This report presents all analytical data on the aluminum phosphate zone on lands owned by the American Agricultural Chemical Co. (A. A. C. Co.), and is one of a series of reports on lands of the companies active in the Land-Pebble Phosphate district.

Photogeologic map of Kanab SE, Utah, Kane County

Objective is the development of nuclear magnetic resonance imaging techniques and technology applicable to the nondestructive characterization of green-state ceramics. To this end, a three-dimensional (3-D) NMR imaging technique has been developed, based on a back-projection acquisition protocol in combination with image reconstruction techniques that are based on 3-D Radon transform inversion. The method incorporates the experimental flexibility to overcome many of the difficulties associated with imaging of solid and semisolid broad-line materials, and also provides contiguously sampled data in three dimensions. This technique has been evaluated as a nondestructive characterization method for determining the spatial distribution of organic additives in green-state injection-molded cylindrical Si₃N₄ tensile specimens. The technique has been evaluated on the basis of providing moderate image resolution over large sample volumes, high resolution over smaller specimen volumes, and sensitivity to variations in the concentration of organics. Resolution of 200 micrometers has been obtained with excellent sensitivity to concentration. A detailed account of the 3-D imaging results obtained from the study, a discussion of the difficulties and limitations of the imaging technique, and suggestions for technique and system improvements are included.

PCN is a system for developing and executing parallel programs. It comprises a high-level programming language, a set of tools for developing and debugging programs in this language, and interfaces to Fortran and C that allow the reuse of existing code in multilingual parallel programs. Programs developed using PCN are portable across many different workstations, networks, and parallel computers. This document provides all the information required to develop parallel programs with the PCN programming system. It includes both tutorial and reference material. It also presents the basic concepts that underlie PCN, particularly where these are likely to be unfamiliar to the reader, and provides pointers to other documentation on the PCN language, programming techniques, and tools.

Gravimetric changes in marble and limestone briquettes exposed to outdoor environment at five sites in the eastern United States have been monitored since 1984. An earlier report describes procedures and results obtained in 1984--1988. This report presents the results of the exposure period 1984--1988 and reviews and summarizes those of prior years. A linear relationship was found between cumulative gravimetric losses and exposure period or rain depth. These losses resulted in an average recession rate of 14 to 24 {mu}m/yr for marble and twice that for limestone. Variations in recession among the various exposure sites can be ascribed to differences in rain depth and hydrogen ion concentration. The annual recession rates obtained from gravimetry yielded rates that were for marble twice those obtained from runoff experiments, and more than three times those for limestone; this indicates that physical erosion plays an important role. Gravimetric monitoring of exposed briquettes is continuing in a planned 10-yr program.

From introduction: The major objectives of the study are to collect new data to quantify sediment sources, sinks, and transport characteristics, review historical data to quantify and interpret past shoreline changes, perform computer modelling of coastal processes, and provide public coordination and data management.