The Pt3Ni(111) surface has an unusual electronic structure ( d -band center position) and arrangement of surface atoms in the near-surface region. Moreover, fine tuning the composition of the near surface with high-index facets can further improve the ORR activity and stability of the catalyst. If heat transfer through conduction in the snow is insufficient to balance with surface losses, the subsurface snow can warm significantly, inducing near-surface temperature gradients. https://doi.org/10.1016/j.coldregions.2006.08.023. Location: Paradise Divide Area Date of Observation: 11/09/2015 Name: Nick Schley Subject Surface Hoar, Near Surface Facets, And Crusts Elevation: 9,000-12,000ft Avalanches: One R2, D1, Avalanche on Augusta’s NE arm, Crown height ~30cm appeared to… At the surface, a 5 inch layer of near surface facets were prevalent in wind protected open areas below treeline. For full functionality of this site, it is necessary to enable JavaScript. Avalanche Canada. These weak sugary facets were sitting on top of the Dec 12 rain crust. Strong gradient turns rounds to facets. 4.6K likes. ScienceDirect ® is a registered trademark of Elsevier B.V. ScienceDirect ® is a registered trademark of Elsevier B.V. Every minute of every day, the face of Earth changes - sometimes right before our eyes. Hard wind slab at treeline with obvious snow surface texture that we chose to avoid. We toured into Silver Peak today to have a look at rain crusts in the snowpack in the 7,000' to 8,000' range and to see ridgetop wind slabs. The facets were sampled following an updip fault transect (see the Supplemental Material). Technology constantly evolves though, and the emergence of high-precision, low-cost scanning and 3D printing have made facet data more valuable in engineering workflows. In particular, large temperature gradients and associated vapor pressure gradients can occur near the surface when absorbed solar radiation is coupled with cooling effects from longwave radiation and turbulent fluxes. Weak gradient turns facets back to rounds. At the surface, a 5 inch layer of near surface facets were prevalent in wind protected open areas below treeline. Surface hoar up to 10mm in size was observed in large open areas low on the peak. The supercell volume and shape containing the slab in vacuum was then fixed. Written Report: I have just a few observations to pass along from my day of touring at Tam Rim today. Observation Date & Time or Estimated Date & Time of Avalanche: Description of Snow, Weather, and Avalanche Conditions. 2f–h), while highly strained arrangement of atoms is observed near the surface (denoted as ‘D’, extracted from the white dotted box in Fig. Copyright © 2006 Elsevier B.V. All rights reserved. Here are the instructions how to enable JavaScript in your web browser. Under operating conditions relevant to fuel cells, its near-surface layer exhibits a highly structured compositional oscillation in the outermost and third layers, which are Pt-rich, and in the second atomic layer, which is Ni-rich. To better understand the dominant factors, a thermodynamic model was used to extrapolate from the experimental results. The PDEs are believed to be valid away from macroscopically flat surface regions known as “facets”. With no overlying slab at this time, this was not a current stability issue. We toured up Stoney Ridge today to look for buried surface hoar and for general snowpack mapping and monitoring. These radiance profiles were inverted to retrieve daily averaged mesospheric OH densities … Surface hoar became progressively smaller to absent as we ascended the peak. The process in reverse, however, occurs much slowly because it takes so much energy to create a faceted crystal that when we take the energy source away (the strong temperature gradient) it take a lot of time for the crystal to return to its equilibrium state (rounds). This paper focuses on the first process, radiation-recrystallization (shown schematically in Figure 1) in which short (solar) and long (IR) wave radiation promote strong temperature gradients in the near-surface layer. During the subsequent period of time (70 to 100 s), both {110} and {111} facets continue to grow with a similar growth rate until the {110} facets reach the limiting point defined by the two neighboring {100} facets. Such conditions are often formulated within the continuum frame- work [2,11,22,36,37,39,40] rather than derived directly from steps. The study focused on the significance of radiation exchange and snow density on recrystallization near the snow surface. The USDA is not responsible for any advertising, fund-raising events/information, or sponsorship information, or other content not related to the forecasts and the data pertaining to the forecasts. Imposed boundary conditions led to the formation of facets of varying size at and near the snow surface. The occurrence of these facets can be explained through processes called attrition, erosion, abrasion and abfraction. This layer is worth monitoring for possible burial and problematic weak layer formation. Most pertinently: last night was cold and clear and led to the development of weak snow near the … As verbs the difference between surface and facet is that surface is to provide something with a surface while facet is to cut a facet into a gemstone. As nouns the difference between surface and facet is that surface is the overside or up-side of a flat object such as a table, or of a liquid while facet is any one of the flat surfaces cut into a gem. 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