Hydrostatic system

Figure 3.8 Conceptualization of the potential functions in a hydrostatic system and in a simple chemical system, (a) In the unequilibrated hydrostatic system, water will flow from reservoir 2 of higher hydrostatic potential (=gh2, where g is the acceleration due to gravity and h2 is the observable height of water in the tank) to reservoir 1 of lower hydrostatic potential total water volumes (i.e., total potential energies W [ and W2) do not dictate flow. Similarly, benzene molecules move from liquid benzene to the head space in the nonequilibrated chemical system, not because there are more molecules in the flask containing the liquid, but because the molecules initially exhibit a higher chemical potential in the liquid than in the gas. (b) At equilibrium, the hydrostatic system is characterized by equal hydrostatic potentials in both reservoirs (not equal water volumes) and the chemical system reflects equal chemical potentials in both flasks (not equal benzene concentrations).

Each basic system has its specific advantages as well as disadvantages. The hydrostatic system provides stable retention of the stationary phase while it yields relatively low partition efficiency due to a limited degree of mixing. The hydrodynamic system, on the other hand, produces a high partition efficiency in a short elution time while the retention of the stationary phase tends to become unstable due to violent mixing, often resulting in emulsification and extensive carryover of the stationary phase. 

In the early 1970s, the hydrostatic system was quickly developed into several efficient CCC schemes, as shown in Fig. 2 [2]. The development has been made by utilizing the unit gravity (Fig. 2, top) or the centrifugal force (Fig. 2, bottom). 

Table 8.5 ISO 6743-4 1999 Hydraulic fluid classification for hydrostatic systems...

The hydrodynamic system has an advantage over the hydrostatic system in that the rotating coil has no inefficient free space which is completely occupied by the mobile phase and therefore every portion of the coil is considered to be efficient column space. At any portion of the coil, one of the phases forms droplets regardless of the choice of mobile phase. Each droplet becomes an efficient stirrer of the other phase by the violent local oscillation."... 

Considering the rotating coil, what is the advantage of the hydrodynamic system over the hydrostatic system What would be the resolution between two components in this case A 75 mL column was filled with 60 mL of stationary phase the first compound came through with a band width of 3 mL after 25 mL of mobile phase had passed through the column, and the second component had a band width of 4 mL after 40 mL of mobile phase had passed through. 

However, some overpressured traps, such as Kristin (Figs 1 5), with a substantial column of condensate exist in Halten Vest and preservation of petroleum in such high pressure isolated fault-bounded reservoirs is fundamentally no different from a hydrostatic system, i.e. the occurrence of the accumulation simply reflects that the fracture pressure at the given depth is higher than the actual reservoir pressure (cf. general principles discussed in Holm 1996). Thus, Kristin is presently sufficiently deep to avoid the fracture gradient and has also a very thick caprock (cf Figs 4 7). No obviously visible gas chimney exists above Kristin, whilst such is indicated over the Lavrans trap. 

Huebner, J.S., 1971, Buffering techniques for hydrostatic systems at elevated pressures, in G.C. Ulmer, ed.. Research Techniques for High Pressure and High Temperature New York, Springer-Verlag, pp. 123-177. 

The retention of the stationary phase in the separation column is an important parameter to determine the resolution of solute peaks in CCC. Generally, the higher the retention of the stationary phase, the better the separation. In the hydrostatic systems, the retention of the stationary phase is improved simply by reducing the flow rate of the mobile phase. 

Electroactive polymers are expected to organize muscular hydrostats systems, in which the muscle provides both the mechanical support for position control as well as the force for motion. Examples are arms for locomotion (octopus), fins for swimming (cuttlefish) and limbs for manipulation (trimks of elephants, tentacles of squid, arms of cuttlefish, and the tongues of frogs) [186], For the purpose of designing such robots, material properties were examined. The point was the scale effect of its softness. Different from solid materials, soft materials amplify... 

MILNE, A.A. Oil flow and film extent, transient variations in a hydrostatic system, NEL Properties of Fluids Internal Report No76, March 1973. 

The expression (2.15) is universal for hydrostatic systems, irrespective of its change of form during the process a hydrostatic system is a system of gas or liquid where the pressure p is the same in all directions. 

The work done on a hydrostatic system with internal equilibrium pressure p is... 

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