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Army Airfield Pavement Evaluation, Report 4: Simmons Army Airfield, Fort Bragg, North Carolina

Description: "This report describes studies and analyses made to determine the load-carrying capacities of the pavements at Simmons Army Airfield with respect to various aircraft landing gear assemblies and pavement life categories. The report includes data obtained from design specifications, in-place and laboratory tests performed during construction of the pavements, and in-place and laboratory tests performed for evaluation purposes" (p. 1).
Date: January 1958
Creator: Waterways Experiment Station (U.S.)
Partner: UNT Libraries Government Documents Department

Geology of the Mississippi River Deltaic Plain, Southeastern Louisiana: Volume 1

Description: "The purpose of this report is to consolidate data gathered by the Corps of Engineers in various geologic investigations, and to augment this material with pertinent information garnered from the extensive investigations and studies [of the Mississippi River deltaic plain and its associated offshore area]" (p. 1). The report focuses primarily on those materials that are most important from an engineering standpoint.
Date: July 1958
Creator: Waterways Experiment Station (U.S.)
Partner: UNT Libraries Government Documents Department

PAR Loop Schedule Review

Description: The schedule for the installation of the PAR slurry loop experiment in the ┬ĚSouth Facility af the ORR has been reviewed and revised. Changed design philosophy to include maintainability of the loop auxiliaries required extension of the main construction period to the end of,June, with a three month period ending in September, for test and run in during which construction will be completed.
Date: February 28, 1958
Creator: Schaffer, Jr. & W.F.
Partner: UNT Libraries Government Documents Department

PAR Loop Schedule Review

Description: The status of the overall design, fabrication, and installation of the component items of the PAR loop experiment in the ORR is reviewed.
Date: January 15, 1958
Creator: Schaffer, Jr. & W.F.
Partner: UNT Libraries Government Documents Department

PAR Loop Schedule Review

Description: The schedule for the installation of the PAR slurry loop experiment in the South Facility of the ORR has been reviewed and revised. The design, fabrications and Installation is approximately two weeks behind schedule at this time due to many factors; however, indications are that this time can be made up. Design is estimated to be 75% complete, fabrication 32% complete and installation 12% complete.
Date: April 30, 1958
Creator: Schaffer, Jr. & W.F.
Partner: UNT Libraries Government Documents Department

TWO-GROUP CONSTANTS FOR REACTOR MATERIALS

Description: In order to facilitate reactor design studies a compilation of calculated two-group constants averaged over the infinite-medium flux produced by a fission source was made for approximately 80 materials of interest to reactor engineers. A comparison with available experimental age measurements is included. (auth)
Date: May 1, 1958
Creator: Stanley, M.J.
Partner: UNT Libraries Government Documents Department

CHEMICAL EQUILIBRIA AND REACTION RATES FOR HYDROFLUORINATION OF UO$sub 2$ FROM "AMMONIUM DIURANATE" AND FROM UO$sub 3$

Description: Reaction rates for the hydrofluorination of UO/sub 2/ derived from two widely different source materials (sulfated pot-denitrated UO/sub 3/ and "ammonium diuranate," (ADU)) were determined in a thermobalance over a wide range of temperatures (460 deg F to 1150 deg F) and with several HF--H/sub 2/O gas phase mixtures varying from 20 to 100 per cent HF. These data were then organized to yield single plots for each type of feed material. From these plots, maximum instantaneous reaction rates may be determined. These values may be applied to problems dealing with the estimation of minimum retention times required for hydrofluorination in counter-current gas-solid contactors. In addition to the rate studies, the thermobalance was used to establish temperatures corresponding to equilibrium in the system, UO/sub 2/(s)-- UF/sub 4/(s)--HF(g) --H/sub 2/O(g), at several selected HF/H/sub 2/O ratios in the gas phase. These data, together with thermodynamic theory, were employed to calculate equilibrium conditions at total pressures other than one atmosphere and for various dilutions of the gas phase with an inert gas. (auth)
Date: March 12, 1958
Creator: Briggs, G.G.
Partner: UNT Libraries Government Documents Department

ECONOMICS OF NUCLEAR AND CONVENTIONAL TANKERS

Description: The work performed augments that portion of ASAE-S-5 devoted to a study of the economics of nuclear tankers by presenting economic data on three additional tanker sizes, each driven at three different speeds. Some of the previous dath are repeated to facilitate direct comparison of the different ship sizes. Operating costs and return on investment are tabulated for all six ship sizes on three specific trade routes. (W.D.M.)
Date: October 10, 1958
Creator: Gordon, J.J. & Buck, K.E.
Partner: UNT Libraries Government Documents Department

THE APPLICATION OF THE CHIP AND SHOT METHODS TO THE PREPARATION OF HOMOGENEOUS ALLOYS

Description: Chip method experiments were performed for the preparation of Th - 9 wt.% U, U - 10 wt.% Nb, and Al--16 wt.% U - 0.2 wt.% B alloys. The work on Th-9 wt.% U indicated that the technique was applicable with oniy slight impairment of mechanical properties and slight increase of oxygen content. Experiments on U-10 wt.% Nb to produce a more corrosion-resistant alloy were not successful. The potential use of the chip method in fabricating alloys with a burnable poison such as boron appeared feasible. An aluminum alloy containing 16 wt.% U and 0.2 wt.% B showed good homogeneity. The shot method was used on an alloy of Al-25 wt.% U. The homogeneity and the mechanical properties of this alloy, when extruded, were superior to those of similar alloys produced by conventional melting and casting. Preliminary work on the blending of master alloys of a burnable poison (i.e., boron) with an aluminumuranium alloy indicated the feasibility of obtaining a homogeneous alloy with good mechanlcal properties. (auth)
Date: September 18, 1958
Creator: Kneppel, D.S.
Partner: UNT Libraries Government Documents Department

THE METABOLSIM AND TOXICITY OF RADIUM-223 IN RATS

Description: This report covers studies of the excretion and retention of 'tracer' and toxic doses of the 11.2-day Ra{sup 223} isotope, its acute toxicity (organ weight changes, gross and microscopic pathology, and Fe{sup 59} utilization by the bone marrow), and long-term histopathological changes and alterations in the hemogram.
Date: February 21, 1958
Creator: Durbin, Patricia; Durbin, Patricia W.; Asling, C. Willet.; Jeung, Nylan; Williams, Marilyn H.; Post, James. et al.
Partner: UNT Libraries Government Documents Department

COMPARISON OF COMPUTED CENTERLINE DOSE RATES FROM DIFFERENT AREAS OF A SOURCE PLATE

Description: A shield fixture that consists of a slab of iron with a cylindrical hole into which plugs of various materials can be inserted is described. Computations made to determine the effect of source-plate size on centerline dose rates are described, and incremental dose contributions from various annular sections of the source plate are presented. Plugs of iron, aluminum, and lead were used in the computations. (auth)
Date: November 1, 1958
Creator: Casper, A.W. & Carver, J.G.
Partner: UNT Libraries Government Documents Department

VELOCITY OF SOUND IN WATER CONTAINING GAS BUBBLES

Description: The velocity of sounmd in water containing bubbles of hydrogen gas is computed as a function of the volume fraction of gas for various bubble sizes. Results indicate that the marked reduction in sound velocity caused by the presence of gas voids is not as great if the gas is present as very small bubbles. The results are used in qualitative observations concerning inertial pressures in fast excursions in the KEWB reactor. The qualitative conclusions are listed. (J.R.D.)
Date: November 1, 1958
Creator: Hetrick, D.L.
Partner: UNT Libraries Government Documents Department

A GAS SHAFT SEAL FOR THE HNPF SODIUM PUMP

Description: Lip type, oil labyrinth gas shaft seals were tested for use on Hallam Power Reactor sodium pumps with a 5-in.diameter rotating shaft. The seals were not recommended for use owing to excess helium leakage and short life. (C.J.G.)
Date: June 30, 1958
Creator: Admire, B.W. & Nayor, F.S.
Partner: UNT Libraries Government Documents Department

The Metabolism of 2-Caroboxy-4-Ketopentitol Diphosphate

Description: 2-Carboxy-4-ketopentitol is converted enzymatically by a cell-free preparation from spinach leaves into a substance undergoing acid-lactone interconversion. This substance has no phosphate or letone group and is probably a dicarboxylic, six-carbon sugar acid or the saccharic or saccharinic acid type. The significance of these findings with regard to the metabolic role of 2-carboxy-4-ketopentitol diphosphate is discussed.
Date: July 15, 1958
Creator: Moses, V. & Calvin, M.
Partner: UNT Libraries Government Documents Department

Element No. 102

Description: By the use of a radically new method they have succeeded in identifying unambiguously an isotope of element 102. In other careful experiments conducted over a period of many months they find that they are unable to confirm the element 102 discovery work of Fields et al. reported in 1957. The experiments at Berkeley were performed with the new heavy ion linear accelerator (HILAC) over a period of several weeks and culinated the chemical identification of an isotope of fermium (Fm{sup 250}) as the daughter of an alpha-particle-emitting isotope of element 102 (102{sup 254}). The method used to detect the isotope of element 102 was essentially a continuous milking experiment wherein the atoms of the daughter element 100 were separated from the parent element 102 by taking advantage of the recoil due to the element 102 alpha particle decay. The target consisted of a mixture of isotopes of curium (95% Cm{sup 244} and 4.5% Cm{sup 246}) mounted on a very thin nickel foil. The target was approximately 0.5 mg/cm{sup 2} thick and was covered with 75 {micro}gm/cm{sup 2} aluminum to prevent curium 'knockover'. The curium was bombarded with mono-energetic C{sup 12} ions at energies from 60 to 100 Mev. The transmuted atoms were knocked into helium gas to absorb the considerable recoil energy. It was found that with a sufficient electric field strength practically all of these positively charged atoms could be attracted to a moving negatively charged metallic belt placed directly beneath the target. These atoms would then be carried on this conveyer belt under a foil which was charged negatively relative to the belt. Approximately half of the atoms undergoing alpha decay would cause their daughter atoms to recoil from the surface of the belt to the catcher foil. The catcher foil was cut transversely to the direction ...
Date: June 4, 1958
Creator: Ghiorso, A.; Sikkeland, T.; Walton, J.R. & Seaborg, G.T.
Partner: UNT Libraries Government Documents Department

Energy Conversion in Photosynthetic Processes

Description: The concepts of solid-state photophysics are applied to biological materials, especially particulate matter derived from green plants. Photoinduced electron-spin resonance signals have been observed in isolated chloroplasts and other green plant materials; their growth time is not affected by reducing the temperature to -140 C. The luminescence of these materials has also been investigated under a variety of conditions. The results of these studies have been shown to be consistent with a mechanism involving the recombination of electrons and holes trapped in a quasi-crystalline lattice. Some details of such a mechanism have been proposed that suggest the mode of entry of the light energy into the photosynthetic pathway.
Date: March 10, 1958
Creator: Tollin, Gordon; Sogo, Power B. & Calvin, Melvin
Partner: UNT Libraries Government Documents Department

ENERGY RECEPTION AND TRANSFER IN PHOTOSYNTHESIS

Description: The basic information about the path of carbon in photosynthesis is reviewed together with the methods that were used to discover it. This has led to the knowledge of what is required of the photochemical reaction in the form of chemical species. Attention is then directed to the structure of the photochemical apparatus itself insofar as it is viewable by electron microscopy, and some principoles of ordered structure are devised for the types of molecules to be found in the chloroplasts. From the combination of these, a structure for the grana lamella is suggested and a mode of function proposed. Experimental test for this mode of function is underway; one method is to examine photoproduced unpaired electrons. This is discussed.
Date: September 23, 1958
Creator: Calvin, Melvin
Partner: UNT Libraries Government Documents Department

The Nonphotosynthetic Fixation of Carbon Dioxide by ThreeMicro-Organisms

Description: Studies by Lynch and Calvin (1952,1953) have established the nature of the compounds incorporating C{sup 14} nonphotosynthetically from C{sup 14}O{sub 2} in thirteen microorganisms: a yeast, a protozoan, two water moulds, one slime mould, three algae, three bacteria, and the green flagellate Euglena Gracilis. With the exception of H. gracilis, and of Lactobacillus cassi which fixed no detectable amounts of carbon dioxide, all these organisms fixed carbon dioxide into amino and organic acids derived from the tricarboxylic acid cycle, and into a few other compounds in individual cases (tyrosine, phenylalanine, polysaccharides [probably glucose polymers], acetic acid and butyric acid). The authors concluded that the presence of C{sup 14} in almost all these compounds could be accounted for by the carboxylation of pyruvate to yield oxalacetic or malic acids, followed by transaminase reactions. In E. gracilis, however, considerable quantities of activity also appeared in phosphorylated compounds in the dark, especially in the sugar monophosphates, phosphoglyceric acid, and phosphoenolpyruvic acid. Only with this organisms was a kinetic study performed to determine the identity and degree of labeling of the compounds containing C{sup 14} after varying periods of time. It was not stated definitely by which route carbon dioxide entered the photosynthetic intermediates, but it was implied that it was incorporated directly into phosphoglyceric acid, and that the energy for this process, which in photosynthesis is derived from sunlight, and was provided by respiration or fermentation. Certain aspects of these presumptions however, do not adequately account for all the experimental data.
Date: July 1, 1958
Creator: Holm-Hansen, O.; Moses, V. & Calvin, M.
Partner: UNT Libraries Government Documents Department

Nuclear Thermodynamics of the Heaviest Elements. II

Description: The masses of the isotopes of the heaviest elements have been calculated from known decay data in the region, extended by means of decay energies calculated from closed decay-energy cycles and estimated from the systematics of alpha and beta decay energies. The absolute values of the masses are based on the mass-spectrometrically determined mass of Pb{sup 208} and a few measured neutron binding energies. The half-life systematics of alpha decay and spontaneous fission are also presented, and some predictions of the properties of as yet undiscovered nuclides are made.
Date: January 1, 1958
Creator: Foreman Jr., Bruce M. & Seaborg, Glenn T.
Partner: UNT Libraries Government Documents Department

The Nurture of Creative Science and the Men who Make It

Description: This report describes the development of work that began as an investigation of photosynthesis and that continues in this direction, but which has as a new product some entirely strngly results. Photosynthesis, the process upon which all life on earth today is ultimately dependent, achieves the conversion of electromagnetic energy from the sun into chemical energy in the form of plant material by the reduction of CO{sub 2} from the atmosphere with the liberation of O{sub 2} to the atmosphere. It has been possible to describe in some detail the way in which the plant accomplishes the reduction of carbon dioxide, using radioactive carbon as a tracer. The status of the present knowledge, and how they attained it, together with some prospectus of the future and what we can look forward to, is the principal theme of this discussion.
Date: May 1, 1958
Creator: Calvin, Melvin
Partner: UNT Libraries Government Documents Department

High-Energy Physics with Hydrogen Bubble Chambers

Description: Five years ago, our laboratory undertook to adapt the bubble chamber, newly invented by Glaser, to operation with liquid hydrogen, and in large sizes. It was hoped taht this development would yield important new experimental data when the Bevatron was completed. Accompanying papers by other members of the hydrogen bubble chamber group describe the various chambers built in the five year period and the asociated data-reduction apparatus that is needed for efficient utilization of the chambers. Experiments with the 10-cm chamber have yielded interesting data on the interaction of 300-Mev bremsstrahlung radiation with protons, and have shown that a hydrogen bubble chamber is a convenient neutron spectrometer in the 10- to 25-Mev range, the full width (at half maximum) of the 14-mev neutron line from T + D is 1 Mev. This paper, however, describes only those experiments performed at the Bevatron with chambers of 25 cm and 40 cm.
Date: October 14, 1958
Creator: Alvarez, Luis W.
Partner: UNT Libraries Government Documents Department

Spallation-Fission Competition in Heaviest Elements; HeliumIon-Induced Reactions in Uranium Isotopes

Description: A radiochemical study of fission and spallation products produced by bombardment of U{sup 233}, U{sup 235}, and U{sup 238} with 18-46 Mev helium ions has been made. As in the case of similar studies using isotopes of plutonium as targets, most of the reaction cross section is taken up by fission. Also, the pronounced increase of the total cross section for ({alpha},xn) reactions with increasing mass number of the target that was observed for plutonium targets is observed for uranium targets.
Date: January 1, 1958
Creator: Vandenbosch, R.; Thomas, T.D.; Vandenbosch, S.E.; Glass, R.A. & Seaborg, G.T.
Partner: UNT Libraries Government Documents Department