Pocket bubble

Gas (or Yapor) Pockets (Bubbles) in Liquid and Solid Explosives. 

Substantially different fracture modes are observed between aged tritium-loaded and unloaded steel specimens. Helium-3 is vastly less soluble in metals than is hydrogen (tritium) helium pockets (bubbles) form with high internal pressures. Hydrogen embrittlement also contributes to this effect. 

Pocket bubble Figure 1.3 Two types of blown film bubbles... 

A distinction is often made between two general types of bubble shapes (Fig. 3.9) that are selected by the processor for a given resin type. The pocket bubble has little or no stalk, beginning its expansion almost immediately above the die face. This... 

Figure 3.9 Pocket bubble on left and high (long) stalk bubble on right (The Blown Film Extrusion Simulator)...

Successive reflections of the pressure wave between the pipe inlet and the closed valve result in alternating pressure increases and decreases, which are gradually attenuated by fluid friction and imperfect elasticity of the pipe. Periods of reduced pressure occur while the reflected pressure wave is travehng from inlet to valve. Degassing of the liquid may occur, as may vaporization if the pressure drops below the vapor pressure of the liquid. Gas and vapor bubbles decrease the wave velocity. Vaporization may lead to what is often called liquid column separation subsequent collapse of the vapor pocket can result in pipe rupture. 

Air can also enter into the pump from bubbles and air pockets in the suction piping. 

In cold climates, many homes and businesses use double and triple pane tows. The air pocket between double and triple pane windows serves to insulate so that heat is not lost through the windows. Likewise, air bubbles in oil prevent the heat from escaping. 

A vapor poeket on the exchanger s low-pressure side can create a cushion that may greatly diminish the pressure transient s intensity. A transient analysis may not be required if sufficient low-pressure side vapor exists (although tube rupture should still be considered as a viable relief scenario). However, if the low-pressure fluid is liquid from a separator that has a small amount of vapor from flashing across a level control valve, the vapor pocket may collapse after the pressure has exceeded the fluid s bubble point. The bubble point will be at the separator pressure. Transient analysis will prediet a gradually inereasing pressure until the pressure reaches the bubble point. Then, the pressure will increase rapidly. For this ease, a transient analysis should be considered. 

Luft-bestandigkeit, /. stability in air, resistance to air. -bestandteil, m. constituent of air. -bild, n. aerial photograph (Optica) aerial image, -blaschen, n. (small) air bubble, -blase,/, air bubble air pocket air bladder, -bleiche, /. open-air bleaching, -bombe, /. aerial bomb, -brennstoffgemisch, n. fuel-air mixture. 

Air pockets or bubbles are left on the surface of all concrete. Good vibration and placing techniques will reduce their number but not eliminate them. Many air pockets have a small opening on the surface in relation to their size. Paints will not penetrate into such holes, with the result that air or solvent is trapped and subsequent expansion will cause the coating to blister. In addition, some air pockets are covered with a thin layer of cement that also has no strength and will cause loss of adhesion. 

Very popular is plastic cushioning material used in packaging, usually laminated thermoplastic films that incorporate air bubble pockets. 

The structure of whipped cream is quite complex. A coating of milk protein surrounds small globules of milk fat containing both solid and liquid fats. These globules stack into chains and nets around air bubbles. The air bubbles are also formed from the milk proteins, which create a thin membrane around the air pockets. The three-dimensional network of joined fat globules and protein films stabilizes the foam, keeping the whipped cream stiff. 

Plug flow. Plug in horizontal flow, as shown in Figure 3.16, consists of enlongated gas bubbles. Although the name is sometimes used interchangeably with slug flow, it is differentiable in horizontal flow by the shape of the gas cavity or the appearance of staircase hydraulic jumps at the tails of air pockets (Ruder and Hanratty, 1990). 

The pores are the really clever bit of the head. Half-way along each pore is a minute heater surrounded by a small pocket of air. In front of the heater is a small bubble of ink, and behind it is the circuitry of the printer, ultimately connecting the heater to the computer. One such capillary is shown schematically in Figure 1.8. 

Just before the computer instructs the printer to eject a bubble of ink, the heater is activated, causing the air pocket to increase in temperature T at quite a rapid rate. The temperature increase causes the air to expand to a greater volume V. This greater volume increases the pressure p within the air pocket. The enhanced air pressure p is sufficient to eject the ink bubble from the pore and onto the page. This pressure-activated ejection is similar to spitting. 

An air pocket in the pump can cause low or no pressure or flow, erratic pressure, and changes in retention time data. It may be necessary to bleed air from the pump or prime the pump according to system startup procedures. Air pockets in the column will mean decreased contact with the stationary phase and thus shorter retention times and decreased resolution. Tailing and peak splitting on the chromatogram may also occur due to air in the column. Air bubbles in the detector flow cell are usually manifested on... 

Mechanism of Action Anantiflatulent that changes surface tension of gas bubbles, allowing easier elimination of gas. Therapeutic Effect Drug dispersal, prevents formation of gas pockets in the G1 tract. 

FIGURE 1.7 Three typical cellulose fibers adsorbed on the wall of a glass poured with champagne the gas pockets trapped inside the fibers lumen and responsible for bubble formation clearly appear (bar = 100 pm) (Photographs by Gerard Liger-Belair). 

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