wind regime data from the jask meteorological station from a 20-year statistical period (1985-2005) was analyzedusing the fryberger method to investigate sand drift potential (dp) in this area. the resultant drift potential anddirectional variability of wind were calculated and illustrated. average annual sand dp was estimated to be 460vector units (vu), and the sand flux is 51 m3/m.year. there...

In this paper, the effects of horizontal stress and dimensions of barrier pillars on the stability of drifts hr been investigated. An elastoplastic hybrid finite/boundary element program has been used. A plastic analysis of stresses in barrier pillars above the drifts in one of the underground coal mines with inclined seams is examined. Computed stresses and safety factor controur lines around ...

We investigate the validity and failure of Liouville theorems and Harnack inequalities for parabolic and elliptic operators with low regularity coefficients. We are particularly interested in operators of the form ∂t−∆+ b ·∇ resp. −∆+ b ·∇ with a divergence-free drift b. We prove the Liouville theorem and Harnack inequality when b ∈ L∞(BMO) resp. b ∈ BMO−1 and provide a counterexample demonstra...

Introduction: Eolian sedimentary deposits are important because they provide a record of the direction and strength of winds on Mars and the type and flux of sediments transported by the winds. While Martian sand dunes and transverse aeolian ridges ("TARs") have been thoroughly studied, the sedimentary deposits left behind by blowing dust have received comparatively little attention to date. Wi...

[1] All-sky imagers located at Tucumán, Argentina (26.9 S, 65 W, 14.2 S dip latitude), and Arequipa, Perú (16.5 S, 71.5 W, 2.7 S dip latitude), are used to track 630 nm airglow depletion motions in the first use of multisite airglow imagers for studies of low-latitude plasma dynamics. A new image analysis technique yields a consistent determination of nighttime zonal plasma drifts from all-sky ...

A new design for a DRIFTS cell for in-situ studies in heterogeneous catalysis is presented, which allows for improved reaction control (i.e., gas flow, temperature, minimized background conversion) and for precise kinetic measurements. Specifically, the very low background activity of the cell itself for CO and H2 oxidation makes it possible to study the preferential CO oxidation in H2-rich gas...