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Natural History of the Queen Charlotte Islands, British Columbia. Natural History of the Cook Inlet Region, Alaska (open access)

Natural History of the Queen Charlotte Islands, British Columbia. Natural History of the Cook Inlet Region, Alaska

Results of 1900 expedition on Queen Charlotte Islands describing natural history.
Date: September 26, 1901
Creator: Osgood, Wilfred H.
Object Type: Report
System: The UNT Digital Library
A Biological Investigation of the Athabaska-Mackenzie Region (open access)

A Biological Investigation of the Athabaska-Mackenzie Region

From introduction: "Report of 1901 expedition of Athabaska-Mackenzie region to obtain representative collections of the mammals, birds, and plants."
Date: October 26, 1908
Creator: Preble, Edward A.
Object Type: Report
System: The UNT Digital Library
Investigation of Air Flow in Open-Throat Wind Tunnels (open access)

Investigation of Air Flow in Open-Throat Wind Tunnels

"Tests were conducted on the 6-inch wind tunnel of the National Advisory Committee for Aeronautics to form a part of a research on open-throat wind tunnels. The primary object of this part of the research was to study a type of air pulsation which has been encountered in open-throat tunnels, and to find the most satisfactory means of eliminating such pulsations. In order to do this it was necessary to study the effects of different variable on all of the important characteristics of the tunnel" (p. 399).
Date: September 26, 1928
Creator: Jacobs, Eastman N.
Object Type: Report
System: The UNT Digital Library
Experimental and analytical determination of the motion of hydraulically operated valve stems in oil engine injection systems (open access)

Experimental and analytical determination of the motion of hydraulically operated valve stems in oil engine injection systems

This research on the pressure variations in the injection system of the N.A.C.A. Spray Photography Equipment and on the effects of these variations on the motion of the timing valve stem was undertaken in connection with the study of fuel injection systems for high-speed oil engines. The methods of analysis of the pressure variations and the general equation for the motion of the spring-loaded stem for the timing valve are applicable to a spring-loaded automatic injection valve, and in general to all hydraulically operated valves. A sample calculation for a spring-loaded automatic injection valve is included.
Date: December 26, 1928
Creator: Gelalles, A. G. & Rothrock, A. M.
Object Type: Report
System: The UNT Digital Library
The NACA Apparatus for Studying the Formation and Combustion of Fuel Sprays and the Results From Preliminary Tests (open access)

The NACA Apparatus for Studying the Formation and Combustion of Fuel Sprays and the Results From Preliminary Tests

"This report describes the apparatus as designed and constructed at the Langley Memorial Aeronautical Laboratory, for studying the formation and combustion of fuel sprays under conditions closely simulating those occurring in a high-speed compression-ignition engine. The apparatus consists of a single-cylinder modified test engine, a fuel-injection system so designed that a single charge of fuel can be injected into the combustion chamber of the engine, an electric driving motor, and a high-speed photographic apparatus. The cylinder head of the engine has a vertical-disk form of combustion chamber whose sides are glass windows" (p. 549).
Date: August 26, 1931
Creator: Rothrock, A. M.
Object Type: Report
System: The UNT Digital Library
The Aerodynamic Characteristics of Airfoils at Negative Angles of Attack (open access)

The Aerodynamic Characteristics of Airfoils at Negative Angles of Attack

From Introduction: "The present report gives all the results, including those published in reference 1 and the results of previously un-published tests tests of the airfoils at positive angles of attack."
Date: February 26, 1932
Creator: Anderson, Raymond F.
Object Type: Report
System: The UNT Digital Library
The International Metric System of Weights and Measures (open access)

The International Metric System of Weights and Measures

General overview of the metric system.
Date: May 26, 1932
Creator: unknown
Object Type: Report
System: The UNT Digital Library
The drag of two streamline bodies as affected by protuberances and appendages (open access)

The drag of two streamline bodies as affected by protuberances and appendages

This report presents the results of wind tunnel tests of two airship models conducted to determine the drag coefficients at zero pitch, and the effect of fins and cars and of flat and streamlined protuberances located at various positions along the hull. During the investigation the stern of one model was rounded off to produce a blunter shape. The extreme range of the Reynolds number based on the over-all length of the models was from 1,300,000 to 33,000,000. At large values of the Reynolds number the streamlined protuberance affected the drag very little, and the additional drag caused by the flat protuberance was less than the calculated drag by the protuberance alone. The fins and cars together increased the bare-hull drag about 20 per cent.
Date: September 26, 1932
Creator: Abbott, Ira H.
Object Type: Report
System: The UNT Digital Library
Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings 5: Clark Y Biplane Cellule - NACA Cowled Nacelle - Tractor Propeller (open access)

Tests of Nacelle-Propeller Combinations in Various Positions with Reference to Wings 5: Clark Y Biplane Cellule - NACA Cowled Nacelle - Tractor Propeller

"This report is the fifth of a series giving the results obtained from wind tunnel tests on the interference drag and propulsive efficiency of nacelle-propeller-wing combinations. This report gives results of tests of an NACA cowled air-cooled engine nacelle with tractor propeller located in 12 positions with reference to a Clark Y biplane cellule" (p. 603).
Date: January 26, 1934
Creator: Valentine, E. Floyd
Object Type: Report
System: The UNT Digital Library
Heat transfer from finned metal cylinders in an air stream (open access)

Heat transfer from finned metal cylinders in an air stream

This report presents the results of tests made to supply design information for the construction of metal fins for the cooling of heated cylindrical surfaces by an air stream. A method is given for determining fin dimensions for a maximum heat transfer with the expenditure of a given amount of material for a variety of conditions of air flow and metals.
Date: April 26, 1934
Creator: Biermann, Arnold E. & Pinkel, Benjamin
Object Type: Report
System: The UNT Digital Library
The effect of baffles on the temperature distribution and heat-transfer coefficients of finned cylinders (open access)

The effect of baffles on the temperature distribution and heat-transfer coefficients of finned cylinders

This report presents the results of an investigation to determine the effect of baffles on the temperature distribution and the heat-transfer coefficient of finned cylinders. The tests were conducted in a 30-inch wind tunnel on electrically heated cylinders with fins of 0.25 and 0.31 inch pitch. The results of these tests showed that the use of integral baffles gave a reduction of 31.9 percent in the rear wall temperatures and an increase of 54.2 percent in the heat transfer coefficient as compared with a cylinder without baffles.
Date: September 26, 1934
Creator: Schey, Oscar W. & Rollin, Vern G.
Object Type: Report
System: The UNT Digital Library
Effects of air-fuel spray and flame formation in a compression-ignition engine (open access)

Effects of air-fuel spray and flame formation in a compression-ignition engine

"High-speed motion pictures were taken at the rate of 2,500 frames per second of the fuel spray and flame formation in the combustion chamber of the NACA combustion apparatus. The compression ratio was 13.2 and the speed 1,500 revolutions per minute. An optical indicator was used to record the time-pressure relationship in the combustion chamber. The air-fuel ratio was varied from 10.4 to 365. The results showed that as the air-fuel ratio was increased definite stratification of the charge occurred in the combustion chamber even though moderate air flow existed. The results also showed the rate of vapor diffusion to be relatively slow" (p. 119).
Date: August 26, 1935
Creator: Rothrock, A. M. & Waldron, C. D.
Object Type: Report
System: The UNT Digital Library
Comparative Flight and Full-Scale Wind-Tunnel Measurements of the Maximum Lift of an Airplane (open access)

Comparative Flight and Full-Scale Wind-Tunnel Measurements of the Maximum Lift of an Airplane

"Determinations of the power-off maximum lift of a Fairchild 22 airplane were made in the NACA full-scale wind tunnel and in flight. The results from the two types of test were in satisfactory agreement. It was found that, when the airplane was rotated positively in pitch through the angle of stall at rates of the order of 0.1 degree per second, the maximum lift coefficient was considerably higher than that obtained in the standard tests, in which the forces are measured with the angles of attack fixed. Scale effect on the maximum lift coefficient was also investigated" (p. 161).
Date: October 26, 1937
Creator: Silverstein, Abe; Katzoff, S. & Hootman, James A.
Object Type: Report
System: The UNT Digital Library
The Transition Phase in the Take-Off of an Airplane (open access)

The Transition Phase in the Take-Off of an Airplane

Report presents the results of an investigation to determine the character and importance of the transition phase between the ground run and steady climb in the take-off of an airplane and the effects of various factors on this phase and on the air-borne part of the take-off as a whole. The information was obtained from a series of step-by-step integrations, which defined the motion of the airplane during the transition and which were based on data derived from actual take-off tests of a Verville AT airplane. Both normal and zoom take-offs under several loading and take-off speed conditions were considered.
Date: October 26, 1937
Creator: Wetmore, J. W.
Object Type: Report
System: The UNT Digital Library
Determination of boundary-layer transition on three symmetrical airfoils in the NACA full-scale wind tunnel (open access)

Determination of boundary-layer transition on three symmetrical airfoils in the NACA full-scale wind tunnel

For the purpose of studying the transition from laminar to turbulent flow, boundary-layer measurements were made in the NACA full-scale wind tunnel on three symmetrical airfoils of NACA 0009, 0012, and 0018 sections. The effects of variations in lift coefficient, Reynolds number, and airfoil thickness on transition were investigated. Air speed in the boundary layer was measured by total-head tubes and by hot wires; a comparison of transition as indicated by the two techniques was obtained. The results indicate no unique value of Reynolds number for the transition, whether the Reynolds number is based upon the distance along the chord or upon the thickness of the boundary layer at the transition point. In general, the transition is not abrupt and occurs in a region that varies in length as a function of the test conditions.
Date: May 26, 1938
Creator: Silverstein, Abe & Becker, John V.
Object Type: Report
System: The UNT Digital Library
Specifications for the Freezing Point Method for Determination of the Amount of HF in UF₆ (open access)

Specifications for the Freezing Point Method for Determination of the Amount of HF in UF₆

From introduction: "You will find enclosed the specifications for the freezing point method for determination of the amount of HF in UF₆. The specification for cleaning new shipping containers is also included."
Date: February 26, 1944
Creator: Priest, Homer F.
Object Type: Report
System: The UNT Digital Library
Maximum Force of a Warped Rod Against a Rigid Constraint (open access)

Maximum Force of a Warped Rod Against a Rigid Constraint

Abstract. Given the maximum intrinsic curvature of a rod, the maximum force required to confine it between parallel rigid walls is computed.
Date: October 26, 1944
Creator: Martin, A. V.
Object Type: Report
System: The UNT Digital Library
Factors Affecting the Precipitation of Tubanyl Peroxide from Gunk Solutions at Reduced Temperatures (open access)

Factors Affecting the Precipitation of Tubanyl Peroxide from Gunk Solutions at Reduced Temperatures

This paper reports work carried out to determine the factors necessary to give a filterable precipitation and determine the effects of these factors on the quantitativeness of the precipitation, and how any tendency to increase the tuballoy solubility may be overcome.
Date: March 26, 1945
Creator: Brown, K. B.; Davis, W. C.; Wagner, E. L. & Miller, A. J.
Object Type: Report
System: The UNT Digital Library
A Solubility Method of the Determination of Non-Volatile Material in Tetrachloride Charges (open access)

A Solubility Method of the Determination of Non-Volatile Material in Tetrachloride Charges

Abstract: "This report suggests using methyl acetate extraction of charge material as a means of determining the non-volatile residue. It is shown that the volatile constituents of charge material are all extremely soluble in methyl acetate whereas the non-volatile materials are quite insoluble. Percent NVH on several samples of charge material by this method are reported and discussed."
Date: April 26, 1945
Creator: Sterett, Charles & Van Wazer, John R.
Object Type: Report
System: The UNT Digital Library
Development of Equipment for the Purification of Mercury by Distillation (open access)

Development of Equipment for the Purification of Mercury by Distillation

Abstract: "An investigation of the mercury salvage program has resulted in the development of an improved high compacity type of distillation apparatus. The still, electrically heated and essentially automatic in its operation, will produce at a rate greater than 75 pounds per hour and develop a product 99.99% pure or better. This still will handle the lowest grade crude of amalgam that can pass through the feed lines and will continue to develop a pure prodcut for comparatively long periods of time. The clean-out operation is amazingly simple and convenient and may be done within one-half hour while the apparatus itself is still hot. Two models of this design are scheduled for installation in a mercury recovery room of the Alpha Analytical Department of Building No. 9207."
Date: May 26, 1945
Creator: Lee, J. E. & Susano, C. D.
Object Type: Report
System: The UNT Digital Library
Progress Report on Corrosion Tests in TCl₄ (open access)

Progress Report on Corrosion Tests in TCl₄

This report describes progress in testing the corrosion resistance of alloys of TCl₄. The steps and conditions of the testing procedures are given as well as conclusions and photos of TCl₄.
Date: May 26, 1945
Creator: Mash, Donald R.
Object Type: Report
System: The UNT Digital Library
Nitrous Oxide Supercharging of an Aircraft-Engine Cylinder (open access)

Nitrous Oxide Supercharging of an Aircraft-Engine Cylinder

Report discussing tests to determine the performance of an aircraft engine cylinder using nitrous oxide to provide additional supercharging. The test results of injecting it as a gas and calculated results of injecting it as a liquid are described.
Date: June 26, 1945
Creator: Tauschek, Max J.; Corrington, Lester C. & Huppert, Merle C.
Object Type: Report
System: The UNT Digital Library
A Note on the Kinetics of Homogeneous Piles (open access)

A Note on the Kinetics of Homogeneous Piles

Abstract. In investigating stability of a homogeneous pile it has been customary to assume that the production of bubbles follows the production of power instantaneously. Here we investigate the implications of introduction of an intermediate dissolved gas stage under two hypotheses on the formation of bubbles from this dissolved gas. It is seen that this additional stage tends to make the pile unstable.
Date: June 26, 1945
Creator: Wilkins, J. Ernest, Jr., 1923-2011
Object Type: Report
System: The UNT Digital Library
The Solubility of Helium in Tuballoy (open access)

The Solubility of Helium in Tuballoy

This technical report summarizes the work done in attempting to determine the solubility of helium in tuballoy. In general, the method used has been to allow the tuballoy to stand in contact with helium at one atmosphere presume at a fixed temperature for an extended period, then to pump off the excess helium to a low pressure in as short a time as possible (10-6 mm of Hg or less). The system was then closed off and the pressure increase was measured by a suitable gauge as a function of time. The metal was employed in the form of a powder in early measurements, and later as massive metal. The experimental techniques are described in the report.
Date: June 26, 1945
Creator: Seltz , H. & Young, C. W.
Object Type: Report
System: The UNT Digital Library