Water surface burst

Detonations of the second category—those which produce particles by condensation from the vapor state—include airbursts and water surface bursts. 

Water Surface Burst. When the entire platform of a water surface detonation is vaporized, the primary particle population is exactly like that described under airburst. However, the particles of the primary population act as condensation nucleii for the late-time condensation of sea salts. The salt particles are hygroscopic and eventually dissolve and leave the primary population behind. However, particle transport is affected by the sea salt particle growth which temporarily, at least, produces larger particles than does an airburst. 

The results of correlation studies reported in Refs. 2, 4, and 7 indicated that the fractionation behavior of most fission products was remarkably similar for coral surface bursts, bursts on the surface of deep and shallow seawater, and bursts at altitudes sufficiently great to avoid entrainment of soil or water in the fireball and cloud. Furthermore, the correlations showed no clear-cut dependence on the explosive yield of the device. This report extends the treatment to a near-surface event on silicate soil. 

B. Surface Burst. A surface burst weapon is detonated on or slightly above the surface of the earth so that the fireball actually touches the land or water surface. The area affected by blast, thermal radiation, and initial nuclear radiation will be less extensive than for an air burst of similar yield, except in the region of ground zero where destruction is concentrated. In contrast with airbursts, local fallout can be a hazard over a much larger downwind area than that which is affected by blast and thermal radiation. 

C. Subsurface Burst. A subsurface burst weapon is detonated beneath the surface of land or water. Cratering will generally result from an underground burst, just as for a surface burst. If the burst does not penetrate the surface, the only other hazard will be from ground or water shock. If the burst is shallow enough to penetrate the surface, blast, thermal, and initial nuclear radiation effects will be present, but will be less than for a surface burst of comparable yield. Local fallout will be very heavy if penetration occurs. 

Both high bulk and surface shear viscosity delay film thinning and stretching deformations that precede bubble bursting. The development of ordered stmctures in the surface region can also have a stabilizing effect. Liquid crystalline phases in foam films enhance stabiUty (18). In water-surfactant-fatty alcohol systems the alcohol components may serve as a foam stabilizer or a foam breaker depending on concentration (18). 

Liquid water, including its soluble and insoluble constituents, is transferred from the oceans to the atmosphere when air bubbles in the water rise to the surface. These bubbles form from air trapped by breaking waves, "whitecaps." As the bubbles burst at the surface, water droplets are injected into the atmosphere. These water droplets are small enough to remain airborne for several hours. Whitecaps begin to form in winds common over the oceans, and a significant amount of seasalt made airborne in this way is transported to the continents and deposited in coastal areas. 

The amount of exogenous drug is difficult to determine. Before conducting release experiments, loaded halloysite was always washed with a large amount of water during a 5 minute rinse to ensure removal of material from the surface. However, we cannot exclude some of the active agent being attached to the outer surface of the halloysite, especially in the natural gap-defects on the cylinder surface at the end of the rolled clay sheet (it is a natural pocket on the tubule surface). The typical 5-10 % initial release burst we observed may be related to dissolution of this material. 

The majority of the aforementioned capsules were either not sufficiently mechanically stable or suffered from other surface or matrix related deficiencies. These deficiencies include poor morphology, such as capsule sphericity and surface smoothness, which result from an osmolar imbalance. Membranes are also often leaky (an internal polymer slowly diffuses out through the capsule wall) or shrink in either PBS or in culture media over a period of a few hours. Exceptionally, some capsules are observed to swell excessively and burst. Furthermore, some complex membranes, although stable in water, dissolve over several days upon a contact with culture media. This is true for pectin based capsules (pectin/calcium salt) and for alginate-chitosan membranes and maybe a consequence of the polycation substitution by electrolytes present in the media [10]. In order to improve the existing binary capsules several approaches, both traditional and novel, have been considered and tested herein. These are discussed in the following sections. 

Additional information resulted from an array of burst discs set 70 cm below the water surface in the central area of the tank. 

The major ions are transported across the air-sea interface by the ejection of water droplets from the sea surfece. These droplets result from water turbulence at the sea surface that causes microscopic bubbling. Some of these bubbles burst, ejecting seawater into the atmosphere. Since not all of the salt ions are ejected to the same degree, bursting bubbles can alter the ion ratios in the remaining water. 

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