Sequential decay

U is produced when Z38U. the most common isotope of uranium, absorbs a neutron. The subsequent sequential decay process produces 239Pu, a fissionable material that can be used as a fuel in nuclear reactors or as the core material of a nuclear bomb. 1 mol of 2 U equates to 239 g by mass, which is approximately 1/20 of the amount needed to make a nuclear device. 

The excitation profile for two-color 1+1 photoionization of 2,2 -bithiophene seeded in a supersonic helium expansion showed that its two-photon photoionization is significantly enhanced by resonance with the Si state, but the observed dynamics clearly show that the dominant channels for photoionization involve long-lived triplet state into which Si decays (94JPC4990). To fit the observed temporal profiles, sequential decay of Si through two triplet states must be invoked. 

An experimental and computational investigation into the photorearrangement of N-cyclopropylimines to yield pyrrolines (Scheme 122) has shown that the, regiochem-istry and stereochemistry can be understood in terms of a mechanism involving barrierless evolution in three different (S2, Si, and So) singlet states and sequential decay through two different (S2/S1 and S1/S0) conical intersection funnels.183... 

Khandelwal A, Rabideau AJ. Transport of sequentially decaying reaction products influenced by linear nonequilibrium sorption. Water Resour Res 1999 35 1939-1945. 

Some radioactive isotopes undergo sequential decay through a series of intermediate, radioactive daughter isotopes before finally yielding a stable daughter product. (U-Th)/Pb geochronology results from three such decay series — ... 

If time-resolved spectra are required, they can easily be calculated from the recorded sequence of decay curves. Three spectra obtained from the data of Fig. 5.21 are shown in Fig. 5.22. Time-resolved spectra obtained from deconvo-luted sequential decay measurements are presented in [285]. 

From the large number of mathematical models for the transport of transformation products with kinetic reactions that can be considered in the Rockflow system we have chosen a first-order chemical nonequilibrium model to simulate the sorption reaction. It can be described by the governing solute transport equation with rate-limited sorption and first-order decay in aqueous and sorbed phases. This model includes the processes of advection, dispersion, sorption, biological degradation or radioactive decay of the contaminant in the aqueous and/or sorbed phases. Figure 6.1 illustrates the conceptual model for sequential decay of a reactive species. 

Figure 6.1 Conceptual model for sequential decay including sorption processes C— dissolved components, 5 — sorbed components).

EXTKARESONANCES IN DEGENERATE FOUR-WAVE MIXING INDUCED BY SEQUENTIAL DECAY... 

Write a partial decay series for Th-232 undergoing the sequential decays 68. Write a partial decay series for Rn-220 undergoing the sequential decays ... 

Radium is a decay product of uranium-238, which undergoes successive alpha, beta, beta, alpha, and alpha decays. Write the five equations representing this sequential decay. All the beta emissions involve beta-minus particles. 

Multiple-longitudinal-strip position-sensitive detectors are being replaced by double-sided strip detectors [359,428] in this application. These detectors have the potential for smaller detector pixels (higher granularity) and, consequentiy, a reduced random-correlation rate. Digital signal processing allows the observation of shorter sequential-decay intervals, down to 1 ps [429]. 

Since its introduction, RT3D has been used in several studies for simulating the natural attenuation of chlorinated solvents. Ling and Rifai (2007), for example, used MOD-FLOW (to predict the flow field), and RT3D (to simulate the sequential decay reactions of chlorinated solvents) to model natural attenuation with source control at a chlorinated solvents dry cleaner site located in northeastern Texas. 

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