United States Bureau of Mines Bulletin 649

From Introduction: "The present study was undertaken as the initial phase of the investigation of substituent effects on the carbon shieldings in 6-membered- and 5-membered-ring heterocyclic modules.

Analyses of tipple and delivered samples of coal collected during fiscal year 1985

This Department of Energy (DOE) publication updates a series of Topical Reports (formerly ''Reports of Investigation'') on the quality of coal purchases under specifications for government use. Listed in alphabetical order by state, county, town, and mine are analytical data on the composition and quality of tipple and delivered samples of coal collected during the fiscal year 1985. Tipple samples were collected by certified commercial laboratories in accordance with instructions given by the Analytical Research Branch (ARB), Coal Science Division (CSD). The delivered samples were collected at destination by installation personnel, and all samples were analyzed under the supervision of the DOE-CSD located at the Pittsburgh Energy Technology Center (PETC), Pittsburgh, Pennsylvania, or the US Army General Material and Petroleum Activity Laboratory, located at New Cumberland, Pennsylvania

United States Bureau of Mines Bulletin 640

Report from the U.S. Bureau of mines discussing the use of infared and ultraviolet-visible spectrometry to study the structure of coal and coal extracts

Characterization of vacuum bottoms from the P-99 coal liquefaction unit

A composite sample of vacuum bottoms has been analyzed by structural sensitive techniques applicable to high molecular weight, highly functional coal-derived materials. The utilization and limitations of x-ray diffraction, infrared, high resolution and /sup 13/C-CP/MAS nuclear magnetic resonance, high resolution and field ionization mass spectrometry, and electron spin resonance are discussed. Particular emphasis is given to the characterization of methylene chloride soluble fractions, isolated by a combination of mild extraction and functionality-specific procedures, in terms of heteroatom functionality, molecular weight and carbon number distributions, and mean structural parameters. This nondistillate but soluble material is primarily a complex mixture of high molecular weight polynuclear aromatic and heterocyclic components with short alkyl substituents. The vacuum bottoms are low in phenolic OH functionality compared to typical SRC-II distillates. 9 references, 25 figures, 14 tables