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Biological Survey of Texas

Description: From introduction: "Report on the biological survey of Texas conducted over a number of years through collection of information and specimens. Focus on life zones and their subdivisions and on the mammals and reptiles of the state."
Date: October 24, 1905
Creator: Bailey, Vernon
Partner: UNT Libraries Government Documents Department
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Revision of the Skunks of the Genus Spilogale

Description: From introduction: "Revision of skunk genus Spilogale based upon a study of about 380 skins with skulls and 75 additional skulls from the collection of the Biological Survey."
Date: November 24, 1906
Creator: Howell, Arthur H.
Partner: UNT Libraries Government Documents Department
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The Gaseous Explosive Reaction: The Effect of Inert Gases

Description: "Attention is called in this report to previous investigations of gaseous explosive reactions carried out under constant volume conditions, where the effect of inert gases on the thermodynamic equilibrium was determined. The advantage of constant pressure methods over those of constant volume as applied to studies of the gaseous explosive reaction is pointed out and the possibility of realizing for this purpose a constant pressure bomb mentioned" (p. 479).
Date: June 24, 1927
Creator: Stevens, F. W.
Partner: UNT Libraries Government Documents Department
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Tests of large airfoils in the propeller research tunnel, including two with corrugated surfaces

Description: This report gives the results of the tests of seven 2 by 12 foot airfoils (Clark Y, smooth and corrugated, Gottingen 398, N.A.C.A. M-6, and N.A.C.A. 84). The tests were made in the propeller research tunnel of the National Advisory Committee for Aeronautics at Reynolds numbers up to 2,000,000. The Clark Y airfoil was tested with three degrees of surface smoothness. Corrugating the surface causes a flattening of the lift curve at the burble point and an increase in drag at small flying angles.
Date: May 24, 1929
Creator: Wood, Donald H.
Partner: UNT Libraries Government Documents Department
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Penetration and Duration of Fuel Sprays From a Pump Injection System

Description: "High-speed motion pictures were taken of individual fuel sprays from a pump injection system. The changes in the spray-tip penetration with changes in the pump speed, injection-valve opening and closing pressures, discharge-orifice area, injection-tube length and diameter, and pump throttle setting were measured. The pump was used with and without a check valve" (p. 241).
Date: August 24, 1931
Creator: Rothrock, A. M. & Marsh, E. T.
Partner: UNT Libraries Government Documents Department
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The Effect of Humidity on Engine Power at Altitude

Description: "From tests made in the altitude chamber of the Bureau of Standards, it was found that the effect of humidity on engine power is the same at altitudes up to 25,000 feet as at sea level. Earlier tests on automotive engines, made under sea-level conditions, showed that water vapor acts as an inert diluent, reducing engine power in proportion to the amount of vapor present. By combining the effects of atmospheric pressure, temperature, and humidity, it is shown that the indicated power obtainable … more
Date: February 24, 1932
Creator: Brooks, D. B. & Garlock, E. A.
Partner: UNT Libraries Government Documents Department
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A comparison between the theoretical and measured longitudinal stability characteristics of an airplane

Description: This report covers an investigation of the application of the theory of dynamic longitudinal stability, based on the assumption of small oscillations, to oscillations an airplane is likely to undergo in flight. The investigation was conducted with a small parasol monoplane for the fixed-stick condition. The period and damping of longitudinal oscillations were determined by direct measurements of oscillations in flight and also by calculation in which the factors that enter the theoretical stabi… more
Date: June 24, 1932
Creator: Soulé, Hartley A. & Wheatley, John B.
Partner: UNT Libraries Government Documents Department
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Wing Characteristics as Affected by Protuberances of Short Span

Description: "The drag and interference caused by short-span protuberances from the surface of an airfoil have been investigated in the NACA variable-density wind tunnel at a Reynolds number of approximately 3,100,000, based on the chord length of the airfoil. The effects of variations of protuberance span length, span position, and shape were measured by determining how the wing characteristics were affected by the addition of the various protuberances" (p. 155).
Date: October 24, 1932
Creator: Jacobs, Eastman N. & Sherman, Albert
Partner: UNT Libraries Government Documents Department
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Pressure Distribution Over Airfoils With Fowler Flaps

Description: Report presents the results of tests made of a Clark y airfoil with a Clark y Fowler flap and of an NACA 23012 airfoil with NACA Fowler flaps. Some of the tests were made in the 7 by 10-foot wind tunnel and others in the 5-foot vertical wind tunnel. The pressures were measured on the upper and lower surfaces at one chord section both on the main airfoils and on the flaps for several angles of attack with the flaps located at the maximum-lift settings.
Date: November 24, 1937
Creator: Wenzinger, Carl J. & Anderson, Walter B.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of NACA 23012 airfoil with various arrangements of slotted flaps

Description: "An investigation was made in the NACA 7 by 10-foot wind tunnel of a large-chord NACA 23012 airfoil with several arrangements of 25.66 percent chord slotted flaps to determine the section aerodynamic characteristics as affected by slot shape, flap shape, flap location, and flap deflection. The flap position for maximum lift, the polars for arrangements considered favorable for take-off and climb, and the complete section aerodynamic characteristics for selected optimum arrangements were determi… more
Date: February 24, 1939
Creator: Wenzinger, Carl J. & Harris, Thomas A.
Partner: UNT Libraries Government Documents Department
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A Theoretical Study of the Moment on a Body in a Compressible Fluid

Description: "The extension to a compressible fluid of Lagally's theorem on the moment on a body in an incompressible fluid and Poggi's method of treating the flow of compressible fluids are employed for the determination of the effect of compressibility on the moment of an arbitrary body. Only the case of the two-dimensional subsonic flow of an ideal compressible fluid is considered. As examples of the application of the general theory, two well-known systems of profiles are treated; namely the elliptic pr… more
Date: March 24, 1939
Creator: Kaplan, Carl
Partner: UNT Libraries Government Documents Department
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Experimental Verification of the Theory of Oscillating Airfoils

Description: "Measurements have been made of the lift on an airfoil in pitching oscillation with a continuous-recording, instantaneous-force balance. The experimental values for the phase difference between the angle of attack and the lift are shown to be in close agreement with theory" (p. 619).
Date: April 24, 1939
Creator: Silverstein, Abe & Joyner, Upshur T.
Partner: UNT Libraries Government Documents Department
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Longitudinal Stability and Control With Special Reference to Slipstream Effects

Description: Report presents the results of a study of data obtained in the NACA full-scale wind tunnel concerning the effects of interference and of propeller operation on longitudinal stability and control. The data include pitching moments for various power conditions for airplanes with tails removed and with tails set at various stabilizer and elevator angles. A number of surveys of the dynamic pressure and the flow direction in the region of the horizontal tail surface are also included.
Date: August 24, 1939
Creator: Katzoff, S.
Partner: UNT Libraries Government Documents Department
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A high-speed motion-picture study of normal combustion, knock and preignition in a spark-ignition engines

Description: Combustion in a spark-ignition engine was investigated by means of the NACA high-speed motion-picture cameras. This camera is operated at a speed of 40,000 photographs a second and therefore makes possible the study of changes that take place in the intervals as short as 0.000025 second. When the motion pictures are projected at the normal speed of 16 frames a second, any rate of movement shown is slowed down 2500 times. Photographs are presented of normal combustion, of combustion from preigni… more
Date: July 24, 1940
Creator: Rothrock, A. M.; Spencer, R. C. & Miller, Cearcy D.
Partner: UNT Libraries Government Documents Department
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An apparatus for measuring rates of discharge of a fuel-injection system

Description: From Introduction: "An apparatus that gives a quick and an accurate measurement of the rate of discharge has been has been designed by the NACA and is described in this report."
Date: March 24, 1941
Creator: Dutee, Francis J.
Partner: UNT Libraries Government Documents Department
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Requirements for Satisfactory Flying Qualities of Airplanes

Description: Report discusses the results of an analysis of available data to determine what measured characteristics are significant in defining satisfactory flying qualities, what characteristics are reasonable to require of an airplane, and what influence the various design features have on the observed flying qualities.
Date: March 24, 1941
Creator: Gilruth, R. R.
Partner: UNT Libraries Government Documents Department
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Square Plate With Clamped Edges Under Normal Pressure Producing Large Deflections

Description: "A theoretical analysis is given for the stresses and deflections of a square plate with clamped edges under normal pressure producing large deflections. Values of the bending stress and membrane stress at the center of the plate and at the midpoint of the edge are given for center deflections up to 1.9 times the plate thickness. The shape of the deflected surface is given for low pressures and for the highest pressure considered" (p. 209).
Date: May 24, 1941
Creator: Levy, Samuel
Partner: UNT Libraries Government Documents Department
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Low-Density UO2 Pile

Description: The multiplication factor and minimum pile size for a multiplying pile using UO2 powder of density 1 have been computed. It appears that a k of 1.0177 is possible for a volume ration of V/V001=3.33.
Date: February 24, 1943
Creator: Ibser, H. W.
Partner: UNT Libraries Government Documents Department
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The Resonance Absorption Spectrum of Uranium

Description: A model for the capture spectrum of uranium is introduced in which levels occur at 7, 30, 30+D, 30+2D, ..., ev. Gamma ray and neutron widths are derived from the experimental data for values of D between 10 and 25 ev. The constants of the 7 volt level prove to be independent of D. Extrapolation, using the one level formula, gives a capture cross section at (1/40) ev of 4.9 x 10(24) cm2; this number is, however, quite sensitive to the value taken for the resonance activation. Both neutron and ga… more
Date: November 24, 1943
Creator: Dancoff, Sidney M., 1913-1951
Partner: UNT Libraries Government Documents Department
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Solid residue

Description: This document is a letter written February 24, 1944, concerning solids found when evaporating water from the Columbia River.
Date: February 24, 1944
Creator: Greenewalt, C. H.
Partner: UNT Libraries Government Documents Department
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Experiments on Drag of Revolving Disks, Cylinders, and Streamline Rods at High Speeds

Description: An experimental investigation concerned primarily with the extension of test data on the drag of revolving disks, cylinders, and streamline rods to high Mach numbers and Reynolds numbers is presented. A Mach number of 2.7 was reached for revolving rods with Freon 113 as the medium. The tests on disks extended to a Reynolds number of 7,000,000" (p. 367).
Date: April 24, 1944
Creator: Theodorsen, Theodore & Regier, Arthur
Partner: UNT Libraries Government Documents Department
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Application of Spring Tabs to Elevator Controls

Description: Equations are presented for calculating the stick-force characteristics obtained with a spring-tab type of elevator control. The main problems encountered in the design of a satisfactory elevator spring tab are to provide stick forces in the desired range, to maintain the force per g sufficiently constant throughout the speed range, to avoid undesirable "feel" of the control in ground handling or in flight at low airspeeds, and to prevent flutter. Examples are presented to show the design featu… more
Date: November 24, 1944
Creator: Phillips, William H.
Partner: UNT Libraries Government Documents Department
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C-616 UF$sub 6$ HYDROLYSIS FUMES

Description: Experiments were carried out to determine how fast the concentration of suspended material decreases in fumes produced by the hydrolysis of UF/sub 6/ vapor in damp air. The rate of aggregation is a function chiefly of the number of particles per unit gas volume, but depends also on the chemical composition, size and shape of the particles, the temperature and pressure, and the degree of agitation. The rate of settling depends on the weight and shape of the particles and the viscosity of the gas… more
Date: January 24, 1945
Creator: Fisher, M. & Cines, M.R.
Partner: UNT Libraries Government Documents Department
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Chemical Research -- Extraction and Properties of U233; Report for the Period Ending December 15, 1944

Description: Technical report containing short articles on (1) Determination of physical constants for U233; (2) Determination of decay chain of U233; (3) Extraction of U233; (4) Extracting solvents for uranium; (5) Factors affecting the extraction uranium and thorium by organic solvents, especially ether; and (6) Analysis of ore samples for protoactinium.
Date: February 24, 1945
Creator: Seaborg, Glenn T. (Glenn Theodore), 1912-1999; Manning, F. M. & Katzin, L. I.
Partner: UNT Libraries Government Documents Department
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