Weapons-grade material

The amount of HEU that becomes avadable for civdian use through the 1990s and into the twenty-first century depends on the number of warheads removed from nuclear arsenals and the amount of HEU in the weapons complex that is already outside of the warheads, ie, materials stockpdes and spent naval reactor fuels. An illustrative example of the potential amounts of weapons-grade materials released from dismanded nuclear weapons is presented in Table 7 (36). Using the data in Table 7, a reduction in the number of warheads in nuclear arsenals of the United States and Russia to 5000 warheads for each country results in a surplus of 1140 t of HEU. This inventory of HEU is equivalent to 205,200 t of natural uranium metal, or approximately 3.5 times the 1993 annual demand for natural uranium equivalent. 

Mixture of the ortho, meta, and para isomers. Colorless to light yellow, slightly viscous liquid with a pungent and aromatic odor, resembling lilacs or elder blossoms. Weapons grade material is a black liquid. 

Colorless odorless crystals. Weapons grade material is a dark brown, thick, viscous, semisolid resembling shoe polish. It has in the past been used industrially as a wood preservative, pesticide, and herbicide for cacti. 

Bright canary-yellow crystals that are odorless but produce irritation. Weapons grade material is a dark green to brown solid. When dispersed as a particulate cloud from a thermal munition, it has a characteristic "smoky" odor. 

The design of a production facility provides important information regarding whether the facility is intended to produce pharmaceutical grade products or biological weapon grade materials. Relevant design elements include containment, purification equipment, sterilization equipment, and ventilation and filtration systems. 

Described herein are the results of criticality calculations for single-, four-, six-, and seven-cell gas core models. These beryllium-reflected and -moderated UFs systems all have potential merit relative to both the proliferation of weapons-grade materials and the con-servative/efflcient utilization of thorium and uranium resources. A brief investigation of the consequences of denaturing the with indicates neutronic feasibility for ratios up to 20 1 however, the practical-... 

Some DU is drawn from these stockpiles to dilute high-eruiched (approximately 90%) uranium released from weapons programs, particularly in Russia, and destined for use in civil reactors. This weapons-grade material is diluted to about 25 1 with depleted uranium, or 29 1 with depleted uranium that has been enriched slightly (to 1.5% U-235) to minimize levels of (natural) U-234 in the product. 

The Package-Reactor is an LWR with moderation ratio similar to conventional LWRs, so the properties of the fresh and spent fuel are also very similar. Therefore, the proliferation resistance features are also similar to those of conventional LWRs, that is, the enrichment of fresh fuel by is less than 5% (by weight) and it is difficult to convert it to a weapon-grade material. 

The same technical features prevent or discourage an undeclared production of weapon grade material in the CHTR. Here, the reactor operation with low excess reactivity is also of certain value. 

The activities undertaken so far have served to indicate the great flexibility of fast reactors, which can be used either to consume plutonium or to generate it, and can utilise plutonium with a wide range of isotopic composition, from weapons-grade material which is high in Pu-239 to plutonium which has been recycled several times in thermal or fast reactors and contains more than 50% of the non-fissile isotopes Pu-240 and Pu-242. During the next decade further work to optimise the performance of burner reactors can be expected. Some of the outstanding questions are as follows. 

The technical features that prevent or discourage the production of weapon grade material in AHWR are ... 

To manufacture weapons-grade material in sufficient quantities for an efficient (read, high explosive) yield is a major industrial operation. It requires the level of technical attainment and the resources of a nation-state. In the face of modem satellite observational technologies, it is not so easy to hide the fabrication plants, though underground siting is obviously preferred and is known to occur. 

The same premise applied to safeguarding the material. "It is more valuable than gold," Price noted at a later meeting with the commissioners. "Banks know how to protect gold. We think these companies know how to protect this material." From a different perspective, Strauss challenged Price s argument. The value of the material did not bother Strauss, but possible diversion to a potential enemy did. "To the extent that weapons grade material or spiked material is involved, covert op-... 

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