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Preface:

The International Conference Frontiers in Theoretical and Applied Physics |UAE 2017 was organized by the Department of Physics at the American University of Sharjah (AUS) in partnership with the Emirates Mars Mission and Mohammed Bin Rashid Space Center (MBRSC) in Dubai-United Arab Emirates. The conference was endorsed by the American Physical Society (APS), Materials Research Society (MRS), the Institute of Physics (IOP) in the UK, and the International Astronomical Union (IAU)-Office of Astronomy for Development. It was held on the beautiful campus of the American University of Sharjah (AUS) in the United Arab Emirates between 22-25February,2017. The conference was the first international and interdisciplinary physics conference in the region that attracted such large number of world-leading scientists and experts in the fields of atomic, molecular and optical physics, condensed matter and materials science, astrophysics and space science, nuclear and ...

Graphene and topological insulators (TI) possess two-dimensional (2D) Dirac fermions with distinct physical properties. Integrating these two Dirac materials in a single device creates interesting opportunities for exploring new physics of interacting massless Dirac fermions. Here we report on a practical route to experimental fabrication of graphene–Sb ₂Te ₃ heterostructure. The graphene–TI heterostructures are prepared by using a dry transfer of chemical-vapor-deposition grown graphene film. ARPES measurements confirm the coexistence of topological surface states of Sb ₂Te ₃ and Dirac π bands of graphene, and identify the twist angle in the graphene–TI heterostructure. The results suggest a potential tunable electronic platform in which two different Dirac low-energy states dominate the transport behavior.

More than 30% of hydrocarbon reservoirs are reported in carbonates that mostly include evidence of fractures and karstification. Generally, the detection of karstic sinkholes prognosticate good quality hydrocarbon reservoirs where looser sediments fill the holes penetrating hard limestone and the overburden pressure on infill sediments is mostly tolerated by their sturdier surrounding structure. They are also useful for the detection of erosional surfaces in seismic stratigraphic studies and imply possible relative sea level fall at the time of establishment. Karstic sinkholes are identified straightforwardly by using seismic geometric attributes (e.g. coherency, curvature) in which lateral variations are much more emphasized with respect to the original 3D seismic image. Then, seismic interpreters rely on their visual skills and experience in detecting roughly round objects in seismic attribute maps. In this paper, we introduce an image processing workflow to enhance selective e...

By using the Laguerre basis in two and three dimensions, we report the scaling behavior of the bound state energies associated with the Yukawa potential. The energy spectrum crossover phenomenon is shown to exist through the scaling law for bound state energies at different principal quantum numbers and the angular momentum as we approach the continuum. It is found that the bound/resonance phase transitions in and

From the modeling and simulation results of presupernova evolution of massive stars, it was found that isotopes of iron, , play a significant role inside the stellar cores, primarily decreasing the electron-to-baryon ratio ( ) mainly via electron capture processes thereby reducing the pressure support. The neutrinos produced as a result of these capture processes are transparent to the stellar matter and assist in cooling the core, thereby reducing the entropy. The structure of the presupernova star is altered both by the changes in and the entropy of the core material. Here we present the microscopic calculation of Gamow–Teller strength d...

Although arterial embolism is important as a major cause of brain infarction, little information is available about the hemodynamic factors which govern the path emboli tend to follow. A method which predicts the trajectory of emboli in carotid arteries would be of a great value in understanding ischemic attack mechanisms and eventually devising hemodynamically optimal techniques for prevention of strokes. In this paper, computational models are presented to investigate the motion of a blood clot in a human carotid artery bifurcation. The governing equations for blood flow are the Navier–Stokes formulations. To achieve large structural movements, the arbitrary Lagrangian–Eulerian formulation (ALE) with an adaptive mesh method was employed for the fluid domain. The problem was solved by simultaneous solution of the fluid and the structure equations. In this paper, the phenomenon was simulated under laminar and Newtonian flow conditions. The measured stress–strain curve obtained fr...

The occurrence of a bottom simulating reflector (BSR) in the 2D seismic data from Makran's accretionary prism reveals the presence of gas hydrate and free gas several hundred meters below the seafloor of Iran's deep sea. According to the global distribution of marine hydrates, they are widely present in deep sea sediments, where high operational costs and hazards cause a lack of well log information. Therefore, developing a method to quantify the hydrate resources with seismic data is an ultimate goal for unexplored regions. In this study, the so-called reflectivity templates (RTs) are introduced for quantification of the hydrate and free gas near the BSR. These RTs are intuitive crossplots of P-impedance and S-impedance contrasts across the BSR. They are calculated theoretically based on the effective medium theory for different hydrate distribution modes with some assumptions on porosity and mineralogical composition of unconsolidated sediments. This technique suggests the poss...

The effects of an axial magnetic field on the convective amplification and the threshold intensity of Raman backscattering instability in an underdense, inhomogeneous plasma is investigated. Two cases of incident pump wave were considered. For the R-circularly polarization case it is shown that the amplification factor increases with the magnetic field, it also increases with the plasma density while the threshold intensity decreases. For the L-circularly polarization case, it is shown that the amplification factor decreases as the magnetic field and the plasma density increase, while the threshold intensity increases as the magnetic field increases but it decreases as the plasma density increases.

The permittivity of BaTiO ₃ doped with small concentrations of Gd ₂O ₃ (0.01 approximately 0.1 mol.%) are found to be remarkably dependent on the type of the solid solution formed between Gd ₂O ₃ and BaTiO ₃. The decrease of permittivity at the Curie peak with decreasing grain size for BaTiO ₃ doped with concentrations of Gd ₂O ₃ from 0.5 approximately 3 mol.% is attributed to the formation of defective non-ferroelectric grain boundary layers of low permittivity.