Abstract. A series of paired explosions in a salt mine near Winnfield, Louisiana, has been conducted to test a theory by Dr. A. L. Latter concerning seismic decoupling by underground cavities. The theory predicted a decoupling of about 100. Free-field and surface measurements from an explosion in either a 6-ft- or a 15-ft-radius spherical cavity were compared with similar measurements from a completely tamped explosion. Shot sixes were from a 10 lb up to a few tons. Surface measurements were made out to 100 km and covered the frequency range from 0.05 to 100 cpa. The experiment confirmed that decoupling does occur. The actual decoupling factor as a function of frequency is presented and compared with the Latter theory.

The power of nuclear track research emulsion as a fast neutron dosimeter is examined in the exposure of a human phantom to PuBe neutrons. Semiautomatic track scanning and high-speed data analysis obviate the major disadvantages of this dosimeter, and allow the following basic information to be obtained without a serious cost in time: the rulative proton recoil energy spectrum, the absolute differential proton track den sity spectrum, and the average proton recoil energy at various locations in the phantom. From this are calculated the total absorbed local tissue doze due is proton recoils, the local thermal neutron intensity, and that portion of the tissue doze due to thermal [formula] tracks.

A set of 69 pile yield curves for the production of plutonium, americium, and curium isotopes in a neutron flux of 5 x 10<sup>14 cm<sup>-2 sec<sup>-1 is given. The differential analyzer of the University of California Radiation Laboratory was used in obtaining the curves. The curves are given also on log-log plots for comparison.

Calculations of the photonuclear giant resonance according to the Wilkinson model are presented in this report. In this model the giant resonance in the cross section for absorption of gamma rays by nuclei is ascribed to the excitation of large numbers of nucleons in closed shells. The model generally predicts correctly the integrated cross section for the giant resonance, bu the resonance energy is too low. Results are presented in a series of tables and formulas so that the integrated cross section may be calculated for any given nucleus.

From introduction: "The work described in this report was undertaken as part of an experimental study to determine the effectiveness of radiofrequency field in heating the ions of a hydrogen or deuterium plasma. The ultimate aim is to find a method of heating a deuterium plasma until an appreciable rate of nuclear reaction takes place."

Abstract: "A magnetohydrodynamic model of a plasma-magnetic field instability, using liquid sodium, has been observed. The growth rate and wave length of the Taylor-type acceleration instability was observed to be in agreement with the theory of Kruskal and Schwarzschild."

Abstract: "A magnetohydrodynamic model of plasma-magnetic field instabilities, using liquid sodium, has been observed. The growth of flutes in the mirror geometry was observed for the case of [beta] = NKT/H²/8w = 1."

The following report discusses a survey of seventy-seven interactions of K- mesons in flight in nuclear emulsion with seven decays in flight, and finding four inelastic scatterings.

From abstract: This bibliography consists of references pertaining to "Effects of Nuclear Radiation Upon Electronic and Electrical Components", and to "Electronic and Electrical Components for Critical Environments". References were compiled from the Classified and Unclassified report literature and the published literature. The following indexes and abstract journals were used: Weapons Data Index, AEC Card Catalog, Engineering Index (1950-55), and Office of Technical Services, Research Reports (1956-March '57).

Two IBM-704 codes have been written which are auxiliary to the Bevatron orbit code BOC. The first, BEFCYF, interpolates among tabulated values of the median-plane magnetic flux density of the Bevatron to produce an equivalent array of values in a form appropriate to BOC. The second, DBDT, produces azimuthal derivatives of the fields produced by BEFCYF. The internal operation of BEFCYF and DBDT is described, and instructions for their execution are given.

The coefficients of thermal conductivity of aluminum-bismuth metal-to-metal bonds, and of aluminum and bismuth surfaces in contact under pressure, were measured.

Introduction: This note describes briefly the current concept of the experimental program on source development for mirror machines. There are two major facilities involved: (1) A comparatively small machine whose code name is "Guppy", and, (2) A larger d.c. mirror geometry whose code name is "Waldo."

Pulse-amplitude discriminators are useful in nuclear counting to separate signals of greater amplitude from a background of unwanted or noise signals of lesser amplitude. As used here, the term "fast" implies circuits capable of responding to pulses between a nanosecond and a microsecond in duration. An ideal discriminator would produce for any incoming signal whose amplitude is greater than a threshold bias level, an output pulse of constant amplitude, duration, and delay with respect to the input signal, regardless of the incoming duration and rate; and for signals less than the threshold, zero output.

The following report describes the workings and development of the nuclear ramjet propulsion systems.

Report discussing theories of irreversible thermodynamic processes. "The purpose of this review is to collect the presently available experimental data for a variety of quite different irreversible phenomena and to show that this evidence does indeed verify the Onsager Reciprocal Relations."

Abstract: "The free energy (surface tension) of a liquid film can withstand atmospheric pressure across a maximum theoretical gap of 10-(-3) cm between solids if the liquid wets and bridges the sides of the gap continuously. The eutectic alloy of Ga, lm and Sm is used for this purpose. This alloy is molten at room temperature with surface tension > 500 dynes/cm, vapor pressure < 10-(-8) cm at 500 C and excellent wetting properties. This alloy can be utilized in valves, motion seals, flanged joints and for electrical contacts mounted in any position. Using ultrasonic soldering techniques without heat or flux this alloy is readily wetted on W, Mo, Ta, pyrex, quartz and certain ceramics. These materials will withstand the corrosive action of this alloy at at least 400 C. Some de-wetting has been observed with only the nonmetals at high temperatures. This de-wetting may be due to thermal decomposition of gallium oxide. Stainless steel is easily wetted, but is attacked at temperatures above 300 C. Copper and brass are attacked at room temperature."

The proper roof thickness to correspond with a given side wall thickness has been estimated fro experience with the 184 feet cyclotron, which has indicated that a roof of about 1 1/2 feet should accompany a wall of 5 feet, and a roof of 4 feet should accompany a wall of 15 feet. For the roof area involved, this should bring about the condition that down-scattered neutrons in the working areas are but a small fraction of the neutrons coming through the side walls.

The following report is based off of one of the author's lectures on the physics of plasma, or ionized gases, which was given on July 16, 1954.

Abstract: Experimentally measured promp-neutron decay constants for sub-critical systems are of considerable value as normalization data for calculations of prompt-neutron time constants. A method of measuring these decay constants with a pulsed neutron source, neutron detector and multi-channel time-delay analyzer has been developed and used on a number of fast-spectrum subcritical systems. An analysis of this method based on the one-energy group, one-delayed-neutron group reactor kinetic equations is presented and discussed. The curve of neutron flux versus time predicted by the kinetic equations is compared with the observed curve obtained with a 13.1-cm. diam. enriched-uranium sphere to indicate the application and limitations of the analysis.

The uptake of carbon dioxide by plant roots preparations has been demonstrated by various authors. In addition to confirming the fact of fixation, I have investigated the effect of a number of factors involved and the compounds in which the absorbed carbon appears, using carbon-14.

The following document was done under the auspices of the U.S. Atomic Energy Commission with the intention of analyzing air core cryogenic magnet coils and its usage in fusion research and high energy nuclear physics applications.

Abstract: "Preliminary design and experimental work aimed toward fabrication of large magnet coils with encapsulated sodium conductors is outlined. Aspects of cooling cycles are discussed along with heat transfer, thermal stability, and the mechanical reinforcement of such coils."

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