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The objective of this project has been to demonstrate the efficacy of cryogenic core technology as an integrated approach to sample collection and handling for use as a tool for monitoring subsurface remediation. This has included the development of a in situ cryogenic coring system, the evaluation of molecular biological tools (MBTs) analysis in conjunction with that system and the demonstration that the cryogenic sampling protocols are robust and ready for application by the remediation user community. In addition, cryogenic sample handling has allowed development of a new approach to directly determine local degradation activity using the ratio of labile mRNA to stable DNA for target genes., The original document contains color images.

Je zkoumána plazmochemie methylphenylsilanu zředěného vodíkem v radiofrekvenčních výbojích při depozici tenkých vrstev plazmatických polysilanů. Reakční systém byl studován za podmínek vedoucích k nejlepším materiálům za podmínek identifikovanžch v dřívějších studiích. MS je využita ke sledování fragmentace monomeru a k přímé dynamické i statické chrakterizaci výboje. Je popsán efekt příkonu buzení plazmatu. Produkty plazmaticky indukované reakce se sbíraly do kryogenní pasti a následně byly separovány pomocí GC MS. Byly identifikovány organicko-křemíkové prekurzory plazmatické polymerizace jednodimenzionálních polysilanů. Byla zavedena jednoduchá metoda stanovení konverze monomeru., The plasmochemistry of methylphenylsilane diluted with hydrogen in radio frequency discharges during the deposition of thin films of plasmatic polysilane is investigated. The plasma reaction system has been examined under conditions identified from previous studies to give the best material. Mass spectrometry is used to follow the monomer fragmentation and to directly (on-line) analyze the plasma composition under the static and dynamic regimes. The effect of input power is described. The products of the plasma-induced reactions are collected in a cryogenic trap and then separated and analyzed by gas chromatography with a mass spectrometry analyzer. Organosilicon precursors for the plasma polymerization of one-dimensional polysilanes are identified together with prevailing reaction pathways in the plasma. A simple method of monomer conversion efficiency is introduced.

Three methods for removing trace contaminants from stainless-steel sampling cylinders were evaluated: evacuation, helium flushing, and steam flushing. Background and postcleaning concentrations were ascertained by gas chromatographic analyses for four hydrocarbons. From these data, washout curves were generated showing that steam flushing was the most effective method for the worst-case conditions.