Fission dynamics

Peroxisome proliferator-activated receptor (PPAR) y and PPARra agonists modulate mitochondrial fusion-fission dynamics Relevance to reactive oxygen species (ROS)-related neurodegenerative disorders PLoS One 8 e64019. doi 10.1371/journal.pone. 0064019... 

Electronic Shell Effects in Fission Barriers and Fission Dynamics of Metal Clusters... 

Zagrebaev, V.I., Itkis, M.G., Oganessian, Yu.Ts. Fusion-fission dynamics and perspectives of future experiments. Phys. At. Nuclei 66, 1033-1041 (2003)... 

Zagrebaev, V.I. New approach to description of fusion-fission dynamics in super-heavy element formation. J. Nucl. Radiochem. Sci. 3, 13-16 (2002)... 

Zagrebaev, V.I. Fusion-fission dynamics of super-heavy element formation and decay. Nucl. Phys. A734, 164-167 (2004)... 

Yamamoto, S. and Hyodo, S. (2003) Budding and fission dynamics of two-component vesicles. Journal of Chemical Physics, 118, 7937-44. 

Adams, R.E., W.E. Browning, Jr., and R.D. Ackley, Containment of Radioactive Fission Gases by Dynamic Adsorption, Industrial and Engineering Chemistry, 51 1467-1470 (1959). 

Wu SP, Wu G, Surerus KK, Cowan JA (2002) Iron-sulfur cluster biosynthesis. Kinetic analysis of [2Fe-2S] cluster transfer from holo ISU to apo Fd role of redox chemistry and a conserved aspartate. Biochemistry 41 8876-8885 Yaffe MP, Stuurman N, Vale RD (2003) Mitochondrial positioning in fission yeast is driven by association with dynamic microtubules and mitotic spindle poles. Proc Natl Acad Sci USA 100 11424-11428... 

This paper deals mainly with the condensation of trace concentrations of radioactive vapor onto spherical particles of a substrate. For this situation the relation between the engineering approach, the molecular approach, and the fluid-dynamic approach are illustrated for several different cases of rate limitation. From these considerations criteria are derived for the use of basic physical and chemical parameters to predict the rate-controlling step or steps. Finally, the effect of changing temperature is considered and the groundwork is thereby laid for a kinetic approach to predicting fallout formation. The relation of these approaches to the escape of fission products from reactor fuel and to the deposition of radon and thoron daughters on dust particles in a uranium mine is indicated. 

If we apply these equations to the condensation of a fission product in a cooling nuclear fireball, we must deal with sources from radioactive growth, sinks from radioactive decay, and dynamic conditions of temperature drop. In the simple case of radioactive decay... 

This chapter has outlined the basic ingredients of a scheme for predicting from fundamental quantities the rate of uptake of fission products by spherical particles under dynamic conditions of temperature and pressure. A subsequent paper by Adams, Quan, and Balkwell (1) will present laboratory verification that the approach is on sound ground for isothermal conditions. Additional work is desirable to test the validity of the anisothermal approach to various cooling rates over large temperature extremes. 

Polyelectrolyte complex membranes are phase-inversion membranes where polymeric anions and cations react during the gelation. Inorganic ultrafiltration membranes are formed by depositing particles on a porous substrate. Dynamic membranes are concentration polarization layers formed in situ from the ultrafiltration of colloidal material analogous to a precoat in conventional filter operations. Track-etched membranes are made by exposing thin films (mica, polycarbonate, etc.) to fission fragments from a radiation source. 

Biofilms can develop relatively unhindered by the external environment. This is because bacteria reproduce by binary fission daughter cells using breakdown products of dead bacterial cells as a nutrient source), in addition to the protective and dynamic nature of the matrix. 

Brunner, D., and Nurse, P. (2000). CLIP170-like Tiplp spatially organizes microtubular dynamics in fission yeast. Cell 102, 695-704. 

Reisler, H. and Wittig, C. (1992). State-resolved simple bond-fission reactions Experiment and theory, in Advances in Chemical Kinetics and Dynamics, ed. J.A. Barker (JAI Press, Greenwich). 

Photodissociation of small polyatomic molecules is an ideal field for investigating molecular dynamics at a high level of precision. The last decade has seen an explosion of many new experimental methods which permit the study of bond fission on the basis of single quantum states. Experiments with three lasers — one to prepare the parent molecule in a particular vibrational-rotational state in the electronic ground state, one to excite the molecule into the continuum, and finally a third laser to probe the products — are quite usual today. State-specific chemistry finally has become reality. The understanding of such highly resolved measurements demands theoretical descriptions which go far beyond simple models. 

Rice et al. [99] developed a global potential energy surface based on the Mowrey et al. [103] results and performed extensive classical trajectory calculations to study the dynamics of the CH2NN02 dissociation reactions. They calculated rates for reactions (III) and (IV) with classical barriers of 35 and 37 kcal/mol, respectively. They found that N-N bond fission dominates at low energy but that HONO elimination is competitive. Chakraborty and Lin [104] predict the opposite on the basis of their ab initio barriers and RRKM theory calculations. The two dissociations channels are closely competitive and it is not clear that ab initio methods are sufficiently reliable to distinguish between two reactions that have such similar energy requirements. Also, the Zhao et al. results [33] are not in accord with the theoretical predictions. 

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