An investigation was made of a series of binary americium alloys with AB$sub 2$ stoichiometry (B = Al, Co, Fe, Rh and Ru) prepared from the $sup 243$Am isotope. The C-15 (MgCu$sub 2$-type) structure appears in AmAl$sub 2$, AmCo$sub 2$, AmFe$sub 2$, and AmRh$sub 2$, whereas AmRu$sub 2$ is isostructural with AmOs$sub 2$ which has the C-14 (MgZn$sub 2$-type) structure. The magnetic properties of the cubic americium laves phases were studied by means of magnetization and nuclear gamna-ray resonance (Moessbauer effect) measurements between 2.5 and 300$sup 0$K. All the cubic Laves phases studied, except AmFe$sub 2$, exhibit almost temperature-independent paramagnetism. The AmFe$sub 2$ sample is ferromagnetic with an estimated Curie temperature of approximately 400$sup 0$K. The hyperfine field at the Am site in all the compounds is small. The bulk magnetic moment of AmFe$sub 2$ (approximately 3 $mu$/sub B//F.U.) is thus associated only with the Fe atoms. The magnetic properties of the compounds are consistent with the assumption that the Am ion is in the +3 state (5f6). (auth)

Recent research involving the direct computer simulation of plastic deformation through planar dislocation glide suggests that plastic inhomogeneities such as the formation and growth of discrete slip bands are an inherent feature of deformation through glide. The sources of glide inhomogeneity are described and the influence of temperature, microstructural barriers, and applied stress on the heterogeneity of deformation in idealized crystals is discussed.

It is shown that there are several substantive errors in a previous work on a cosmic ray event which is consistent with the hypothesis that it was caused by a magnetic monopole. It is shown that the data points fit to the hypothesis that the responsible particle is a platinum nucleus fragmenting to osmium and then to tantalum. (JFP)

Measurements of the deHaas-vanAlphen effect were performed in the intermetallic compounds URh$sub 3$ and UIr$sub 3$. Complex spectra were observed in both materials. Effective mass measurements were made for several orbits in URh$sub 3$ and values as large as 5.3 m$sub 0$ were observed. The relatively complete data in URh$sub 3$ are consistent with a complex multiply-connected Fermi surface which is in qualitative agreement with band structure calculations. The largest frequency branches in UIr$sub 3$ appear to have the same topology as their corresponding branches in URh$sub 3$. In addition, a number of closed low- mass surfaces exist in UIr$sub 3$ and are discussed in terms of the calculations for URh$sub 3$. (auth)

None

None

Several techniques for using direct electron-pumping of gas lasers are reviewed. The primary objective is to categorize pump geometries and to give guidelines for gun selection and pulser design. Examples and application of pump technology are given. (auth)

The literature on cryogenic hydrogen isotopes from 4.2 to 25$sup 0$K is reviewed for triple points, vapor pressures, liquid viscosities, surface tensions, and liquid and solid densities. Data are extrapolated to yield values for DT. Empirical equations are given for all isotopes for each property. At the estimated 19.71$sup 0$K triple point of 1:1 D-T in D$sub 2$-DT-T$sub 2$ solution, the estimated properties are: vapor pressure, 19,420 Pa (145.7 torr); viscosity 550 x 10$sup -7$ Pa.s; surface tension 4.23 x 10$sup -3$ N/m; liquid density, 0.0446 x 10$sup 6$ mol/m$sup 3$ (224 Kg/m$sup 3$); solid density, 0.051 x 10$sup 6$ mol/m$sup 3$ (256 Kg/m$sup 3$); and shrinkage upon freezing, -13 vol percent. At 4.2$sup 0$K, estimated values are: vapor pressure, 2.4 x 10$sup -10$ Pa (1.8 x 10$sup -12$ torr) and solid density, 0.053 x 10$sup 6$ mol/m$sup 3$ (267 Kg/m$sup 3$). (auth)

The Fort St. Vrain program has progressed through construction, preoperational testing, fuel loading, initial criticality, and operational testing at power levels up to 2 percent related power. To date, all tests necessary before the rise to full power have been completed, and the rise-to- power program is expected to be resumed again in late 1975. Major plant systems, including the prestressed concrete reactor vessel and circulators, have demonstrated adequate performance. Extensive tests on the reactor core at zero power and up to 2 percent power have demonstrated the accuracy in the design predictions of such core characteristics as critical rod position, control system worths, neutron flux distributions, and temperature coefficients. Gaseous fission product release measurements to date have confirmed the extensive analytical estimates. 6 references (auth)

The difficult task of removing large pieces of highly contaminated equipment from an obsolete plutonium-239 facility was completed in a seven-month operation that included structural alteration of the process building. Detailed job planning, job execution and contamination control were major factors in accomplishing the task. (auth)

The expansion of ballistic gun range facilities at LLL has introduced state-of-the-art diagnostic techniques to glovebox-enclosed ballistic guns systems. These enclosed ballistic ranges are designed for the study of one- dimensional shock phenomena in extremely toxic material such as plutonium. The extension of state-of-the-art phtographic and interferometric diagnostic systems to glovebox-enclosed gun systems introduces new design boundaries and performance criteria on optical and mechanical components. A technique for experimentally evaluating design proposals is illustrated, and several specific examples (such as, target alignment, collateral shrapnel damage, and soft recovery) are discussed. (auth)

High-purity MgO crystals grown at ORNL were irradiated in the LLL 14.8- MeV Rotating Target Neutron Source (RTNS) to doses varying from 1.8 x 10$sup 15$ to 5.7 x 10$sup 17$ n/cm$sup 2$. The optical absorption spectra of these crystals resembled those irradiated in fission reactors and exhibited bands principally at 4.95, 3.5, 2.2, and 1.3 eV. The band with the largest absorption coefficient, that at 4.95 eV, is due to anion vacancies. The bands at 3.5 and 1.3 eV, attended by zero-phonon lines at 3.430 and 1.187 eV respectively, are attributed to different optical transitions of anion divacancies. The investigations indicate that the net production rates of the point defects resulting from irradiations with 14.8-MeV neutrons are about twice those resulting from fission neutrons in the Oak Ridge Reactor (ORR). This ratio is in reasonable accord with theoretical estimates based on damage energy calculations. (auth)

In this work, along with a previous paper three possible uses of 14-MeV deuterium--tritium fusion neutrons are investigated: energy production, neutron multiplication, and fissile-fuel breeding. The results presented include neutronic studies of fissioning and nonfissioning thorium systems, tritium breeding systems, various fuel options (UO/sub 2/, UC, UC/sub 2/, etc.), and uranium as well as refractory metal first-wall neutron-multiplying regions. A brief energy balance and an estimate of potential revenues for fusion devices are given to help illustrate the potentials of these designs.

Helium in very low concentration (less than 1 atomic ppB) has been introduced into type 304 stainless steel by radioactive decay of dissolved tritium. Release of this helium during subsequent annealing was monitored with a high sensitivity mass spectrometric gas analyzer. With isochronal annealing, helium is released in two temperature ranges, one near 300$sup 0$C and the other between 800$sup 0$C and the melting point. The latter release is interpreted as attributable to helium gas bubbles. The release near 300$sup 0$C was studied isothermally between 150 and 300$sup 0$C and is analyzed in terms of two stages of exponential decay. The fast and slow release stages have relaxation times near 10$sup 2$ and 10$sup 3$ s, respectively, and the fast release accounts for roughly 85 percent of the total release at low temperature. From an analysis of the temperature dependence of the release rate, it is concluded that volume diffusion is the controlling mechanism for the outgassing. (auth)

We have studied uranium as a getter material under varying flow conditions using a uranium trap designed to remove tritium from inert gases. The uranium trap can remove any hydrogen isotope from an inert gas. We used mixtures of deuterium in argon at room temperatures. In the case of tritium, recovery is effected by heating the trap. A special segmented trap was designed to prevent channeling and to promote maximum reaction rates when gas flows through it. The gas mixtures were sampled at the trap inlet and outlet and were analyzed by a mass spectrometer. The results are expressed as a purification factor, which is the ratio of deuterium concentration at the inlet of the uranium trap to the concentration at the outlet. Purification factors vary inversely with both the ratio of deuterium to uranium already contained in the trap and with the rate of flow of gas through the trap. The effects of varying inlet deuterium concentrations on purification factors are also discussed. (auth)

The work done with element 106 is reviewed, and a new experiment which bears on the properties of the isotope of mass 260 with atomic number 104 is discussed. It is noted that in the case of element 106 a link is demonstrated to the granddaughter as well as the daughter. (JFP)

A semiconductor detector x-ray spectrometer has been constructed for the analysis of elements in air particulate specimens. The excitation radiation is provided, either directly or indirectly, using a low power (40 watts) Ag anode x- ray tube. Less than 100 ng for most of the elements in the range Mg $Yields$ Zr, Pb are easily detected within two 1-minute counting intervals. A calibration technique for light element analysis and an experimental method which compensates for particle size effects are discussed. (auth)

None

None

The Savannah River Plant (SRP) has routinely and continuously monitored the local environment (land, water, air, flora, and fauna) since 1951. As part of this intensive program, a three-part study was made to assess the tritium migration from an onsite burial ground for solid nuclear wastes and the resulting dose-to-man. A major source of tritium is buried, massive, Li-Al residues (referred to as melts) from the thermal extraction step in the SRP tritium production process. A melt with its extraction crucible and lid were immersed in water to measure the amounts of tritium released as HTO and HT to the water and to air. The result was a rapid release of 23 curies, of which approximately 99 percent was HTO that remained in the immersion water, and 1 percent was HT that passed into the air. (auth)

The following topics were considered at the workshop: perturbation of the natural sulfur cycle by human activity; ecosystem responses to a given environmental dose of sulfur compounds; movement of sulfur compounds within the atmosphere; air quality models; contribution of biogenic sulfur compounds to atmospheric burden of sulfur; production of acid rain from sulfur dioxide; meteorological processes; and rates of oxidation of SO/sub 2/ via direct photo-oxidation, oxidation resulting from photo-induced free radical chemistry, and catalytic oxidation in cloud droplets and on dry particles. (HLW)

High purity copper foils were irradiated with 14.8-MeV neutrons from the rotating target neutron source facility at LLL. The average energy of the neutrons was 14.75 +- 0.1 MeV, and the average fluence was 7.0 x 10$sup 16$ n/ cm$sup 2$. After irradiation each foil was heated to the melting point and the released helium was measured by a mass spectrometer of special design. Isochronal heating was carried out on several samples to establish the type and temperature of maximum release. Calculated cross sections from the literature for the (eta,$alpha$) and (eta,eta'$alpha$) nuclear reactions were used, and the predicted amount of helium was consistently about 0.5 of that actually measured. Because there is very little data on helium generation in metals irradiated with high energy neutrons, these results are important and will be related to potential CTR materials. (auth)

A new gun system is being constructed at the Lawrence Livermore Laboratory for studies of the behavior of toxic materials under shock-loaded conditions. Due to the extreme toxicity of some materials, such as plutonium, the entire gun system must be enclosed in gloveboxes. Some of the experimental requirements that affected the design of the system, various diagnostic techniques that will be employed with the system, and some details of the final design that is presently under assembly are presented. (auth)

Specifications, operation, characteristics, cost, and experience with the NAL 15-ft bubble chamber are described. Beam availability and some experimental proposals are discussed. (WHK)