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Adhesion of Diamond Films on Tungsten

Description: The U.S. Bureau of Mines has investigated the chemical vapor deposition of diamond films on tungsten substrates. The effects of deposition parameters on the adhesion of the films was determined. The films were produced using a hot filament chemical vapor deposition system. Parameters investigated were substrate temperature and methane concentration in the feed gas. Film quality, morphology, and composition were characterized by scanning electron microscopy and Raman spectroscopy. Adhesion testing was performed using an indentation technique, and the results were quantified by relating adhesion to interface fracture toughness. Diamond films with well-faceted crystalline morphology with grain size greater than 1 pm had poor adhesion properties regardless of substrate temperature or methane concentration. Diamond films with smooth morphologies consisting of rounded clusters of small (<0.2 pm) diamond crystallites and amorphous carbon phases displayed much higher adhesion, although the conditions that led to the growth of these films are not understood.
Date: 1995
Creator: Maggs, K. J.; Walkiewicz, J. W. & Clark, A. E.

Analyses of Alaska Coals

Description: Report issued by the Bureau of Mines discussing the coal fields of Alaska. Analyses of the Alaskan coal fields are presented in detail. This report includes tables, and a map.
Date: 1946
Creator: Gates, George O. & Fieldner, Arno Carl

Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910: Part 1. -- Analyses

Description: From Significance and value of Analyses of Coal: "The analyses published in this report cover samples of coal collected in many different parts of the country with unusual care by experiences men, in such manner as to make them representative of extensive beds of coal."
Date: 1913
Creator: Lord, N. W.

Analyses of Coals in the United States with Descriptions of Mine and Field Samples Collected between July 1, 1904 and June 30, 1910 Part 2. Descriptions of Samples

Description: From Introduction: "This volume contains the descriptions of the samples whose analyses are published in the preceding volume, Part I of this bulletin. The descriptions have been compiled from the notebooks of the persons who collected the samples, have been condensed from accounts given in published reports of the United States Geological Survey, or have furnished by the collection themselves. Inasmuch as the descriptions represent the work of many persons during a period of six years, and inasmuch as they were recorded under widely differing conditions, they necessarily vary in fullness detail."
Date: 1913
Creator: Lord, N. W.

Analyses of Complex Mixtures of Gases: Application to Control and Extinguish Fires and to Prevent Explosions in Mines, Tunnels, and Hazardous Industrial Processes

Description: From Purpose of Report: "The purpose of the report is to point out what the mine-management official, the safety engineer, and the chemist, can do to utilize analyses of complex gas mixtures as basis for safe procedure to (1) control and extinguish fires in mines, tunnels, and individual plants and (2) prevent explosions when dealing with explosive mixtures and sources of ignition. The report is designed to meet the needs of those desiring to utilize analyses of complex-gas mixtures for the above-mentioned purpose."
Date: 1948
Creator: Ash, S. H. & Felegy, E. W.

Analyses of Kentucky Coals

Description: Report issued by the Bureau of Mines discussing analyses of the Eastern and Western coal fields in Kentucky. The two coal fields are described in detail. This report includes tables, and illustrations.
Date: 1944
Creator: McFarlan, Arthur C.