The formation and propagation of electromagnetic waves, specifically the magnetoacoustic waves are studied in this thesis for dense electron-ion magnetoplasmas. The linear and nonlinear waves such as shocks and solitons for small but finite amplitude perturbations are described for various plasma models by taking into account the quantum magnetohydrodynamic model. Further, the possible magnetoacoustic solitary wave interactions, i.e., overtaking and head-on interactions are discussed. The results are numerically analyzed by choosing the plasma parameters consistent with compact astrophysical systems. The properties of nonlinear fast magnetoacoustic waves in dense dissipative magnetoplasmas with degenerate electrons are studied theoretically. For this purpose, the quantum magnetohydrodynamic equations and the reductive perturbation technique are employed to derive the Khokhlov-Zabolotskaya- Kuznetsov (KZK) equation. The assumptions to obtain KZK equation in plasma system and the limiting cases have been identified clearly. Shock solutions of KZK equation are obtained by employing a method based upon Hirota and Clarkson-Kruskal approach. The magnetoacoustic shock waves have been examined numerically to ascertain how the plasma parameters such as ion kinematic viscosity, number density and magnetic field alter the characteristics and dynamics of shock waves. The propagation characteristics of magnetoacoustic shock waves are further investigated in a dense magnetoplasma with spin-1/2 electrons and geometrical effects by deriving the planar Korteweg-de Vries Burgers (KdVB) and cylindrical KdVB equations. Numerically, cylindrical KdVB equation is analyzed and it is observed that the number density, magnetic field and ion kinematic viscosity are the parameters that bring about significant modifications in the structure and propagation of magnetoacoustic shock waves. The spin effects are found to mitigate the phase speed of magnetoacoustic waves and the amplitude of shock structures in a dense magnetoplasma. The amplitude of the shock wave is observed to be greater for the case of cylindrical geometry and is found to propagate faster than that of planar shock waves. Furthermore, the numerical results are compared with the approximate analytical solution to show an excellent agreement of the results in the limit of earlier times. Overtaking interaction of fast magnetoacoustic solitons in dense magnetoplasmas is investigated. In this regard, one dimensional propagation of magnetoacoustic solitary waves in electron-ion plasmas with degenerate electrons is considered by deriving the Korteweg-de Vries (KdV) equation. Numerically, the characteristics of solitary waves are studied by varying the plasma parameters i.e., number density and magnetic field. Hirota bilinear formalism is applied to get the multi-soliton solutions and overtaking interaction of fast magnetoacoustic solitons is explored by utilizing them. It is observed that the values of the propagation vectors determine the interaction of solitary waves. The taller soliton being faster, overtakes the shorter soliton such that the amplitude of the respective solitary waves remain unchanged after the interaction, however they do experience a phase shift. Further, the head-on interaction of two magnetoacoustic solitons is studied in a dense magnetoplasma with spin-1/2 electrons and geometrical effects. The extended Poincaré- Lighthill-Kuo (PLK) technique and quantum magnetohydrodynamic equations are utilized to derive a pair of nonplanar Korteweg-de Vries equations. The PLK method is an analytical approach, which explicitly provides the relations of post collision trajectories and the phase shifts encountered by the magnetoacoustic solitons after interaction. The head-on interaction of two concentric ring solitons is numerically analysed. It is observed that the spin-1/2 effects, statistical pressure, displacement current and geometry of the system significantly modify the phase shifts encountered by the solitons. It is noticed that the increasing the number density decreases the phase shift of the colliding solitons. Furthermore, the cylindrical geometry is observed to decrease the phase shift by comparison with the planar geometry. The investigations carried out in this thesis shall hopefully equip us to comprehend the formation, propagation and interaction of magnetoacoustic solitons in dense magnetoplasmas which exist in compact astrophysical objects like white dwarfs and neutron stars.
Orientalists have always denied the acceptance of the divinity and authenticity of Qur’an. For this purpose, they have presented multifarious objections to prove the Qur’an as a discourse of Muhammad r which he learnt from the Christian monks and derived it from the judeo-Christian sources. They specially mention that Muhammad r was not an illiterate person he was rather a pupil of the monks. In this way, their aim is to prove false the claim of the miraculous (I’jaz) style of the Qur’an. We have proved in this study that according to Quran, Tafaseer and Hadiths of Prophet r, history and logic, that Muhammad r since his birth until his death, was illetrate, did not know how to read or write. In this paper, an effort has been made to examine the Western arguments and deduce the actual position in this matter. The basic and fundamental sources have been used to precede the discussion.
Poultry diseases are a matter of serious concern and responsible for extremely large profit
making crisis in poultry industry per anum. Outbreaks of infectious bursal disease (IBD) are
continuously increasing despite vaccination in commercial broilers. The strains of IBDV
currently circulating in Chakwal district broiler flocks are not known. Clinicopathologic
analysis and reverse transcriptase PCR were used in 18 poultry farms which were situated in
district Chakwal to confirm field outbreaks of IBD. The genetic analysis of the hypervariable
part of the?VP2?gene was utilized to describe different features of total 6 isolates of these
outbreaks. Arrangement of nucleotides, infer amino acid sequences through phylogenetic
analysis of VP2 gene containing hypervariable part were used for dividing IBDV strains into
two groups. According to phylogenetic analysis, 5 IBDV strains showed special signatures of
amino acid in the VP2 gene as A222, I242, I256, I294, S299 and classified as vvIBDV.They
showed 97%?99% identity at the nucleotide level. Furthermore, the sequencing analysis of
detected field strains revealed the high similarity and close clustering with vvIBDV strains
isolated from India, Pakistan, and China, suggesting geographic and temporal relationships
among these strains. Interestingly, one IBDV strain clustered togather with vaccinal IBDV
strains and representing 99% sequence likeness with vaccine strains which were dissipated,
suggesting possible role of attenuated vaccines in the outbreaks of IBD. Our study revealed
circulation of vvIBDV strains in Chakwal broiler flocks and these evidences emphasize the
need of further detailed and more systemic approaches to evaluate IBDV diffusion and
characterization to design effective control strategies.