The present report is concerned with the electronic relay which, upon the reaching of a pre-determined value of ionization current in the associated chamber, actuates the safety rod release mechanism. The are here proposed two independent suggestions: (1) An improved trip circuit of such sensitivity and stability as to allow it to be actuated by a signal directly from the chamber without the necessity of interposing intermediate amplifier stages. The value of chamber current at which tripping occurs is stable to +- 0.4%. (2) A triple-wound relay to prevent shut-downs of the pile which would otherwise be caused by development of defects in the safety circuits.

From abstract: "The Safety Program of the University of California Radiation Laboratory at Livermore, California, is discussed in terms of the functions of the six independent safety groups that comprise the laboratory's primary safety organization, namely, Industrial Safety, Medical Safety, Fire Prevention and First Aid, Health Chemistry, Health Physics, and High-Explosive Safety Groups."

The following document describes observations from tests on neptunium metal and their reactions to different room temperatures.

"The following is an evaluation of a modified Zircaloy-2 ingot melted at WAPD using the non-consumable electrode melting technique. The nominal composition of the alloy is 0.5% tin, 0.1% iron, 0.1% chromium, and 0.5% nickel."

Report discussing a study testing features of the absorption spectra of different oxidation states of neptunium and perchloric acid concentration's effects on the spectra. Data regarding a disproportionation reaction present in neptunium(V) solutions in concentrated acid is included.

Report discussing measurements of thermal conductivity and heat capacity for uranium-chromium and uranium-iron eutectic alloys at room temperature. The resulting values were intended for use in design calculations until more accurate data at other temperatures was obtained.

The following report analyzes experiments on urinary samples of personnel who were exposed to radioactive materials. This report describes the procedure employed for this assay, and data to show its performance and reasons for its present course are presented.

Radioactive decay data are used to calculate the atomic masses of the heavy isotopes, A> 203. The four radioactive families are then connected by means of neutron binding energies known from reactions on various isotopes. Finally all the masses are collectively adjusted for the best fit with mass spectrographic information available in this region. The masses so calculated are presented. Differences between masses of isotopes are estimated to have an of (plus/minus) 0.00020 mas units or about 200 Kev; the position of the masses taken collectively is in doubt by about 1.5 Mev.

The thermal decomposition of the higher oxides of praseodymium and americium have been investigated.

Calculations were made to determine the temperature at various points of a thick disc and cap, on the assumptions that the heat production rate is uniform throughout the slug and that the slug is in perfect thermal contact with the cap. Results obtained by different methods of computation are compared with each other and with results obtained by Drew on the Paschkis electrical network computer at Columbia University.

In support of an in-reactor thermocouple stability testing program now in progress, laboratory studies were made relative to the stability of thermocouple bundles similar to those projected for in-reactor use. Two sets of chromel-alumel, copper-constantan and iron-constantan thermocouples were held for extended periods at 300 C in successive atmospheres of 75% helium-25% carbon dioxide. 100% carbon dioxide and air. Thermocouple stability was verified by measuring emf's at the freezing point of lead. The results of these tests are to be used to evaluate data obtained from like thermocouples subjected to condition similar to the laboratory tests with the added facet of reactor irradiation.

Corrosion rates of present reactor grade uranium were measured in boiling distilled water and were found to have higher values almost by a factor of two then previously reported corrosion rates of uranium. Mallinckrodt biscuit metal showed corrosion rates in the same medium somewhat lower than reactor grade uranium, and high purity metal prepared at Argonne National Laboratory corroded considerably less rapidly than the biscuit metal.