1,368 Matching Results

Search Results

prev Results: 25 - 48 next
open access

The Eight New Synthetic Elements

Description: In an early continuation of the investigation of the radioactive isotopes of element number 43 (technetium) Segre and Seaborg produced by the deuteron and neutron bombardment of molybdenum the isotope Tc{sup 99}, which they observed to decay by means of an isomeric transition with a half-life of 6.6 hours to a lower isomeric state with a half-life greater than 40 years. The upper isomeric state of this isotope was observed by Segre and C. S. Wu to be produced in the fission of uranium and more … more
Date: November 1, 1947
Creator: Seaborg, Glenn T.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
open access

Phosphorus Turnover and Photosynthesis

Description: The participation of phosphorus in biological oxidation-reduction reactions of the type found in glycolysis ADP + PO{sub 4}H{sup -} + 3-phosphoglyceraldehyde + DPN{sup +} = 3-phosphoglycerate{sup -} + 2H{sup +} + DPNH + ATP has suggested theories in which similar reactions are proposed for photosynthesis. In these theories the reducing power of photosynthesis is utilized not only for reduction of carbon dioxide but also, by means of coupled oxidations, for the generation of high-energy phosphat… more
Date: November 1, 1947
Creator: Aronoff, Sam & Calvin, Melvin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Diffraction Effects in Neutron Attenuation Measurements

Description: All errors due to diffraction effects in a neutron attenuation experiment are computed. Also a special experiment to measure the forward intensity of diffracted neutrons from lead and copper is described, and the results given. These agree with the theoretical values.
Date: November 1, 1947
Creator: McMillan, E. M. & Sewell, D. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Problems of Air-Borne Contamination in Handling of Pu F₄ Powders

Description: Abstract: Studies were made of the air-borne contamination present during the operation of reducing plutonium tetrafluoride powder to the metal. Equipment design changes were made and operation technique changes were made until the amount of contamination present during operations was well below tolerance levels.
Date: July 31, 1947
Creator: Kennedy, William R.; Dumrose, A. & Ludwig, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Fraunhofer Diffraction Pattern Produced by a Slit of Varying Width and its Application to High Speed Cameras

Description: Abstract: "A theoretical and experimental investigation is made of the diffraction pattern produced by a slit, whose aperture varies uniformly from a constant value A to zero. The results of this investigation are applied to a proposed high speed camera. It is shown that diffraction effects are very serious and cannot be neglected. It seems, unless the suggested design of this high speed camera is changed, the camera will be of little use for accurate measurements, and photographs will show too… more
Date: November 11, 1947
Creator: Geiger, F. E. & Brixner, Berlyn
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Method for Rolling Uranium Foil

Description: "This report gives briefly a rather simple method for fabricating foils from uranium buttons. Two log sheets one of a U-238 run and one of a U-255 run are given."
Date: October 21, 1947
Creator: Bernard, George L., (Jr.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Beta-Counting Methods Applied to the Determination of Uranium in Low-Grade Ores

Description: The following report covers investigations on the application of the beta counter as an analytical tool for use in experiments on the extraction and concentration of uranium from low-grade (.005-.02 % uranium) shale and phosphate rock ores.
Date: July 1947
Creator: Doig, J. R.; Igelsrud, Iver; Nelson, H. R. & Schwartz, C. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Survey of Los Alamos and Pueblo Canyon for Radioactive Contamination and Radio Assay Tests Run on Sewer-Water Samples and Water and Soil Samples Taken From Los Alamos and Pueblo Canyons

Description: "Report of the Survey of Los Alamos and Pueblo Canyon for radioactive contamination and radioassay tests run on sewer water samples and water and soil samples taken from Los Alamos and Pueblo Canyons." The objective of this report was to determine the extent and sources of radioactive contamination in the areas studied.
Date: February 20, 1947
Creator: Kingsley, William H.; Fox, Alvin; Tribby, J. F. & Doner, Elmer
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Preliminary Report on Existing Active Particle Hazard-200 Areas

Description: "Recent surveys by the Health Instrument Section have disclosed the presence of many small radioactive spots on ground surfaces in the T and B plant areas. Investigation has shown that representative samples of the spots when mechanically separated invariably end in a single radioactive particle."
Date: October 22, 1947
Creator: Mickelson, M. L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Investigations on Reductions of Friction on Wings, in Particular by Means of Boundary Layer Suction

Description: Memorandum presenting investigation on reductions of friction on wings, especially by means of boundary-layer suction. The report is broken up into several sections, including: causes of transition, laminar profiles with the transition taking place, laminar boundary-layer suction, investigation of the laminar pressure increase, investigation of the slot flow for laminar boundary-layer suction with single slots, tests about keeping a boundary layer for high Reynolds laminar with the aid of bound… more
Date: August 1947
Creator: Pfenninger, Werner
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A flight investigation to increase the safety of a light airplane

Description: Report presenting information about a series of modifications incorporated into light airplanes to increase safety, including decreasing the wing incidence, increasing the wing washout, increasing the area and aspect ratio of the horizontal and vertical tails, moving the elevators out of propeller slipstreams, depressing the thrust axis, and limiting the rudder travel. The new inherent safety characteristics and effects on the airplane's performance are provided.
Date: March 1947
Creator: Hunter, P. A. & Vensel, J. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Effect of Centrifugal Force on the Elastic Curve of a Vibrating Cantilever Beam

Description: Report presenting the results of a study to determine the effect of rotation on the dynamic-stress distribution in vibrating cantilever beams. Both theoretical and experimental results are obtained by means of stroboscopic photographs and strain gauges. Both types of results indicated that the introduction of centrifugal force had no effect on the maximum dynamic-stress locations in a vibrating cantilever beam fixed at the center of rotation within the investigated speed range.
Date: February 1947
Creator: Simpkinson, Scott H.; Eatherton, Laurel J. & Millenson, Morton B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Boundary-Induced Upwash for Yawed and Swept-Back Wings in Closed Circular Wind Tunnels

Description: Report presenting a determination of the tunnel-induced velocities for yawed and swept-back airfoils in a closed circular wind tunnel. Calculations were performed for elemental horseshoe vortices with one tip of the bound vortex on the tunnel axis for a range of yaw angles and bound-vortex lengths.
Date: May 1947
Creator: Eisenstadt, Bertram J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Data on Optimum Length, Shear Strength, and Tensile Strength of Age-Hardened 17S-T Machine-Countersunk Rivets in 75S-T Sheet

Description: Report presenting a series of tensile-strength and shear-strength tests made on age-hardened 17S-T rivets machine-countersunk in 75S-T sheets. The results of the tests indicated that the joints can be made satisfactorily with regard to both flushness and strength if the ratio of buck to diameter is kept to a certain value.
Date: March 1947
Creator: Schuette, Evan H. & Niles, Donald E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Flight Measurements of Helicopter Blade Motion With a Comparison Between Theoretical and Experimental Results

Description: Note presenting photographic records of the behavior of a blade in flight as obtained with a conventional single-rotor helicopter. The results of the measurements of flapping motion, in-plane motion, and blade distortions are presented for selected conditions of flight at tip-speed ratios ranging from 0.12 to 0.25. Plots of blade twisting and blade bending in the plane of flapping are presented for a sample case.
Date: April 1947
Creator: Myers, Garry C., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The streamline pattern in the vicinity of an oblique airfoil

Description: "A method for determining the streamwise flow pattern of a nonviscous incompressible fluid about an oblique airfoil from the corresponding flow pattern about the airfoil in normal position is presented and illustrated in two examples. The method can be extended to account approximately for compressibility effects by applying the Prandtl-Glauert correction factor to the flow pattern that is normal to the leading edge of the airfoil. The method is expected to be useful in determining the shape of… more
Date: March 1947
Creator: Watkins, Charles E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Flight Tests of a Helicopter in Autorotation, Including a Comparison With Theory

Description: Note presenting the results of glide performance tests conducted on a test helicopter with its original production blades in the autorotation condition. The data was reduced to coefficient form, and performance at standard sea-level conditions were calculated.
Date: April 1947
Creator: Gessow, Alfred & Myers, Garry C., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Experimental and calculated characteristics of several NACA 44-series wings with aspect ratios of 8, 10, and 12 and taper ratios of 2.5 and 3.5

Description: The aerodynamic characteristics of seven unswept tapered wings were determined by calculation from two-dimensional data and by wind-tunnel tests in order to demonstrate the accuracy of the calculations and to show some of the effects of aspect ratio, taper ratio, and root thickness-chord ratio. The characteristics were calculated by the usual application of the lifting-line theory which assumes linear section lift curves and also by an application of the theory which allows the use of nonlinear… more
Date: May 1947
Creator: Neely, Robert H.; Bollech, Thomas V.; Westrick, Gertrude C. & Graham, Robert R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen