Engulfment

Figure 8 A joint principal coordinate projection of the occupied regions in the conformational spaces of linear (Ala) (triangles) and its conformational constraint counterpart, cyclic-CAla) (squares), onto the optimal 3D principal axes. The symbols indicate the projected conformations, and the ellipsoids engulf the volume occupied by the projected points. This projection shows that the conformational volume accessible to the cyclic analog is only a small subset of the conformational volume accessible to the linear peptide, (Adapted from Ref. 41.)...

POOL FIRE A fire involving a flammable liquid spillage onto ground or onto water, or within a storage tank or treneh. The pool size depends upon the seale and loeal topography. Fire engulfment and radiant heat pose the main risks. 

Burns from heat radiation, or fire engulfment. 

As previously discussed, many, if not most, cases of particles adhering to substrates involve at least one of the contacting materials deforming plastically, rather than elastically. Under such circumstances, it would be expected that the extent of the contact should increase with time and, with it, the force needed to detach a particle from a substrate. Moreover, material flow can occur, resulting in the engulfment or encapsulation of the particles. 

Another manifestation of a time dependence to particle adhesion involves the phenomenon of total engulfment of the particle by the substrate. It is recognized that both the JKR and MP theories of adhesion assume that the contact radius a is small compared to the particle radius R. Realistically, however, that may not be the case. Rather, the contact radius depends on the work of adhesion between the two materials, as well as their mechanical properties such as the Young s modulus E or yield strength Y. Accordingly, there is no fundamental reason why the contact radius cannot be the same size as the particle radius. For the sake of the present discussion, let us ignore some mathematical complexities and simply assume that both the JKR and MP theories can be simply expanded to include large contact radii. Let us further assume that, under conditions of no externally applied load, the contact and particle radii are equal, that is a(0) = R. Under these conditions, Eq. 29 reduces to... 

Gritzo, L. A. et al., 1995, Wind-Induced Interaction of a Large Cylindrical Calorimeter and an Engulfing JRE Pool Fire, Symposium on Thermal Science Engineering in Honor of C. L. Tien, Berkeley, CA, November 14. 

Phagocytosis Process describing the engulfment and destruction of extra-... 

Permit space As defined by OSHA, a confined space that contains a hazardous atmosphere, a material that could engulf an occupant, a configuration that could trap an occupant, or any other recognized safety or health hazard. 

About 500 people were at the campsite at the time of the incident. Deaths, primarily from engulfment in the fireball, totalled 211. 

Such hot spots react instantaneously as localized, constant volume sub-explosions (Urtiew and Oppenheim 1966 Lee and Moen 1980). If the mixture around such a sub-explosion is preconditioned sufficiently to ignite on shock compression, a detonation wave will engulf the entire process of flame propagation. 

The main hazard posed by a BLEVE of a container filled with a flammable liquid, and which fails from engulfment in a fire, is its fireball and resulting radiation. Consequently, Lewis (1985) suggested that a BLEVE be defined as a rapid failure of a container of flammable material under pressure during fire engulfment. Failure is followed by a fireball or major fire which produces a powerful radiant-heat flux. 

Anderson et al. (1975) presents results of an experiment with an unprotected, fully loaded 125-m railroad tank car fully engulfed by fire. Although a BLEVE occurred (after 24.5 minutes of exposure), no data on the resulting fireball were presented. 

Schulz-Forberg, B., B. Droste, and H. Charlett. 1984. Failure mechanics of propane tanks under thermal stresses including fire engulfment. Proc. Int. Symp. on Transport and Storage of LPG and LNG. 1 295-305. 

A liquefied propane tank truck whose volume is 6000 U.S. gallons (22.7 m ) is involved in a traffic accident, and the tank truck is engulfed by fire from burning gasoline. The tank is 90% filled with propane. Assume that all of the propane will contribute to the fireball. Radiation effects are calculated below blast and fragmentation effects for this problem will be calculated in Sections 9.2 and 9.3, respectively. 

Sample problem 9.1.S demonstrated the calculation of thermal radiation from the BLEVE of a tank truck. This 6000-gallon (22.7 m ) tank was 90% filled with propane, and burst due to fire engulfment at an overpressure of 1.8 MPa (18 bar). The resulting thermal radiation was sufficient to cause third degree bums to a distance of 300 to 360 m. 

After a successful test with nitrogen, the vessel is placed in service and filled with propane. An accident occurs in which fire engulfs the vessel. The safety valve of... 

Crown ethers are cyclic polyethers. Larger crown ethers contain a cavity that can partially engulf atomic ions. 18-crown-6 actually binds so tightly that it can extract this ion into benzene from water, driving counterions, like MnOc, into the benzene layer, i.e. 

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