In this work a method of straight lines for a Bingham problem in cylindrical geometry is developed. A Bingham fluid has viscosity properties that produce a separation into two regions, a rigid zone and a viscous zone. We propose a method of lines with the time as a discrete variable. We prove that the method is well defined for all times, a monotone property, qualitative behaviours of the solut...

Fibonacci zone plates are proving to be promising candidates in image forming devices. In this letter we show that the set of Fibonacci zone plates are a particular member of a new family of diffractive lenses which can be designed on the basis of a given m-bonacci sequence. These lenses produce twin axial foci whose separation depends on the m-golden mean. Therefore, with this generalization, ...

High-resolution angle-resolved photoelectron spectroscopy is used to examine the electronic band structure of FeTe_{0.5}Se_{0.5} near the Brillouin zone center. A consistent separation of the α_{1} and α_{2} bands is observed with little k_{z} dependence of the α_{1} band. First-principles calculations for bulk and thin films demonstrate that the antiferromagnetic coupling between the Fe atoms ...

This article addresses the problem of contact voltage increase caused by low-frequency oscillation train-grid system in phase-separation process EMUs. The establishes EMU-contact line-traction substation model, reveals mechanism oscillation, and ascertains relationship between phase angle when pantograph leaves line, oscillations. Methods to suppress overvoltage during are proposed. research in...

In the present work, CdSe nanocrystals (NCs) synthesized with a trioctylphosphine surface passivation layer were modified using amphiphilic molecules to form a surface bilayer capable of providing stable NCs aqueous solutions. Such modified nanocrystals were used as a test solute in order to analyze new electrophoretic phenomena, by applying a micellar plug as a separation tool for discriminati...

A non-destructive replica method and a 3-D reconstruction algorithm are used to analyse the geometry and expansion of the shoot apex surface. Surface expansion in the central zone of the apex is slow and nearly isotropic while surface expansion in the peripheral zone is more intense and more anisotropic. Within the peripheral zone, the expansion rate, expansion anisotropy, and the direction of ...