Quartz-wind

In this article, we will describe in some detail the fundamentals of the three types of streaming flows associated with the microfluidic applications. First, the quartz wind which corresponds to the one-dimensional compressible flow will be introduced. Second, the Eulerian streaming flow in two-dimensional space will be considered. Kundt s dust phenomenon will also be explained. Finally, we will address the flexural plate wave and its net effect, i.e., the Stokes drift flow. 

One-Dimensional Compressible Flow Model Quartz Wind... 

It should be noted that the term Eq. 10 can be understood as a kind of body force. Lighthill [3] has presented solutimis of this system of equations for the case in which the force Eq. 10 acts as a point source in an infinite space. It is seen that when the viscosity is low enough (at high streaming Re3molds numbers), the flow from the source is like a jet as shown in Fig. 1. This flow is sometimes called the quartz wind. The term acoustic streaming refers to this flow in the case... 

Acoustic Streaming, Figure 1 Acoustic streaming quartz wind generated from a point source of ultrasound... 

Aeolian sands are deposited by wind action, either in dunes or in extensive sheets ( cover sand areas ) Wind action is particularly effective in hot and dry regions such as deserts but sand dunes are also common in (sub)humid regions with sparse vegetation, notably in overgrazed areas and along beaches and fluvial braid plains . The (weathering) history of the parent materials in the source area determines whether the sands are rich in quartz and/or carbonates. 

Earth s crust is a source of particles produced as a consequence of weathering and volcanic activity. Weathering of continental rocks generates terrigenous particles that are carried into ocean via rivers, glaciers, and winds. As shown in Table 13.2, the most abundant mineral types are quartz, plagioclase, and clay minerals. The most abimdant... 

The abyssal clays are composed primarily of clay-sized clay minerals, quartz, and feldspar transported to the siuface ocean by aeolian transport. Since the winds that pick up these terrigenous particles travel in latitudinal bands (i.e., the Trades, Westerlies, and Polar Easterlies), the clays can be transported out over the ocean. When the winds weaken, the particles fell to the sea siufece and eventually settle to the seafloor. Since the particles are small, they can take thousands of years to reach the seafloor. A minor fraction of the abyssal clays are of riverine origin, carried seaward by geostrophic currents. Despite slow sedimentation rates (millimeters per thousand years), clay minerals, feldspar, and quartz are the dominant particles composing the surface sediments of the abyssal plains that lie below the CCD. Since a sediment must contain at least 70% by mass lithogenous particles to be classified as an abyssal clay, lithogenous particles can still be the major particle type in a biogenous ooze. 

Soil Harris and Lichtenstein (1961) studied the volatilization of aldrin (4 ppm) in Plainfield sand and quartz sands. Air was passed over the soil at a wind speed of 1 L/min for 6 h at 22 °C... 

The results presented a variety of evidence for the identity of Ca sources near our rural sampling site. The distribution of mean crustal element concentrations as a function of wind direction in summer and fall, from the streaker data, suggest a combination of road and soil sources. This agrees with a comparison of crustal abundances in aerosols and source materials. The comparison showed that most of the elements examined had abundances in the aerosol that often fell between those characteristic of roads and soil. This was not the case for Si, but Si may be expected to be less abundant in aerosol samples than in bulk surficial materials because of the preponderance of quartz (Si02) in the larger particles. 

The dune sand generally consists of fine well-rounded grains shaped by the action of the wind. It is composed mostly of quartz with small percentages of soft calcareous shell fragments and gypsum pellets (12). 

The flow reactor of Felton et al. (84) samples ambient air with a minimum degree of perturbation (Figure 7). Ambient air is drawn by a sample pump into a quartz tube that faces the prevailing wind. The UV/vis-transparent... 

Quartz is the dominant form in which silica is found in coals, and it is ubiquitous. There is some distinction between clastic grains of quartz introduced by wind or water and authigenic quartz deposited from solutions. Quartz is also a major component of clay and siltstone partings in coal that are of detrital origin. 

Centuries ago, time was measured by the gnomon, the clepshydra, weights and gears (eventually controlled by an escapement), incense sticks, hourglasses, and then finally mechanical clocks, pendula, and self-winding watches (mechanically wound, self-winding, or by now controlled by a quartz crystal oscillator tank circuit). 

Silica may be transferred to the site of silcrete development by wind and/or water. Quartz dust, for example, may be transported considerable distances from desert areas by the wind (Goudie and Middleton, 2001). Similarly, plant phytoliths, sponge spicules and diatoms can be subject to aeolian transport (Clarke, 2003). All other transfers rely upon silica transport in solution as undissociated monosilicic acid, either as the monomer H4Si04 or the dimer H6Si207 (Dove and Rimstidt, 1994). Organic or inorganic complexes may also be formed. 

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