Negative burning rate modifier

Burning rate catalyst Burning rate negative catalyst Negative burning rate modifier Metal fuel... 

A fuel composition can be eliminated or modified if any of the performance characteristics are deficient. For example, the plutonium mass loading should meet a minimum quantity per rod to burn for the desired cycle length at a specified average pin power. In addition, the net temperature coefficient must be negative and burnable poisons should bum at rates comparable to the plutonium. 

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