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In the present work, we try to find a solution without singularity of Einstein's field equations for the spherically symmetric perfect fluid objects, accurately strange quark spheres, taking into consideration Schwarzschild metric as the outside space-time. An ensemble of inside solutions found on the basis of the simplest linear state equation in the specific form p r = αρ − β. The energy density ρ(r), the radial pressure p r (r) and the tangential pressure p t (r) are devoid of any singularity and exhibit a wellbehaved nature within the generalized anisotropic solution for compact spherical object. The generalized TOV equation is very much preserved inside the system and all energy conditions are excellent. The stability of the matter distribution of our system is checked by the concept of Herrera's cracking and the condition of causality is all around fulfilled for our models. The adiabatic index of our specific configuration is greater than 4/3 in all interior points of the system and the mass-to-radius ratio in our situation is determined also lies within the Buchdahl limit i.e. M/R ≤ 4/3 (≈ 0.444). We explore the physical characteristics based on the analytical model developed for relativistic compact stellar spheres inside the framework of the general theory of relativity. The evaluated mass and radius are in close concurrence with the observational information. We show that various physical characteristics of the known strange spherical object, viz.

International audienceAluminum, iron, mercury, lead, copper, cadmium, chromium, zinc, manganese, and nickel concentrations were determined in surface and core sediment samples collected in the Loukous estuary (Atlantic Coast, Morocco) to evaluate their levels and spatial distribution. For various metals, the enrichment factor was calculated as a criterion to assess whether their concentrations represented contamination levels or could be considered background levels. Analytical results were processed using Geographical Information System software to show areas of metal accumulation. Using multivariate statistical analysis, the possibility of distinguishing the sampling stations in relation to their geographical position was evaluated. The radiolead (210Pb) and cesium 137 (137Cs) profiles in sediment core retrieved from the Loukous estuary were used to study the temporal variations in sedimentation rate and to reconstruct historical trends of heavy metal input and the effects of human activities. The results show that the distribution of metals in the Loukous estuary is principally influenced by industrial and urban wastes located mostly in the northern coastal area. Marine currents are additional factors influencing metal accumulation in sediments

The thermal quantum correlations in a two-qubit one-dimensional XXZ Heisenberg spin- chain subjected to an inhomogeneous magnetic field are investigated. The concurrence, as thermal entanglement quantifier, and the discord-like quantifiers, namely the trace distance discord and local quantum uncertainty, are computed. Their dependence on the anisotropy parameter γ, uniform magnetic field B, coupling constant J and nonuniform magnetic field b are presented in detail. The mentioned quantifiers behaviors in terms of this parameters are compared and discussed. The results show that TDD is always much stronger than the concurrence and LQU, whereas the latter two show a swinging behavior depending on system parameters. Also, we have shown that the nonuniform magnetic field can reduce the effects of temperature on thermal correlations. Furthermore, the thermal correlations, for fixed values of b, can be enhanced in the antiferromagnetic system in comparison to the ferromagnetic one. In addition, the quantum correlations amounts in the ferromagnetic system are deteriorated when γ decreases, but they are improved when the system is antiferromagnetic.