The postulate that the average number of lattice displacements is directly proportional to the available energy is carried one step further; it is assumed that damage to steel (particularly in regard to brittle fracture) is proportional to the number of lattice vacancies that occur. The model, although crude, permits estimation of the relative damage resulting from differences in neutron spectra. The results can be used as a rough method of correcting damage data for the effect of the neutron-energy spectrum. Radiation damage calculations for steel, relative to those for a fission spectrum, were made for neutron spectra that result from fission neutrons penetrating water or graphite. The results were plotted as a function of effective distance from the fission source. From this plot it is possible to make a conservative estimate of the correction factor to apply to damage data obtained with different neutron spectra. (auth)

Effective energy cutoffs have been calculated on an IBM7090 computer for Cd, Gd, Sm, and B filters as functions of filter geometry, the ratio of Maxwellian to epithermal flux (assumed to be 1/E), the lower energy limit of the 1/E flux, the energy corresponding to the Maxwellian most probable (modal) velocity and filter thickness. The geometrical configurations were spherical (which on the assumptions madc is equivalent to a beam flux case), cylindrical and slab. By the use of two or three different filters (Cd and Gd and perhaps Sm) it should be possible to detect resonances in the thermal to cutoff energy regions, in addition to measuring resonance integrals and thermial cross sections of unknown nuclides. (auth)

The temperature coefficient of the Reactivity Measurement Facility was found to be 49 plus or minus 1 mu k/ deg C (1 mu k = 10/sup -6/ DELTA k/k) in the range 15.4 to l7.8 deg C. The change in the net reactivity of a standard sample was --0.48 plus or minus 0.02, --0.66 plus or minus 0.03, and --0.78 plus or minus 0.02 mu k/ deg C in three measuring positions. These low values generally make temperature corrections insignificant. The above results are compared with previous determined values. This information developed in the RMF should be generally applicable to flux-trap-type reactors such as the Advanced Reactivity Measurement Facility (ARMF) and ARMF-ll, now under construction. RMF was dismantled in April 1962. (auth)

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Will Wilson, regarding a legal question submitted for clarification: Whether line item 20, to the Building Commission, in the General Appropriation bill is available to be used in refinishing certain furniture for the Third Court of Civil Appeals.

In May, 1961, it waa determined no renewed nuclear reaction in the SL-1 pressure vessel was possible as long as water was excluded. It was therefore possible to proceed with the final phase of the SL-1 recovery. This work consisted of moving the pressure vessel and core to the Hot Shop at the north end of the National Reactor Testing Station, dissecting and analyzing the reactor and its components, cutting up and burying the reactor building, and decontaminating the rest of the SL-1 area. These things were accomplished by the General Electric Company between May 1961 and July 1962. It was determined that the central control rod was bound in its shroud at a position corresponding to 20- inch withdrawal. Analysis of the pertinent data showed that the amount of reactivity associated with this rod position, inserted at a rate compatihie with manual withdrawal of the rod, can explain the significant evidence which was coliected. No other means of withdrawing the rod was found to be in accordance with the evidence. It was found that the relatively low yield (130 Mw-sec) nuclear excursion produced a water hammer with pressures up to 10,000 psi, which, in turn, caused the pressure vessel …

The diffusion rate of O in anion-deficient zirconia, ZrO/sub 1.994/, was determined by the interface migration of stoichiometric oxide and is represented by the equation D = 0.055 exp (--33,400 surface proces 3100/RT). A comparison was made with other processes that occur in the metal and the oxide. Excellent agreement was noted between activation energies of O diffusion in ZrO/sub 1.944/ and those for parabolic or cubic oxidation in both air and water. It appears that O diffusion in the oxide is rate-controlling during oxidation of the metal. The corrosion and oxidation behavior of Zr and some alloys are discussed in terms of the oxide defect structure and the electric conductivity behavior in the oxide. A speculative mechanism for corrosion transition to linear rates was suggested on the basis of preferential oxidation of a grain boundary metallic phase. The nature of the phase and of its formation and elimination are discussed. (auth)

Technical report. From Abstract : "Thermal, metallographic, and vapor pressure data were obtained to establish the phase boundaries and the standard free energy, enthalpy, and entropy of formation for the compounds in the yttrium-zinc system."

From abstract: "Distillation procedures used for purifying yttrium metal, producing metal containing less than 150 ppm oxygen and lower concentrations of most of the other common impurities, are discussed. Some of the physical and mechanical properties of the distilled yttrium indicate: (1) a melting point of 1510°C, (2) a solid state transformation at 1459°C obtained from high temperature resistivity data, (3) a Rockwell H hardness of 60 and (4) improved rolling and swagging characteristics."