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Calorimetry progress report

Description: The constant temperature bath is in operation. A ballistic type instability was detected in the calorimeter circuits and corrected by grounding the bath. Calorimeters 37, 39, 40, and 43 have been installed are now being run. Calorimeter 40 was found to be unstable, and is to be disassembled and examined for the trouble. Calorimeter 46 was finished and placed in operation. Construction details are discussed. Six Logac samples were run in Calorimeter 38. Tests of this calorimeter are in Table 1. Comparison of Calorimeter 38 in a water bath and in an ice bath is shown in Table 2. Good results were obtained for such a drastic change in environment. Calorimeter 38 was turned over to Calorimetric Assay marking the end of the tests of this particular microcalorimeter. Calorimeter 44 was completed and installed in the ice bath. Table 4 shows the results of tests. The zero bridge potential is small and is very stable compared to Calorimeter 38. The comparison of the values with those from Calorimetric Assay is summarized in Table 3. The characteristics of Calorimeter 44 are shown in Table 5. Construction details are given for the platinum-manganin bridge-type thermometer. An instrument was needed that could be used to detect bath temperature changes of the order of 0.0005 C. The thermometer was installed in the bath on March 29, 1949. With the bridge current at 10 milliamperes, the measured sensitivity is 2.5 microvolts per 0.001 C change in temperature. The temperature difference between the inner and outer walls of a quartz capillary containing polonium was calculated. The volume of polonium in the capillaries was recalculated and the density re-evaluated.
Date: April 1, 1949
Creator: Parks, J. R.
Partner: UNT Libraries Government Documents Department

A report on lithium, sodium, and liquid neutron sources

Description: The objectives in producing neutron sources are to produce uniform products of as high efficiencies as possible from the neutron yielding elements and to do this in the safest manner. The purpose of the present work was to improve the methods of preparing sources and at the same time increase the types of sources available. Lithium, sodium, and their compounds were chosen because the neutron fluxes and energies are low, thus making the experimental work less hazardous to the operator. Also, the elements are quite reactive, so that techniques which are successful with them can be easily adapted to other materials. Solvents for polonium, ways of mixing polonium and target, neutron yields, reproducibility, decay of the sources, means of recovering polonium, and materials for containers, were investigated.
Date: April 22, 1949
Creator: Bentz, L.L.
Partner: UNT Libraries Government Documents Department

Simplified Ionization Chamber

Description: Construction and operation of a simplified ionization chamber.
Date: April 20, 1949
Partner: UNT Libraries Government Documents Department

Determination of the Number of Double Bonds in Less-Than-Milligram Amounts of Unsaturated Fatty Acids by Catalytic Hydrogenation in the Warburg Apparatus

Description: Report discussing the determination of the number of olefinic double bonds in less-than-milligram amounts of unsaturated fatty acid derivatives using Barcroft-Warburg tissue respirometer as a manometric microhydrogenation apparatus.
Date: April 1949
Creator: Mead, James F. & Howton, David R.
Partner: UNT Libraries Government Documents Department

Investigations of an Annular Diffuser-Fan Combination Handling Rotating Flow

Description: Memorandum presenting an investigation of two annular diffusers of different conical angles of expansion but constant outer diameters with rotating flow behind a fan. The performance characteristics are determined and the rotational-kinetic-energy effects on the overall energy transformation are observed over a range of inlet mach numbers from 0.1 to 0.44 and angles of flow up to 28 degrees.
Date: April 25, 1949
Creator: Schwartz, Ira R.
Partner: UNT Libraries Government Documents Department

A Preliminary Outline of Desirable Research in the Geochemistry of Uranium

Description: Report outlining fields of study for a program of research in the geochemistry of uranium. From Abstract: "Various specific topics and projects that apply to these fields of study are suggested."
Date: April 1949
Creator: Rabbitt, J. C.; Rubey, W. W.; Butler, A. P., Jr.; Lovering, T. S. & McKelvey, V. E.
Partner: UNT Libraries Government Documents Department

Effect of Increase in Afterbody Length on the Hydrodynamic Qualities of a Flying-Boat Hull of High Length-Beam Ratio

Description: Report presenting an investigation to determine the effects of increased afterbody length on the hydrodynamic qualities of a model of a flying boat with a hull with a length-beam ratio of 15. Results regarding longitudinal stability, spray characteristics, excess thrust for take-off, landings in waves, and a summary chart are provided.
Date: April 1949
Creator: Kapryan, Walter J. & Clement, Eugene P.
Partner: UNT Libraries Government Documents Department

A Mathematical Theory of Plasticity Based on the Concept of Slip

Description: Note presenting a theory of plasticity based on the concept of slip as proposed for the relationship between stress and strain for initially isotropic materials in the strain-hardening range. The theory is an extension to polyaxial stress conditions of the conventional uniaxial stress-strain relation, and time-dependent effects, such as creep and stress relaxation, are not considered.
Date: April 1949
Creator: Batdorf, S. B. & Budiansky, Bernard
Partner: UNT Libraries Government Documents Department

Summary of the Availability and Performance Problems of High Octane Number Fuels

Description: Memorandum presenting a study to determine the possible blending agents or additives that may be used to supplement current high performance number, rich rating components in future aviation fuels. The study indicated that such high rich rating blending agents as toluene and xylene cannot be made available in sufficient quantities to maintain the rich rating performance of the fuels when reducing the lead content from 4.6 to 3.0 ml per gallon.
Date: April 15, 1949
Creator: NACA Committee on Aircraft Fuels
Partner: UNT Libraries Government Documents Department

Line-Vortex Theory for Calculation of Supersonic Downwash

Description: "The perturbation field induced by a line vortex in a supersonic stream and the downwash behind a supersonic lifting surface are examined to establish approximate methods for determining the downwash behind supersonic wings. Lifting-lines methods are presented for calculating supersonic downwash. A bent lifting-line method is proposed for computing the downwash field behind swept wings. When applied to triangular wings with subsonic leading edges, this method gives results that, in general, are in good agreement with the exact linearized solution" (p. 635).
Date: April 29, 1949
Creator: Mirels, Harold & Haefeli, Rudolph C.
Partner: UNT Libraries Government Documents Department

Effect of Various Compounds in Use With Airplane Engines Upon Foaming of Aircraft Lubricating Oil

Description: Report presenting an investigation of aircraft lubricating oil that is contaminated with various materials used in connection with airplane engines or contained in the fuel. Over 60 of the materials have been tested to determine their influence on the foaming of an aircraft lubricating oil. All but 13 of the compounds were found to have a small or negligible effect, but the other 13 were found to be strong foaming agents.
Date: April 1949
Creator: McBain, J. W. & Woods, W. W.
Partner: UNT Libraries Government Documents Department

Equations of State of Elements Based on the Generalized Fermi-Thomas Theory

Description: The Fermi-Thomas model has been used to derive the equation of state of matter at high pressures and at various temperatures. Calculations have been carried out both without and with the exchange terms. Discussion of similarity transformations lead to the virial theorem and to correlation of solutions for different Z-values.
Date: April 30, 1949
Creator: Feynman, R.P.; Metropolis, N. & Teller, E.
Partner: UNT Libraries Government Documents Department

Further experiments on the flow and heat transfer in a heated turbulent air jet

Description: Measurements have been made of the mean total-head and temperature fields in a round turbulent jet with various initial temperatures. The results show that the jet spreads more rapidly as its density becomes lower than that of the receiving medium, even when the difference is not sufficiently great to cause measurable deviations from the constant-density, dimensionless, dynamic-pressure profile function. Rough analytical considerations have given the same relative spread. The effective "turbulent Prandtl number" for a section of the fully developed jet was found to be equal to the true (laminar) Prandtl number within the accuracy of measurement. (author).
Date: April 1949
Creator: Corrsin, Stanley & Uberoi, Mahinder S.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a wing with quarter-chord line swept back 35 degrees, aspect ratio 4, taper ratio 0.6, and NACA 65A006 airfoil section: Transonic-bump method

Description: From Introduction: "This paper presents the results of the investigation of wing-alone and wing-fuselage combinations employing a wing with the quarter-chord line swept back 35^o, aspect ratio 4, taper ratio 0.6, and NACA 65A006 airfoil section."
Date: April 21, 1949
Creator: Sleeman, William C., Jr. & Becht, Robert E.
Partner: UNT Libraries Government Documents Department

Critical shear stress of infinitely long, simply supported plate with transverse stiffeners

Description: From Summary: "A theoretical solution is given for the critical shear stress of an infinitely long, simply supported, flat plate with identical, equally spaced, transverse stiffeners of zero torsional stiffness. Results are obtained by means of the Lagrangian multiplier method and are presented in the form of design charts. Experimental results are included and are found to be in good agreement with the theoretical results."
Date: April 1949
Creator: Stein, Manuel & Fralich, Robert W.
Partner: UNT Libraries Government Documents Department

High-lift and lateral control characteristics of an NACA 652-215 semispan wing equipped with plug and retractable ailerons and a full-span slotted flap

Description: Report presenting a wind-tunnel investigation at low Mach and Reynolds numbers to determine the high-lift and lateral control characteristics of a semispan wing of NACA 65(sub 2)-215 airfoil section equipped with a 25-percent-chord, full-span, slotted flap and plug and retractable ailerons. The ailerons were located at the 70-percent-chord station over the outer 49 percent of the wing semispan and were fabricated in five spanwise segments. Results regarding the wing aerodynamic characteristics, lateral control characteristics, comparison of lateral control characteristics of the plug and retractable ailerons, and a comparison of lateral control characteristics of the plug and retractable ailerons on the present wing with similar ailerons on an NACA 65-210 wing are provided.
Date: April 1949
Creator: Fischel, Jack & Vogler, Raymond D.
Partner: UNT Libraries Government Documents Department

Wind-tunnel investigation of the opening characteristics, drag, and stability of several hemispherical parachutes

Description: Report presenting an investigation to determine the opening characteristics of several hemispherical parachutes at airspeeds up to 200 miles per hour and to study the influence of the parachute design variables on the opening characteristics. The effects of design variables on the drag and stability characteristics of the parachutes were also evaluated.
Date: April 1949
Creator: Scher, Stanley H. & Gale, Lawrence J.
Partner: UNT Libraries Government Documents Department

A review of instruments developed for the measurement of the meteorological factors conductive to aircraft icing

Description: Report presenting a review of the status of instruments suitable for the measurement of the meteorological factors conducive to aircraft icing. Nine instruments which appear to be the most promising for obtaining meteorological data are discussed and recommendations for their continued use and development are provided.
Date: April 26, 1949
Creator: Jones, Alun R. & Lewis, William
Partner: UNT Libraries Government Documents Department

Boundary Layer Theory, Part 2, Turbulent Flows

Description: From Summary: "The flow laws of the actual flows at high Reynolds numbers differ considerably from those of the laminar flows treated in the preceding part. These actual flows show a special characteristic, denoted as turbulence. The character of a turbulent flow is most easily understood the case of the pipe flow. Consider the flow through a straight pipe of circular cross section and with a smooth wall. For laminar flow each fluid particle moves with uniform velocity along a rectilinear path."
Date: April 1949
Creator: Schlichting, H.
Partner: UNT Libraries Government Documents Department

Effects of high-lift and stall-control devices, fuselage, and horizontal tail on a wing swept back 42 degrees at the leading edge and having symmetrical circular-arc airfoils sections at a Reynolds number of 6.9 x 10(exp 6)

Description: Report presenting an investigation of the low-speed characteristics of a wing swept back 42 degrees at the leading edge and having various high-lift and stall-control devices and fuselage and horizontal tail vertical positions. Results regarding the characteristics of the basic wing, leading-edge flap investigation, wing fuselage investigation, and horizontal tail investigation are provided.
Date: April 20, 1949
Creator: Woods, Robert L. & Spooner, Stanley H.
Partner: UNT Libraries Government Documents Department