Mechanically mixed layer

It is stated that formation of various types of layers such as transfer layer, mechanically mixed layers, composite layer, etc., having characteristic composition and surface roughness governs the elevated temperature wear behaviour of metallic materials. Similarly during elevated temperature erosion, metallic erosion, erosion from the composite layer and erosion on the oxide scale are reported. The reported literature on abrasive wear at high temperature is much sparser and hence such layers are not yet found in the literature. The... 

Almost all the investigators have identified the formation of a kind of glazed layer that controls the wear processes. Careful and systematic investigation has classified this glazed layer as a transfer layer, a mechanically mixed layer and composite layers. Formation of these layers depends on the wearing conditions. Each of these layers has characteristic composition and surface roughness. The mechanisms of failure of these layers have unique features. 

Patterson s friend Edward D. Goldberg at the Scripps Institution of Oceanography in La Jolla, California, had tipped him off that one of the best records of the world s climate is embedded in thin layers of glacial ice at high altitudes or near the poles. Snow, dust, and fog deposit chemicals from the atmosphere onto the ice, where they remain undisturbed for thousands of years. As Patterson quickly realized, Only the quiescent ice sheets in the arid, perpetually frozen polar regions of the Earth provide annual layers of precipitation that are undisturbed by percolation and mechanical mixing, that are relatively free of dusts and salts, and also are thin enough to be accessible even when centuries old. ... 

Solubility of an agent will be decreased further if it is dissolved in an immiscible organic solvent or if it is thickened such that it forms a protective layer at the agent/water interface. Addition of solvents or mechanical mixing may be required to overcome insolubility problems. 

Breidenthal, R. E. (1981). Structure in turbulent mixing layers and wakes using a chemical reaction. Journal of Fluid Mechanics 109, 1-24. 

Koochesfahani, M. M. and R E. Dimotakis (1986). Mixing and chemical reactions in a turbulent liquid mixing layer. Journal of Fluid Mechanics 170, 83-112. 

Conventional Systems. In the conventional antifouling compositions, the organotin compound (TBTO, TBTF, TBTC1, TBTOAc) is mechanically mixed into the paint vehicle. When the TBT species is completely soluble in the polymer matrix, factors (a) and (b) become unimportant in most cases. The mobile species is already present its diffusion in the matrix, phase transfer and migration across the boundary layer into the ocean environment may be represented by Figure 2a. When the organotin compound forms a dispersed second phase, rate of its dissolution in the polymer matrix becomes another factor to consider. 

Fig. 12.1 Main structural models of graphene-metal oxide hybrids, (a) Anchored model oxide particles are anchored to the graphene surface, (b) Encapsulated model oxide particles are encapsulated by graphene, (c) Sandwich-like model graphene is sandwiched between the metal oxide layers, (d) Layered model a structure composed of alternating layers of oxide nanoparticles and graphene, (e) Mixed model graphene and oxide particles are mechanically mixed and graphene sheets form a conductive network among the oxide particles. Red metal oxide Blue graphene. Reprinted with permission from [41]. Copyright 2012, Elsevier B.V.

Brown, L., and A. Roshko. 1974. On density effects and large structure in turbulent mixing layers. J. Fluid Mechanics 64 775-816. 

Winant, D., and F. K. Browand. 1974. Vortex pairing, the mechanism of turbulent mixing-layer growth at moderate Reynolds number. J. Fluid Mechanics 63 237-55. 

Strykowski, P. J., and D. L. Niccum. 1991. The stabihty of countercurrent mixing layers in circular jets. J. Fluid Mechanics 227 309-43. 

Figure 16.24 illustrates the vertical transport processes and complex interactions that can occur between urban areas, downwind regions, and the free troposphere (Fast, 1998). Emissions from urban regions into the surface layer can be transported into the mixed layer as well as into the free troposphere by several mechanisms, including venting up mountain slopes due to solar heating of the surface, which creates a chimney effect. As shown in Fig. 16.24, clouds also play a role in these vertical transport processes. 

---