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1963 Research Highlights of the National Bureau of Standards

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1963 Research Highlights of the National Bureau of Standards H"..,'1 1963 RESEARCH HIGHLIGHTS V.:- \ OF THE v "i',: ATIONAL BUREAU OF STANDARDS ;,:»r?->.7-V NNUAL REPORT : The groups to be served by the specialized services of the National Bureau of Standards were well defined by the Congress at the time the Bureau was founded. The Committee on Coinage, Weights and Measures in recommending to the House of Representatives in May of 1900 that a National Bureau of Standards be established, said "It is therefore the unanimous opinion of your committee that no more essential aid could be given to manufacturing, commerce, the makers of scientific apparatus, the scientific work of the Government, of schools, colleges and universities, than by the establishment of the institution pro- posed in this bill." This statement, which provides an enduring focus for the activities of the Bureau, will be engraved in stone in the lobby of the Administra- tion Building at the new laboratory site near Gaithersburg, Maryland. A. V. Astin, Director, National Bureau of Standards. UNITED STATES DEPARTMENT OF COMMERCE Luther H. Hodges, Secretary J. Herbert Hollomon, Assistant Secretary for Science and Technology NATIONAL BUREAU OF STANDARDS A. V. Astin, Director 1963 Research Highlights of the National Bureau of Standards Annual Report, Fiscal Year 1963 December 1963 Miscellaneous Publication 255 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C., 20402 - Price $1.00 Library of Congress Catalog Card Number: 6-23979 Contents Page 1. General review 1 Basic measurement standards 2 Standard reference data 7 National Standard Reference Data System 8 Engineering measurement standards 9 Standard reference materials . 11 Special central missions 14 Radio propagation 14 Data-processing systems 15 Building research 15 Consulting services 15 Background research 18 Internal support activities 19 International activities 19 Administrative activities 21 Publications and technical information 24 2. Highlights of the research program 26 2.1. Physics, electronics, and measurement standards 26 2.1.1. Metrology 26 A new standard of spectral irradiance 27 Basis for color measurement amended 27 Calibration of fiashtubes 28 Fluorescent lamp measurements intercompared 28 Equipment developed for calibrating thermal detectors 28 Equipment developed for densitometric calibrations 29 Refractive index of calcium fluoride 30 Generalized lens-bending procedure developed 30 Technique for deriving principal curvatures of wave fronts ... 30 Image evaluation 31 Measurement of wave fronts 31 Stored microfilms inspected 31 Microcopy chart designed 31 Method developed for measuring thiosulfate in processed film. 32 Length measurement research 32 Thermal expansion measurement capability extended 32 Wave-front-shearing interferometer 32 Screw thread standardization 33 Laser produces fringes over 200-meter path 33 Cockpit lighting in TFX aircraft 33 Accuracy of spectral transmittance standards investigated. 33 Goniophotometry 34 2.1.2. Mechanics 34 Vibration amplitudes measured . 35 Microphone calibration 35 Portable tube designed for sound-absorption measurements. ... 35 Cavitation data obtained 36 Measurement of impact sound transmission in buildings 36 Infrasonic waves studied in the atmosphere and in the earth ... 36 Audiometry research 38 Improvements sought in pressure and vacuum measurements . 38 Computer techniques applied in turbulence studies 39 Boundary layer instability and effect of roughness 39 Standards designed for million-pound forces 40 Compact precision centrifuge constructed 41 Rheological constitutive equations 41 Review of volume relaxations in polymers 41 Hypersonic combustion 42 Reference fuel control test facilities operated at the Bureau. ... 42 Sla tic electric failure of aircraft engine fuel hose 43 Reference tables for a new thermocouple to be established. ... 43 Flame speed inhibitors 44 High-temperature thermocouples 44 III 2. Highlights of the research program—Continued 2.1. Physics, electronics, and measurement standards—Continuea Page 2.1.3. Electricity 44 Absolute measurements 44 Impedance of dry cells 45 Battery depolarizers at high temperatures 46 Zener diodes as voltage standards 46 Membrane potentials in fused salts 46 Differential a-c-d-c transfer standard 47 Magnetism 47 Dielectric behavior of liquids and supercooled liquids at ele- vated pressures 48 Precision measurement of the dielectric constant of solid bodies. 49 Humidity-time studies of dielectric constant and loss index. ... 49 Theoretical studies on dielectrics 50 Chain-folding in polymer crystals 50 Dielectric properties of polymers 50 Dielectric properties of dipolar chain compounds 50 Microwave absorption in compressed gases 51 High voltage 52 2.1.4. Radio standards 52 Theoretical physics 53 Radio standards physics 53 Fort Collins standard radio transmitting site 53 Atomic frequency standard research 54 Quantum electronics 55 Radio and microwave materials 56 Magnetics 56 Dielectrics 57 Conductivity 57 Materials synthesis 57 Plasma 57 Microwave interactions with plasma 58 Speed of light (diffraction correction) 58 Stark voltmeter 59 Radio standards engineering .• . 59 Low-frequency calibration 59 High-frequency standards and calibration 60 Microwave standards and calibration 62 Fabry-Periot interferometer used as a dilatometer 64 2.1.5. Heat 65 Molecular energy levels program 65 Plasma transport processes 66 Automatic thermocouple comparator 66 Thermodynamic properties of light-element compounds 67 Computer analysis of low-temperature heat-capacity data. ... 68 Thermal diffusivity standards 69 Microwave spectroscopy 69 Nuclear orientation 69 Shock wave reaction kinetics 69 Thermodynamic properties of gases at high temperature 70 2.1.6. Atomic physics 71 Continuum states in rare gases 71 Plasma and astrophysics 74 Atomic energy levels 74 Wavelength standards 75 Infrared spectroscopy of gases 75 Shapes of rotational lines as influenced by pressure 76 Absorption spectra of solids 76 Solid state physics 76 Electron optics 77 Measuring velocity of light 77 Optical pumping 77 Magnetic moment of the proton 78 Experimental atomic collisions 78 2.1.7. Radiation physics 78 X-ray and gamma-ray dosimetry 79 Cavity chambers 79 Photographic dosimetry 79 Solid state dosimetry 79 IV Highlights of the research program-—Continued 2.1. Physics, electronics, and measurement standards—Continued 2.1.7. Radiation physics—Continued Response of silicon charged particle detectors at low temper- Page atures 80 Radioactive sources 80 Scattered spectrum of water-shielded sources 80 Standards of radioactivity 80 Radiation interaction with matter 82 Radiation interaction with nuclei 82 The interaction of bremsstrahlung with alined nuclei 82 Nuclear matter distributions as determined from neutral meson photoproduction 82 Neutron time-of-flight techniques . 84 Particle interaction theory 85 Preparations for new linear accelerator 85 Linear accelerator theory 85 Heavy-ion source for magnet-optic studies 86 High-current beam-handling problems 86 Equipment for use with Linac 86 Data-logging and data-handling system for the linear accelerator 86 2.1.8. Laboratory astrophysics 87 Physics of atomic collisions 88 Astrophysics 89 Resonance physics 89 Plasma physics, statistical physics, and aerodynamics 90 Data center on atomic collision cross sections 90 2.2. Chemistry and properties of materials 90 2.2.1. Analytical and inorganic chemistry 90 Atomic weight redetermination 91 Reactivity of coordination compounds 91 Thermodynamics of aqueous solutions 91 pH scale for alcohol-water solvents 91 Dielectric cryometry for determining purity 92 Argon shielding in spectrochemical analysis 92 Transition probabilities 93 Laser microprobe 93 Solvent effects on the rates of acid-catalyzed reactions 94 Acidities of dinitrophenols in benzene and water 94 Crystal growth from mixed solvents 94 Studies of crystal symmetry 95 X-ray analysis of crystalline solids 95 Control of fractional distillation 96 Moisture determination 96 2.2.2. Physical chemistry 96 Thermochemistry 97 Kinetics of ion decomposition 97 Field emission / 97 High-temperature microwave spectroscopy 97 Enolization and isomerization reactions of reducing sugars ... 98 Cryogenic surface chemistry 99 Kinetic isotope effects 99 Shock-wave studies of unimolecular reactions 99 Ionization processes at surfaces 100 Polycyclic ketones 100 Vacuum ultraviolet photochemistry 101 High-temperature surface reactions 101 Radiolysis of simple hydrocarbons ; 101 Standard reference data in physical chemistry 102 2.2.3. Inorganic solids 102 Rare gas crystals 102 Molar volume of solid neon isotopes 103 Crystalline forms of bismuth oxide 103 Random network models for liquid and glass studies 104 Vapor-pressure studies 105 Crystal structure determinations 105 Phase change studies of silica-metal oxide systems 105 Standard glasses for viscosity measurements 106 Elastic constant data 106 V 2. Highlights of the research program—Continued 2.2. Chemistry and properties of materials—Continued Page 2.2.3. Inorganic solids—Continued Structural studies of materials under high pressures 106 Mechanical properties of ceramic bodies 108 2.2.4. Metallurgy 108 Metal fatigue investigated in aluminum alloys 109 Properties of metals at elevated temperatures 109 Gage block materials demonstrate desired stability 110 Deformation of metals studied at low temperatures 110 Slack-quenching technique developed 110 Stress corrosion of carbon steels Ill Effect of applied current on aluminum corrosion Ill Corrosion reactions studied at metal
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