The Bull

Figure 2.2. Shock wave in a freight train resulting from impact between the cowcatcher and bull. In this case, the bull is infinitely massive.

Expansion waves are the mechanism by which a material returns to ambient pressure. In the same spirit as Fig. 2.2, a rarefaction is depicted for intuitive appeal in Fig. 2.7. In this case, the bull has a finite mass, and is free to be accelerated by the collision, leading to a free surface. Any finite body containing material at high pressure also has free surfaces, or zero-stress boundaries, which through wave motion must eventually come into equilibrium with the interior. Expansion waves are also known as rarefaction waves, unloading waves, decompression waves, relief waves, and release waves. Material flow is in the same direction as the pressure gradient, which is opposite to the direction of wave propagation. 

Where 90° turns in piping are required, standard long radius ells (ell centerline radius equals 1.5 times pipe nominal diameter) are usually used. In sandy service, the sand has a tendency to erode the metal on the outside of the bend. Target tees, such as shown in Figure 15-25, are often specified for such service. The sand builds up against the bull plug and provides a cushion of sand that is constantly being eroded and subject to deposition by the sand in the flow stream. 

Sangria means bleeding in Spanish. Don t run with the bulls when you make it. 

A review article is an intensive survey of a rather narrow field for example, the titles of some recent reviews are Desulfonation Reactions Recent Developments , Pyrrolizidine and Indolizidine Syntheses Involving 1,3-Dipolar Cycloaddtion , and From Corrin Chemistry to Asymmetry Catalysis—A Personal Account. A good review article is of enormous value, because it is a thorough survey of all the work done in the field under discussion. Review articles are printed in review journals and in certain books. The most important review journals in organic chemistry (though most are not exclusively devoted to organic chemistry) are shown in Table A.3. Some of the journals listed in Table A.l, for example, the Bull Soc. Chim. Fr. and J. Organomet. Chem. also publish occasional review articles. 

Figure 1. Isopleths of krlglng estimation variances. (The bull s-eyes reflect the data locations.)...

Contrariwise, conservationists have argued that no foreign substances should be discharged into the air and waters. These are natural resources and should be kept pure. The loggers who are using horses in the Bull Run Reservoir area near Portland, Ore., are required to diaper their horses to protect the water quality. What about wild animals such as deer They, like all the other plants and animals, excrete wastes. Often it seems that conservationists consider that it is only man, his domestic animals, factories, and machines that pollute. Purity implies wastes only from natural sources. ... 

Gerena, R. L et al (2000b). Immunocytochemical localization of lipocalin-type prostaglandin D synthase in the bull testis and epididymis and on ejaculated sperm. Biol. Reprod. 62, 547-56. 

Thus for an x-wave (l = 0), which corresponds to hitting the bull s eye and so usually dominates unless forbidden by selection rules or upstaged by a resonance, the total cross-section (of which the major component is normally elastic scattering) is given by... 

R = the normal reaction of the bull ring on the grinding head. 

Vulval skin secretion and blood serum contain an active principle, which attracts the bull and releases smelling, salivating, urinating, licking, flehmen, vocalizations, penis protrusion, and mounting. It is not clear whether the blood transports the active principle to or from the vulval skin tissue (Rivard and Klemm, 1989). 

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