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Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
P. K. Job, K. Subba Rao, M. Srinivasan
Nuclear Science and Engineering | Volume 84 | Number 3 | July 1983 | Pages 293-298
Technical Note | doi.org/10.13182/NSE83-A17798
Articles are hosted by Taylor and Francis Online.
It was shown earlier that nonsolvated crystalline BeH2 could serve as an effective moderator in reducing nuclear critical masses below minima achievable in CH2-moderated systems on account of its (n, 2n) reactivity bonus and higher hydrogen number density. The 9Be cross sections used in these calculations were found to overestimate the (n, 2n) multiplication. The precise (n, 2n) contribution to system reactivity and critical mass in the light of the latest 9Be cross-section data are evaluated. The results show that in the case of BeH2-moderated and BeO-reflected systems, five additional neutrons are born in the reaction multiplication in beryllium per 100 fission neutrons released in the core, resulting in a reactivity gain of ∼4%. The corresponding reduction in critical mass is ∼16%. The critical masses calculated with corrected 9Be cross sections show that the crystalline BeH2-moderated and BeO-reflected systems apparently have the smallest possible theoretical critical masses, namely, 0.180, 0.137, and 0.105 kg for 235U, 233U, and 239Pu, respectively.