Fission, cell probability

Exercise. The neutrons in a nuclear reactor behave as free particles until they are absorbed, scatter, or cause fission and thereby produce more neutrons. The master equation for the joint probability distribution of the occupation numbers nk of the phase space cells X is... 

Distribution ratios and transport were carried out on real HAW arising from dissolution of a mixed oxide of uranium and plutonium (MOX) fuel (burnup 34,650 MW d/tU), where uranium and plutonium have been previously extracted by TBP.86 The experiments were performed in the CARMEN hot cell of CEA Fontenay aux Roses with two dialkoxy-calix[4]arene-crown-6 derivatives (diisopropoxy and dini-trophenyl-octyloxy). High cesium distribution ratios were obtained (higher than 50) by contacting the HAW solution with diisopropoxy calix[4]arene-crown-6 (0.1 M in NPHE). Moreover, the high selectivity observed with the simulated waste was confirmed for most of the elements and radionuclides (actinides or fission products Eu, Sb, Ce, Mo, Zr, and Nd). The residual concentration or activity of elements, other than cesium, was less than 1% in the stripping solution, except for iron (2%) and ruthenium (8%) the extraction of these two cations, probably under a complexed... 

The question to answer is given an initial population size jr(0) = Xo, and certain information about the probability of cell fission, what is the probability, that X t) = x for t>0 Clearly, the question can be... 

At this point, models must be introduced for the fission and washout processes. If we assume that the vessel is perfectly mixed, then washout probability (P(E BC)) is independent of cell age, and moreover... 

Inspection of Rahn s model can also clarify this point. Consider a cell formed by fission at time. At time Iq + this cell will have age t. By Rahn s hypotheses, the probability of replication of one gene in time interval Iq + to + + given that x genes have been replicated at time to + is... 

If P = pf is the probability that a neutron in cell j will produce a neutron in cell i after a specified time (or event such as collision or fission), then the expected neutron population in cell i after the (r -f- l)st such event will satisfy... 

The unit-cell method offers a relatively simple computational procedure for determining the various factors in /c . As already demonstrated, the calculation of these factors in each case reduces ultimately to the determination of the neutron spatial distributions for the entire energy range. For the thermal utilization we require the thermal-flux distribution and in particular the thermal-flux depression (i.e., the thermal disadvantage factor). The resonance-escape probability, on the other hand, requires a knowledge of the spatial distribution of resonance neutrons, and finally, of course, the calculation of the fast effect involves, essentially, the determination of the spatial distribution of successive (cascading) generations of fission neutrons. 

Benzene, This simplest aromatic compound is utilized by a variety of bacteria as the sole source of carbon and energy in a mineral salts solution (Beerstecher, 1954, p. 189). In the rabbit and the human several hydroxylated intermediates have been identified (Porteus and Williams, 1949) phenol, 1,2-dihydroxybenzene (catechol), 1,4-dihydroxybenzene (quinol), and 1,2,4-trihydroxybenzene (hydroxyquinol). In bacteria, the fissioned ring product has been isolated as trans,trans-m xcomc acid (Kleinzeller and Fend, 1952 Wieland et al., 1958). Catechol is the probable immediate precursor of muconate, this conversion having been demonstrated repeatedly by (1) isolation of muconic acid, (2) simultaneous adaptation studies, and (3) experiments with the cell-free, ferro-enzyme pyrocatechase (Hayaishi and Hashimoto, 1950 Evans and Smith, 1951 Evans et al., 1951 Stanier and Ingraham, 1954). Two atoms of oxygen are added per molecule of catechol. Hayaishi and co-workers (1955) have shown by means of experiments with and and... 

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