Abstract: This technical report contains a summary of analytical and experimental work performed on SM-1 Core II, with special components is presented. The effects of these special assemblies upon power distribution and core reactivity were calculated and compared to experimental measurements. A thermal analysis was conducted to determine steady state and transient performance of the special test components of the core as well as some of the hotter standard Core II components. Experimental work discussed includes individual reactivity effects of all the special elements and the total effect of all of the elements. Power mappings were also made and are reported.

From introduction: "Development of nuclear reactor cores having high power density, long fuel life, and low fabrication costs is the objective of this program sponsored by the AEC."

From introduction: "This report presents a conceptual design study of the once-through superheat reactor design based on experimental heat transfer results obtained during the fall of 1960 on Task F-2 of the AEC sponsored Nuclear Superheat Project."

From Introduction: "The present semiannual progress report introduces more active consideration than has been given in the past (by us, at least) to the importance of energy degradation in DCX-like devices. The following pages introduce also a new major apparatus designated as DCX-2. Some of these concepts cannot as yet be released publicly and therefore Chap. 3 of this report, covering the DCX-EP-B design, is being issued separately, with restricted distribution, as ORNL-3044."