UNT Libraries Government Documents Department - 1,889 Matching Results

Search Results

prev Results: 901 - 924 next
open access

AN INVESTIGATION OF THE ISOTOPES OF AMERICIUM AND CURIUM

Description: Isotopes of americium and curium with mass numbers less than 242 have been produced by cyclotron bombardment techniques, and several of their nuclear properties have been investigated. The partial alpha half-lives of Am{sup 239}, Cm{sup 241}, and Cm{sup 240} and the partial half-life for spontaneous fission of Cm{sup 240} were measured. The alpha decay daughter of Cm{sup 238} was found and evidence for the discovery of Am{sup 237} (an {approx}1 hour electron capture activity) and Cm{sup 239} (a… more
Date: June 1, 1952
Creator: Higgins, Gary Hoyt.
Item Type: Refine your search to only Thesis or Dissertation
open access

An Investigation of the Isotopes of Americium and Curium

Description: Isotopes of americium and curium with mass numbers less than 242 have been produced by cyclotron bombardment techniques, and several of their nuclear properties have been investigated. The partial alpha half-lives of Am(239), Cm(241), and Cm(240) and the partial half-life for spontaneous fission of Cm(240) were measured. The alpha decay daughter of Cm(238) was found and evidence for the discovery of Am(237) (an -1 hour electron capture activity) and Cm(239) (an -10 hour electron capture activ… more
Date: June 1952
Creator: Higgins, Gary Hoyt
Item Type: Refine your search to only Report
open access

Investigation of the Low-Speed Aerodynamic Characteristics of a Variable-Sweep Airplane Model With a Twisted and Cambered Wing

Description: Report presenting an investigation to determine the low-speed characteristics of a variable-sweep airplane model with a twisted and cambered wing. The wing was designed to have a uniform load distribution at a Mach number 1.10 and a lift coefficient of 0.25 and 50 degrees sweep. Results regarding lift characteristics, drag characteristics, lift-drag ratio, pitching-moment characteristics, dynamic pressure and downwash at the tail, effect of flaps, and lateral stability characteristics are provi… more
Date: February 1, 1952
Creator: Kemp, William B., Jr.; Becht, Robert E. & Few, Albert G., Jr.
Item Type: Refine your search to only Report
open access

An Investigation of the Low-Speed Longitudinal Stability Characteristics of a Swept-Wing Airplane Model With Two Modifications to the Wing-Root Plan Form

Description: Report presenting a wind-tunnel investigation to determine the effects of two wing-root leading-edge plan-form modifications, including a notched leading-edge fillet and a rounded leading-edge fillet, on the low-speed longitudinal stability characteristics of an airplane model with a 50.7 degree sweptback wing. Results regarding stability at zero lift, variation of stability with lift coefficient, and lift and drag characteristics are provided.
Date: July 11, 1952
Creator: Kemp, William B., Jr.
Item Type: Refine your search to only Report
open access

An Investigation of the Stream-Tube Power Losses and an Improvement of the Diffuser-Entrance Nose in the Langley 8-Foot Transonic Tunnel

Description: Report presenting surveys of the distribution of total pressure, total temperature, and static pressure at a number of stations in the slotted test section and diffuser of the transonic tunnel with early and improved diffuser-entrance noses installed at the ends of the slots. Results regarding power losses with the original diffuser-entrance nose, development of revised diffuser-entrance noses, and energy losses in the tunnel with the final diffuser-entrance nose are provided.
Date: July 30, 1952
Creator: Whitcomb, Richard T.; Carmel, Melvin M. & Morgan, Francis G., Jr.
Item Type: Refine your search to only Report
open access

Investigation of the Structural Damping of a Full-Scale Airplane Wing

Description: "An investigation to determine the structural damping characteristics of a full-scale airplane wing was conducted by the shock-excitation method wherein the wing was loaded to a predetermined deflection and the load suddenly released. The test specimen vibrated at its fundamental bending frequency of 1.69 cycles per second. Only the first 2 or 3 cycles showed any indication of a higher frequency being superimposed upon the fundamental bending frequency. The damping was found to increase from ab… more
Date: February 1952
Creator: Fearnow, Dwight O.
Item Type: Refine your search to only Report
open access

An investigation of the subsonic speed range of a full-span and a semispan model of a plane wing and of a cambered and twisted wing, all having 45 degrees of sweepback

Description: Report presenting a wind-tunnel investigation of two full-span and two semispan models with 45 degrees of sweepback, an aspect ratio of 5.5, and a taper ratio of 0.53. The lift and drag data obtained from tests of the semispan agreed well with data obtained on the full-span model. Results regarding a comparison of the data for the full-span and semispan models, full-span model data, and effect of surface roughness are provided.
Date: June 26, 1952
Creator: Shibata, Harry H.; Bandettini, Angelo & Cleary, Joseph
Item Type: Refine your search to only Report
open access

Investigation of thrust augmentation using water-alcohol injection on a 5200-pound-thrust axial-flow-type turbojet engine at static sea-level conditions

Description: Report presenting an investigation to evaluate the thrust augmentation available with various types of water-alcohol injection system on a 5200-pound-thrust axial-flow-type turbojet engine at sea-level, zero-ram conditions. Results regarding engine performance and operational characteristics are provided.
Date: September 4, 1952
Creator: Boman, David S. & Mallett, William E.
Item Type: Refine your search to only Report
open access

Investigation of Turbines for Driving Supersonic Compressors: 1: Design and Performance of First Configuration

Description: Report presenting the design and performance of a turbine to drive a supersonic compressor in order to determine the problems that would be encountered in turbines required to drive high-speed, high-weight-flow compressors. A model of the turbine was built and operated over a range of speed and total-pressure ratios. Results regarding performance, the effects of rotor choking, and possible modifications to the design are provided.
Date: June 17, 1952
Creator: Stewart, Warner L.; Schum, Harold J. & Whitney, Warren J.
Item Type: Refine your search to only Report
open access

Investigation of Turbines for Driving Supersonic Compressors 2: Performance of First Configuration With 2.2 Percent Reduction in Nozzle Flow Area

Description: "The experimental performance of a modified turbine for driving a supersonic compressor is presented and compared with the performance of the original configuration to illustrate the effect of small changes in the ratio of nozzle-throat area to rotor-throat area. Performance is based on the performance of turbines designed to operate with both blade rows close to choking. On the basis of the results of this investigation, the ratio of areas is concluded to become especially critical in the desi… more
Date: July 22, 1952
Creator: Stewart, Warner L.; Schum, Harold J. & Wong, Robert Y.
Item Type: Refine your search to only Report
open access

Investigation of turbines suitable for use in a turbojet engine with high compressor pressure ratio and low compressor-tip speed 1: turbine-design requirements for several engine operating conditions

Description: In order to insure satisfactory turbine performance under five turbojet-engine operating conditions, turbine design requirements were determined for the following operating conditions: take-off, maximum thrust at altitude, altitude cruising at rated rotative speed, altitude cruising with maximum-thrust exhaust nozzle area, and engine acceleration at 80 percent equivalent design rotative speed. If cruising is to be at rated engine speed, both cruising and take-off should be considered in turbine… more
Date: March 4, 1952
Creator: English, Robert E.; Silvern, David H. & Davison, Elmer H.
Item Type: Refine your search to only Report
open access

Investigation of turbines suitable for use in a turbojet engine with high compressor pressure ratio and low compressor tip-speed 2: velocity-diagram study of turbine for engine operation with constant exhaust-nozzle area

Description: Report presenting an investigation of whether or not a two-stage turbine with the frontal area no larger than the compressor frontal area could be satisfactorily designed to drive a particular compressor under take-off conditions. The low blade-tip speed, high work, and high air flow per unit of frontal area of the compressor make it critical that a two-stage turbine is designed to drive it. Results regarding the effect of work division, effect of variation in cone angle, and effects of radial … more
Date: June 19, 1952
Creator: Davison, Elmer H. & English, Robert E.
Item Type: Refine your search to only Report
open access

Investigation of turbines suitable for use in a turbojet engine with high compressor pressure ratio and low compressor-tip speed 3: velocity-diagram study of two-stage and downstream-stator turbines for engine operation at constant rotative speed

Description: Report presenting the use of a simplified method of analysis in order to relate the turbine operations for take-off and cruise at rotative speed. This allows turbine velocity diagrams to consider both take-off and cruising operation. Results regarding the two-stage turbine design and the downstream-stator turbine design are provided.
Date: November 21, 1952
Creator: English, Robert E. & Davison, Elmer H.
Item Type: Refine your search to only Report
open access

Investigation of turbines suitable for use in a turbojet engine with high compressor pressure ratio and low compressor-tip speed 4: effect of increasing blade speed on velocity diagrams of turbine for engine operation at constant rotative speed

Description: Report presenting the use of a simplified method of analysis in order to estimate the turbine blade-tip speed required to design satisfactory two-stage turbines. The investigation allows for certain conditions for optimal two-stage turbine design to be determined.
Date: November 24, 1952
Creator: Davison, Elmer H. & English, Robert E.
Item Type: Refine your search to only Report
open access

Investigation of vanes immersed in the jet of a solid-fuel rocket motor

Description: Report presenting a determination of the characteristics of a particular vane configuration in the jet of a 6.25-inch Deacon solid-fuel rocket motor from static testing. The vanes were oscillated during the test to provide comprehensive data over a range of deflection angles. The effects of the rocket jet on two vane materials, the aerodynamic characteristics of the vanes, and the influence of jet vanes on rocket-motor performance were determined.
Date: September 10, 1952
Creator: Giladett, Leo V. & Wineman, Andrew R.
Item Type: Refine your search to only Report
open access

An Investigation Utilizing an Electrical Analogue of Cyclic Deicing of a Hollow Steel Propeller with an External Blade Shoe

Description: "A study has been made of the heat requirement for the cyclic de-icing of hollow steel propellers fitted with external blade heating shoes. Solutions to the equations for the heat flow in cyclic heating of propellers were obtained, using an electrical analogy. The study showed how the energy requirement for propeller de-icing with existing blade shoes could be decreased, and illustrated the effect of blade-shoe design on the energy requirement. It was demonstrated, for example, that by increas… more
Date: December 1952
Creator: Neel, Carr B., Jr.
Item Type: Refine your search to only Report
open access

Investigation with an interferometer of the flow around a circular-arc airfoil at mach numbers between 0.6 and 0.9

Description: From Summary: "The flow around a 12-percent-thick circular-arc airfoil at zero incidence was observed with an interferometer for small increments of free-stream Mach number from 0.609 to 0.896 with laminar and turbulent boundary layers. Mach number contours in the flow field and Mach number and pressure distributions on the airfoil were obtained. Conditions were determined along and at the bases of the shock waves that interacted with the turbulent boundary layer on the airfoil."
Date: October 1952
Creator: Wood, George P. & Gooderum, Paul B.
Item Type: Refine your search to only Report
open access

Investigational Drilling, Hoskinnini Mesa

Description: From to the files: To date, all the mineralization seen in the Monument Valley area in the Shinarump formation has been in scour channels. The mineralized rock occurs at or near the bottom of the channel. On Hoskinnini Mesa, all the channels examined to date contain some mineralized material. Channels observed may in some cases contain copper without apparent uranium mineralization; others definitely exhibit copper-uranium mineralization.
Date: May 15, 1952
Creator: Chester, John W. & Pitman, R. K.
Item Type: Refine your search to only Report
open access

Investigations in the Fall Creek Area, Bonneville County, Idaho, During the 1952 Field Season: A Preliminary Report

Description: Introduction: Field work during the 1952 field season has supplied new data on the areal extent, composition, and estimated reserves of uranium-bearing carbonaceous rocks in the Fall Creek.area, Bonneville County, Idaho. The following is a preliminary report of progress to describe these new data which supplement the information contained in Trace Elements Memorandum Report 340 (Vine and Moore, 1952). This work was done on behalf of the Division of Raw Materials of the U. S. Atomic Energy Commi… more
Date: November 1952
Creator: Vine, James David
Item Type: Refine your search to only Report
open access

Investigations of Air-Cooled Turbine Rotors for Turbojet Engines 1: Experimental Disk Temperature Distribution in Modified J33 Split-Disk Rotor at Speeds up to 6000 RPM

Description: "An experimental investigation is being conducted at the Lewis laboratory to establish general principles for the design of noncritical turbine rotor configurations. This investigation includes evaluation of cooling effectiveness, structural stability, cooling-air flow distribution characteristics, and methods of supplying cooling air to the turbine rotor blades. Prior to design of a noncritical rotor, a standard turbine rotor of a commerical turbojet engine was split in the plane of rotation a… more
Date: January 9, 1952
Creator: Schramm, Wilson B. & Ziemer, Robert R.
Item Type: Refine your search to only Report
open access

Investigations of air-cooled turbine rotors for turbojet engines 2: mechanical design, stress analysis, and burst test of modified J33 split-disk rotor

Description: A full-scale J33 air-cooled split turbine rotor was designed and spin-pit tested to destruction. Stress analysis and spin-pit results indicated that the rotor in a J33 turbojet engine, however, showed that the rear disk of the rotor operated at temperatures substantially higher than the forward disk. An extension of the stress analysis to include the temperature difference between the two disks indicated that engine modifications are required to permit operation of the two disks at more nearly … more
Date: January 14, 1952
Creator: Kemp, Richard H. & Moseson, Merland L.
Item Type: Refine your search to only Report
Back to Top of Screen