Stand-still condition

Mass transfer measurements using an electrochemical probe are still under investigation. They only allow local measurements and the system accuracy is not yet known. These methods do however allow interesting observations on acoustic streaming and standing waves conditions. 

In the previous section it was noted that, for components A and B to stand still in presence of the nonuniform mean stress field, the concentration of A needs to be higher at the east point now we see that the concentration at the east point needs to overshoot this condition a little if it is to drive the fluxes that accompany the change of phase. But, of course, if the chemical relation were of the opposite kind, with the host having higher A B ratio in equilibrium, the retreating interface at the east point would absorb A, the concentration of A there would be a little less than the concentration for static balance, and there would be a small flux of A toward the east point. 

If we choosel the ground as our frame of reference, then the velocity of the air relative to the ground is zero, so we conclude that the reservoir condition is 0°C = = 273.15 K and 50kPa. However, this would be a very impractical choice if we wished to analyze the performance of the airplane. We would rather choose a coordinate system based on the airplane. In such a case, the air is moving at Jt = 2 toward the plane, so it is certainly not standing still and hence not in its reservoir state. To find the reservoir temperature, we may slow the air down to zero velocity relative to the airplane by an adiabatic device and then measure its temperature. From Eq. 8.16 we see that the reservoir temperature is... 

We might also think about this problem in another way. Suppose we want to test the airplane]standing still in a wild tunnel. We want the air to come in at M = 2 at 0 C and 50 kPa. What must be the conditions in the reservoir of the... 

Several points are noteworthy. First, the velocity vector at every location of the liquid points mainly in the x-direction. As a result, it is legitimate to reduce the Navier-Stokes equation to its v-component along the direction of the flow, thereby replacing the original three-dimensional vector equation with a much friendlier scalar counterpart. Second, the boundary condition at the solid/liquid interface demands that the velocity be continuous. Since the solid is fixed, it stands to reason that the liquid in its immediate vicinity must stand still as well. This restriction has two consequences ... 

The characteristics of coastline response to SLR suggested by the Bruun rule seem conceptually correct. However, under present near-stUl-stand SLR conditions, the Bruun effect can easily be subordinate to a host of other processes. Therefore, any good comparisons between shoreline recessions measured in the last century under near-still-stand SLR and corresponding Brmm rule predictions are likely to be fortuitous and cannot be considered as conclusive verification of the Bruun rule. Furthermore, due to the many restrictive assumptions associated with the Bruun rule, it is not applicable in most natural environments, as exemplified by the exclusion by Zhang et al. of almost 70% of the study area from their analysis. The applicability of the Bruun rule is particularly compromised in the vicinity of tidal basins associated with inlets as the Bruun effect can be overridden when the basin area is larger than fOkm. ... 

Occlusion, or blocking, of the coronary circulation is usually caused by extensive atherosclerosis and/or a blood clot lodged in an artery. Occlusion is likely to occur in the coronary system before it does in other major arteries because, during the heartbeat, there is a moment when the blood literally "stands still" in these arteries. This condition occurs because each contradion of the heart muscle squeezes the coronary arteries and temporarily stops the forward flow of blood in them. The flow of blood in these arteries resumes when the muscle relaxes between contradions. Slowing of the movement of blood favors the development of such obstrudions as atherosclerotic deposits and clots, when other conditions are also favorable for these developments. 

The analysis showed the high influence of the weather on the maintenance logistics. Both the trip duration and the accessibility of the turbine depend on the weather condition. The effect of sudden failures on the availability is higher compared to maintenance actions, as the turbine stands still until the spare part is available and the repair is finished. 

Although the process as it stands is still not enantioselective in nature, the high yield and mild reaction conditions may attract further search for an asymmetric version of this reaction using proper chiral bromine-comtaining compounds as the catalyst. 

One cyano group of 59 is replaced under very mild conditions. For example, 2-methoxy-3,5,6-tricyanopyrazine (98) is formed in nearly quantitative yield when a solution of 59 in methanol is allowed to stand at room temperature for 2 hr. The reaction with better nucleophiles such as anilines is so exothermic that the temperature must be controlled by cooling or addition rate. Good yields of the monodisplacement products 99 are easily obtained. Still better... 

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