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1962 Research Highlights of the National Bureau of Standards -> .70 -7* »• . 1962 RESEARCH HIGHLIGHTS O F T H E NATIONAL BUREAU OF STANDARDS mm?* 3m •oiV/^jJ'.-. >w-.\ 7> - ANNUAL REPORT The major purpose of standards for measurement is to provide a basis to assure the stability and compatibility of measurements from time to time and from place to place. If the accuracies with which measurement standards are known and utilized are less than the corresponding accuracies required in laboratories and on pro- duction lines then problems ensue. Data cannot then be exchanged with optimum confidence, and tests performed on the same mate- rials or devices in different places may be incompatible or uncertain in terms of predicted performance. It is therefore imperative that those responsible for developing, maintaining, and disseminating the measurement standards keep ahead of the important needs of science and industry. Trying to meet this requirement is the dominant and never ending challenge to the National Bureau of Standards. A. V. Astin, Director, NBS. 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 1962 Research Highlights of the National Bureau of Standards Annual Report, Fiscal Year 1962 December 1962 Miscellaneous Publication 246 For sale by the Superintendent of Documents, U.S. Government Printing Office Washington 25, D.C. - Price 70 cents The National Bureau of Standards, Washington, D.C., laboratories (top) and Boulder, Colorado, laboratories (bottom). Contents Page 1. Genera] review 1 Standards and measurement methods 2 Matter and materials 4 Astrophysical and plasma physics research 7 Radio propagation studies 8 Automatic data processing 10 Building research study 11 Measurement services 11 National conference of standards laboratories 13 Cooperative activities 17 International activities 18 Administrative activities 19 Publications 21 2. Highlights of the research program 22 2.1. Physics, electronics, and measurement standards 22 2.1.1. Metrology 22 Photometric units internationally intercompared 23 Slant visibil-ty meter developed 24 Four-filter thermoelectric colorimeter 24 Refractive index measurements extended 24 Fiber optics 25 Luminance standards developed for photographic exposure meters 25 Absolute measurement of sphere diameters 25 Revised length calibration equipment and procedures 26 Glass bead standard samples 26 Gaseous laser for interferometry 26 Gear metrology laboratory established 27 Wave front shearing interferometer 27 Standards of mass and weighing techniques . 28 Surface roughness standards 29 2.1.2. Mechanics 30 Infrasonic waves in the atmosphere and in the earth 31 Elastic changes caused by static loads 31 Acoustical repulsion of birds at airports 32 Reverberation-chamber technique for calibration of standard- type noise sources 32 Field measurements of airborne and impact sound insulation . 33 Pressure measurement 33 Hydrodynamic effect of hydrophobic materials 34 Culvert hydraulics 34 High-temperature impact tests 35 Spectrum fatigue of aircraft structures 36 Strain gage evaluation 36 High-temperature tests of vibration pickups 36 Rheology 36 Hypersonic combustion 37 Fluid metering 37 High-temperature thermocouples 38 Stability tests of a new thermocouple 38 Catalytic effects of thermocouple materials 39 2.1.3. Electricity 39 Absolute measurements 39 Precision measurements at high voltages 40 Rapid calibration of resistance voltage dividers 41 Vicious cycle in storage batteries 41 Electrolytic conductance in porous media 41 Corrosion of single crystals of silver in molten salt 43 Microwave absorption in compressed nondipolar gases 43 Magnetism 43 III 2. Highlights of the research program—Continued 2.1. Physics, electronics, and measurement standards—Continued Page 2.1.4. Radio standards 44 Radio physics 45 United States frequency standard 45 Atomic time scale 45 Ft. Collins radio station 46 Fundamental constants 47 Speed of electromagnetic radiation 47 Fine structure measurements 48 Millimeter waves 48 Coherent light 49 Radio plasma studies 50 Bounded plasma calculations 50 Reaction rate coefficients 50 Plasma waves 51 Particle-plasma interaction 51 Radio and microwave materials 51 Applied mathematics 52 Microwave spectral tables 53 Theoretical physics 53 Circuit standards 54 Low-frequency activities 54 High-frequency activities 55 Microwave activities 57 2.1.5. Heat 59 Analog computer for plasma thermometry go Fluorine combustion calorimetry 61 Gaseous heat transfer at low temperatures 62 Nuclear reactions with oriented nuclei 62 Low-temperature thermometry 62 Steady-state measurements of molecular lifetimes 63 Thermodynamic tables 63 Kinetic theory of dense gases 64 Pair-distribution function in dense gases 65 2.1.6. Atomic physics 65 Laboratory astrophysics 65 Atomic energy levels 65 Transition probabilities 67 Collision cross sections 67 Far ultraviolet radiation physics 68 Infrared spectroscopy of gases 69 Infrared reference standards 69 Electron scattering 69 Biological constant studied 69 Electron optics 69 Solid-state physics 69 Lasers. 71 2.1.7. Radiation physics 71 Radioactivity standards 71 Radiation theory 72 Cross sections 72 Penetration and diffusion 72 Shielding engineering for civil defense 72 Linear accelerator 73 High-energy radiation 74 Ionization dosimetry 74 Large ionization chamber 75 Cavity corrections 75 Scattering measurements 75 Photographic dosimetry 75 Solid-state dosimetry 77 Nucleonic instrumentation 77 Neutron physics 77 Radiation protection recommendations 78 International standards 79 2. Highlights of the research program— Continued Page 2.2. Chemistry and properties of materials 80 2.2.1. Analytical and inorganic chemistry 80 Plutonium standard issued 80 Atomic weight of chlorine 80 Trace level analysis 80 Uranium analysis standard 81 Water determination in commercial products 81 Determining transition probabUities using the gas-stabilized arc 81 X-ray analysis of noble metal alloys 82 Trace element standard samples 82 Test mixture for fractionating columns developed 82 Improvements in liquid-solid chromatography 83 Dielectric constant change 83 X-ray diffraction 84 Internal crystal study 84 Crystal growth 84 2.2.2. Physical chemistry 84 Precision calorimetry 85 Reactions of hydrogen atoms 85 Ionization processes at surfaces 85 Field emission microscopy 86 Conformational anaylsis 87 Isotope effects 87 Higher ketoses 87 Molecular isomerism 87 Low-temperature spectroscopy 88 Collision and ion-decomposition processes 88 Collisional energy transfer 88 Vacuum ultraviolet photochemistry 89 Radiolysis of simple hydrocarbons 90 Isotopic abundance ratio determined 90 Thermodynamic reviews 91 2.2.3. Inorganic solids 91 Y aporization of refractory substances 92 New microbalance required to study refractory substances .... 92 Studies of alumina 92 Plasma torch used in crystal growth 92 Rare gas crystals and vapor '"snakes" 93 Fibrous form found in silica 94 Polymorphic transition at high pressure 94 Properties of silver iodide studied 96 Symmetry of crystals under strain 96 2.2.4. Metallurgy 97 Method developed for slack-quenching steels 97 Metal fatigue phenomenon 97 Gage block stability 98 Stainless steel diagram completed 98 Tensile properties of nickel-aluminum alloy 98 Electronprobe microanalyzer completed 98 Computer produces quantitative metallographic data 99 Standards produced for gas content in metals 99 Corrosion reactions observed on metal surfaces 99 Stress corrosion cracking 99 Polarization measurements used to study corrosion rates 99 Alloying behavior of uranium 100 Ni-Cr alloy resists oil-ash attack 101 Nuclear magnetic resonance. , 101 Soft X-ray spectroscopy utilized 101 Crystal diffusion equations modified 101 Metal crystallization process investigated 102 Physical behavior of metals studied 103 Low-temperature study of metals initiated 103 Electrochemical reactions 103 Hydrogen embrittlement studied 103 Tungsten deposition 103 V 2, Highlights of the research program—Continued 2.2 Chemistry and properties of materials—Continued Page 2.2.5. Polymers 104 Molecular weight distributions of polymers studied 104 Ellipsometry used to measure polymer adsorption 105 Rubber hardness testers compared 105 Apparatus measures thermal expansion of small specimens .... 106 Air drag on fibers under impact 106 Interlaboratory evaluations of test methods 106 Atomic radiation affects polystyrene aiid cellulose 107 Thermal decomposition of polystyrene * 107 Fluorescence of cellulosic polymers 107 Viscoelastic behavior of rubbers investigated 107 Color phenomena observed in polymer fracture 108 Ethylene-propylene copolymers studied 108 Polymer degradation 109 Wearing quality of U.S. currency determined 109 Fluoropolyiners synthesized 109 Nonrubber consilituenls of natural rubber identified 110 Free radicals in small molecules 110 Light-scattering phenomena studied in solutions 110 Configurational distributions in polymer chains Ill Conformational changes in peptide-containing polymers 112 Kinetics of collagen precipitation H2 Mercury-tin system investigated 112 2.3. Special technical service programs 113 2.3.1. Applied mathematics 113 Asymptotic expansions 113 Matrix and determinant theory 114 Numerical experimentation 114 Machine translation 114 Mathematical tables 114 Digital computation 115 Statistical engineering 116 Probability and mathematical statistics 116 Experiment design and consultation 116 Mathematical physics 117 Plasma research 117 Theory of satellite orbits 117 Operations research
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