Alpha generation

Piper Alpha generated a huge number of lessons learned, many of which provide the basis for the content of this book. Aside from the development of new safety standards and calculation techniques and the writing of new regulations, one of the most important lessons had to do with intervention. The inventory of gas and oil on a platform such as Piper Alpha is quite low, and an emergency always generates a system blowdown. Had the flow of gas from the other platforms been stopped at once, it is likely that the fire would have burned itself out and the nmnber of fatah-ties would have been limited to those caused by the initial explosion. 

Thermal stabihty of the foaming agent in the presence of high temperature steam is essential. Alkylaromatic sulfonates possess superior chemical stabihty at elevated temperatures (205,206). However, alpha-olefin sulfonates have sufficient chemical stabihty to justify their use at steam temperatures characteristic of most U.S. steamflood operations. Decomposition is a desulfonation process which is first order in both surfactant and acid concentrations (206). Because acid is generated in the decomposition, the process is autocatalytic. However, reservoir rock has a substantial buffering effect. 

Attempts have also been made to reduce the odor associated with the peracid in the home laundry. Use of a precursor that generates the peracid of a fatty acid can result in an objectionable odor in the wash bath (106). This odor is exacerbated by the higher piC of the peracid versus its parent acid resulting in a greater proportion of the peracid in the unionized and therefore less water-soluble form. To mitigate this circumstance, functionalization of the fatty tail typically alpha to the carbonyl has been utilized (112). The modifications include alpha-chloro and alpha-methoxy substituents on the parent acid portion of the precursor ester. 

Figure 4.4 Schematic diagram of the structure of the a/p-barrel domain of the enzyme methylmalonyl-coenzyme A mutase. Alpha helices are red, and p strands are blue. The inside of the barrel is lined by small hydrophilic side chains (serine and threonine) from the p strands, which creates a hole in the middle where one of the substrate molecules, coenzyme A (green), binds along the axis of the barrel from one end to the other. (Adapted from a computer-generated diagram provided by P. Evans.)...

VS alpha-XHi%, control. Ibuit-iree AND OR INHIBIT Minimal cutsets of up to 20 can be generated top-down successive Boolean substitution Path sets Cutsets can be automatically punched uds or online data lor ivITT or SUPERPOCUS IBM )C 760( Ava Arg(- c Center... 

OD -T alpha-lies, control, fault-tree description, failure data AND OR NOT K-of- N Bottom-up modularization and decompo-dtion of fault tree into t>est modular nepresentation Top event probability, time dependence, c s, r rCLs, and Linceitainty Option of not generating minimal cut >ets forquali ing fault ree IBM 360/370 Fortran IV, Available j from Software < enter... 

There is no simple answer to this question, but the exact experimental conditions usually have much to do with the result. Alpha-substitution reactions require a full equivalent of strong base and are normally carried out so that the carbonyl compound is rapidly and completely converted into its enolate ion at a low temperature. An electrophile is then added rapidly to ensure that the reactive enolate ion is quenched quickly. In a ketone alkylation reaction, for instance, we might use 1 equivalent of lithium diisopropylamide (LDA) in lelrahydrofuran solution at -78 °C. Rapid and complete generation of the ketone enolate ion would occur, and no unreacled ketone would be left so that no condensation reaction could take place. We would then immediately add an alkyl halide to complete the alkylation reaction. 

Palladino MA, Bahjat FR, Theodorakis EA et al (2003) Anti-TNF-alpha therapies the next generation. Nat Rev Drug Discov 2 736-746... 

In the present context, a tetramer is a symmetric arrangement of four subunits, which generates K channel. Nearly all known K channels are tetramers of identical or similar alpha subunits often associated with additional beta subunits arranged again in a tetrameric fashion. Some K channels are dimers, but each part of their alpha subunits represents a two-fold repeat of a monomer. 

During the red giant phase of stellar evolution, free neutrons are generated by reactions such as C(a,n) and Ne(a,n) Mg. (The (ot,n) notation signifies a nuclear reaction where an alpha particle combines with the first nucleus and a neutron is ejected to form the second nucleus.) The neutrons, having no charge, can interact with nuclei of any mass at the existing temperatures and can in principle build up the elements to Bi, the heaviest stable element. The steady source of neutrons in the interiors of stable, evolved stars produces what is known as the "s process," the buildup of heavy elements by the slow interaction with a low flux of neutrons. The more rapid "r process" occurs in... 

Such alpha-recoil plays a fundamental role in fractionating the nuclides from one another in the low-temperature environment. During igneous processes, on the other hand, alpha recoil is probably not important in the generation of disequilibria ( °Th, Ra, and Pa). Beattie (1993) pointed out that the time scale of annealing of alpha decay damage at high temperatures was much shorter than the time scale of decay of these nuclides. 

TRU are those containing isotopes, like 241Am and 243Am, that follow uranium in the periodic table and whose half-lives are >20 years. If their level of activity was more than 100 nanocuries of alpha-emitters per gram of waste material (up from 10 nanocuries/g in 1982), the waste could be disposed of by shallow burial. Otherwise, the waste had to be placed in retrievable storage for eventual transfer to a permanent repository. TRUs generally have low levels of radioactivity, generate very little heat, and can be handled by ordinary means without remote control (Eisenbud 1987 Murray 1994). 

Marsal J, Svensson M, Ericsson A, et al. Involvement of CCL25 (TECK) in the generation of the murine small-intestinal CD8alpha alpha+CD3+ intraepithelial lymphocyte compartment. Eur J Immunol 2002 32 3488-3497. 

Polonium was considered a rarity. With beryllium, the alpha emitter generates a strong neutron flux. Used as the detonator in the first atomic bombs. 

Glenn Theodore Seaborg (1912-1999), Albert Ghiorso ( 1915), together with Stanley Gerald Thompson (1912-1967) and Kenneth Street (1920-2006). Generated by bombardment of 242Cm with alpha particles. 

---