616 research outputs found
Petrologic, Mineralogic, and Ion Exchange Characteristics of the Rome Formation and Pumpkin Valley Shale on the Oak Ridge National Laboratory Reservation, Oak Ridge, Tennessee
Two outcrops of the Rome Formation and lower Conasauga Group, located on the Oak Ridge National Laboratory Reservation were studied with respect to their petrologic, mineralogic, and ion exchange characteristics. Twenty-eight sample pairs (a pair consisted of a fresh and weathered segment) were taken from each outcrop.
The agrillaceous samples were analyzed by x-ray diffraction and the remaining samples by thin section analysis. Using an ammonia electrode, CEC values were determined for all argillaceous samples and selected non-argillaceous samples. Porosity determinations of the fresh segments of the sandstones and siltstones were made, using 100to 12 micron thick petrographic sections.
X-ray analysis established the presence of illite, glauconite, kaolinite, chlorite, biotite, muscovite, quartz, hematite, calcite, dolomite, Kspar, and plagioclase. Quantification of the shales is complicated by the clay minerals, therefore data is strictly qualitative. The presence of randomly interstratified clays, discrete crystallites, or a combination was suggested by a few broad peaks on the diffractograms. The exact nature of these peaks was undeterminable in this study.
For the argillaceous samples, CEC\u27s ranged from 5.52 to 33.61 meq/100g. A few sandstones analyzed generally had values at or below the lowest value of the siltstones. Clay mineral content (by visual estimates) appeared to be directly proportional to CEC values.
Quartz, Kspar, matrix, cement (quartz overgrowths, hematite, calcite), glauconite, plagioclase, muscovite, and biotite were the mineral components of the sandstones and siltstones. Based on modal analysis, the flowoing average composition for all non-argillaceous samples was calculated: quartz-58%, Kspar-20%, matrix-10%, cement-4%, glauconite-3%, plagioclase-2%, muscovite-1%, miscellany-1%, and biotite-trace.
The typical Rome sandstone is mature, well-sorted, subarkosic, and a very fine sandstone to silty sandstone. Sandy siltstones to silty sandstones, which were moderately sorted immature, are the average non-argillaceous unites of the Conasauga.
The porosity of the samples examined can be attributed to four factors: deterioration of glauconitic and micaceous grains, microscopic voids, discontinuous microscopic cracks, and macroscopic fractures. Values ranged from 0-10%. A notable difference was observed in the average porosities between samples from the two outcrops: 0.7% at the Comparative Animal Research Lab and 3.7% at the Fuel Reprocessing Road Outcrop. The slightly higher degree of weathering at the FR location is believed responsible for the sizeable variations.
Samples from the fresh and weathered segments of all lithologies exhibited little or no mineralogical variation.
The data gathered in this investigation provide information concerning the lithologies directly at or adjacent to waste burial sites. From this data, it is possible to assess the potential for the development of an aquifer, should any material seep from the Pumpkin Valley Shale (where some waste is buried) into the Rome Formation. The uppermost portion of the Rome (thick layers of sandstones) is bound above and below by shale layers. In the event of seepage of waste fluid, shales are significantly more effective in removing cations than sandstones, and are fairly impervious. If any fluid does reach the Rome sandstones, it is unlikely that an aquifer would develop, since the sandstones have low absolute porosities, thus suggesting low permeabilities
Redetermination of 2-[4-(2-hydroxyethyl)piperazin-1-ium-1-yl]ethanesulfonate at 100 K
The crystal structure of the title compound (common name HEPES), C8H18N2O4S, has been redetermined at 100 K in order to properly elucidate the protonation state of the HEPES molecule. The piperazine ring has a chair conformation and one of the N atoms in the ring is protonated, which was not previously reported [Gao, Yin, Yang, & Xue (2004). Acta Cryst. E60, o1328–o1329]. The change of protonation state of the nitrogen atom significantly affects the intermolecular interactions in the HEPES crystal. The structure is stabilized by N—H⋯O and O—H⋯O hydrogen bonds and ionic interactions, as the title compound in solid state is a zwitterion. HEPES molecules pack in layers that are held together by ionic and weak interactions, while a hydrogen-bonded network connects the layers
Watershed-Based Planning for Murrells Inlet: Source Assessment of Fecal Bacteria using Volunteer and Shellfish Sanitation Program Data
2014 S.C. Water Resources Conference - Informing Strategic Water Planning to Address Natural Resource, Community and Economic Challenge
Benzene-1,4-dicarboxylic acid–N,N-dimethylacetamide (1/2)
The asymmetric unit of title compound, C8H6O4·2C4H9NO, contains one half-molecule (an inversion centre in P21/n generates the other half of the molecule) of terephthalic acid (TA) and one molecule of N,N-dimethylacetamide (DMAC). The DMAC molecules are linked to TA by strong O—H⋯O hydrogen bonds
Watershed Plan Implementation Challenges for SMS4S in Murrells Inlet
2014 S.C. Water Resources Conference - Informing Strategic Water Planning to Address Natural Resource, Community and Economic Challenge
Influence of Exogenously Supplemented Caffeine on Cell Division, Germination, and Growth of Economically Important Plants
Caffeine is a plant secondary metabolite of antiherbivory, allelopathic, and antibacterial activity. In our previous study, caffeine was shown to be an effective agent toward plant pathogenic bacteria causing high economic losses in crop production worldwide. Current study indicated that growth media supplementation with soil or plant extract did not interfere with antibacterial action of caffeine against Clavibacter michiganensis, Dickeya solani, Pectobacterium atrosepticum, Pectobacterium carotovorum, Pseudomonas syringae, Ralstonia solanacearum, and Xanthomonas campestris. The impact of caffeine on plant cell division, seed germination and growth of economically important plants was evaluated to assess possible applicability of caffeine in plant protection field. Caffeine impaired plant cell division process and inhibited in vitro germination of tomato and lettuce. Regeneration of potato explants was also negatively affected by the addition of caffeine. However, caffeine spraying or watering of tomato, lettuce and cabbage grown in soil did not impair plant development. Although the tested plants accumulated caffeine, its inner quantity was reduced by peeling and/or cooking. According to the results, caffeine warrants additional attention as a useful, natural compound designated for the control of bacterial plant pathogens. Proposed treatment seems promising especially in the case of providing protection for overwinter-stored table potato tubers
Hybrid minimally invasive epicardial and endocardial 3D-mapping-guided cryoablation for symptomatic pre-excitation syndrome after previous four failed catheter ablations
Minimally invasive hybrid approach for the treatment of Wolff Parkinson-White syndrome is seldom. We report a case of minimally invasive no-x-ray 3D-guided epicardial ablation of accessory pathway in a 23-year-old Caucasian sportsman with pre-excitation and very frequent palpitations with documented symptomatic narrow QRS tachycardia and previous 4 failed percutaneous radiofrequency ablations.Małoinwazyjne, hybrydowe podejście do leczenia zespołu Wolff Parkinsona-White’a jest rzadko stosowane. W pracy przedstawiono przypadek małoinwazyjnej, hybrydowej, 3D-mapowanej nasierdziowej ablacji dodatkowej drogi przewodzenia bez zastosowania skopii u 23-letniego kaukaskiego sportowca z cechami preekscytacji, bardzo częstymi kołataniami oraz z udokumentowanym objawowym częstoskurczem z wąskimi zespołami QRS, leczonym czterokrotną nieskuteczną przezskórną ablacją
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