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Natural History of the Tres Marías Islands, Mexico

Description: Brief description of the Tres Marías Islands, Mexico, including mammals, birds, reptiles, crustacea, and plants found there.
Date: April 29, 1899
Creator: Nelson, E. W.; Stejneger, Leonhard; Rathbun, Mary J. & Rose, J. N.
Partner: UNT Libraries Government Documents Department

To Establish Glacier National Park in Montana, Report

Description: This report contains a recommendation by the Committee on Public Lands to pass Senate bill 5648 which proposes the creation of Glacier National Park in Montana. It includes letters of the Secretary of Interior and the Secretary of Agriculture in relation to the proposed bill, in addition to a map of the proposed boundaries and photographs of scenic landmarks.
Date: April 29, 1908
Creator: United States. Congress. Senate. Committee on Public Lands
Partner: UNT Libraries Government Documents Department

A Systematic Synopsis of the Muskrats

Description: From introduction: "Systematic account of the genus Fiber through study of over 1,000 specimens, chiefly well-prepared skins, accompanied by skulls, together with many odd skulls and skeletons."
Date: April 29, 1911
Creator: Hollister, N.
Partner: UNT Libraries Government Documents Department

Comparison of hecter fuel with export aviation gasoline

Description: Among the fuels which will operate at compression ratios up to at least 8.0 without preignition or "pinking" is hecter fuel, whence a careful determination of its performance is of importance. For the test data presented in this report the hecter fuel used was a mixture of 30 per cent benzol and 70 per cent cyclohexane, having a low freezing point, and distilling from first drop to 90 per cent at nearly a constant temperature, about 20 degrees c. below the average distillation temperature ("mean volatility") of the x gasoline (export grade). The results of these experiments show that the power developed by hecter fuel is the same as that developed by export aviation gasoline at about 1,800 r.p.m. at all altitudes. At lower speeds differences in the power developed by the fuels become evident. Comparisons at ground level were omitted to avoid any possibility of damaging the engine by operating with open throttle on gasoline at so high a compression. The fuel consumption per unit power based on weight, not volume, averaged more than 10 per cent greater with hecter than with x gasoline. The thermal efficiency of the engine when using hecter is less than when using gasoline, particularly at higher speeds. A generalization of the difference for all altitudes and speeds being 8 per cent. A general deduction from these facts is that more hecter is exhausted unburnt. Hecter can withstand high compression pressures and temperature without preignition. (author).
Date: January 29, 1920
Creator: Dickinson, H. C.; Gage, V. R. & Sparrow, S. W.
Partner: UNT Libraries Government Documents Department

Air force and moment for N-20 wing with certain cut-outs

Description: From Introduction: "The airplane designer often finds it necessary, in meeting the requirements of visibility, to remove area or to otherwise locally distort the plan or section of an airplane wing. This report, prepared for the Bureau of Aeronautics January 15, 1925, contains the experimental results of tests on six 5 by 30 inch N-20 wing models, cut out or distorted in different ways, which were conducted in the 8 by 8 foot wind tunnel of the Navy Aerodynamical Laboratory in Washington in 1924. The measured and derived results are given without correction for vl/v for wall effect and for standard air density, p=0.00237 slug per cubic foot."
Date: November 29, 1926
Creator: Smith, R. H.
Partner: UNT Libraries Government Documents Department

Preliminary flight tests of the N.A.C.A. Roots type aircraft engine supercharger

Description: "An investigation of the suitability of the N.A.C.A. Roots type aircraft engine supercharger to flight-operating conditions, as determined the effects of the use of the supercharger upon engine operation and airplane performance, is described in this report. Attention was concentrated on the operation of the engine-supercharger unit and on the improvement of climbing ability; some information concerning high speeds at altitude was obtained. The supercharger was found to be satisfactory under flight-operating conditions. Although two failures occurred during the tests, the causes of both were minor and have been eliminated" (p. 207).
Date: December 29, 1926
Creator: Gardiner, Arthur W. & Reid, Elliott G.
Partner: UNT Libraries Government Documents Department

An Investigation of the Use of Discharge Valves and an Intake Control for Improving the Performance of N.A.C.A. Roots Type Supercharger

Description: "This report presents the results of an analytical investigation on the practicability of using mechanically operated discharge valves in conjunction with a manually operated intake control for improving the performance of N. A. C. A. Roots type superchargers. These valves, which may be either of the oscillating or rotating type, are placed in the discharge opening of the supercharger and are so shaped and synchronized with the supercharger impellers that they do not open until the air has been compressed to the delivery pressure. The intake control limits the quantity of air compressed to engine requirements by permitting the excess air to escape from the compression chamber before compression begins" (p. 479).
Date: June 29, 1928
Creator: Schey, Oscar W. & Wilson, Ernest E.
Partner: UNT Libraries Government Documents Department

The effect of increased carburetor pressure on engine performance at several compression ratios

Description: The object of this investigation was to determine the effect of increasing the carburetor pressures from 30 to 40 inches of mercury, at compression ratios from 3.5 to 7.5, on the power, on the maximum cylinder pressures, on the fuel consumption, and on the other performance characteristics of an engine. A roots-type aircraft-engine supercharger was used to maintain the desired carburetor pressure.
Date: May 29, 1931
Creator: Schey, Oscar W. & Rollin, Vern G.
Partner: UNT Libraries Government Documents Department

Paris Aviation Salon, 1934

Description: This document reviews the Air show held in Paris in 1934. It includes charts and pictures of the aircraft which were from all parts of Europe.
Date: November 29, 1934
Partner: UNT Libraries Government Documents Department

Preliminary tests in the NACA free-spinning wind tunnel

Description: Typical models and the testing technique used in the NACA free-spinning wind tunnel are described in detail. The results of tests on two models afford a comparison between the spinning characteristics of scale models in the tunnel and of the airplanes that they represent.
Date: October 29, 1935
Creator: Zimmerman, C. H.
Partner: UNT Libraries Government Documents Department

Effect of body nose shape on the propulsive efficiency of a propeller

Description: Report presents the results of an investigation of the propulsive efficiency of three adjustable propellers of 10-foot diameter operated in front of four body nose shapes, varying from streamline nose that continued through the propeller plane in the form of a large spinner to a conventional open-nose radial-engine cowling. One propeller had airfoil sections close to the hub, the second had conventional round blade shanks, and the third differed from the second only in pitch distribution. The blade-angle settings ranged from 20 degrees to 55 degrees at the 0.75 radius.
Date: January 29, 1940
Creator: Stickle, George W.; Crigler, John L. & Naiman, Irven
Partner: UNT Libraries Government Documents Department

Preliminary investigation of the flying qualities of airplanes

Description: "The National Advisory Committee for Aeronautics is undertaking an investigation of the flying qualities of airplanes. The work consists in the determination of the significant qualities susceptible of measurement, the development of the instruments required to make the measurements, and the accumulation of data on the flying qualities of existing airplanes, which data are to serve as a basis for quantitative specifications for the flying qualities of future designs" (p. 449).
Date: March 29, 1940
Creator: Soulé, H. A.
Partner: UNT Libraries Government Documents Department

The Calculated Effect of Various Hydrodynamic and Aerodynamic Factors on the Take-Off of a Large Flying Boat

Description: Report presents the results of an investigation made to determine the influence of various factors on the take-off performance of a hypothetical large flying boat by means of take-off calculations. The factors varied in the calculations were size of hull (load coefficient), wing setting, trim, deflection of flap, wing loading, aspect ratio, and parasite drag. The take-off times and distances were calculated to the stalling speeds and the performance above these speeds was separately studied to determine piloting technique for optimum take-off.
Date: April 29, 1940
Creator: Olson, R. E. & Allison, J. M.
Partner: UNT Libraries Government Documents Department

Measurement of Density of Liquid UF6

Description: This report describes a method and apparatus used to determine the density of liquid sodium hexafluoride. The report includes a drawing of the density cell used in the experiment.
Date: March 29, 1942
Creator: Priest, Homer F.
Partner: UNT Libraries Government Documents Department

Theory of High Frequency Rectification by Silicon Crystals

Description: The excellent performance of British ''red dot'' crystals is explained as due to the knife edge contact against a polished surface. High frequency rectification depends critically on the capacity of the rectifying boundary layer of the crystal. C. For high conversion efficiency, the product of this capacity and of the ''forward'' (bulk) resistance R{sub b} of the crystal must be small. For a knife edge, this product depends primarily on the breadth of the knife edge and very little upon its length. The contact can therefore have a rather large area which prevents burn-out. For a wavelength of 10 cm. the computations show that the breadth of the knife edge should be less than about 10{sup -3} cm. For a point contact the radius must be less than 1.5 x 10{sup -3} cm. and the resulting small area is conductive to burn-out. The effect of ''tapping'' is probably to reduce the area of contact.
Date: October 29, 1942
Creator: Bethe, H.A.
Partner: UNT Libraries Government Documents Department

Stability of Split Hollow Cylinders

Description: Abstract: "The behavior of radially split hollow cylinders upon heating is discussed."
Date: June 29, 1944
Creator: Karush, William & Monk, A. T.
Partner: UNT Libraries Government Documents Department

Longitudinal characteristics and aileron effectiveness of a midwing airplane from high-speed wind tunnel tests

Description: Report presenting wind-tunnel tests of a 0.175-scale model of a midwing airplane in order to determine the high-speed longitudinal characteristics, to test devices for improving longitudinal control at high Mach numbers, and to determine the aileron effectiveness at high Mach numbers. Force and moment coefficients are computed from test data. Control forces, elevator angle, and aileron angle for several flight conditions are predicted.
Date: September 29, 1944
Creator: Hall, Charles F. & Mannes, Robert L.
Partner: UNT Libraries Government Documents Department

On the flow of a compressible fluid by the hodograph method 2: fundamental set of particular flow solutions of the Chaplygin differential equation

Description: From Summary: "The differential equation of Chaplygin's jet problem is utilized to give a systematic development of particular solutions of the hodograph flow equations, which extends the treatment of Chaplygin into the supersonic range and completes the set of particular solutions. The particular solutions serve to place on a reasonable basis the use of velocity correction formulas for the comparison of incompressible and compressible flows. It is shown that the geometric-mean type of velocity correction formula introduced in part I has significance as an over-all type of approximation in the subsonic range."
Date: September 29, 1944
Creator: Garrick, I. E. & Kaplan, Carl
Partner: UNT Libraries Government Documents Department

On the Flow of a Compressible Fluid by the Hodograph Method. II - Fundamental Set of Particular Flow Solutions of the Chaplygin Differential Equation

Description: From Summary: "The differential equation of Chaplygin's jet problem is utilized to give a systematic development of particular solutions of the hodograph flow equations, which extends the treatment of Chaplygin into the supersonic range and completes the set of particular solutions. The particular solutions serve to place on a reasonable basis the use of velocity correction formulas for the comparison of incompressible and compressible flows. It is shown that the geometric-mean type of velocity correction formula introduced in part I has significance as an over-all type of approximation in the subsonic range."
Date: September 29, 1944
Creator: Garrick, I. E. & Kaplan, Carl
Partner: UNT Libraries Government Documents Department

Wind dilution required to reduce to tolerance levels the activity due to xenon and iodine in HEW dissolver off-gases

Description: The radio-active xenon and iodine evolved during the dissolution of the uranium may present a health hazard within certain areas around the base of the stack through which the dissolver off-gases are discharged. Since the concentration of these elements in the uranium metal is directly proportional to the power of the pile* and is related to decay period of the metal in accordance with their half-lifes, the maximum rate of discharge of these elements from the stack at H.E.W. can be estimated form existing Clinton data. The required wind dilution to reduce the discharging activation to tolerance levels can then be calculated. The time with respect to the start of the metal dissolution at which the maximum rates of discharge will be attained can also be roughly estimated form existing Clinton data. 3 figs., 3 tabs.
Date: September 29, 1944
Creator: Dreher, J.L.
Partner: UNT Libraries Government Documents Department

Extension of Useful Operating Range of Axial-Flow Compressors by Use of Adjustable Stator Blades

Description: "A theory has been developed for resetting the blade angles of an axial-flow compressor in order to improve the performance at speeds and flows other than the design and thus extend the useful operating range of the compressor. The theory is readily applicable to the resetting of both rotor and stator blades or to the resetting of only the stator blades and is based on adjustment of the blade angles to obtain lift coefficients at which the blades will operate efficiently. Calculations were made for resetting the stator blades of the NACA eight-stage axial-flow compressor for 75 percent of design speed and a series of load coefficients ranging from 0.28 to 0.70 with rotor blades left at the design setting" (p. 425).
Date: December 29, 1944
Creator: Sinnette, John T., Jr. & Voss, William J.
Partner: UNT Libraries Government Documents Department

FILM FORMATION IN "W" ANNULUS

Description: No Description Available.
Date: January 29, 1945
Creator: Larson, R E & Szulinski, M J
Partner: UNT Libraries Government Documents Department