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Revision of the North American Bats of the Family Vespertilionidæ
Classification of more than 3,000 bats to enable correct specimen identification based upon material contained in the collection of the Biological Survey of the U.S. Department of Agriculture.
Date:
October 16, 1897
Creator:
Miller, Gerrit S. (Gerrit Smith), 1869-1956
Object Type:
Report
System:
The UNT Digital Library
Tables of Thermodynamic Properties of Ammonia
A report containing tables of thermodynamic properties of ammonia.
Date:
April 16, 1923
Creator:
unknown
Object Type:
Report
System:
The UNT Digital Library
Investigation of damping liquids for aircraft instruments
"This report covers the results of an investigation carried on at the Bureau of Standards under a research authorization from, and with the financial assistance of, the National Advisory Committee for Aeronautics. The choice of a damping liquid for aircraft instruments is difficult owing to the range of temperature at which aircraft operate. Temperature changes affect the viscosity tremendously. The investigation was undertaken with the object of finding liquids of various viscosities otherwise suitable which had a minimum change in viscosity with temperature" (p. 405).
Date:
May 16, 1928
Creator:
Keulegan, G. H.
Object Type:
Report
System:
The UNT Digital Library
Experimental determination of jet boundary corrections for airfoil tests in four open wind tunnel jets of different shapes
"This experimental investigation was conducted primarily for the purpose of obtaining a method of correcting to free air conditions the results of airfoil force tests in four open wind tunnel jets of different shapes. Tests were also made to determine whether the jet boundaries had any appreciable effect on the pitching moments of a complete airplane model. Satisfactory corrections for the effect of the boundaries of the various jets were obtained for all the airfoils tested, the span of the largest being 0.75 of the jet width" (p. 609).
Date:
April 16, 1930
Creator:
Knight, Montgomery & Harris, Thomas A.
Object Type:
Report
System:
The UNT Digital Library
A method for computing leading-edge loads
From Summary: "In this report a formula is developed that enables the determination of the proper design load for the portion of the wing forward of the front spar. The formula is inherently rational in concept, as it takes into account the most important variables that affect the leading-edge load, although theoretical rigor has been sacrificed for simplicity and ease of application. Some empirical corrections, based on pressure distribution measurements on the PW-9 and M-3 airplanes have been introduced to provide properly for biplanes. Results from the formula check experimental values in a variety of cases with good accuracy in the critical loading conditions. The use of the method for design purposes is therefore felt to be justified and is recommended."
Date:
January 16, 1931
Creator:
Rhode, Richard V. & Pearson, Henry A.
Object Type:
Report
System:
The UNT Digital Library
The effect of area aspect ratio on the yawing moments of rudders at large angles of pitch on three fuselages
This reports presents the results of measurements made of yawing moments produced by rudder displacement for seven rudders mounted on each of three fuselages at angles of pitch of 0 degree, 8 degrees, 12 degrees, 20 degrees, 30 degrees and 40 degrees. The dimensions of the rudders were selected to cover the range of areas and aspect ratios commonly used, while the ratios of rudder area to fin area and of rudder chord to fin chord were kept approximately constant. An important result of the measurements is to show that increased aspect ratio gives increased yawing moments for a given area, provided the maximum rudder displacement does not exceed 25 degrees. If large rudder displacements are used, the effect of aspect ratio is not so great.
Date:
May 16, 1932
Creator:
Dryden, Hugh L. & Monish, B. H.
Object Type:
Report
System:
The UNT Digital Library
Spinning characteristics of the XN2Y-1 airplane obtained from the spinning balance and compared with results from the spinning tunnel and from flight tests
Report presents the results of tests of a 1/10-scale model of the XN2Y-1 airplane tested in the NACA 5-foot vertical wind tunnel in which the six components of forces and moments were measured. The model was tested in 17 attitudes in which the full-scale airplane had been observed to spin, in order to determine the effects of scale, tunnel, and interference. In addition, a series of tests was made to cover the range of angles of attack, angles of sideslip, rates of rotation, and control setting likely to be encountered by a spinning airplane. The data were used to estimate the probable attitudes in steady spins of an airplane in flight and of a model in the free-spinning tunnel. The estimated attitudes of steady spin were compared with attitudes measured in flight and in the spinning tunnel. The results indicate that corrections for certain scale and tunnel effects are necessary to estimate full-scale spinning attitudes from model results.
Date:
April 16, 1937
Creator:
Bamber, M. J. & House, R. O.
Object Type:
Report
System:
The UNT Digital Library
The application of basic data on planing surfaces to the design of flying-boat hulls
From Introduction: "This report is concerned with the presentation of planning data in a form that facilities direct application to the initial stage of design."
Date:
December 16, 1939
Creator:
Diehl, Walter S.
Object Type:
Report
System:
The UNT Digital Library
Preignition characteristics of several fuels under simulated engine conditions
"The preignition characteristics of a number of fuels have been studied under conditions similar to those encountered in an engine. These conditions were simulated by suddenly compressing a fuel-air mixture in contact with an electrically heated hot spot in the cylinder head of the NACA combustion apparatus. Schlieren photographs and indicator cards were taken of the burning, and the hot-spot temperatures necessary to cause ignition under various conditions were determined" (p. 121).
Date:
September 16, 1940
Creator:
Spencer, R. C.
Object Type:
Report
System:
The UNT Digital Library
Nonstationary flow about a wing-aileron-tab combination including aerodynamic balance
This paper presents a continuation of the work published in Technical Report no. 496. The results of that paper have been extended to include the effect of aerodynamic balance and the effect of a tab added to the aileron. The aerodynamic coefficients are presented in a form convenient for application to the flutter problem.
Date:
December 16, 1941
Creator:
Theodorsen, Theodore & Garrick, I. E.
Object Type:
Report
System:
The UNT Digital Library
A Method for Determining the Camber and Twist of a Surface to Support a Given Distribution of Lift, With Applications to the Load Over a Sweptback Wing
"A graphical method is described for finding the shape (camber and twist) of an airfoil having an arbitrary distribution of lift. The method consists in replacing the lifting surface and its wake with an equivalent arrangement of vortices and in finding the associated vertical velocities. By division of the vortex pattern into circular strips concentric about the downwash point instead of into the usual rectangular strips, the lifting surface is reduced for each downwash point to an equivalent loaded line for which the induced velocity is readily computed" (p. 543).
Date:
May 16, 1942
Creator:
Cohen, Doris
Object Type:
Report
System:
The UNT Digital Library
The mean aerodynamic chord and the aerodynamic center of a tapered wing
A preliminary study of pitching-moment data on tapered wings indicated that excellent agreement with test data was obtained by locating the quarter-chord point of the average chord on the average quarter-chord point of the semispan. The study was therefore extended to include most of the available data on tapered-wing models tested by the NACA.
Date:
June 16, 1942
Creator:
Diehl, Walter S.
Object Type:
Report
System:
The UNT Digital Library
On the Multiplication Constant of Homogeneous Mixtures of U with Various Moderators
The following represents a summary of calculations on the multiplication constant of homogeneous mixtures of uranium and different moderators. These calculations were made possible by Fermi's determination of the age of neutrons and by the extrapolation to higher scattering cross-sections of the resonance absorption of uranium as measured by C. Creutz. According to Fermi, the former quantity is 120 sq. cm. The latter is given in the two attached graphs. The first (Fig.1) of these goes as high as a scattering cross-section of 70 x 10-24 cm.2 per uranium atom, and its highest point is taken from a measurement of Cruetz's in which a mixture of U3O8 and graphite was used.
Date:
May 16, 1943
Creator:
Wigner, Eugene Paul, 1902-1995 & Stephenson, J.
Object Type:
Report
System:
The UNT Digital Library
Requirements for Auxiliary Stiffeners Attached to Panels Under Combined Compression and Shear
"Panels of aluminum alloy sheets, framed by side and end stiffeners, were subjected to combined loading by means of offset knife edges applying loads to top and bottom end plates with reacting forces against the end plates supplied by laterally acting rollers. The test specimens were 17S-T aluminum alloy shoots 0.040 inch thick in panels of 10-inch width and three different lengths (approximately 10, 26, and 30 inch). Data were obtained for the bowing of transverse and longitudinal ribs of rectangular cross section and varying depths mounted on one side of the sheet only, for several ratios of compression to shear loads" (p. 1).
Date:
September 16, 1943
Creator:
Scott, Merit & Weber, Robert L.
Object Type:
Report
System:
The UNT Digital Library
Metallurgical Laboratory, Chemical Research - Radiation Chemistry, Errara for CC-918
Technical report listing the errata for pages 2, 4, 5, 6, 7, and 8 for report CC-918.
Date:
October 16, 1943
Creator:
Franck, J.
Object Type:
Report
System:
The UNT Digital Library
Metallurgical Laboratory, Chemical Research - Heavy Water, Report for the Month Ending May 1, 1944
Technical report with short reports on (1) Heavy water analysis and standardization, and Specific gravity of pure D2O; (2) Homogenous exponential experiment; (3) Recombination of pile gases; (4) Slurry pumping studies; and (5) Electron microscope laboratory.
Date:
May 16, 1944
Creator:
Hogness, T. R. (Thorfin Rusten), 1894-; Hiskey, C. F. & Eidinoff, Maxwell Leigh, 1915-
Object Type:
Report
System:
The UNT Digital Library
Preparation of U233
Technical report. The object of the research is to determine the procedure and equipment for the preparation of U233 on a semi-works scale. The general proposed procedure is that thorium carbonate in aluminum cans will be irradiated with pile neutrons. The Pa233 resulting from neutron absorption the Th232 and the decay of Th233 will be extraction from 99% of the thorium and the natural U in thorium by MnO2 precipitations. The Pa233 will then be allowed to decay to U233 which in turn will be isolated from the remaining Th and partially decayed Pa233 by ether extraction.
Date:
May 16, 1944
Creator:
Apple, R. S.
Object Type:
Report
System:
The UNT Digital Library
Further End Cap Temperature Calculations
Abstract. Recently (CP-1989) it has been shown that the neutron density, and thus the heat production, at the end of a slug with an A1 cap may be appreciably higher than that at the middle of the slag. A re-examination of earlier temperature calculations is made in light of this effect.
Date:
August 16, 1944
Creator:
Karush, William; Monk, A. T. & Wilkins, J. Ernest, Jr., 1923-2011
Object Type:
Report
System:
The UNT Digital Library
Detail Calculations of the Estimated Shift in Stick-Fixed Neutral Point Due to the Windmilling Propeller and to the Fuselage of the Republic XF-12 Airplane
"Detail calculations are presented of the shifts in stick-fixed neutral point of the Republic XF-12 airplane due to the windmilling propellers and to the fuselage. The results of these calculations differ somewhat from those previously made for this airplane by Republic Aviation Corporation personnel under the direction of Langley flight division personnel. Due to these differences the neutral point for the airplane is predicted to be 37.8 percent mean aerodynamic chord, instead of 40.8 percent mean aerodynamic chord as previously reported" (p. 1).
Date:
October 16, 1944
Creator:
White, M. D.
Object Type:
Report
System:
The UNT Digital Library
The Determination of T at the Dropping Mercury Electrode in Hex Plant Ammonia and Peroxide Decantrates
Inroduction: "A study of the literature, particularly the work done by R. Strubl, I.W. Kolthoff and S.B. Smith, indicated that a polargraphic method for the estimation of T could be devised which would not sacrifice reasonable accuracy for rapidity. Work was begun with the intention of developing such a method."
Date:
January 16, 1945
Creator:
Kwiatkowski, S.; Owens, J. & Casto, C. C.
Object Type:
Report
System:
The UNT Digital Library
Complexing Agents for the Solvent Extraction of Uranium from Thorium. I. The Use of Thiocyanate in the Extraction of Uranium. II. The Use of Antipyrine in Solvent Extraction
Abstract. In the first section of this technical report a new method of extracting uranium from thorium nitrate solution is discussed. This method consists of extracting an aqueous solution of thorium nitrate, nitric acid, sodium sulphate, and potassium thiocyanate with hexone. By this procedure, using an equal volume of hexone it is possible to extract 83 percent of the uranium while only 0.3 percent of the thorium is extracted. other experiments show that even greater separations are possible. In the second section of this report the use of antipyrine in solvent extraction procedures is discussed. Experiments are described in which 90 percent of the uranium is extracted while the thorium is extracted to the order of 3 to 5 percent.
Date:
February 16, 1945
Creator:
Reas, W. H.
Object Type:
Report
System:
The UNT Digital Library
A Rapid Method for Determination of Water in TO₃
Summary: A set of conditions is described for a ten minute determination of water in TO₃ by ignition and absorption of the evolved water in magnesium perchlorate. Complete conversion to T₃O₃ is obtained under these conditions, so that total loss on ignition and total T (plus non-volatile impurity) content may also be obtained. It has been found unnecessary to employ Cu foil to prevent interference by nitrates, which may be present with a nitrate/water ratio as high as 5, and in an amount that does not exceed 100 mg.
Date:
February 16, 1945
Creator:
Barash, Bernard B.; Lee, Franklin B. & Curtiss, Edgar O.
Object Type:
Report
System:
The UNT Digital Library
Tests of an Adjustable-Area Exhaust Nozzle for Jet-Propulsion Engines
Report discussing a comparison between a centrifugal-flow-type turbojet engine with an adjustable-area exhaust nozzle and with a series of fixed-area nozzles of various throat diameters. The adjustable-area nozzle was found to be as efficient as the fixed-area nozzles in testing. Information about the corrected static thrust, fuel flow, and tail-pipe gas temperature for both types of nozzles is provided.
Date:
August 16, 1945
Creator:
Wilcox, E. C.
Object Type:
Report
System:
The UNT Digital Library
NACA Investigation of Fuels Corresponding to Specification an-F-58 : Results of Studies in Single Combustors of J-33, J-34, J-35, and Nene Turbojet Engines
"The NACA is engaged in a program to evaluate the performance of fuels conforming to AN-F-58 specification in both full-scale engines and single combustors. This research memorandum constitutes an interim report on the results obtained on single cosibustors" (p. 1).
Date:
November 16, 1945
Creator:
Cleveland Laboratory Staff
Object Type:
Report
System:
The UNT Digital Library