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Annual Report 1955 National Bureau of Standards U. S. Department of Commerce UNITED STATES DEPARTMENT OF COMMERCE Sinclair Weeks, Secretary NATIONAL BUREAU OF STANDARDS A. V. Astin, Director Annual Report 1955 National Bureau of Standards Miscellaneous Publication 217 For sale by the Superintendent of Documents, U. S. Government Printing Office Washington 25, D. C. - Price 55 cents Contents Page General Review 1 1.1. Introduction 1 1.2. Technical Activities 2 1.3. Administrative Activities 9 1.4. Publications 11 Research and Development Program 12 2.1. Electricity and Electronics 12 Fundamental electrical units 13, Electrochemistry 14, Improve- ments in measuring techniques 14, Resistor noise 15, Electron tubes 15, Research on electric spark discharge 16, Pole-top failure 16, Design of mutual inductance transducers 16, Marine weather station 16, Special electronic devices 17, Preferred circuits 17, Mechanized production of electronics 18. 2.2. Optics and Metrology 19 Intercomparison of standards 20, Determination of color dif- ferences 20, Glass color standards 21, Spectacle lenses 22, Aviation lighting 23, Refractometry of synthetic crystals 24. 2.3. Heat and Power 24 Temperature standards 25, Low-temperature research 26, Properties of air and related substances 28, Thermodynamic properties of metals and salts 29, Mechanical degradation of polymers 29, Combustion in engines 30. 2.4. Atomic and Radiation Physics 31 Velocity of light redetermined 31, Radiation balance 32, X-ray calorimeter 32, Electron beam extractor 33, New radiochem- istry laboratory 33, Attenuation of gamma rays at oblique incidence 34, Zone melting apparatus 35, International inter- comparison of radiation standards 36, Negative ion research 36. 2.5. Chemistry 37 Colloidal dispersions 37, Titanium compounds 38, Labeled sugars 38, Research in analytical chemistry 39, Electrodeposi- tion of metals from organic solutions and fused salts 40, Advances in physical chemistry 41, Evaluation of scientific data 42, Special investigations and devices 42. iii .6. Mechanics . t Measurement of hearing 44, Jet noise 44, Architectural acoustics 44, Measurement on material substances with sound 45, Analysis of sound 45, Measurement of high pressures 46, Aerological and flight test instruments 47, Water-wave research 47, Density current research 48, Boundary layer transition 48, Surface roughness 49, Vibration standards for the calibration of pickups 50, Thermal stresses 51, Fatigue strength of aircraft structures 51, Airplane design 52, One thousand-pound balance 53, Densities of alcohol-water mix- tures 54, Combustion in high-velocity air 54, Fuel accessories for aircraft 54. .7. Organic and Fibrous Materials Crystallization phenomena in polymers 55, Behavior of "pure gum" rubber vulcanizates in tension 56, Effect of atmospheric contaminants on textiles 57, Effect of light on coated ground- wood papers 57, Accelerated aging of record papers 58, Amino acid analysis of collagen 58, Micropore structure of leather 59, Temperature of tires 60, High-temperature polymers 60, Blood plasma expanders 61, Dielectric studies 62, Multiaxial stretching of plastic glazing material 62, Infrared spectra of insoluble organic materials 62, Mechanism of rain erosion 63, Panographic dental X-ray machine 64, Gallium alloys 65. .8. Metallurgy Constitution diagrams 65, Properties and behavior ot alloys 66, Mechanisms of the deformation of metals 67, Titanium 69, Fatigue of metals 69, Corrosion 70. .9. Mineral Products Thermal decomposition of crystalline materials 72, Structure and properties of glass 72, Ceramic transducers 73, Ceramics containing uranium dioxide 73, Mechanism of deformation in ceramics 74, Electrical conductance in vitreous ceramics 75, Thermochemistry of inorganic materials 75, Crystal structure of the phosphates 76, Standard X-ray diffraction patterns 76, Phase studies of the system lime-silica-water 76, High-tem- perature, ceramic-metal strain gages 77, Phase equilibrium studies on portland cement 77, Effect of ceramic coatings on the creep of alloys 78, Reaction of portland cement with car- bon dioxide 79, Refractory concrete for jet aircraft aprons 79, Properties of glass fibers 80, Special optical glasses 80. Page 2.10. Building Technology 81 Instrumentation and measurement 82, Control of cracking in reinforced concrete 82, Flame spread test method 83, Aircraft fire detection 84, Water usage for drinking water coolers 84, Effect of moisture on rcof deck insulation 85, Performance of air cleaners 86, A study of a ceiling panel heating system 86, Asphalt roofing 87, Roof maintenance manual 87. 2.11. Applied Mathematics 87 Numerical analysis 88, Digital computation 89, Statistical en- gineering 91, Mathematical physics 92. 2.12. Data Processing Systems 94 SEAC 95, Analog computers 95, Development of new com- puters 96, Computer circuitry packaging 96, Diode amplifier 96, Cold cathode gas diodes 96, Other diode studies 97, Mag- netic core investigations 97, Rotating reading head 97, High- density magnetic tape recording 98. 2.13. Cryogenic Engineering 99 Cryogenic equipment 99, Cryogenic processes 100, Low-tem- perature properties of materials 101, Liquefaction of gases 102. 2.14. Radio Propagation Physics 103 Oblique incidence studies 104, Low-frequency propagation 105, Cosmic noise 105, Arctic radio propagation 106, Interna- tional Geophysical Year 106, Speed of light 107. 2.15. Radio Propagation Engineering 107 Radio noise studies and noise predictions 108, Tropospheric forward scatter propagation 109, Phase stability of VHF and UHF transmissions 110, Obstacle enhancement of signals 110. 2.16. Radio Standards 110 Power measurements 111, Voltage standards 111, Attenuation standards 112, Coaxial resonance line for microwave imped- ance measurements 112, Precision microwave interferometer 112, Dielectric and magnetic materials 113, Microwave spectroscopy of gases at high pressure 114, Atomic standards of frequency and time 115, Frequency standards and stand- ard frequency broadcasts 115. 2.17. Basic Instrumentation 117 Specific instrument developments 118, Instrument reference service 119, Indexing system 120, Instrument surveys 121, Studies on shock and vibration 121. V Page 3. Calibration, Testing, and Standard Samples 122 3.1. Calibration Center 123 3.2. Making Standards Available for Practical Use 123 Time and frequency 123, Clinical thermometers 124, Dental materials 126. 3.3. Calibration Requests Show Industry Trends 126 3.4. New Standard Samples 127 3.5. Testing for Government Purchase 128 3.6. Services in Other Areas 130 4. Cooperative Activities 132 Federal specifications 133, Methods of test 134, Industry spec- ifications 134, Building and safety codes 135, Radiation pro- tection 136, Weights and measures 136, Research associate program 137, Optics 139, Heat and power 140, Building tech- nology 140, Data processing 141, Radio propagation 142, Dental materials 144, Metals, mineral products, and other materials 144, Acoustics 145, Smog 146, Highway truck weighing 146, Educational program 146, International 147. 5. Appendices 149 5.1. Organization 149 5.2. Fiscal Data on NBS Program 154 5.3. Advisory Committees 155 5.4. Awards and Honors 157 5.5. List of Publications 158 vi 1. General Review 1.1. Introduction During the past year, the major effort of the National Bureau of Standards has been devoted to the strengthening of its basic programs. With the assistance of scientific advisory committees, the Bureau is seeking: to develop a balanced technical program bv increasing the level of research, especially basic research, in those fields for which the Bureau has an assigned responsibility. An effective standards research program must at all times remain at the forefront of science. It must continually push to the frontiers in order to provide the new standards needed bv scientists in their studies of new materials and newly understood phenomena. Standards are important to scientific inquiry. They are the results of meticulous investigation themselves. They are intimately associated with the basic units of measurement or comparison by which experiments may be properly described and verified. Research associated with the development of standards helps to unravel some of the puzzling results obtained with new experiments and leads scientists and engineers to the best avenues for the solution of their special technical problems. Thus, it pro- vides clues for effective applied research and helps to eliminate false starts in development work. By virtue of its responsibility for the custody, maintenance, and establishment of the Nation's primary standards of physical measurement, the National Bureau of Standards serves Govern- ment, science, and industry. The Bureau is the source for physical standards used in mass production and in the development of interchangeable parts—so vital to our modern economy. For industry and science, the Bureau also performs critical calibrations of working standards and distributes standard samples for use in production and research. For Government, the Bureau develops methods for the acceptance testing of materials in procurement and helps to devise codes and specifications. In addition, the scientific staff of the Bureau provides technical advice to various scientific and Government groups and undertakes a large variety of studies to meet the special needs of other Government agencies. Obviously, the work of the National Bureau of Standards is quite broad. The scope of this responsibility is such that the Bureau I must continually adjust
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