scholarly journals DECSERVIS: a tool for radioactive decay series visualisation

2006 ◽  
Vol 4 (4) ◽  
pp. 822-834 ◽  
Author(s):  
Saad Azzam ◽  
Juhani Suksi
Keyword(s):  
Initial Conditions ◽  
Radioactive Decay ◽  
Decay Chain ◽  
Decay Series ◽  
Closed Systems ◽  
Natural Decay ◽  
User Friendly ◽  
Interactive Visualisation ◽  
Flexible Operation ◽  
Chain Decay

AbstractWe have developed an interactive visualisation tool, decay series visualisation (DECSERVIS), for exploring the three natural radioactive decay chains. Through DECSERVIS, one can investigate the full decay scheme of any natural decay chain radionuclide to obtain the number of nuclides, their masses, activities, and activity ratios, accounting for all the daughters, starting from initial conditions freely chosen by the user. The tool has been developed particularly for user friendly and flexible operation. Chain decay in closed systems can be explored as a function of time with various graphical presentations such as solid curve and column diagrams or animation. We present several exploration examples related to geological dating. DECSERVIS will be freely available on request.

15.—Natural Radioactive Decay Series Elements in the Oceans and Sediments

1972 ◽  
Vol 72 (1) ◽  
pp. 167-182 ◽  
Author(s):  
J Thomson ◽  
A. Walton
Keyword(s):  
Radioactive Decay ◽  
Decay Chain ◽  
Secular Equilibrium ◽  
Marine Geochemistry ◽  
Daughter Nuclide ◽  
Decay Products ◽  
Naturally Occurring ◽  
Decay Series ◽  
Time Required ◽  
Radio Isotopes

The parents of the three naturally occurring radioactive decay series (text-fig. 1),232Th, 238U and 235U, have existed since the time of formation of the earth and through the process of radioactive decay have continuously generated their shorterlived daughter radio-isotopes. Under conditions where these decay products are not separated from the parents the situation referred to as secular equilibrium may be attained at which the activity ratio of any two daughters in the same decay chain is unity. The time required for the attainment of this situation corresponds to several half-lives of the longest lived daughter nuclide. In a great many instances, however, secular equilibrium is not achieved. Excellent examples of disequilibrium are to be found in the distribution of natural radioactive decay series elements in the oceans and sediments. These situations can be used to advantage in marine geochemistry to obtain information on residence times of elements in the oceans and rates of sedimentation occurring under a variety of conditions.

The radioactive decay series 138Nd → 138Pr → 138Ce

1970 ◽  
Vol 48 (14) ◽  
pp. 2151-2157 ◽  
Author(s):  
James J. Hogan
Keyword(s):  
Direct Measurement ◽  
Gamma Rays ◽  
Radioactive Decay ◽  
Excited Level ◽  
Branching Ratio ◽  
Decay Chain ◽  
Decay Series

Measurements of the energies and intensities of gamma rays associated with decay of 138Nd, 138Prm, and 138Prg have been performed using a Ge(Li) detector. The branching ratio to a previously unreported excited level of 138Pr (328.1 keV) has been measured, thus allowing for direct measurement of the decay of 138Nd. Half-lives of 2.20 ± 0.07 and 5.04 ± 0.09 h have been measured for 138Prm and 138Nd, respectively. Decay schemes for 138Prm → 138Ce and for the decay chain 138Nd → 138Prg → 138Ce are proposed.

scholarly journals Computational Design of Sensitized Combustion Chemistry Experiments

2021 ◽  
Vol 7 ◽  
Author(s):  
Cody Ising ◽  
Pedro Rodriguez ◽  
Daniel Lopez ◽  
Jeffrey Santner
Keyword(s):  
Shock Tube ◽  
Initial Conditions ◽  
Computational Design ◽  
Reaction Rates ◽  
Oxidation Reactions ◽  
Combustion Chemistry ◽  
Experimental Conditions ◽  
As Species ◽  
User Friendly

In combustion chemistry experiments, reaction rates are often extracted from complex experiments using detailed models. To aid in this process, experiments are performed such that measurable quantities, such as species concentrations, flame speed, and ignition delay, are sensitive to reaction rates of interest. In this work, a systematic method for determining such sensitized experimental conditions is demonstrated. An open-source python script was created using the Cantera module to simulate thousands of 0D and hundreds of 1D combustion chemistry experiments in parallel across a broad, user-defined range of mixture conditions. The results of the simulation are post-processed to normalize and compare sensitivity values among reactions and across initial conditions for time-varying and steady-state simulations, in order to determine the “most useful” experimental conditions. This software can be utilized by researchers as a fast, user-friendly screening tool to determine the thermodynamic and mixture parameters for an experimental campaign. We demonstrate this software through two case studies comparing results of the 0D script against a shock tube experiment and results of the 1D script against a spherical flame experiment. In the shock tube case study we present mixture conditions compared to those used in the literature to study H + O2 (+M)→HO2(+M). In the flame case study, we present mixture conditions compared to those in the literature to study formyl radical (HCO) decomposition and oxidation reactions. The systematically determined experimental conditions identified in the present work are similar to the conditions chosen in the literature.

Radioactive ingrowth in a natural decay series. A demonstration

1990 ◽  
Vol 67 (5) ◽  
pp. 374
Author(s):  
K. Murray Matthews ◽  
Rachael M. Larkin
Keyword(s):  
Decay Series ◽  
Natural Decay

DECSERVIS-2: A tool for natural decay series mass flow simulation

2009 ◽  
Vol 67 (11) ◽  
pp. 1992-1997 ◽  
Author(s):  
Saad Azzam ◽  
Juhani Suksi ◽  
Michael Ammann
Keyword(s):  
Mass Flow ◽  
Flow Simulation ◽  
Decay Series ◽  
Natural Decay

Simultaneous resolution of reactive radioactive decay, non-isothermal flow, and migration with application to the performance assessment for HLW repositories

2010 ◽  
Vol 98 (6) ◽  
Author(s):  
R. Juncosa ◽  
I. Font ◽  
J. Delgado
Keyword(s):  
Ion Exchange ◽  
Radioactive Decay ◽  
Chemical Species ◽  
High Level Waste ◽  
Chemical Components ◽  
Clay Material ◽  
Decay Series ◽  
And Migration ◽  
High Level ◽  
Radioactive Species

AbstractRadioactive decay is an important subject to take into account when studying the thermo-hydro-dynamic behavior of the buffer clay material used in the containment of radioactive waste. The modern concepts for the multibarrier design of a repository of high level waste in deep geologic formations consider that once canisters have failed, the buffer clay material must ensure the retention and/or delay of radionuclides within the time framework given in the assessment studies. Within the clay buffer, different chemical species are retarded/fixed according to several physicochemical processes (ion exchange, surface complexation, precipitation, matrix diffusion, ...) but typical approaches do not consider the eventuality that radioactive species change their chemical nature (The radioactive decay of an element takes place independently of the phase (aqueous, solid or gaseous) to which it belongs. This means that, in terms of radionuclide fixation, some geochemical processes will be effective scavengers (for instance mineral precipitation of crystal growth) while others will not (for instance ion exchange and/or sorption).In this contribution we present a reactive radioactive decay model of any number of chemical components including those that belong to decay series. The model, which is named FLOW-DECAY, also takes into account flow and isotopic migration and it has been applied considering a hypothetical model scenario provided by the project ENRESA 2000 and direct comparison with the results generated by the probabilistic code GoldSim. Results indicate that FLOW-DECAY may simulate the decay processes in a similar way that GoldSim, being the differences related to factors associated to code architecture.

Chromatographic generator systems for the actinides and natural decay series elements

2011 ◽  
Vol 99 (3) ◽  
pp. 151-159 ◽  
Author(s):  
Daniel R. McAlister ◽  
E. Philip Horwitz
Keyword(s):  
Decay Series ◽  
Natural Decay

An Analogue Validation Study of Natural Radionuclide Migration in Crystalline Rocks using Uranium-Series Disequilibrium Studies

1985 ◽  
Vol 50 ◽  
Author(s):  
J. A. T. Smellie ◽  
A. B. MacKenzie ◽  
R. D. Scott
Keyword(s):  
Natural Radionuclide ◽  
Hydrothermal Activity ◽  
Crystalline Rock ◽  
Crystalline Rocks ◽  
Radionuclide Migration ◽  
Uranium Series ◽  
Saturated Rock ◽  
Decay Series ◽  
Uranium Migration ◽  
Natural Decay

AbstractConcentrations and isotope ratios of natural decay series radionuclides have been studied in three contrasting crystalline rock drillcore sections intersecting water-conducting fractures deep in the bedrock. Radioactive disequilibria resulting from rock-water interactions were observed in two of the cores. These indicated uranium migration along distances of 40 cm or more on a timescale of 106 years in conjunction with thorium immobility under the same conditions. Fracture surface minerals showed a high affinity for radionuclide retardation and a limit of about 3 cm is suggested for the migration of radionuclides from fracture fluids into the saturated rock. This limit may correspond to enhanced matrix porosities resulting from earlier hydrothermal activity along the same channels.

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