1970 marked the seventh return of the Cryogenic Engineering Conference, now affiliated with the National Academy of Sciences through the Division of Engineering, National Research Council, to Boulder, Colorado. Local arrangements for this year's meeting have again been capably handled by the University of Colorado and the Cryogenics Division, NBS Institute for Basic Standards. The Cryogenic Engineering Conference Committee gratefully acknowledges the assistance of these two organizations, and particularly the Bureau of Continuation Education of the University of Colorado, for serving as hosts to the 1970 Cryogenic Engineering Conference. The National Academy of Sciences is a private, honorary organization of more than 700 scientists and engineers elected on the basis of outstanding con tributions to knowledge. Established by a Congressional Act of Incorporation signed by Abraham Lincoln on March 3, 1863, and supported by private and public funds, the Academy works to further science and its use for the general welfare by bringing together the most qualified individuals to deal with scientific and tech nological problems of broad significance. Under the terms of its Congressional charter, the Academy is also called upon to act as an official-yet independent adviser to the Federal Government in any matter of science and technology. This provision accounts for the close ties that have always existed between the Academy and the Government, although the Academy is not a governmental agency and its activities are not limited to those on behalf of the Government.

Inhalt
Applied Superconductivity.- A-1 Applications of Superconductivity and Cryogenics in Electric Power Systems.- A-2 British Developments in Superconductivity Applications.- A-3 Superconductivity in High-Energy Physics.- Solid Properties.- B-1 Tensile Properties and Notch Toughness of Some 7XXX Alloys at -452°F.- B-2 Low-Temperature Tensile Properties of Polyethylene Terephthalate Multifiber Yarn and Polystyrene Foam.- B-3 Magnetic Properties of Commercial Soft Magnetic Alloys at Cryogenic Temperatures.- B-4 The Glass Temperature and the Specific Heat of Apiezon N and T Grease.- Thermodynamic Properties.- C-1 New Equation of State for Methane and Propane from Study of Isochoric Data and Multiproperty Analysis.- C-2 Calculation of Thermofunctions of Fluorine.- C-3 NTWOA Nitrogen-Properties Package.- C-4 Phase Equilibria of the Helium-Nitrogen System from 122 to 126°K.- C-5 A Comparison of Rate Expressions for the Low-Temperature Para-orthohydrogen Shift.- Low-Temperature Insulation.- D-1 Advances in Thermal Insulation.- D-2 Experimental Study of a New PVC Foam Insulation System for Liquid-Hydrogen-Liquid-Oxygen Space Vehicles.- D-3 High-Performance Spray-Foam Insulation for Application on Saturn S-II Stage.- D-4 Open-Cell Cryogenic Insulation.- D-5 Experimental Investigation of Lateral Heat Transfer in Cryogenic Multilayer Insulation.- D-6 A Temperature-Decay Method for Determining Superinsulation Conductivity.- Low-Temperature Refrigeration.- E-1 Large-Scale Refrigeration Systems for the Temperature Range 1.0 to 1.85°K.- E-2 Helium-II Refrigerator for 300 W at 1.8°K.- E-3 Hydraulically Operated Two-Phase Helium Expansion Engine.- E-4 Triple-Expansion Stirling-Cycle Refrigerator.- E-5 A Miniature, Vibration-Free, Rhombic-Drive, Stirling-Cycle Cooler.- E-6 A ModifiedSolvay-Cycle Cryogenic Refrigerator.- E-7 A Miniature Self-Regulating Rapid-Cooling Joule-Thomson Cryostat.- E-8 Closed-Cycle Refrigeration for an Airborne Illuminator.- E-9 A Heat-Balance Analysis of a Gifford-McMahon Cryorefrigerator.- Low-Temperature Instrumentation.- F-1 Instrumentation for Storage and Transfer of Hydrogen Slush.- F-2 Microwave Methods for Cryogenic Liquid and Slush Instrumentation.- F-3 Fluid-Phase and Temperature Measurement with a Single Sensor. II.- F-4 Capacitive-Thermometry Characteristics of a Titanate Glass-Ceramic at Low Temperatures.- F-5 The Pressure Distribution in a Liquid-Nitrogen Cold Trap.- Low-Temperature Equipment.- G-1 A Superfluid Plug for Space.- G-2 Application of a Superfluid Valve in a Variable-Temperature Dewar.- G-3 A Magnetically Operated Cryogenic Valve.- G-4 Residual Gas Conduction Near Liquid-Helium Temperatures.- G-5 A New Criterion for the Design of Gas-Cooled Cryogenic Current Leads.- G-6 A Continuous-Distillation Apparatus for the Separation of He3 from He4.- Regenerative Heat Exchange.- H-1 Analytical and Experimental Studies of Compact Wire-Screen Heat Exchangers.- H-2 The Design of Thermal Regenerators for Stirling-Type Refrigerators.- H-3 Heat-Transfer and Flow-Friction Characteristics of Dense-Mesh Wire-Screen Stirling-Cycle Regenerators.- H-4 Performance of Regenerators at Low Temperatures.- H-5 Shuttle Heat Transfer.- Heat Transfer in Helium.- I1 Heat Transfer from Horizontal Cylinders to a Saturated Helium-I Bath.- I2 Nucleate Boiling of Liquid Helium I on Gallium Single Crystals.- I3 Supercritical Helium Cooling of Hollow Superconductors.- I-4 Discrepancies in Critical-Heat-Flux Data Obtained Using Thin-Wire Heaters in Saturated Liquid Helium II.- I5 High-Speed Motion-Picture Studies of FilmBoiling in Liquid Helium II.- I6 Near-Isothermal Dissipative Flow of Liquid He II at Supercritical Velocities.- Film-Boiling Heat Transfer.- J-1 A Study of Film Boiling of Corresponding-States Fluids over a Wide Pressure Range with Cylindrical Heaters.- J-2 Film-Pool Boiling of Nitrogen from Flat Surfaces.- J-3 Experimental Effects of Pressure, Subcooling, and Diameter on Thin-Wire Film Boiling of Liquid Nitrogen.- J-4 Influence of Swirl Flow on Heat Transfer to Nitrogen in Dispersed-Flow Film Boiling.- J-5 Buoyancy Effects on Liquid-Nitrogen Film Boiling in Vertical Flow.- J-6 Anomalous Behavior of Liquid-Nitrogen Drops in Film Boiling.- J-7 Liquid or Solid on Liquid in Leidenfrost Film Boiling.- Heat Transfer.- K-1 Total Normal Emittances of Some Real Surfaces at Cryogenic Temperatures.- K-2 Measurements of Film-Condensation Heat Transfer on Vertical Tubes for Nitrogen, Hydrogen, and Deuterium.- K-3 Design of Water-to-Cryogenic Heat Exchangers with Variable-Thickness Ice Films.- K-4 Vibration Effects on Convective Heat Transfer in a Cryogen-Filled Enclosure.- Indexes.- Author Index.