Evidence of isotropy at large-scale from polarizations of radio sources

We test the isotropy of radio polarization angle orientations with a robust and reliable dual frequency polarimetric survey of active galactic nuclei (AGN). We find that the polarization orientations are consistent with the assumption of isotropy for scales larger than or equal to $\sim 800$ Mpc. This provides further evidence of isotropy at large distance scales and is likely to impose strong constraints on some of the physical mechanisms that may be invoked to explain past observations of alignment of radio and optical polarizations at large distance scales.Comment: 6 pages, 9 figures, accepted for publication in Astronomy & Astrophysics (10/12/2018

Common Fixed Point Theorems for Meir -Keeler Type Contraction Condition

In this article is to prove some more common fixed point theorem in complete metric space by using Meir-Keeler type contractive conditions. Keywords- Fixed point, common fixed point, Meir-Keeler type contractive mapping

Fixed Point and Common Fixed Point Theorem for Expansive Mapping in Fuzzy Metric Space

In this paper, we have endeavored to establish fixed point and common fixed theorem forexpansive mapping in fuzzy metric space.Keywords: Fixed Point, Fixed Point Theorem, Metric Space, Fuzzy Metric Space, ExpansiveMappings.AMS Subject Classification [2000]: 47H10, 54H25, 46J10, 46J1

Doctor of Philosophy

dissertationOil shale is a complex material that is composed of organic matter, mineral matrix and trace amount of bound and/or unbound water. The endothermic decomposition of the organic matter generates liquid and gaseous products. The yield and the desired quality of the product (shale oil) are controlled by the operational conditions. Pyrolysis of a small batch of finely ground oil shale provides chemically controlled intrinsic kinetic rate of organic decomposition. Pyrolysis of large size block/core samples is governed by temperature distributions and the time required for product expulsion. Heat and mass transfer considerations influence the distribution of products and alter the yield and quality. The experimental studies on oil shale pyrolysis performed in this work were designed to understand the relevant coupled phenomena at multiple scales. Oil shale in the Mahogany zone of the Green River formation was used in all experiments. Experiments were conducted at four scales, powdered samples (100 mesh) and core samples of ¾", 1" and 2.5" diameters. Batch, semibatch and continuous flow pyrolysis experiments were designed to study the effect of temperature (300°C to 500°C), heating rate (1°C/min to 10°C/min), pressure (ambient and 500 psi) and size of the sample on product formation. Comprehensive analyses were performed on reactants and products - liquid, gas and spent shale. The activation energies of organic decomposition derived from advanced isoconversional method were in the range of 93 to 245 kJ/mol with an uncertainty of about 10%. Lighter hydrocarbons evolved slightly earlier and their amounts were higher in comparison to heavier hydrocarbons. Higher heating rates generated more alkenes compared to respective alkanes and as the carbon number increased, this ratio decreased. Oil yield decreased and the amount of coke formed increased as the sample size and/or pressure increased. Higher temperature, higher heating rate and low pressure favored more oil yield. The quality of oil improved with an increase in the temperature, pressure and size of the sample. A model in COMSOL multiphysics platform was developed. A general kinetic model was integrated with important physical and chemical phenomena that occur during pyrolysis. The secondary reactions of coking and cracking in the product phase were addressed. The multiscale experimental data generated and the models developed, provide an understanding of the simultaneous effects of chemical kinetics, heat and mass transfers on oil quality and yield. The comprehensive data collected in this study will help advance the move to large scale oil production from the pyrolysis of shale

Weak Lensing Effect on CMB in the Presence of a Dipole Anisotropy

We investigate weak lensing effect on cosmic microwave background (CMB) in the presence of dipole anisotropy. The approach of flat-sky approximation is considered. We determine the functions $\sigma_0^2$ and $\sigma_2^2$ that appear in expressions of the lensed CMB power spectrum in the presence of a dipole anisotropy. We determine the correction to B-mode power spectrum which is found to be appreciable at low multipoles ($l$). However, the temperature and E-mode power spectrum are not altered significantly.Comment: 9 page

Common Fixed Point Theorems for Four Self Maps on A Menger Space, Satisfying Common E. A. Property

In this paper, we prove common fixed point theorems for four self maps by using weak compatibility in Menger spaces. Our result extend, generalized several fixed point theorems on Menger spaces. Keywords— Common fixed points, Metric space, Menger space, weak compatible mappings and E. A. property. AMS subject classification– 47H10, 54H25