Abstract:"The creep resistance of various uranium binary alloys was investigated at 1500 and 1800 F in vacuum. Tests were made on alloys of uranium with beryllium, columbium, molybdenum, tantalum, titanium, and zirconium and on molybdenum-UO2 composites. Of the alloys examined, those of the uranium-molybdenum system exhibited the best creep resistance. At 1500 F, creep rates of about 0.005%/hr were produced in uranium-molybdenum alloys by a stress of 2500 psi and, at 1800 F, similar creep rates were obtained in composites of 90 wt % molybdenum-10 wt % UO2 by a stress of 12,000 psi."

Abstract: "This report describes the results of X-ray diffraction examination of reaction products from a series of experiments performed by Mallinckrodt Chemical Works as an acid in understanding the process of bomb reduction of UF4. UF4 is initially reduced to UF3 by magnesium at 560 C., and subsequently to metal at 600 C. MgF2 from the initial reaction forms a coating on the magnesium which retards the final spontaneous reaction."

Abstract: "The spectrum of plutonium has been observed over the temperature range of 2000 to 2600 C and a wavelength coverage of 3476 to 6888 A. The spectrum was excited in a modified King furnace."

Abstract: "Extraction equipment of the multistage mixer-settler type has been found useful for providing the intensive contact between phases that is required in processes involving complex compounds of the heavy metals. In this report, the factors of mixer-settler design and operation are discussed with reference to the known types of mixer-settler units. Following this review, a detailed description is given of mixer-settler units constructed and installed in this laboratory."

The following report analyzes whether there is a difference between the neutron streaming in the "armor plate" and 347 stainless steel.

The following report analyzes several reported incidents of uranium-rich zirconium-uranium explosions. This report offers notes designed to describe conditions sufficient to cause an explosion with an 80% wt. uranium alloy.

Due to some lack of knowledge of the energy per fission, there has been some uncertainty over the absolute power of the Bulk Shielding Reactor. This report analyzes measurements to state the absolute power of the BSR within a few percent.

"These notes are intended to serve as a summary of the current knowledge of properties of materials. In the future some need may exist for related information on methods od testing, design and fabrication. This issue presents information on thorium with subdivisions..."

The angular distribution of fission fragments from the neutron-induced fission of several isotopes has been studied. Distributions were observed for thermal neutrons on U233 and U235, Lady Godiva leakage neutrons on U235 and U238, and 14 Mev neutrons on U233, U235, U238, Th232, and Np237. No anisotropy was observed for thermal neutron fission, whereas for Lady Godiva neutrons and 14 Mev neutrons the probability of fission along the axis of the neutron beam was determined to be higher than for fission in the orthogonal direction. Experimental results are given on pages 10 and ll.

Semi-empirical modifications of age theory have been made to interpret the critical masses of proton moderated assemblies, which may or may not have reflectors of various substances, in particular, water or steel. Section I shows that critical masses of untamped water moderated systems can be calculated by use of an appropriate age and linear extrapolation length. Assuming that all captures and fissions take place at thermal, a familiar expression can be set up which contains the age and extrapolation length which are not well determined by theory. An age value suggested by theory, (Sec. II) is taken and ORNL criticality data (K343) are used to find the best extrapolation length. With these values the K343 critical mases can be computed to bout +-5%, which is their estimated experimental uncertainty; this for H/U-235 atomic ratios between 43 and 755. Section II contains a theoretical discussion of effects which the simple "theory" of Sec I neglects. It is indicated that several of these effects compensate to make a simple theory more useful than one would believe at first sight. to take into account reflectors of water, water shield by cadmium, or steel of various thicknesses, it proves sufficient to alter the extrapolation …

Plus-minus ratios for pion production by 340-Mev proton bombardment were measured at 13 Mev, 18 Mev, and 42 Mev with the use of the spiral orbit spectrometer.

Progress on projects on experimental physics, theoretical physics, MTA Target-Physics Program, accelerator construction and operation, chemistry, biology and medicine, plant and equipment.

It is proposed to test gaps corresponding to deuteron energies in the range of 0.45 to 4.5 Mev. The accelerator to be modeled is a 48 mc/sec cylindrical cavity in the TM010 mode with [formula] repeat length, [formula] gap, 0.25 megavolt per cavity foot peak r.f. gradient and strong focusing magnets alternating polarity at each drift tube.

Engineering notes on limiting bore diameter, angular divergence in a linear accelerator.

This technical report is a summary of unclassified theoretical work on propagation of one-dimensional shock waves and on the propagation of spherical shock waves in gases.