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Revision of the North American Pocket Mice

Description: From introductory remarks: "Classification study of the North American pocket mouse based on about 170 specimens. Results of study increased recognized species to 18 and subspecies to 3 as well as shifting several well known names to other forms."
Date: October 25, 1889
Creator: Merriam, C. Hart
Partner: UNT Libraries Government Documents Department
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Electrolysis and its Mitigation

Description: Technical paper issued by the Bureau of Standards over studies conducted on electrolysis. As stated in the introduction, "this investigation has included a study of the physical laws governing electrolytic and self-corrosion in soils, an extended investigation of the effects of electric currents on plain and reinforced concrete, and a study of the work of previous investigators relating to the subject of electrolysis and its prevention" (p. 5). This paper includes tables, illustrations, and photographs.
Date: November 25, 1918
Creator: Rosa, Edward B. & McCollum, Burton
Partner: UNT Libraries Government Documents Department
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Comparison of Alcogas Aviation Fuel With Export Aviation Gasoline

Description: Mixtures of gasoline and alcohol when used in internal combustion engines designed for gasoline have been found to possess the advantage of alcohol in withstanding high compression without "knock" while retaining advantages of gasoline with regard to starting characteristics. Test of such fuels for maximum power-producing ability and fuel economy at various rates of consumption are thus of practical importance, with especial reference to high-compression engine development. This report discusses the results of tests which compares the performance of alcogas with x gasoline (export grade) as a standard.
Date: November 25, 1919
Creator: Gage, V. R.; Sparrow, S. W. & Harper, D. R.
Partner: UNT Libraries Government Documents Department
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Endurance Tests of Tires

Description: Technical paper issued by the Bureau of Standards over studies conducted on the endurance of tires. 230 tires of 36 different brands were tested during the studies. The results of the studies are presented and discussed. This paper includes tables, and photographs.
Date: May 25, 1926
Creator: Holt, W. L. & Wormeley, P. L.
Partner: UNT Libraries Government Documents Department
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The relative performance obtained with several methods of control of an overcompressed engine using gasoline

Description: "This report presents some results obtained during an investigation to determine the relative characteristics for several methods of control of an overcompressed engine using gasoline and operating under sea-level conditions. For this work, a special single cylinder test engine, 5-inch bore by 7-inch stroke, and designed for ready adjustment of compression ratio, valve timing and valve lift while running, was used. This engine has been fully described in NACA-TR-250. Tests were made at an engine speed of 1,400 R. P. M. for compression ratios ranging from 4.0 to 7.6" (p. 329).
Date: February 25, 1927
Creator: Gardiner, Arthur W. & Whedon, William E.
Partner: UNT Libraries Government Documents Department
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The N.A.C.A. photographic apparatus for studying fuel sprays from oil engine injection valves and test results from several researches

Description: "Apparatus for recording photographically the start, growth, and cut-off of oil sprays from injection valves has been developed at the Langley Memorial Aeronautical Laboratory. The apparatus consists of a high-tension transformer by means of which a bank of condensers is charged to a high voltage. The controlled discharge of these condensers in sequence, at a rate of several thousand per second, produces electric sparks of sufficient intensity to illuminate the moving spray for photographing. The sprays are injected from various types of valves into a chamber containing gases at pressures up to 600 pounds per square inch" (p. 361).
Date: May 25, 1927
Creator: Beardsley, Edward G.
Partner: UNT Libraries Government Documents Department
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The Gaseous Explosive Reaction: A Study of the Kinetics of Composite Fuels

Description: "This report deals with the results of a series of studies of the kinetics of gaseous explosive reactions where the fuel under observation, instead of being a simple gas, is a known mixture of simple gases. In the practical application of the gaseous explosive reaction as a source of power in the gas engine, the fuels employed are composite, with characteristics that are apt to be due to the characteristics of their components and hence may be somewhat complex" (p. 503).
Date: April 25, 1928
Creator: Stevens, F. W.
Partner: UNT Libraries Government Documents Department
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Working Charts for the Selection of Aluminum Alloy Propellers of a Standard Form to Operate With Various Aircraft Engines and Bodies

Description: "Working charts are given for the convenient selection of aluminum alloy propellers of a standard form, to operate in connection with six different engine-fuselage combinations. The charts have been prepared from full-scale test data obtained in the 20-foot propeller research tunnel of the National Advisory Committee for Aeronautics. An example is also given showing the use of the charts" (p. 3).
Date: March 25, 1929
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department
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Comparative flight performance with an NACA Roots supercharger and a turbocentrifugal supercharger

Description: This report presents the comparative flight results of a roots supercharger and a turbocentrifugal supercharger. The tests were conducted using a modified DH-4M2 airplane. The rate of climb and the high speed in level flight of the airplane were obtained for each supercharger from sea level to the ceiling. The unsupercharged performance with each supercharger mounted in place was also determined. The results of these tests show that the ceiling and rate of climb obtained were nearly the same for each supercharger, but that the high speed obtained with the turbocentrifugal was better than that obtained with the roots. The high-speed performance at 21,000 feet was 122 and 142 miles per hour for the roots and turbocentrifugal, respectively.
Date: February 25, 1930
Creator: Schey, Oscar W. & Young, Alfred W.
Partner: UNT Libraries Government Documents Department
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The effect on airplane performance of the factors that must be considered in applying low-drag cowling to radial engines

Description: From Summary: "This report presents the results of flight tests with three different airplanes using several types of low-drag cowling for radial air-cooled engines. The greater part of the tests were made with a Curtiss XF7Cc-1 (Sea Hawk) with a 410 horsepower. Wasp engine, using three fuselage nose shapes and six types of outer cowling. The six cowlings were: a narrow ring, a wide ring, a wide cowling similar in the original NACA cowling, a thick ring incorporating an exhaust collector, a single-surface cowling shaped like the outer surface of the exhaust-collector cowling, and polygon-ring cowling, of which the angle of the straight sections with the thrust line could be varied over a wide range."
Date: November 25, 1931
Creator: McAvoy, William H.; Schey, Oscar W. & Young, Alfred W.
Partner: UNT Libraries Government Documents Department
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Preliminary Investigation of Modifications to Conventional Airplanes to Give Nonstalling and Short-Landing Characteristics

Description: "This report describes flight and landing tests made on a group of conventional airplanes. The upward deflection of the elevators was limited to the point where the airplanes could not be made to spin without the aid of power. With the elevator travel thus limited, the airplane in every case had good lateral stability and good aileron effectiveness up to the highest angles of attack which could be obtained in a glide, although this was not true in any case without the limited control" (p. 343).
Date: January 25, 1932
Creator: Weick, Fred E.
Partner: UNT Libraries Government Documents Department
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Some Effects of Argon and Helium Upon Explosions of Carbon Monoxide and Oxygen

Description: Report presents the results of an investigation conducted to study the effects of the inert gases, argon and helium, upon flame speed and expansion ratio in exploding mixtures of carbon monoxide, oxygen and water. For the particular gas mixtures investigated the results show that: (1) With the possible exception of helium in small amounts the addition of inert gas always produces decreased flame speed and expansion ratio; (2) like volumes of argon and helium have very different effects upon flame speed but practically the same effect upon expansion ratio; and (3) the difference in the effect of these two gases upon speed is independent of the ratio of carbon monoxide to oxygen. A discussion of some possible modes by which inert gases may produce the observed effects is included.
Date: September 25, 1935
Creator: Fiock, Ernst F. & Roeder, Carl H.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of Ordinary and Split Flaps on Airfoils of Different Profile

Description: Report presents the results of wind tunnel tests of the Clark Y, the NACA 23012 and the NACA 23021 airfoils equipped with full-span ordinary flaps and with full-span simple split flaps. The principal object of the tests was to determine the characteristics of the airfoils with ordinary flaps and in addition, to determine the relative merits of the various airfoils when equipped with either ordinary flaps or with simple split flaps. The Clark Y airfoil was tested with 3 widths of ordinary flap, 10, 20, and 30 percent of the airfoil chord.
Date: October 25, 1935
Creator: Wenzinger, Carl J.
Partner: UNT Libraries Government Documents Department
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Calculated and measured pressure distributions over the midspan section of the NACA 4412 airfoil

Description: Pressures were simultaneously measured in the variable-density tunnel at 54 orifices distributed over the midspan section of 5 by 30 inch rectangular model of the NACA 4412 airfoil at 17 angles of attack ranging from -20 degrees to 30 degrees at a Reynolds number of approximately 3,000,000. Accurate data were thus obtained for studying the deviations of the results of potential-flow theory from measured results. The results of the analysis and a discussion of the experimental technique are presented.
Date: March 25, 1936
Creator: Pinkerton, Robert M.
Partner: UNT Libraries Government Documents Department
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Heat Transfer to Fuel Sprays Injected Into Heated Gases

Description: This report presents the results of a study made of the influence of several variables on the pressure decrease accompanying injection of a relatively cool liquid into a heated compressed gas. Indirectly, this pressure decrease and the time rate of change of it are indicative of the total heat transferred as well as the rate of heat transfer between the gas and the injected liquid. Air, nitrogen, and carbon dioxide were used as ambient gases; diesel fuel and benzene were the injected liquids. The gas densities and gas-fuel ratios covered approximately the range used in compression-ignition engines. The gas temperatures ranged from 150 degrees c. to 350 degrees c.
Date: August 25, 1936
Creator: Selden, Robert F. & Spencer, Robert C.
Partner: UNT Libraries Government Documents Department
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Fuel spray and flame formation in a compression-ignition engine employing air flow

Description: "The effects of air flow on fuel spray and flame formation in a high-speed compression-ignition engine have been investigated by means of the NACA combustion apparatus. The process was studied by examining high-speed motion pictures taken at the rate of 2,200 frames a second. The combustion chamber was of the flat-disk type used in previous experiments with this apparatus. The air flow was produced by a rectangular displacer mounted on top of the engine piston. Three fuel-injection nozzles were tested: a 0.020-inch single-orifice nozzle, a 6-orifice nozzle, and a slit nozzle" (p. 281).
Date: November 25, 1936
Creator: Rothrock, A. M. & Waldron, C. D.
Partner: UNT Libraries Government Documents Department
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Static Thrust and Power Characteristics of Six Full-Scale Propellers

Description: "Static thrust and power measurements were made of six full-scale propellers. The propellers were mounted in front of a liquid-cooled-engine nacelle and were tested at 15 different blade angles in the range from -7 1/2 degrees to 35 degrees at 0.75r. The test rig was located outdoors and the tests were made under conditions of approximately zero wind velocity" (p. 85).
Date: January 25, 1939
Creator: Hartman, Edwin P. & Biermann, David
Partner: UNT Libraries Government Documents Department
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Chemical Properties of Uranium Hexafluoride, UF6

Description: Uranium hexafluoride has the distinction of being the only stable gaseous compound of uranium known up to the present moment. Because of this property it is the only compound that can be used for processes of isotope separation, such as diffusion, thermal diffusion, centrifuge separation, distillation, and other of a similar nature. Here is a short description of the properties of UF{sub 6} and is intended for a reader interested only casually in this compound. UF{sub 6} is a very reactive compound and a very strong fluorinating agent. It is immediately hydrolized by water. In fluorinating reactions it is reduced to the green highly stable UF{sub 4}. It reacts instantaneously with hydrogen at room temperature. It fluorinates many metals; sodium and mercury are attacked in the cold, lead, zinc, tin and iron on heating; platinum and gold react only above 400 C. With organic compounds like alcohol, ether, benzene or toluene, immediate fluorination takes place with formation of HF and carbon or carbonaceous material. The compound forms colorless, very volatile, beautiful transparent crystals of high refractive index. Melting point = 69.5{sup o}; boiling point at 760 mm = 56.2{sup o}; D20{sup o} = 4.68. The crystals melt water pressure to a transparent colorless liquid of high density, but great mobility.
Date: June 25, 1941
Creator: Grosse, Aristid V.
Partner: UNT Libraries Government Documents Department
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Effect of Normal Pressure on the Critical Compressive Stress of Curved Sheet

Description: Results are presented of tests of two specimens tested to study the effect of normal pressure on the critical compressive stress for thin curved sheets. These specimens are designated by their respective rib spacings of 10 inches and 30 inches. The relationship between compressive stress and normal pressure at which buckles disappeared is independent of whether the buckles were made to disappear by increase of normal pressure or decrease of compressive stress. (author).
Date: August 25, 1942
Creator: Rafel, Norman
Partner: UNT Libraries Government Documents Department
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Temperature Rise in a Heat Producing Cylinder Under a Coating Defect

Description: Abstract: "For defects between interior and coating, or between successive layers of coating, a simple, fairly accurate formula is established. The temperature rise at the edge of the defect is briefly discussed."
Date: January 25, 1944
Creator: Ginsburg, M.; Karush, W. & Young, G.
Partner: UNT Libraries Government Documents Department
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Eta Temperature Effect

Description: The temperature coefficient of eta has been measured with the thermal column of the Argonne pile using uranium foils of different isotopic ratios. The temperature change was effected by filtering neutrons through silver. The measured fractional change per degree centigrade is [formula].
Date: February 25, 1944
Creator: Bragdon, E. W.; Hughes, D. & Marshall, John
Partner: UNT Libraries Government Documents Department
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Intercooler cooling-air weight flow and pressure drop for minimum drag loss

Description: An analysis has been made of the drag losses in airplane flight of cross-flow plate and tubular intercoolers to determine the cooling-air weight flow and pressure drop that give a minimum drag loss for any given cooling effectiveness and, thus, a maximum power-plant net gain due to charge-air cooling. The drag losses considered in this analysis are those due to (1) the extra drag imposed on the airplane by the weight of the intercooler, its duct, and its supports and (2) the drag sustained by the cooling air in flowing through the intercooler and its duct. The investigation covers a range of conditions of altitude, airspeed, lift-drag ratio, supercharger-pressure ratio, and supercharger adiabatic efficiency. The optimum values of cooling air pressure drop and weight flow ratio are tabulated. Curves are presented to illustrate the results of the analysis.
Date: February 25, 1944
Creator: Reuter, J. George & Valerino, Michael F.
Partner: UNT Libraries Government Documents Department
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