis and characterization of nickel-doped ZnO nanocrystals

In this paper, we propose a mathematical model of viral infection in pest control. As the viral infection induces host lysis which releases more virus into the environment, on the average 'κ' viruses per host, κ (1,∞), so the 'virus replication parameter' is chosen as the main parameter on which the dynamics of the infection depends. There exists a threshold value κ0 beyond which the infection persists in the system. Still for increasing the value of κ, the endemic equilibrium bifurcates towards a periodic solution, which essentially indicates that the viral pesticide has a density-dependent 'numerical response' component to its action. Investigation also includes the dependence of the process on predation of natural enemy into the system. A concluding discussion with numerical simulation of the model is also presented. © 2007 Society for Mathematical Biology.

Mathematics

Bulletin of Mathematical Biology

The role of viral infection in pest control: A mathematical study

Genetic diversity among 47 ber accessions belonging to cultivated species (Ziziphus mauritiana Lam) and one wild accession of Ziziphus nummularia (Burm F) Willed was investigated using Inter-Simple Sequence Repeat (ISSR) markers. A total of 167 amplification products were detected with 18 ISSR primers of which 152 (89.96%) were polymorphic. Most of the primers that produced distinct bands (14 primers out of 18) contained dinucleotide repeats. Primers based on (AC)n and (AG)n repeats produced more polymorphic bands. Genetic similarity ranging from 43.07% to 90.30% suggested that the 48 Ziziphus genotypes used in the study were divergent. Cluster analysis based on UPGMA method and Bootstrap analysis separated all the 48 genotypes in four distinct clusters. The present study has successfully distinguished morphologically similar genotypes that emphasize the use of molecular markers to the taxonomists. Morphologically similar but genetically distinct genotypes, identified using ISSR markers could be potential sources for genotype identification and to resolve controversies over misnomination of her genotypes. Present study is the first report on the exploitation of ISSR markers in her for genetic diversity analysis.

Journal of Plant Biochemistry and Biotechnology

Assessment of genetic diversity in Ziziphus mauritiana using inter-simple sequence repeat markers

This paper emphasizes on mathematical and field work approach to diagnosing the environmental pollution for Indore, India. These applications are based on the time-series statistics and for three semi-industrial as well as residential areas. The generalized additive models finds as a best fit-model in terms of autocorrelation and reduction of over-dispersion. The interdisciplinary study works on the principal of pollutant source, meteorological parameters, pollutant types, emission rates and various chemical processes. Several chemical or industrial processes like iron and steel production, combustion of fossil fuels, biomass burning, thermal power plants are major polluter in most of the mega cities. © 2007 Springer Science+Business Media, LLC.

Bulletin of Environmental Contamination and Toxicology

A comparative emission profile of an urban area in Madhya Pradesh, India

An intramolecular Schmidt reaction strategy for the synthesis of various derivatives of crispine A using azido-ketone as a key intermediate is described.