标题: 《Periodic Table Californium 》作者：- Michael Swanwick【EPUB】 [打印本页] 作者: zaq 时间: 2013-8-18 08:36 标题: 《Periodic Table Californium 》作者：- Michael Swanwick【EPUB】 Michael Swanwicks Periodic Table of Science Fiction 98 Cf Californium251 Nuclear Handguns With its prodigious spontaneous fission rate Cf-252 serves well as a compact intensefission-spectrum neutron source and is thus the only isotope of californium of any significantindustrial importance. Militarily however its Cf-251 that really kicks butt. Heres why: As a rule isotopes with even-numbered masses have high spontaneous fission ratesand are less fissile. Those with odd numbers are highly fissile and have lower spontaneousfission rates. So the even isotopes are good for radiation sources the odd ones forexplosives. Cf-251 is extremely fissile with a comparatively low spontaneous fission rate andan 800-year half-life. A critical mass of 1.7 kg can easily be made into a .45-caliberprojectile. The worlds only nuclear sidearm is the Screaming Eagle