Abstract
We have observed very rapid spontaneous heating of the cold solid methane moderator when irradiated by fast neutrons at low temperatures in the Intense Pulsed Neutron Source. In one instance enough heat was released to vaporize a fraction of the methane. We have also induced smaller rapid heat releases —both by slowly warming irradiated methane and by diminishing the effectiveness of cooling. An explanation for these observations is that energy stored in the form of reactive species (H, CH3,...) accumulates in solid methane irradiated at low temperatures, and is released by thermally activated diffusion and subsequent reaction. During irradiation, the density of reactive species can build up sufficiently to become unstable as the rate of heat release due to recombination exceeds the rate of heat loss to the cooled surroundings. Similar effects may occur in other cryogenic moderator materials, and may be responsible for the jets observed from cometary nuclei.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
1. Carpenter, J. M. et al. in Proc. int. Collaboration on adv. Neutron Sources VIII (Rutherford Appieton Lab. RAL-85-110, 1985) Vol. 1, 311-318 (1985). 2. Carpenter, J. M., Walter, U. & Mildner, D. F. R. in Proc. int. Collaboration on adv. Neutron Sources IX (Schweizerisches Institut fur Nuklearforschung ISBN 3-907998-01-04) 279-303 (1987). 3. Cottrell, A. H., Bell, J. C., Greenough, G. B., Lomer, W. M. & Simmons, J. H. W. in Proc. 2nd UN int. Conf. on the Peaceful Uses of Atomic Energy Vol. 7, 315-327 (United Nations, New York, 1958). 4. Mitchell, E. W. J. & Taylor, M. R. Nature 208, 638-641 (1965). 5. Khitrin, L. N. The Physics of Combustion and Explosion (National Science Foundation, Washington, 1962). 6. Bowden, F. P. & Yoffe, A. D. Fast Reactions in Solids (Butterworths, London, 1958). 7. Kerr, R. A. Science 232, 320-323 (1986). 8. Brown, W. L., Foti, G., Lanzerotti, L. J., Bower, J. E. & Johnson, R. E. NucL Instr. Meth. B19/20, 899-902 (1987). 9. Reimann, C. T. et al. Surf. Sci. 147, 227-240 (1984). 10. Ikeda, S., Waranabe, N., Satoh, S., Furusaka, M. & Inoue, K. KENS Report VI, Jap. Lab. for High Energy Phys. Rep. 86-2 (1987). 11. Brown, D. W., Florin, R. E. & Wall, L. A. J. phys. Chem. 66, 2602-2612 (1962).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Carpenter, J. Thermally activated release of stored chemical energy in cryogenic media. Nature 330, 358–360 (1987). https://doi.org/10.1038/330358a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/330358a0
This article is cited by
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.
