Inner pressure

Figure 21 shows the large coater for the VIRGO optics at LMA (Lyon). The technology is DIBS. Its size is 2x2.2x2.2 m. The inner pressure is 2 x 10 mBar. The coater is located in a 150 m class 1 room whith metrology and control. In a class 1 room, tolerance is <10 particles of 0.1 jum and <1 particle of 0.5 /xm xfoot xs l. 

A large filter area is recommended. A 1-cm layer of Celite is pressed on a sintered-glass funnel (6 cm x 17 cm). The Celite is dried in an oven at 120°C for 12 hr. A 6-mm Teflon tube is used to connect the flask and the filter funnel through the septa, and the stirred slurry is then transferred to the funnel with the aid of nitrogen pressure. Inner pressure of the receiver flask and the funnel Is leaked through oil bubblers. The... 

C = Contact surface air/air, initial inner pressure 115 psi, temP 297°K (1) atm external to cylinder (4) = interior region of cylinder... 

Pump or compressor may be required for unloading depending on inner pressure of transportation device... 

Figure 2.4 Rubber membrane at the end of a cylindrical tube. An inner pressure Pi can be applied, which is different than the outside pressure Pa.

I Procrastination creates inner pressure. Those who delay continue to carry the problem with them. Those who design a plan release these pressures and enjoy life more. 

In order to prepare and clarify a polymer solution at a temperature higher than 200 °C, two different apparatuses were developed [30,33]. Importantly, they are able (1) to dissolve a polymer under an inert atmosphere without losing solvent and without building up inner pressure due to solvent evaporation, and (2) to transfer the solution into a filtration device by a remote control. 

BLAST FROM A 2" DIAM PRESSURIZED SEALED GLASS CYLINDER G = Sealed end glass cylinder 2)4" long F = Glass fragments S, = Main shock wave Sj = Second shock wave H - Head of rarefaction wave C Contact surface air/air, initial inner pressure 115 psi, temP 297°K (1) = atm external to cylinder (4) interior region of cylinder... 

When two bubbles come into close contact in the liquid medium, the shape of the film formed depends on the bubble size and, respectively, on the excess (inner) pressure in them. This has been already considered in details by Plateau [8,54], Fig. 1.8 shows the contact between two bubbles. If the bubble sizes and pressures in them are not equal R) < R2, p >P2) the foam film which separates them bends turning its convex surface towards the bubble with bigger radius (with the lower pressure). The radius of curvature of the separating film Ri is determined by the expressions... 

In the van der Waal s equation of state for real gases, the interaction energy of the molecules is represented by the term a. The interaction of the molecules produces the so-called inner pressure given by the term aj V, The work done in overcoming this attraction will be... 

The two strain components are computed separately. First the pressure-induced component It can be shown that a thin cylindrical shell of radius r, thickness d, and elastic modulus E, subject to inner pressure Ap, undergoes strain given by... 

Once the cure temperature distributions and stresses have been calculated, the stresses at various operating and shutdown conditions can be easily computed using formulas (13) to (24) by viewing the conditions simply as changes in temperatures and inner pressure. 

Materials that have to be used in the km3 detector construction must resist to an extremely hostile environment where pressure ( 300 bar at 3000 m depth), together with salinity, reduce the lifetime of most metals and alloys used in surface and shallow water applications. NEMO is designing and realising underwater vessels (junction boxes and other submarine containers) decoupling the two problems an outer vessel, made of glass epoxy, resistant to marine corrosion is filled with not-corrosive oil. The inner pressure resistant vessel, made of common steal and pressure resistant, will host fragile electronic components. Another crucial point for deep sea detectors installation is feasibility and reliability of underwater connections. NEMO is studying the possibility to... 

In conclusion, we observe that to justify the suggested problem setting, one has to add the assumption of a flat free surface. Actually, the normal stress on the liquid surface prove to be variable in our cases, which will result in a distortion of the surface. But this effect is absent at large g, when any inner pressure is neutralized by an infinitesimal change of the surface shape. 

Reagent containers should preferably have a cap in order to avoid contamination of the laboratory environment by volatile chemical compounds and/or contamination of the solutions to be pumped. An orifice for maintaining the container inner pressure during solution pumping is then required. 

Thus, for a ratio for d/D of 1 2 and for an inner pressure of 1 GPa, the pressure at the window-seat interface is 1.33 GPa and the overpressure which opposes the leak is 333 MPa. In the same way as the Bridgman seals described in Section 1, increasing the pressure will tend to reduce leaks. Another advantage of the Poulter geometry is that the window material is subjected to the hydrostatic pressure it is meant to contain. This enhances its mechanical properties since the elastic coefficients of solids usually increase under high pressures. 

The input feed stream is composed of an effluent gas (argon) and one of the hydrogen isotopes, H or D, at a time. The output species from reactor were monitored by the mass spectrometer, with a constant inner pressure of 6 x 10 torr. The gases used in all experiments are of ultra high purity (min 99.99 % voL). 

In general, the vessel will be tight if the seal pressure (p ) is higher than the inner pressure (pi). Various closure designs have been made to provide the needed seal pressure [21-25]. 

Boiling Liquid Expanding Vapor Explosion (BLEVE) characterizes the failure mechanism of a liquid gas container where the major part of the contents are released by flash vaporization and explode while the remainder forms a pool which bums down. Three conditions need to be met (i) the liquid is supeiheated, (ii) a sudden pressure drop occurs, (iii) pressure and temperature conditions are such that flash vaporization is possible. This type of explosion is caused if a storage tank is exposed to a heat source from outside. A tank stmcture weakened by the high temperatures, a high inner pressure, and tensions in the container wall near the gas / liquid boundary layer eventually results in the catastrophic failure, however, merely causing pressure waves. An intact safety valve could delay, but possibly not prevent the vapor explosion [73]. 

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