Reported here is the progress on the Development of Biological Coal Gasification for DOE contract No. DE-AC21-90MC27226 MOD A006. Task 1, NEPA Compliance and Updated Test Plan has been completed. Progress toward Task 2, Enhanced Methane Production, is reported in the areas of bacterial strain improvement, addition of co-substrates, and low cost nutrient amendment. Conclusions reached as a result of this work are presented. Plans for future work are briefly outlined.

Single crystal silicon has been the material of choice for x-ray monochromators for the past several decades. However, the need for suitable monochromators to handle the high heat load of the next generation synchrotron x-ray beams on the one hand and the rapid and on-going advances in synthetic diamond technology on the other make a compelling case for the consideration of a diamond monochromator system. In this paper, we consider various aspects, advantages and disadvantages, and promises and pitfalls of such a system and evaluate the comparative performance of a diamond monochromator subjected to the high heat load of the most powerful x-ray beam that will become available in the next few years. The results of experiments performed to evaluate the diffraction properties of a currently available synthetic single crystal diamond are also presented. Fabrication of a diamond-based monochromator is within present technical means.

In earlier reports we have describe d our efforts to understand the mechanism of deuterium incorporation during the thermolysis of 1,2-diphenylethane and 2,2,5,5-tetramethyl-3,4-diphenylhexane under D[sub 2] gas in a glass vessel. We have reported that in both of these cases, there is substantial deuterium incorporation. A summary of our conclusions follows: Conclusions previously reported for the 1,2-diphenylethane (DPE) system. 1. Benzyl radicals produced in the thermolysis react mainly with DPE to extract a hydrogen atom and produce undeuterated toluene. 2. The 1,2-diphenylethyl radicals produced are mainly responsible for the reaction with D[sub 2] to give D atoms. 3. D atoms then react with aromatic rings to form adduct radicals which are, at least in part, reconverted to D-substituted aromatics in termination steps. 4.2-Phenylethyl radicals react in a less discriminating manner, 1/3 to 1/2 of the events probably involving direct reaction with D[sub 2]. 5. A reasonable match to major product distribution can be accomplished using a model consisting of the set of ten reactions.

In earlier reports we have describe d our efforts to understand the mechanism of deuterium incorporation during the thermolysis of 1,2-diphenylethane and 2,2,5,5-tetramethyl-3,4-diphenylhexane under D{sub 2} gas in a glass vessel. We have reported that in both of these cases, there is substantial deuterium incorporation. A summary of our conclusions follows: Conclusions previously reported for the 1,2-diphenylethane (DPE) system. 1. Benzyl radicals produced in the thermolysis react mainly with DPE to extract a hydrogen atom and produce undeuterated toluene. 2. The 1,2-diphenylethyl radicals produced are mainly responsible for the reaction with D{sub 2} to give D atoms. 3. D atoms then react with aromatic rings to form adduct radicals which are, at least in part, reconverted to D-substituted aromatics in termination steps. 4.2-Phenylethyl radicals react in a less discriminating manner, 1/3 to 1/2 of the events probably involving direct reaction with D{sub 2}. 5. A reasonable match to major product distribution can be accomplished using a model consisting of the set of ten reactions.

The purpose of this three year study is to develop a neutron focusing system to be used with the Texas Cold Neutron Source (TCNS) to produce an intense beam of neutrons. A prompt gamma activation analysis (PGAA) facility will also be designed, setup, and tested under this DOE grant. During the first year of the DOE grant, a new procedure was developed and used to design a focusing converging guide consisting of truncated rectangular cone sections. Detailed calculations were performed using a 3-D Monte Carlo code which the authors wrote to trace neutrons through the existing curved guide of the TCNS into the proposed converging guide. Using realistic reflectivities for Ni-Ti supermirrors, they obtained gains of 4 to 5 for the neutron flux averaged over an area of 1 x 1 cm. Two graduate students were supported by the first year of the DOE grant. Both have passed the Nuclear Engineering qualifying examination and have been admitted to candidacy for the doctoral degree at The University of Texas at Austin. Their programs of study and dissertation projects have been approved by the appropriate committees.