3,819 research outputs found

    Glacial Processes and Their Relationship to Streamflow Flute Glacier, Alaska

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    Flute Glacier is located at the head of the South Fork of Eagle River, Alaska, about twenty air-miles east northeast of Anchorage. It is a small north-facing glacier, approximately two miles long and half a mile wide, situated in a deep glacial valley (see Figure 1). Elevations on the glacier range from 3,500 feet at the terminous to 5,800 feet at the top of the accumulation area. Water from Flute Glacier becomes the South Fork of Eagle River, draining about 32 square miles of area compared to a 192 square mile drainage basin for Eagle River. Limited discharge measurements made during October 1968 suggest that the South Fork contributes about 20% of the water flowing down Eagle River. Glacial meltwater forms an important percentage of the waters of the Eagle River system. Glaciers feeding the main Eagle River are large, complex and difficult to study. Flute Glacier, relatively small and of simple plan, was selected for study because of its small size and proximity to the metropolitan area of Anchorage. Water from the Eagle River system is presently included in the plans for future water supply for Anchorage. The Eagle River valley up to the 500 ft contour is a federal power reserve. The climate of the area surrounding Flute Glacier is alpine with cool temperatures and higher than average precipitation for the area. All the glacier is above treeline so no plant life is obvious. Mountain sheep inhabit the sharp alpine peaks surrounding the glacier.The work upon which this report is based was supported by funds (Project A-021- ALAS) provided by the United States Department of the Interior, Office of Water Resources Research, as authorized under the Water Resources Act of 1964 as amended

    Stratigraphy of the Nilsen Plateau, Western Escarpment, Antarctica

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    The University Archives has determined that this item is of continuing value to OSU's history.Field work resulting in this report was conducted in 1963-64. Sixteen sections along approximately 35 miles of escarpment were measured to provide data for this report. About 500 rock samples have been archived at the U.S. Polar Rock Repository at The Ohio State University. Rock sample descriptions and locations have been included with this report. Supporting details for statements made in this paper reside in files maintained by the author. About 2000 feet of sedimentary rocks and at least an equal thickness of diabase dikes and sills rest on an ancient erosion surface, and are divided into five formations. In ascending order these are; Scott Glacier Formation, Roaring Formation, Amundsen Formation, Queen Maud Formation and the Nilsen Formation. The formations are mostly flat–lying, have been altered by heat from numerous diabase intrusions, and are locally displaced by high–angle faults. Non-uniform injection of diabase dikes and sills irregularly displaces sedimentary strata.Office of Polar Programs, National Science Foundatio

    Phase Zero Contracting Operations - Strategic and Integrative Planning for Contingency and Expeditionary Operations

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    Contracting in expeditionary operations is not new. What is new is the scope and magnitude of the roles that contracting and contractors play in today’s military operations. Lack of planning and sound contract integration at the strategic level leads to inefficiencies, ineffectiveness, and, in many cases, outright fraud. Annex W, Operational Contract Support Plan, is the overall operations plan for Geographic Combatant Commands and the Services within the Adaptive Planning and Execution System framework. The authors propose an Integrated Planner and Executor (IPE) model for operational contract support and its integration into Annex W and existing war planning systems by congressionally mandating, authorizing, and funding IPE positions within Service structures. The IPE would be vested with the authority to establish, monitor, and manage Annex W

    Removal of carbamazepine and sulfamethoxazole by MBR under anoxic and aerobic conditions

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    This study reveals for the first time that near-anoxic conditions (dissolved oxygen, DO - 0.5 mg/L) can be a favorable operating regime for the removal of the persistent micropollutant carbamazepine by MBR treatment. The removal efficiencies of carbamazepine and sulfamethoxazole by an MBR were systematically examined and compared under near-anoxic (DO\u27 0.5 mg/L) and aerobic (DO\u3e 2 mg/L) conditions. Preliminary batch tests confirmed that sulfamethoxazole is amenable to both aerobic and anoxic biotransformation. However, carbamazepine-a known persistent compound-showed degradation only under an anoxic environment. In good agreement with the batch tests, during near-anoxic operation, under a high loading of 750 J.l8 /Ld, an exceptionally high removal (68 ± 10%) of carbamazepine was achieved. In contrast, low removal efficiency (12 ± 11%) of carbamazepine was observed during operation under aerobic conditions. On the other hand, an average removal efficiency of 65% of sulfamethoxazole was achieved irrespective of the DO concentrations

    Impact of humic acid fouling on membrane performance and transport of pharmaceutically active compounds in forward osmosis

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    The impact of humic acid fouling on the membrane transport of two pharmaceutically active compounds (PhACs) - namely carbamazepine and sulfamethoxazole - in forward osmosis (FO) was investigated. Deposition of humic acid onto the membrane surface was promoted by the complexation with calcium ions in the feed solution and the increase in ionic strength at the membrane surface due to the reverse transport of NaCl draw solute. The increase in the humic acid deposition on the membrane surface led to a substantial decrease in the membrane salt (NaCl) permeability coefficient but did not result in a significant decrease in the membrane pure water permeability coefficient. As the deposition of humic acid increased, the permeation of carbamazepine and sulfamethoxazole decreased, which correlated well with the decrease in the membrane salt (NaCl) permeability coefficient. It is hypothesized that the hydrated humic acid fouling layer hindered solute diffusion through the membrane pore and enhanced solute rejection by steric hindrance, but not the permeation of water molecules. The membrane water and salt (NaCl) permeability coefficients were fully restored by physical cleaning of the membrane, suggesting that humic acid did not penetrate into the membrane pores

    Water extraction from mixed liquor of an aerobic bioreactor by forward osmosis: membrane fouling and biomass characteristics assessment

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    This study investigated membrane fouling and biomass characteristics during water extraction from mixed liquor of an aerobic bioreactor by a submerged forward osmosis (FO) system. As the sludge concentration in the reactor increased from 0 to 20 g/L, fouling of the FO membrane increased but was much less severe than that of a reference microfiltration membrane. The results also indicate that aeration can be used to effectively control membrane fouling. By increasing the draw solute concentration, as expected, the initial water flux was increased. However, there appears to be a critical water flux above which severe membrane fouling was encountered. A short-term osmotic membrane bioreactor experiment showed build-up of salinity in the bioreactor due to the reverse draw solute transport and inorganic salts rejection by the FO membrane. Salinity build-up in the bioreactor reduced the permeate flux and sludge production, and at the same time, altered the biomass characteristics, leading to more soluble microbial products and less extracellular polymeric substances in the microbial mass. Additionally, the inhibitory effects of the increased salinity on biomass and the high rejection capacity of FO led to the build-up of ammonia and ortho-phosphate in the bioreactor

    The Distance to the Cygnus Loop from Hubble Space Telescope Imaging of the Primary Shock Front

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    We present a Hubble Space Telescope/WFPC2 narrow-band H-alpha image of a region on the northeastern limb of the Cygnus Loop supernova remnant. This location provides a detailed example of where the primary blast wave first encounters the surrounding interstellar medium. The filament structure is seen in exquisite detail in this image, which was obtained primarily as an EARLY ACQuisition image for a follow-up spectroscopic program. We compare the HST image to a digitized version of the POSS-I red plate to measure the proper motion of this filament. By combining this value for the proper motion with previous measurements of the shock velocity at this position we find that the distance to the Cygnus Loop is 440 (+130, -100) pc, considerably smaller than the canonical value of 770 pc. We briefly discuss the ramifications of this new distance estimate for our understanding of this prototypical supernova remnant.Comment: 18 pages, 3 Figures (2 JPEG and one Postscript
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