A Unified and Mechanistic Approach to Creep-Fatigue Damage (open access)

A Unified and Mechanistic Approach to Creep-Fatigue Damage

A new creep-fatigue equation is proposed that takes into account both plastic strain and strain rate. The coefficients and exponents in the damage-rate equation are interpreted by means of the various damage mechanisms of the material. The damage-rate equation has been integrated to analyze various phenomena such as the effects of plastic strain rate on monotonic tensile or creep rupture time, rising mean strain on the low-cycle fatigue behavior at elevated temperature, tensile and compressive hold times on the low-cycle fatigue life at elevated temperature, and cyclic creep. The proposed approach has been successfully applied to elevated-temperature data generated at Argonne National Laboratory and elsewhere for Type 304 austenitic stainless steel under various monotonic and cyclic-loading conditions.
Date: January 1976
Creator: Majumdar, S. & Maiya, P. S.
System: The UNT Digital Library
Multicomponent Isotopic Separation and Recirculation Analysis (open access)

Multicomponent Isotopic Separation and Recirculation Analysis

A digital computer program for design of multi-component distillation columns has been developed based on an exact method of solution of the governing equations. Although this computer program was developed for enrichment of the spent fuels from presently conceived Tokamak-type fusion power reactors by cryogenic distillation, the program can be used for the design of any multi-component distillation column, provided, of course, the necessary thermodynamic and phase equilibrium data are available. To prove the versatility of the computer program, parametric investigations to study the effect of design and operating variables on the composition of the product streams was carried out for the case of separating hydrogen isotopes. The computer program is very efficient; hence, a number of parametric investigations can be carried out with limited resources. The program does, however, require a fairly large computer storage space (approximately 250 K bytes).
Date: January 1976
Creator: Misra, B. & Maroni, V. A.
System: The UNT Digital Library
Hydrologic Characteristics of Lagoons at San Juan, Puerto Rico, During a Januray 1974 Tidal Cycle (open access)

Hydrologic Characteristics of Lagoons at San Juan, Puerto Rico, During a Januray 1974 Tidal Cycle

From introduction: This report presents observed data on the interlagoon and ocean exchange of the flows of water, sediment, and selected chemicals for a tidal cycle in January 1974.
Date: January 1976
Creator: Ellis, S. R. & Gómez-Gómez, F.
System: The UNT Digital Library
Floods in New York, 1972, with Special Reference to Tropical Storm Agnes (open access)

Floods in New York, 1972, with Special Reference to Tropical Storm Agnes

From introduction: Flooding and flood damage in New York during the calendar year 1972 are summarized in this report. The report was prepared at the request of the New York State Department of Transportation under provisions of an agreement between the department and the U.S. Geological Survey for a cooperative, statewide program to investigate the water resources of the State.
Date: January 1976
Creator: Robison, F. Luman
System: The UNT Digital Library
Measurement and Prediction of Sediment Yields in Wisconsin Streams (open access)

Measurement and Prediction of Sediment Yields in Wisconsin Streams

From introduction: This report presents practical and useful sediment-yield information for Wisconsin. Measured and estimated sediment yields are supplemented by information on suspended-sediment concentration and particle size of suspended and bed material for 84 sites in the State. To expand the usefulness of these data, an additional section in the report presents a method to estimate or predict sediment yields in ungaged streams.
Date: January 1976
Creator: Hindall, S. M.
System: The UNT Digital Library
Preliminary Digital Model of Ground-Water Flow in the Madison Group, Powder River Basin and Adjacent Areas, Wyoming, Montana, South Dakota, North Dakota, and Nebraska (open access)

Preliminary Digital Model of Ground-Water Flow in the Madison Group, Powder River Basin and Adjacent Areas, Wyoming, Montana, South Dakota, North Dakota, and Nebraska

Abstract: A digital simulation model was used to analyze regional ground-water flow in the Madison Group aquifer in the Powder River Basin and adjacent areas. Most recharge to the aquifer originates in or near the outcrop areas of the Madison in the Bighorn Mountains and Black Hills , and most discharge occurs through springs and wells. Results from the model calculations indicate that the total flow through the aquifer in the modeled areas was approximately 200 cubic feet per second (5.7 cubic metres per second). The aquifer can probably sustain increased ground-water withdrawals probably would significantly lower the potentiometric surface in the Madison aquifer in a large part of the basin. The digital model could better predict the effects of withdrawals if more accurate estimates of the storage coefficient, transmissivity, and leakance could be obtained.
Date: January 1976
Creator: Konikow, Leonard F.
System: The UNT Digital Library
Liquid-in-Glass Thermometry (open access)

Liquid-in-Glass Thermometry

Report containing information of general interest to manufacturers and users of liquid-in-glass thermometers. This report supersedes Monograph 90. Instructions explaining how to submit a thermometer to the National Bureau of Standards for calibration are provided, and the techniques and equipment, such as stirred liquid comparison baths, used in the calibration procedures are described. A discussion of important principles of acceptable thermometer design and factors affecting their use is included. Listed are tables of tolerances reflecting good manufacturing practices and reasonably attainable accuracies expected with liquid-in-glass thermometers. The calculation of corrections for the temperature of the emergent stem is given in detail for various types of thermometers and conditions of use.
Date: January 1976
Creator: Wise, Jacquelyn A.
System: The UNT Digital Library