Science.gov

Sample records for actual field site

  1. Meteorological field measurements at potential and actual wind turbine sites

    SciTech Connect

    Renne, D.S.; Sandusky, W.F.; Hadley, D.L.

    1982-09-01

    An overview of experiences gained in a meteorological measurement program conducted at a number of locations around the United States for the purpose of site evaluation for wind energy utilization is provided. The evolution of the measurement program from its inception in 1976 to the present day is discussed. Some of the major accomplishments and areas for improvement are outlined. Some conclusions on research using data from this program are presented.

  2. Field site selection

    NASA Technical Reports Server (NTRS)

    Schwarz, D. E.; Ellefsen, R. E.

    1981-01-01

    Several general guidelines should be kept in mind when considering the selection of field sites for teaching remote sensing fundamentals. Proximity and vantage point are two very practical considerations. Only through viewing a broad enough area to place the site in context can one make efficient use of a site. The effects of inclement weather when selecting sites should be considered. If field work is to be an effective tool to illustrate remote sensing principles, the following criteria are critical: (1) the site must represent the range of class interest; (2) the site must have a theme or add something no other site offers; (3) there should be intrasite variation within the theme; (4) ground resolution and spectral signature distinction should be illustrated; and (5) the sites should not be ordered sequentially.

  3. Stability Tests with Actual Savannah River Site Radioactive Waste

    SciTech Connect

    Walker, D.D.

    2002-09-09

    solutions in two laboratory experiments. The first experiment tested four waste solutions for supersaturation of aluminum by monitoring the aluminum concentration after seeding with gibbsite. The second experiment tested two waste samples for precipitation of aluminosilicates by heating the solutions to accelerate solids formation. The results of the experiments with actual waste solutions are supported in this report.

  4. Photovoltaic performance models: an evaluation with actual field data

    NASA Astrophysics Data System (ADS)

    TamizhMani, Govindasamy; Ishioye, John-Paul; Voropayev, Arseniy; Kang, Yi

    2008-08-01

    Prediction of energy production is crucial to the design and installation of the building integrated photovoltaic systems. This prediction should be attainable based on the commonly available parameters such as system size, orientation and tilt angle. Several commercially available as well as free downloadable software tools exist to predict energy production. Six software models have been evaluated in this study and they are: PV Watts, PVsyst, MAUI, Clean Power Estimator, Solar Advisor Model (SAM) and RETScreen. This evaluation has been done by comparing the monthly, seasonaly and annually predicted data with the actual, field data obtained over a year period on a large number of residential PV systems ranging between 2 and 3 kWdc. All the systems are located in Arizona, within the Phoenix metropolitan area which lies at latitude 33° North, and longitude 112 West, and are all connected to the electrical grid.

  5. A comparison of actual and perceived residential proximity to toxic waste sites.

    PubMed

    Howe, H L

    1988-01-01

    Studies of Memphis and Three Mile Island have noted a positive association between actual residential distance and public concern about exposure to the potential of contamination, whereas none was found at Love Canal. In this study, concern about environmental contamination and exposure was examined in relation to both perceived and actual proximity to a toxic waste disposal site (TWDS). It was hypothesized that perceived residential proximity would better predict concern levels that would actual residential distance. The data were abstracted from a New York State, excluding New York City, survey using all respondents (N = 317) from one county known to have a large number of TWDSs. Using linear regression, the variance explained in concern scores was 22 times higher with perceived distance than for actual distance. Perceived residential distance was a significant predictor of concern scores, while actual distance was not. However, perceived distance explained less than 5% of the variance in concern scores. PMID:3196077

  6. Actual and 'optimum' flight speeds: field data reassessed

    PubMed

    Pennycuick

    1997-01-01

    Previously published field observations of the air speeds of 36 species of birds, all observed by the same method (ornithodolite), were compared with estimates of the corresponding minimum power speeds, calculated with a default body drag coefficient of 0.1. This value, which was derived from recent wind tunnel studies, represents a downward revision from default values previously used and leads, in turn, to an upward revision of estimated minimum power speeds. The mean observed air speeds are now distributed around the minimum power speed, rather than in between the speeds for minimum power and maximum range, as they were before. Although the field data do not represent migration, examination of the marginal effects of small changes of speed, on power and lift:drag ratio, indicates that flying at the maximum range speed on migration may not represent an 'optimal' or even a practical strategy and that cruising speeds may be limited by the muscle power available or by aerobic capacity. Caution in constructing 'optimisation' theories is indicated.

  7. Characterization of personal RF electromagnetic field exposure and actual absorption for the general public.

    PubMed

    Joseph, W; Vermeeren, G; Verloock, L; Heredia, Mauricio Masache; Martens, Luc

    2008-09-01

    In this paper, personal electromagnetic field exposure of the general public due to 12 different radiofrequency sources is characterized. Twenty-eight different realistic exposure scenarios based upon time, environment, activity, and location have been defined and a relevant number of measurements were performed with a personal exposure meter. Indoor exposure in office environments can be higher than outdoor exposure: 95th percentiles of field values due to WiFi ranged from 0.36 to 0.58 V m(-1), and for DECT values of 0.33 V m(-1) were measured. The downlink signals of GSM and DCS caused the highest outdoor exposures up to 0.52 V m(-1). The highest total field exposure occurred for mobile scenarios (inside a train or bus) from uplink signals of GSM and DCS (e.g., mobile phones) due to changing environmental conditions, handovers, and higher required transmitted signals from mobile phones due to penetration through windows while moving. A method to relate the exposure to the actual whole-body absorption in the human body is proposed. An application is shown where the actual absorption in a human body model due to a GSM downlink signal is determined. Fiftieth, 95th, and 99 th percentiles of the whole-body specific absorption rate (SAR) due to this GSM signal of 0.58 microW kg(-1), 2.08 microW kg(-1), and 5.01 microW kg(-1) are obtained for a 95th percentile of 0.26 V m(-1). A practical usable function is proposed for the relation between the whole-body SAR and the electric fields. The methodology of this paper enables epidemiological studies to make an analysis in combination with both electric field and actual whole-body SAR values and to compare exposure with basic restrictions. PMID:18695413

  8. Intended release and actual retention of alfalfa leafcutting bees (Hymenoptera: Megachilidae) for pollination in commercial alfalfa seed fields.

    PubMed

    Pitts-Singer, Theresa L

    2013-04-01

    Low, medium, and high stocking densities (15,000; 30,000; and 45,000-50,000 bees per acre, respectively) of Megachile rotundata (F.) (Hymenoptera: Megachilidae), the alfalfa leafcutting bee, were released over 4 yr in three research plots of Utah alfalfa, Medicago sativa L. (Fabaceae), planted at seed-production rates. A low percentage of bees (46-79% of released) survived the incubation and field-emergence processes; of those bees, the number of females that established at the nesting sites was 25-100%. Of the three field sites, one site consistently retained more females and produced more completed nests than the other sites, all of which usually had poor female establishment and progeny production. In addition, floral resources were depleted over time, but many flowers remained unvisited over the season. Nest production decreased over time, as numbers of flowers and female bees declined. Significant positive relationships were found between the intended stocking densities and 1) the number of females that actually survived incubation and field emergence and 2) the number of females that established nests. The number of females that established nests was positively affected by the number of females that survived to emerge in the field. The percentage of females that established was not significantly affected by the intended number of released bees, countering a prediction that the release of fewer bees would allow more females to establish nests and achieve high reproductive success. For growers, it may be more frugal to use modest numbers of M. rotundata for pollination, because many of the bees at medium and high stocking densities do not nest in grower-provided bee boards.

  9. Intended release and actual retention of alfalfa leafcutting bees (Hymenoptera: Megachilidae) for pollination in commercial alfalfa seed fields.

    PubMed

    Pitts-Singer, Theresa L

    2013-04-01

    Low, medium, and high stocking densities (15,000; 30,000; and 45,000-50,000 bees per acre, respectively) of Megachile rotundata (F.) (Hymenoptera: Megachilidae), the alfalfa leafcutting bee, were released over 4 yr in three research plots of Utah alfalfa, Medicago sativa L. (Fabaceae), planted at seed-production rates. A low percentage of bees (46-79% of released) survived the incubation and field-emergence processes; of those bees, the number of females that established at the nesting sites was 25-100%. Of the three field sites, one site consistently retained more females and produced more completed nests than the other sites, all of which usually had poor female establishment and progeny production. In addition, floral resources were depleted over time, but many flowers remained unvisited over the season. Nest production decreased over time, as numbers of flowers and female bees declined. Significant positive relationships were found between the intended stocking densities and 1) the number of females that actually survived incubation and field emergence and 2) the number of females that established nests. The number of females that established nests was positively affected by the number of females that survived to emerge in the field. The percentage of females that established was not significantly affected by the intended number of released bees, countering a prediction that the release of fewer bees would allow more females to establish nests and achieve high reproductive success. For growers, it may be more frugal to use modest numbers of M. rotundata for pollination, because many of the bees at medium and high stocking densities do not nest in grower-provided bee boards. PMID:23786042

  10. Comprehensive Evaluation of Attitude and Orbit Estimation Using Actual Earth Magnetic Field Data

    NASA Technical Reports Server (NTRS)

    Deutschmann, Julie K.; Bar-Itzhack, Itzhack Y.

    2000-01-01

    A single, augmented Extended Kalman Filter (EKF), which simultaneously and autonomously estimates spacecraft attitude and orbit has been developed and successfully tested with real magnetometer and gyro data only. Because the earth magnetic field is a function of time and position, and because time is known quite precisely, the differences between the computed and measured magnetic field components, as measured by the magnetometers throughout the entire spacecraft orbit, are a function of both orbit and attitude errors. Thus, conceivably these differences could be used to estimate both orbit and attitude; an observability study validated this assumption. The results of testing the EKF with actual magnetometer and gyro data, from four satellites supported by the NASA Goddard Space Flight Center (GSFC) Guidance, Navigation, and Control Center, are presented and evaluated. They confirm the assumption that a single EKF can estimate both attitude and orbit when using gyros and magnetometers only.

  11. Strontium and Actinides Removal from Savannah River Site Actual Waste Samples by Freshly Precipitated Manganese Oxide

    SciTech Connect

    Barnes, M.J.

    2003-10-30

    The authors investigated the performance of freshly precipitated manganese oxide and monosodium titanate (MST) for the removal of strontium (Sr) and actinides from actual high-level waste. Manganese oxide precipitation occurs upon addition of a reductant such as formate (HCO2-) or peroxide (H2O2) to a waste solution containing permanganate (MnO4-). Tests described in this document address the capability of manganese oxide treatment to remove Rs, Pu, and Np from actual high-level waste containing elevated concentrations of Pu. Additionally, tests investigate MST (using two unique batches) performance with the same waste for direct comparison to the manganese oxide performance.

  12. Comparison of Statistically Modeled Contaminated Soil Volume Estimates and Actual Excavation Volumes at the Maywood FUSRAP Site - 13555

    SciTech Connect

    Moore, James; Hays, David; Quinn, John; Johnson, Robert; Durham, Lisa

    2013-07-01

    As part of the ongoing remediation process at the Maywood Formerly Utilized Sites Remedial Action Program (FUSRAP) properties, Argonne National Laboratory (Argonne) assisted the U.S. Army Corps of Engineers (USACE) New York District by providing contaminated soil volume estimates for the main site area, much of which is fully or partially remediated. As part of the volume estimation process, an initial conceptual site model (ICSM) was prepared for the entire site that captured existing information (with the exception of soil sampling results) pertinent to the possible location of surface and subsurface contamination above cleanup requirements. This ICSM was based on historical anecdotal information, aerial photographs, and the logs from several hundred soil cores that identified the depth of fill material and the depth to bedrock under the site. Specialized geostatistical software developed by Argonne was used to update the ICSM with historical sampling results and down-hole gamma survey information for hundreds of soil core locations. The updating process yielded both a best guess estimate of contamination volumes and a conservative upper bound on the volume estimate that reflected the estimate's uncertainty. Comparison of model results to actual removed soil volumes was conducted on a parcel-by-parcel basis. Where sampling data density was adequate, the actual volume matched the model's average or best guess results. Where contamination was un-characterized and unknown to the model, the actual volume exceeded the model's conservative estimate. Factors affecting volume estimation were identified to assist in planning further excavations. (authors)

  13. SITE EVALUATION OF FIELD PORTABLE PENTACHLOROPHENOL IMMUNOASSAYS

    EPA Science Inventory

    Four pentachlorophenol (PCP) enzyme immunoassays for environmental analysis have been evaluated through the U.S. EPA Superfund Innovative Technology Evaluation (SITE) program. Three assays were formatted for on-site field use and one assay could be used in a field laboratory sett...

  14. CANTON CAFO FIELD SITE STUDY - SITE CHARACTERIZATION AND CONTAMINANT IMPACTS

    EPA Science Inventory

    This presentation of CAFO research concerning the Canton CAFO field site study, including its characterization and contaminant impacts, was given at a NRMRL program review discussion of the CAFO Research Program.

  15. STEAM REFORMING TECHNOLOGY DEMONSTRATION FOR THE DESTRUCTION OF ORGANICS ON ACTUAL DOE SAVANNAH RIVER SITE TANK 48H WASTE 9138

    SciTech Connect

    Burket, P

    2009-02-24

    This paper describes the design of the Bench-scale Steam Reformer (BSR); a processing unit for demonstrating steam reforming technology on actual radioactive waste [1]. It describes the operating conditions of the unit used for processing a sample of Savannah River Site (SRS) Tank 48H waste. Finally, it compares the results from processing the actual waste in the BSR to processing simulant waste in the BSR to processing simulant waste in a large pilot scale unit, the Fluidized Bed Steam Reformer (FBSR), operated at Hazen Research Inc. in Golden, CO. The purpose of this work was to prove that the actual waste reacted in the same manner as the simulant waste in order to validate the work performed in the pilot scale unit which could only use simulant waste.

  16. Evaluation of TENORMs field measurement with actual activity concentration in contaminated soil matrices.

    PubMed

    Saint-Fort, Roger; Alboiu, Mirtyll; Hettiaratchi, Patrick

    2007-09-01

    The occurrence of technologically enhanced naturally occurring radioactive materials (TENORMs) concentrated through anthropogenic processes in contaminated soils at oil and gas facilities represent one of the most challenging issues facing the Canadian and US oil and gas industry today. Natural occurring radioactivity materials (NORMs) field survey techniques are widely used as a rapid and cost-effective method for ascertaining NORMs risks associated with contaminated soils and waste matrices as well other components comprising the environment. Because of potentially significant liability issues with Norms if not properly managed, the development of quantitative relationships between TENORMs field measurement techniques and laboratory analysis present a practical approach in facilitating the interim safe decision process since laboratory results can take days. The primary objective of this study was to evaluate the relationships between direct measurements of field radioactivity and various laboratory batch techniques using data collection technologies for NORM and actual laboratory radioactivity concentrations. The significance of selected soil characteristics that may improve or confound these relationships in the formulation of empirical models was also achieved as an objective. The soil samples used in this study were collected from 4 different locations in western Canada and represented a wide range in terms of their selected chemical and physical properties. Multiple regression analyses for both field and batch data showed a high level of correlation between radionuclides Ra-226 and Ra-228 as a function of data collection technologies and relevant soil parameters. All R2 values for the empirical models were greater than 0.80 and significant at P<0.05. The creation of these empirical models could be valuable in improving predictability of radium contamination in soils and therefore, reduce analytical costs as well as environmental liabilities.

  17. Cadmium and zinc interactions and their transfer in soil-crop system under actual field conditions.

    PubMed

    Nan, Zhongren; Li, Jijun; Zhang, Jianming; Cheng, Guodong

    2002-02-21

    The transfer of Cd and Zn from calcareous soils nearby a non-ferrous mining and smelting bases to the spring wheat (Triticum aestivum L.) and corn (Zea mays L.) tissues and the interactions between the two metals concerned were investigated under actual field conditions. Samples of soils and entire crops were randomly collected during harvest time in 1998 in the Baiyin region. The soil metal contents showed that the furrows had been polluted (mean values: 3.16 mg kg(-1) for Cd; 146.78 mg kg(-1) for Zn) and the significant spatial variation of the soil contamination existed here (ranges, Cd: 0.14-19.3 mg kg(-1); Zn: 43.5-565.0 mg kg(-1)). The translocation ratios of the two metals from soil to crop parts in the region studied were relatively lower and the order of the element transfer in different plant tissues was root > stem > grain. The transfer ratio of element Cd was lower than that of element Zn. Cd and Zn uptake by the crop structures could be best described by four models (P < 0.01): linear; exponential; quadratic; and cubic. Apart from a linear relationship between the element Cd in the corn grains and soils, models were generally non-lincar. An analysis of Cd-Zn interaction mechanism led to the conclusion that the effects of the two metals were synergistic to each other under field conditions, in which increasing Cd and Zn contents in soils could increase the accumulations of Zn or Cd in the two crops.

  18. "Actually, I Wanted to Learn": Study-Related Knowledge Exchange on Social Networking Sites

    ERIC Educational Resources Information Center

    Wodzicki, Katrin; Schwammlein, Eva; Moskaliuk, Johannes

    2012-01-01

    Social media open up multiple options to add a new dimension to learning and knowledge processes. Particularly, social networking sites allow students to connect formal and informal learning settings. Students can find like-minded people and organize informal knowledge exchange for educational purposes. However, little is known about in which way…

  19. Transport code for radiocolloid migration: with an assessment of an actual low-level waste site

    SciTech Connect

    Travis, B.J.; Nuttall, H.E.

    1984-12-31

    Recently, there is increased concern that radiocolloids may act as a rapid transport mechanism for the release of radionuclides from high-level waste repositories. The role of colloids is, however, controversial because the necessary data and assessment methodology have been limited. Evidence is accumulating to indicate that colloids are an important consideration in the geological disposal of nuclear waste. To quantitatively assess the role of colloids, the TRACR3D transport code has been enhanced by the addition of the population balance equations. This new version of the code can simulate the migration of colloids through combinations of porous/fractured, unsaturated, geologic media. The code was tested against the experimental laboratory column data of Avogadro et al. in order to compare the code results to both experimental data and an analytical solution. Next, a low-level radioactive waste site was investigated to explore whether colloid migration could account for the unusually rapid and long transport of plutonium and americium observed at a low-level waste site. Both plutonium and americium migrated 30 meters through unsaturated volcanic tuff. The nature and modeling of radiocolloids are discussed along with site simulation results from the TRACR3D code. 20 references.

  20. Site recycling: From Brownfield to football field

    SciTech Connect

    Lee, C.; Haas, W.L.

    1995-07-01

    The Carolina Panther`s new home, Carolinas Stadium, will be impressive. It will include a 75,000-seat stadium, about 2,000 parking spaces, and a practice facility equipped with three full-sized football fields, all located on 30 acres bordering the central business district of Charlotte, NC. Fans of the NFL expansion team may never know that, until recently, 13 of those 30 acres were a former state Superfund site contaminated by a commercial scrapyard that had operated from the early 1930s to 1983. The salvage of nonferrous metals from lead-acid batteries, copper from transformers and other electrical equipment, and ferrous metal scrap from junk automobiles at the Smith Metal and Iron (SMI) site had left a complex contamination legacy. The soil contained lead, polychlorinated biphenyls (PCBs), lesser amounts of semivolatiles (polyaromatic hydrocarbons, or PAHs), and volatile organic compounds and petroleum hydrocarbons. The site had remained dormant, like many former industrial sites that have come be called {open_quotes}brownfields,{close_quotes} for nearly a decade when in 1993, Charlotte was selected as the future home of the Carolina Panthers, a National Football League expansion team. The city was able to attract the team in part by offering to redevelop the site, a prime location adjacent to the downtown area. An eight-month-long site remediation effort by HDR Engineering Inc. was completed March 31, on schedule for a June 1996 unveiling of the team`s new facility.

  1. Assessment of actual transpiration rate in olive tree field combining sap-flow, leaf area index and scintillometer measurements

    NASA Astrophysics Data System (ADS)

    Agnese, C.; Cammalleri, C.; Ciraolo, G.; Minacapilli, M.; Provenzano, G.; Rallo, G.; de Bruin, H. A. R.

    2009-09-01

    Models to estimate the actual evapotranspiration (ET) in sparse vegetation area can be fundamental for agricultural water managements, especially when water availability is a limiting factor. Models validation must be carried out by considering in situ measurements referred to the field scale, which is the relevant scale of the modelled variables. Moreover, a particular relevance assumes to consider separately the components of plant transpiration (T) and soil evaporation (E), because only the first is actually related to the crop stress conditions. Objective of the paper was to assess a procedure aimed to estimate olive trees actual transpiration by combining sap flow measurements with the scintillometer technique at field scale. The study area, located in Western Sicily (Italy), is mainly cultivated with olive crop and is characterized by typical Mediterranean semi-arid climate. Measurements of sap flow and crop actual evapotranspiration rate were carried out during 2008 irrigation season. Crop transpiration fluxes, measured on some plants by means of sap flow sensors, were upscaled considering the leaf area index (LAI). The comparison between evapotranspiration values, derived by displaced-beam small-aperture scintillometer (DBSAS-SLS20, Scintec AG), with the transpiration fluxes obtained by the sap flow sensors, also allowed to evaluate the contribute of soil evaporation in an area characterized by low vegetation coverage.

  2. Low persistence of a monocarpic invasive plant in historical sites biases our perception of its actual distribution

    PubMed Central

    Pergl, Jan; Pyšek, Petr; Perglová, Irena; Jarošík, Vojtěch; Procheş, Şerban

    2012-01-01

    Aim As accurate and up-to-date distribution data for plant species are rarely available, cumulative records over long periods of time are frequently used for mapping distributions, without taking into account that species do not persist in their historical localities forever. However, persistence is highly relevant in changing modern landscapes, especially for invasive species that dynamically spread in unstable human-made habitats. We studied how an invasive species, Heracleum mantegazzianum, persists at sites once colonized and how its ability to persist affects its distribution. Location The Czech Republic. Methods We visited 521 localities of H. mantegazzianum occurrence reported in the literature and herbaria to determine whether the species still occurs at these sites. By using G-tests and classification trees, we explored the roles of various factors affecting its persistence at a site. Results Of the total number of 521 historical sites at which the species has occurred since the end of the 19th century, it persists at only 124 (23.8%). The persistence rate differs with respect to habitat type and is highest in meadows and forest margins. Analysis using classification trees indicated that the factors that best explain persistence are: type of habitat (with meadow and forest margins over-represented); urbanity (with a higher persistence outside urban areas); proximity to the place of the species’ introduction into the country; metapopulation connectivity; and distance to the nearest neighbouring population. Main conclusions The use of cumulative historical records as a measure of species distribution, which is common in invasion literature, can seriously overestimate the actual distribution of alien plant species with low persistence. In the case of alien species such as H. mantegazzanium, which is non-clonal and reproduces only by seed, estimates of distribution and spread based on historical data are informative about potentially suitable habitat but may

  3. Involved field radiation for Hodgkin's lymphoma: The actual dose to breasts in close proximity

    SciTech Connect

    Dabaja, Bouthaina; Wang Zhonglo; Stovall, Marilyn; Baker, Jamie S.; Smith, Susan A.; Khan, Meena; Ballas, Leslie; Salehpour, Mohammad R.

    2012-01-01

    To decrease the risk of late toxicities in Hodgkin's lymphoma (HL) patients treated with radiation therapy (RT) (HL), involved field radiation therapy (IFRT) has largely replaced the extended fields. To determine the out-of-field dose delivered from a typical IFRT to surrounding critical structures, we measured the dose at various points in an anthropomorphic phantom. The phantom is divided into 1-inch-thick slices with the ability to insert TLDs at 3-cm intervals grid spacing. Two treatment fields were designed, and a total of 45 TLDs were placed (equally spaced) at the margin of the each of the 2 radiation fields. After performing a computed tomography simulation, 2 treatment plans targeting the mediastinum, a typical treatment field in patients with early stage HL, were generated. A total dose of 3060 cGy was delivered to the gross tumor volume for each field consecutively. The highest measured dose detected at 1 cm from the field edge in the planning target volume was 496 cGy, equivalent to 16% of the isocentric dose. The dose dropped significantly with increasing distance from the field edge. It ranged from 1.1-3.9% of the isocentric dose at a distance of 3.2-4 cm to <1.6% at a distance of >6 cm. Although the computer treatment planning system (CTPS) frequently underestimated the dose delivered, the difference in dose between measured and generated by CTPS was <2.5% in 90 positions measured. The collateral dose of radiation to breasts from IFRT is minimal. The out-of-field dose, although mildly underestimated by CTPS, becomes insignificant at >3 cm from the field edge of the radiation field.

  4. Field site selection: getting it right first time around

    PubMed Central

    Malcolm, Colin A; El Sayed, Badria; Babiker, Ahmed; Girod, Romain; Fontenille, Didier; Knols, Bart GJ; Nugud, Abdel Hameed; Benedict, Mark Q

    2009-01-01

    The selection of suitable field sites for integrated control of Anopheles mosquitoes using the sterile insect technique (SIT) requires consideration of the full gamut of factors facing most proposed control strategies, but four criteria identify an ideal site: 1) a single malaria vector, 2) an unstructured, relatively low density target population, 3) isolation of the target population and 4) actual or potential malaria incidence. Such a site can exist in a diverse range of situations or can be created. Two contrasting SIT field sites are examined here: the desert-flanked Dongola Reach of the Nile River in Northern State, Sudan, where malaria is endemic, and the island of La Reunion, where autochthonous malaria is rare but risk is persistent. The single malaria-transmitting vector at both sites is Anopheles arabiensis. In Sudan, the target area is a narrow 500 km corridor stretching from the rocky terrain at the Fourth Cataract - just above the new Merowe Dam, to the northernmost edge of the species range, close to Egypt. Vector distribution and temporal changes in density depend on the Nile level, ambient temperature and human activities. On La Reunion, the An. arabiensis population is coastal, limited and divided into three areas by altitude and exposure to the trade winds on the east coast. Mosquito vectors for other diseases are an issue at both sites, but of primary importance on La Reunion due to the recent chikungunya epidemic. The similarities and differences between these two sites in terms of suitability are discussed in the context of area-wide integrated vector management incorporating the SIT. PMID:19917079

  5. Field site selection: getting it right first time around.

    PubMed

    Malcolm, Colin A; El Sayed, Badria; Babiker, Ahmed; Girod, Romain; Fontenille, Didier; Knols, Bart G J; Nugud, Abdel Hameed; Benedict, Mark Q

    2009-01-01

    The selection of suitable field sites for integrated control of Anopheles mosquitoes using the sterile insect technique (SIT) requires consideration of the full gamut of factors facing most proposed control strategies, but four criteria identify an ideal site: 1) a single malaria vector, 2) an unstructured, relatively low density target population, 3) isolation of the target population and 4) actual or potential malaria incidence. Such a site can exist in a diverse range of situations or can be created. Two contrasting SIT field sites are examined here: the desert-flanked Dongola Reach of the Nile River in Northern State, Sudan, where malaria is endemic, and the island of La Reunion, where autochthonous malaria is rare but risk is persistent. The single malaria-transmitting vector at both sites is Anopheles arabiensis. In Sudan, the target area is a narrow 500 km corridor stretching from the rocky terrain at the Fourth Cataract--just above the new Merowe Dam, to the northernmost edge of the species range, close to Egypt. Vector distribution and temporal changes in density depend on the Nile level, ambient temperature and human activities. On La Reunion, the An. arabiensis population is coastal, limited and divided into three areas by altitude and exposure to the trade winds on the east coast. Mosquito vectors for other diseases are an issue at both sites, but of primary importance on La Reunion due to the recent chikungunya epidemic. The similarities and differences between these two sites in terms of suitability are discussed in the context of area-wide integrated vector management incorporating the SIT. PMID:19917079

  6. Making the Difference for Teachers: The Field Experience in Actual Practice.

    ERIC Educational Resources Information Center

    Slick, Gloria Appelt, Ed.

    This is the third in a series of four books presenting a variety of field experience program models and philosophies that drive the programs provided to preservice teachers during their undergraduate teacher preparation. This publication explores the internal workings of the relationships and events that have an impact on all the persons involved…

  7. Need for more TB vaccine field sites.

    PubMed

    McShane, Helen

    2009-06-01

    Efforts to control the tuberculosis (TB) epidemic have been challenged by both the geographical overlap with the HIV pandemic, and the emergence of multi - and extensively - drug-resistant strains of Mycobacterium tuberculosis. There is, therefore, an urgent global need for an improved vaccine. However, the development of an improved vaccine is scientifically and logistically challenging. Immunological correlates or biomarkers of protection are not known and there is no perfect preclinical animal model with which to predict success in humans. Indeed, vaccine development in general is time-consuming and costly. One of the many road-blocks to the development of new TB vaccines is the availability of field sites that are suitable for large scale Phase IIb/III efficacy testing. Because disease incidence is low, even though prevalence is high, Phase IIb efficacy trials involve several thousand subjects, and require lengthy follow-up. Phase III licensure trials will need to be even larger, and are likely to require the involvement of multiple field sites. There is currently inadequate capacity within high-burden TB countries to conduct these essential trials. We need to invest now to expand current capacity if we are to reduce the time taken to develop new vaccines. PMID:19634709

  8. Numerical reconstruction of part of an actual blast-wave flow field to agree with available experimental data

    NASA Astrophysics Data System (ADS)

    Lau, S. C. M.; Gottlieb, J. J.

    1983-11-01

    A method of solution is presented and validated for the numerical reconstruction of a certain part of an actual blast-wave flow field of interest for planar, cylindrical and spherical explosions, away from the explosion source where the blast-wave has become sufficiently weak that real-gas effects are unimportant. This method involves, essentially, a trial-and-error process of constructing the best possible path of a fluid particle or equivalent piston at the upstream side of the flow field of interest such that the resulting flow field constructed numerically in front of the equivalent moving piston agrees as well as possible with all available although limited experimental data. The relatively new random-choice method was suitably modified to easily handle the numerical computations of the nonstationary flow in front of the moving piston. Finally, the present method is used to reconstruct the flow field for past TNT and ANFO explosions, for which the blast-wave amplitudes are less than about 1 MPa. These results are presented in convenient graphical and tabular form, scaled for the case of a 1-kg TNT surface explosion or its equivalent in a standard atmosphere, so that they can be utilized readily for different sized explosions at the same or other atmospheric conditions.

  9. BIOREMEDIATION FIELD INITIATIVE SITE PROFILE: ESCAMBIA WOOD PRESERVING SITE - BROOKHAVEN

    EPA Science Inventory

    The Escambia Wood Preserving Site—Brookhaven in Brookhaven, Mississippi, is a former wood preserving facility that used pentachlo- rophenol (PCP) and creosote to treat wooden poles. The site contains two pressure treatment cylinders, a wastewater treatment system, five bulk pr...

  10. Testing an Energy Balance Model for Estimating Actual Evapotranspiration Using Remotely Sensed Data. [Hannover, West Germany barley and wheat fields

    NASA Technical Reports Server (NTRS)

    Gurney, R. J.; Camillo, P. J.

    1985-01-01

    An energy-balance model is used to estimate daily evapotranspiration for 3 days for a barley field and a wheat field near Hannover, Federal Republic of Germany. The model was calibrated using once-daily estimates of surface temperatures, which may be remotely sensed. The evaporation estimates were within the 95% error bounds of independent eddy correlation estimates for the daytime periods for all three days for both sites, but the energy-balance estimates are generally higher; it is unclear which estimate is biassed. Soil moisture in the top 2 cm of soil, which may be remotely sensed, may be used to improve these evaporation estimates under partial ground cover. Sensitivity studies indicate the amount of ground data required is not excessive.

  11. Straight ladder inclined angle in a field environment: the relationship among actual angle, method of set-up and knowledge

    PubMed Central

    Chang, Wen-Ruey; Huang, Yueng-Hsiang; Chang, Chien-Chi; Brunette, Christopher; Fallentin, Nils

    2016-01-01

    Abstract Ladder inclined angle is a critical factor that could lead to a slip at the base of portable straight ladders, a major cause of falls from heights. Despite several methods established to help workers achieve the recommended 75.5° angle for ladder set-up, it remains unclear if these methods are used in practice. This study explored ladder set-up behaviours in a field environment. Professional installers of a company in the cable and other pay TV industry were observed for ladder set-up at their worksites. The results showed that the actual angles of 265 ladder set-ups by 67 participants averaged 67.3° with a standard deviation of 3.22°. Although all the participants had training on recommended ladder set-up methods, only 3 out of 67 participants applied these methods in their daily work and even they failed to achieve the desired 75.5° angle. Therefore, ladder set-up remains problematic in real-world situations. Practitioner Summary: Professional installers of a cable company were observed for portable straight ladder set-up at their worksites. The ladder inclined angle averaged 67.3° with a standard deviation of 3.22°, while the recommended angle is 75.5°. Only a few participants used the methods that they learned during training in their daily work. PMID:26672809

  12. Straight ladder inclined angle in a field environment: the relationship among actual angle, method of set-up and knowledge.

    PubMed

    Chang, Wen-Ruey; Huang, Yueng-Hsiang; Chang, Chien-Chi; Brunette, Christopher; Fallentin, Nils

    2016-08-01

    Ladder inclined angle is a critical factor that could lead to a slip at the base of portable straight ladders, a major cause of falls from heights. Despite several methods established to help workers achieve the recommended 75.5° angle for ladder set-up, it remains unclear if these methods are used in practice. This study explored ladder set-up behaviours in a field environment. Professional installers of a company in the cable and other pay TV industry were observed for ladder set-up at their worksites. The results showed that the actual angles of 265 ladder set-ups by 67 participants averaged 67.3° with a standard deviation of 3.22°. Although all the participants had training on recommended ladder set-up methods, only 3 out of 67 participants applied these methods in their daily work and even they failed to achieve the desired 75.5° angle. Therefore, ladder set-up remains problematic in real-world situations. Practitioner Summary: Professional installers of a cable company were observed for portable straight ladder set-up at their worksites. The ladder inclined angle averaged 67.3° with a standard deviation of 3.22°, while the recommended angle is 75.5°. Only a few participants used the methods that they learned during training in their daily work.

  13. A coupled remote sensing and simplified surface energy balance approach to estimate actual evapotranspiration from irrigated fields

    USGS Publications Warehouse

    Senay, G.B.; Budde, M.; Verdin, J.P.; Melesse, Assefa M.

    2007-01-01

    Accurate crop performance monitoring and production estimation are critical for timely assessment of the food balance of several countries in the world. Since 2001, the Famine Early Warning Systems Network (FEWS NET) has been monitoring crop performance and relative production using satellite-derived data and simulation models in Africa, Central America, and Afghanistan where ground-based monitoring is limited because of a scarcity of weather stations. The commonly used crop monitoring models are based on a crop water-balance algorithm with inputs from satellite-derived rainfall estimates. These models are useful to monitor rainfed agriculture, but they are ineffective for irrigated areas. This study focused on Afghanistan, where over 80 percent of agricultural production comes from irrigated lands. We developed and implemented a Simplified Surface Energy Balance (SSEB) model to monitor and assess the performance of irrigated agriculture in Afghanistan using a combination of 1-km thermal data and 250m Normalized Difference Vegetation Index (NDVI) data, both from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. We estimated seasonal actual evapotranspiration (ETa) over a period of six years (2000-2005) for two major irrigated river basins in Afghanistan, the Kabul and the Helmand, by analyzing up to 19 cloud-free thermal and NDVI images from each year. These seasonal ETa estimates were used as relative indicators of year-to-year production magnitude differences. The temporal water-use pattern of the two irrigated basins was indicative of the cropping patterns specific to each region. Our results were comparable to field reports and to estimates based on watershed-wide crop water-balance model results. For example, both methods found that the 2003 seasonal ETa was the highest of all six years. The method also captured water management scenarios where a unique year-to-year variability was identified in addition to water-use differences between

  14. A Coupled Remote Sensing and Simplified Surface Energy Balance Approach to Estimate Actual Evapotranspiration from Irrigated Fields

    PubMed Central

    Senay, Gabriel B.; Budde, Michael; Verdin, James P.; Melesse, Assefa M.

    2007-01-01

    Accurate crop performance monitoring and production estimation are critical for timely assessment of the food balance of several countries in the world. Since 2001, the Famine Early Warning Systems Network (FEWS NET) has been monitoring crop performance and relative production using satellite-derived data and simulation models in Africa, Central America, and Afghanistan where ground-based monitoring is limited because of a scarcity of weather stations. The commonly used crop monitoring models are based on a crop water-balance algorithm with inputs from satellite-derived rainfall estimates. These models are useful to monitor rainfed agriculture, but they are ineffective for irrigated areas. This study focused on Afghanistan, where over 80 percent of agricultural production comes from irrigated lands. We developed and implemented a Simplified Surface Energy Balance (SSEB) model to monitor and assess the performance of irrigated agriculture in Afghanistan using a combination of 1-km thermal data and 250-m Normalized Difference Vegetation Index (NDVI) data, both from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensor. We estimated seasonal actual evapotranspiration (ETa) over a period of six years (2000-2005) for two major irrigated river basins in Afghanistan, the Kabul and the Helmand, by analyzing up to 19 cloud-free thermal and NDVI images from each year. These seasonal ETa estimates were used as relative indicators of year-to-year production magnitude differences. The temporal water-use pattern of the two irrigated basins was indicative of the cropping patterns specific to each region. Our results were comparable to field reports and to estimates based on watershed-wide crop water-balance model results. For example, both methods found that the 2003 seasonal ETa was the highest of all six years. The method also captured water management scenarios where a unique year-to-year variability was identified in addition to water-use differences between

  15. On-site cell field test support program

    NASA Astrophysics Data System (ADS)

    Staniunas, J. W.; Merten, G. P.

    1982-09-01

    Utility sites for data monitoring were reviewed and selected. Each of these sites will be instrumented and its energy requirements monitored and analyzed for one year prior to the selection of 40 Kilowatt fuel cell field test sites. Analyses in support of the selection of sites for instrumentation shows that many building sectors offered considerable market potential. These sectors include nursing home, health club, restaurant, industrial, hotel/motel and apartment.

  16. Evaluation of a total dissolved solids model in comparison to actual field data measurements in the Cheyenne River, South Dakota, U.S.A.

    PubMed

    Berdanier, Bruce W; Ziadat, Anf H

    2006-06-01

    During the summers of 2002 and 2004, in-stream integrated flow and concentration measurements for the total dissolved solids in the Cheyenne River, South Dakota, USA was conducted in order to compare the obtained actual field measurements with the predictions values made by the Bureau of Reclamation in the Environmental Impact Statement. In comparison to the actual field measurements conducted in this study, The Bureau of Reclamation extension of a small database used in the analysis for the impact of operations at the Angostura Unit over the past 50 years and into the future to predict the annual total dissolved solid loadings doesn't represent the actual loading values and various conditions in the study area. Additional integrated flow and concentration sampling is required to characterize the impact of the current Angostura Dam operations and Angostura Irrigation District return flows on the Cheyenne River in different seasons of the year. PMID:16917716

  17. Global and site specific multimedia (field) studies

    SciTech Connect

    Cutshall, N.H.; Guerin, M.R.

    1987-01-01

    Experience with radioactive fallout, with organic contaminants and with heavy metals has amply demonstrated that cross-media transfers are common and that understanding the transport, cycling, and fate of these contaminants requires a multimedia approach. Nonetheless, pollutants with similar physical and chemical attributes may follow markedly different pathways. The frequency of exceptions to predictions based on simplistic models is also sufficient to show that direct investigation of environmental contamination is essential to confirm validity of models used for conceptualizing a problem or for control. Modeling based on multimedia premises and regulatory controls that encompass multimedia considerations are challenged by a dilemma, however. First, the development of multimedia models or regulatory frameworks represents simplification and generalization. This is true for several reasons: (1) inadequate understanding of physical and environmental factors which control specific cross-media transfer; (2) the absence of specific data on certain multimedia pollutant concentrations; (3) even the most powerful computers do not have sufficient speed and capacity to deal with the known complexities of natural systems. On the other hand, for contaminants such as mercury, it may be necessary to include great detail; the overall distribution in the environment may be less important than the rate of some minor process. With sufficient experience and good judgment of what can be ignored, the simplifications and generalizations can be made. For the present, and for the foreseeable future, however, they absolutely must be accompanied by thorough field validation and monitoring.

  18. A field guide for well site geologists: Cable tool drilling

    SciTech Connect

    Last, G.V.; Liikala, T.L.

    1987-12-01

    This field is intended for use by Pacific Northwest Laboratory well site geologists who are responsible for data collection during the drilling and construction of monitoring wells on the Hanford Site. This guide presents standardized methods for geologic sample collection and description, and well construction documentation. 5 refs., 5 figs., 2 tabs.

  19. Designing a Marketing Course with Field Site Visits

    ERIC Educational Resources Information Center

    Van Doren, Doris; Corrigan, Hope Bober

    2008-01-01

    A key goal of including field site visits in marketing courses is to give business students increased interaction with industry professionals and community leaders. Site visits give students a concrete idea of how different marketing disciplines work in the business world. Business students gain greater insight into a career in marketing from this…

  20. The School Site Planner. Land for Learning. Site Selection, Site Planning, Playgrounds, Recreation, and Athletic Fields.

    ERIC Educational Resources Information Center

    North Carolina State Dept. of Public Instruction, Raleigh. Div. of School Support.

    The selection and planning of sites for school facilities can be critical and difficult due to the varied and complex demands schools must satisfy. This publication addresses the many factors that need consideration during the process of site selection, planning, development, and use. The report examines not only the site selection and planning…

  1. Intensification of the aerobic bioremediation of an actual site soil historically contaminated by polychlorinated biphenyls (PCBs) through bioaugmentation with a non acclimated, complex source of microorganisms

    PubMed Central

    Di Toro, Sara; Zanaroli, Giulio; Fava, Fabio

    2006-01-01

    Background The biotreatability of actual-site polychlorinated biphenyl (PCB)-contaminated soils is often limited by their poor content of autochthonous pollutant-degrading microorganisms. In such cases, inoculation might be the solution for a successful bioremediation. Some pure and mixed cultures of characterized PCB degrading bacteria have been tested to this purpose. However, several failures have been recorded mostly due to the inability of inoculated microbes to compete with autochthonous microflora and to face the toxicity and the scarcity of nutrients occurring in the contaminated biotope. Complex microbial systems, such as compost or sludge, normally consisting of a large variety of robust microorganisms and essential nutrients, would have better chances to succeed in colonizing degraded contaminated soils. However, such sources of microorganisms have been poorly applied in soil bioremediation and in particular in the biotreatment of soil with PCBs. Thus, in this study the effects of Enzyveba, i.e. a consortium of non-adapted microorganisms developed from composted material, on the slurry- and solid-phase aerobic bioremediation of an actual-site, aged PCB-contaminated soil were studied. Results A slow and only partial biodegradation of low-chlorinated biphenyls, along with a moderate depletion of initial soil ecotoxicity, were observed in the not-inoculated reactors. Enzyveba significantly increased the availability and the persistence of aerobic PCB- and chlorobenzoic acid-degrading cultivable bacteria in the bioreactors, in particular during the earlier phase of treatment. It also markedly enhanced PCB-biodegradation rate and extent (from 50 to 100%) as well as the final soil detoxification, in particular under slurry-phase conditions. Taken together, data obtained suggest that Enzyveba enhanced the biotreatability of the selected soil by providing exogenous bacteria and fungi able to remove inhibitory or toxic intermediates of PCB biodegradation and

  2. Use of Field Research Sites to Teach Field Techniques in Graduate Level Soil Physics.

    ERIC Educational Resources Information Center

    Cassel, D. K.

    1986-01-01

    Describes how a field research site provides grauduate soil physics students with practical field-oriented experiences. Explains the structure of the course and the nature of the course's investigations. Assesses the advantages and obstacles associated with the field research technique. (ML)

  3. Multi-Sited Ethnography and the Field of Educational Research

    ERIC Educational Resources Information Center

    Pierides, Dean

    2010-01-01

    This paper responds to the challenge of how educational research might be practised in a contemporary world that is no longer necessarily organised by nearness and unity. Focusing on ethnography, it argues for what a multi-sited imaginary contributes to research in the field of education. By giving prominence to the notion of multi-sited…

  4. Evaluation of measurement reproducibility using the standard-sites data, 1994 Fernald field characterization demonstration project

    SciTech Connect

    Rautman, C.A.

    1996-02-01

    The US Department of Energy conducted the 1994 Fernald (Ohio) field characterization demonstration project to evaluate the performance of a group of both industry-standard and proposed alternative technologies in describing the nature and extent of uranium contamination in surficial soils. Detector stability and measurement reproducibility under actual operating conditions encountered in the field is critical to establishing the credibility of the proposed alternative characterization methods. Comparability of measured uranium activities to those reported by conventional, US Environmental Protection Agency (EPA)-certified laboratory methods is also required. The eleven (11) technologies demonstrated included (1) EPA-standard soil sampling and laboratory mass-spectroscopy analyses, and currently-accepted field-screening techniques using (2) sodium-iodide scintillometers, (3) FIDLER low-energy scintillometers, and (4) a field-portable x-ray fluorescence spectrometer. Proposed advanced characterization techniques included (5) alpha-track detectors, (6) a high-energy beta scintillometer, (7) electret ionization chambers, (8) and (9) a high-resolution gamma-ray spectrometer in two different configurations, (10) a field-adapted laser ablation-inductively coupled plasma-atomic emission spectroscopy (ICP-AES) technique, and (11) a long-range alpha detector. Measurement reproducibility and the accuracy of each method were tested by acquiring numerous replicate measurements of total uranium activity at each of two ``standard sites`` located within the main field demonstration area. Meteorological variables including temperature, relative humidity. and 24-hour rainfall quantities were also recorded in conjunction with the standard-sites measurements.

  5. Magnetic field survey at PG&E photovoltaic sites

    SciTech Connect

    Chang, G.J.; Jennings, C.

    1994-08-01

    Public awareness has aroused concerns over the possible effects of magnetic fields on human health. While research continues to determine if magnetic fields do, in fact, affect human health, concerned individuals are requesting data on magnetic field sources in their environments to base personal decisions about limiting their exposure to these sources. Timely acceptance and implementation of photovoltaics (PV), particularly for distributed applications such as PV rooftops, windows, and vehicles, may be hampered by the lack of PV magnetic field data. To address this situation, magnetic flux density was measured around equipment at two PVUSA (Photovoltaics for Utility Scale Applications) project sites in Kerman and Davis, California. This report documents the data and compares the PV magnetic fields with published data on more prevalent magnetic field sources. Although not comprehensive, electric and magnetic field (EMF) data taken at PVUSA indicate that 60-Hz magnetic fields (the EMF type of greatest public concern) are significantly less for PV arrays than for household applications. Therefore, given the present EMF research knowledge, PV array EMF may not merit considerable concern. The PV system components exhibiting significant AC magnetic fields are the transformers and power conditioning units (PCUs). However, the AC magnetic fields associated with these components are localized and are not detected at PV system perimeters. Concern about transformer and PCU EMF would apply to several generation and storage technologies.

  6. Large field excursions from a few site relaxion model

    NASA Astrophysics Data System (ADS)

    Fonseca, N.; de Lima, L.; Machado, C. S.; Matheus, R. D.

    2016-07-01

    Relaxion models are an interesting new avenue to explain the radiative stability of the Standard Model scalar sector. They require very large field excursions, which are difficult to generate in a consistent UV completion and to reconcile with the compact field space of the relaxion. We propose an N -site model which naturally generates the large decay constant needed to address these issues. Our model offers distinct advantages with respect to previous proposals: the construction involves non-Abelian fields, allowing for controlled high-energy behavior and more model building possibilities, both in particle physics and inflationary models, and also admits a continuum limit when the number of sites is large, which may be interpreted as a warped extra dimension.

  7. Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Sites, 1992

    SciTech Connect

    none,

    1993-12-14

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2,668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling environmental remediation, i.e., the U.S. DOE, the Nuclear Regulatory Commission (NRC), and the California State Department of Health Services (DHS) Radiologic Health Branch (RHB). For that reason, information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major area of interest is radiological, this report also includes a discussion of nonradiological monitoring at SSFL.

  8. Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Sites, 1993

    SciTech Connect

    None, None

    1994-10-21

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2,668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling environmental remediation, i.e., the U.S. DOE, the Nuclear Regulatory Commission (NRC), and the California State Department of Health Services (DHS) Radiologic Health Branch (RHB). For that reason, information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major area of interest is radiological, this report also includes a discussion of nonoradiological monitoring at SSFL.

  9. Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Site, 1991

    SciTech Connect

    none,

    1992-12-03

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2.668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling operations with nuclear fuel or nuclear reactors. i.e., the U.S. DOE and the California State Department of Health Services (DHS). Radiologic Health Branch (RHB). For that reason. information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major area of interest is radiological, this report also includes a discussion of nonradiological monitoring at SSFL.

  10. Controlling activation site density by low-energy far-field stimulation in cardiac tissue.

    PubMed

    Hörning, Marcel; Takagi, Seiji; Yoshikawa, Kenichi

    2012-06-01

    Tachycardia and fibrillation are potentially fatal arrhythmias associated with the formation of rotating spiral waves in the heart. Presently, the termination of these types of arrhythmia is achieved by use of antitachycardia pacing or cardioversion. However, these techniques have serious drawbacks, in that they either have limited application or produce undesirable side effects. Low-energy far-field stimulation has recently been proposed as a superior therapy. This proposed therapeutic method would exploit the phenomenon in which the application of low-energy far-field shocks induces a large number of activation sites ("virtual electrodes") in tissue. It has been found that the formation of such sites can lead to the termination of undesired states in the heart and the restoration of normal beating. In this study we investigate a particular aspect of this method. Here we seek to determine how the activation site density depends on the applied electric field through in vitro experiments carried out on neonatal rat cardiac tissue cultures. The results indicate that the activation site density increases exponentially as a function of the intracellular conductivity and the level of cell isotropy. Additionally, we report numerical results obtained from bidomain simulations of the Beeler-Reuter model that are quantitatively consistent with our experimental results. Also, we derive an intuitive analytical framework that describes the activation site density and provides useful information for determining the ratio of longitudinal to transverse conductivity in a cardiac tissue culture. The results obtained here should be useful in the development of an actual therapeutic method based on low-energy far-field pacing. In addition, they provide a deeper understanding of the intrinsic properties of cardiac cells.

  11. Controlling activation site density by low-energy far-field stimulation in cardiac tissue

    NASA Astrophysics Data System (ADS)

    Hörning, Marcel; Takagi, Seiji; Yoshikawa, Kenichi

    2012-06-01

    Tachycardia and fibrillation are potentially fatal arrhythmias associated with the formation of rotating spiral waves in the heart. Presently, the termination of these types of arrhythmia is achieved by use of antitachycardia pacing or cardioversion. However, these techniques have serious drawbacks, in that they either have limited application or produce undesirable side effects. Low-energy far-field stimulation has recently been proposed as a superior therapy. This proposed therapeutic method would exploit the phenomenon in which the application of low-energy far-field shocks induces a large number of activation sites (“virtual electrodes”) in tissue. It has been found that the formation of such sites can lead to the termination of undesired states in the heart and the restoration of normal beating. In this study we investigate a particular aspect of this method. Here we seek to determine how the activation site density depends on the applied electric field through in vitro experiments carried out on neonatal rat cardiac tissue cultures. The results indicate that the activation site density increases exponentially as a function of the intracellular conductivity and the level of cell isotropy. Additionally, we report numerical results obtained from bidomain simulations of the Beeler-Reuter model that are quantitatively consistent with our experimental results. Also, we derive an intuitive analytical framework that describes the activation site density and provides useful information for determining the ratio of longitudinal to transverse conductivity in a cardiac tissue culture. The results obtained here should be useful in the development of an actual therapeutic method based on low-energy far-field pacing. In addition, they provide a deeper understanding of the intrinsic properties of cardiac cells.

  12. Research at Hanford's 300 Area Integrated Field Challenge Site

    NASA Astrophysics Data System (ADS)

    Zachara, J.; Rockhold, M.; Fredrickson, J.; Vermeul, V.; Ward, A.; Liu, C.; McKinley, J.; Bjornstad, B.; Freshley, M.; Haggerty, R.; Kent, D.; Lichtner, P.; Rubin, Y.; Versteeg, R.; Zheng, C.

    2008-12-01

    The U.S. Department of Energy - Environmental Remediation Sciences Division is supporting an Integrated Field Challenge (IFC) Site at Hanford's 300 Area. This site, immediately adjacent to the Columbia R., is the location of a groundwater uranium plume that resulted from past discharges of liquid effluent to unlined disposal ponds and trenches. Plume concentrations have persisted above the drinking water standard in spite of the cessation of all liquid discharges more than 15 years ago and significant efforts to excavate and remove contaminated sediments. The persistence of the uranium plume is postulated to be a result of a complex interplay between hydrological, geochemical, and microbiological processes, and rate-limited mass transfer in the highly heterogeneous sediments. An IFC research site has been established in the area of one of the former disposal ponds to provide the infrastructure for developing improved understanding of the mechanisms responsible for the uranium plume persistence, with an ultimate goal of providing a robust, scientific basis for future remediation decisions. Thirty-five wells were installed at the site in FY08 for subsurface characterization and monitoring of field experiments. Detailed characterization studies have been performed or are currently underway using a variety of hydrological, geophysical, geochemical, and microbiological methods. In addition to field experiments, a series of column and bench-scale transport experiments are being performed to measure process interactions at smaller scales under well-controlled laboratory conditions, and to parameterize mechanistically-based model representations of these processes. This presentation gives an overview of guiding hypotheses for the 300 Area IFC Site, the well layout and instrumentation, initial characterization results, and ongoing or planned experiments and modeling activities.

  13. Actual Condition of Paddy Field Levee Maintenance by Various Farm Households including Large-scale Farming in the Developed Land Renting Area

    NASA Astrophysics Data System (ADS)

    Sakata, Yasuyo

    The survey of interview, resource acquisition, photographic operation, and questionnaire were carried out in the “n” Community in the “y” District in Hakusan City in Ishikawa Prefecture to investigate the actual condition of paddy field levee maintenance in the area where land-renting market was proceeding, large-scale farming was dominant, and the problems of geographically scattered farm-land existed. In the study zone, 1) an agricultural production legal person rent-cultivated some of the paddy fields and maintained the levees, 2) another agricultural production legal person rent-cultivated some of the soy bean fields for crop changeover and land owners maintained the levees. The results indicated that sufficient maintenance was executed on the levees of the paddy fields cultivated by the agricultural production legal person, the soy bean fields for crop changeover, and the paddy fields cultivated by the land owners. Each reason is considered to be the managerial strategy, the economic incentive, the mutual monitoring and cross-regulatory mechanism, etc.

  14. Rocketdyne Division annual site environmental report Santa Susana Field Laboratory and Desoto sites 1995

    SciTech Connect

    1996-07-30

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation (Rocketdyne). These are identified as the Santa Susana Field Laboratory (SSFL) and the DeSoto site. The sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The DeSoto site essentially comprises office space and light industry with no remaining radiological operations, and has little potential impact on the environment. The SSFL site, because of its large size (2,668 acres), warrants comprehensive monitoring to assure protection of the environment. SSFL consists of four administrative areas used for research, development, and test operations as well as a buffer zone. A portion of Area I and all of Area II are owned by the U.S. Government and assigned to the National Aeronautics and Space Administration (NASA). A portion of Area IV is under option for purchase by the Department of Energy (DOE).

  15. Rocketdyne division annual site environmental report, Santa Susana Field Laboratory and De Soto Sites, 1994

    SciTech Connect

    none,

    1995-09-30

    This annual report discusses environmental monitoring at two manufacturing and test operations sites operated in the Los Angeles area by the Rocketdyne Division of Rockwell International Corporation (Rocketdyne). These are identified as the Santa Susana Field Laboratory (SSFL) and the De Soto site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto site is essentially light industry with some laboratory-scale R&D and has little potential impact on the environment. The SSFL site, because of its large size (2.668 acres), warrants comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring of DOE-sponsored activities to the regulatory agencies. i.e., the U.S. DOE, the Nuclear Regulatory Commission (NRC), and the California State Department of Health Services (DHS) Radiologic Health Branch (RHB). For that reason, information concentrates on Area IV at SSFL. which is the only area where DOE activities have been performed. While the major focus of attention is radiological, this report also includes a discussion of nonradiological monitoring at SSFL.

  16. Site Characterization for a Deep Borehole Field Test

    NASA Astrophysics Data System (ADS)

    Kuhlman, K. L.; Hardin, E. L.; Freeze, G. A.; Sassani, D.; Brady, P. V.

    2015-12-01

    The US Department of Energy Office of Nuclear Energy is at the beginning of 5-year Deep Borehole Field Test (DBFT) to investigate the feasibility of constructing and characterizing two boreholes in crystalline basement rock to a depth of 5 km (16,400 ft). The concept of deep borehole disposal for radioactive waste has some advantages over mined repositories, including incremental construction and loading, the enhanced natural barriers provided by deep continental crystalline basement, and reduced site characterization. Site characterization efforts need to determine an eligible site that does not have the following disqualifying characteristics: greater than 2 km to crystalline basement, upward vertical fluid potential gradients, presence of economically exploitable natural resources, presence of high permeability connection to the shallow subsurface, and significant probability of future seismic or volcanic activity. Site characterization activities for the DBFT will include geomechanical (i.e., rock in situ stress state, and fluid pressure), geological (i.e., rock and fracture infill lithology), hydrological (i.e., quantity of fluid, fluid convection properties, and solute transport mechanisms), and geochemical (i.e., rock-water interaction and natural tracers) aspects. Both direct (i.e., sampling and in situ testing) and indirect (i.e., borehole geophysical) methods are planned for efficient and effective characterization of these site aspects and physical processes. Borehole-based characterization will be used to determine the variability of system state (i.e., stress, pressure, temperature, and chemistry) with depth, and interpretation of material and system parameters relevant to numerical site simulation. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the U.S. Department of Energy's National Nuclear Security Administration under contract DE

  17. Site Study Plan for Aesthetics, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-06-01

    The Aesthetic Site Study Plan describes a field program consisting of identification of the visually affected area; determination of scenic quality, visual sensitivity, and visual management classes of the site and vicinity; and analysis of the level of visual contrast that would be created by the project. Field ratings of scenic quality, visual sensitivity, and visual contrast will be supplemented by a public perception survey designed to incorporate the views of the public. This plan describes the need for the study, the study design, data management and use, schedule for proposed activities, and quality assurance program. This study will provide data needed to satisfy requirements contained in, or derived from, SRPO Requirement Document (SRP-RD). 35 refs., 6 figs., 2 tabs.

  18. AmeriFlux US-Br3 Brooks Field Site 11- Ames

    SciTech Connect

    Parkin, Tim; Prueger, John

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Br3 Brooks Field Site 11- Ames. Site Description - The Brooks Field Site 11 - Ames Site is one of three sites (Brooks Field Site 10 and Brooks Field Site 1011) located in a corn/soybean agricultural landscape of central Iowa. The farming systems, associated tillage, and nutrient management practices for soybean/corn production are typical of those throughout Upper Midwest Corn Belt. All three sites are members of the AmeriFlux network. Information for all three can be found in synchronous pages of this website.

  19. AmeriFlux US-Br1 Brooks Field Site 10- Ames

    SciTech Connect

    Parkin, Tim; Prueger, John

    2016-01-01

    This is the AmeriFlux version of the carbon flux data for the site US-Br1 Brooks Field Site 10- Ames. Site Description - The Brooks Field Site 10 - Ames Site is one of three sites (Brooks Field Site 11 and Brooks Field Site 1011) located in a corn/soybean agricultural landscape of central Iowa. The farming systems, associated tillage, and nutrient management practices for soybean/corn production are typical of those throughout Upper Midwest Corn Belt. All three sites are members of the AmeriFlux network. Information for all three can be found in synchronous pages of this website.

  20. Site Study Plan for Acoustics, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-06-01

    The Acoustics site study plan describes a field program which characterizes existing sound levels, determines the area's sound propagation characteristics, and monitors the project-related sound emissions. The plan describes for each study: the need for the study, study design, data management and use, schedule, and quality assurance requirements. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Requirements Document. 37 refs., 9 figs., 3 tabs.

  1. Discrimination of rapeseed and weeds under actual field conditions based on principal component analysis and artificial neural network by VIS/NIR spectroscopy

    NASA Astrophysics Data System (ADS)

    Huang, Min; Bao, Yidan; He, Yong

    2007-11-01

    The study documented successful discrimination between five weed species and rapeseed plants under actual field conditions using visible and near infrared (Vis/NIR) spectroscopy. A hybrid recognition model, BP artificial neural networks (BP-ANN) combined with principal component analysis (PCA), had been established for discrimination of weeds in rapeseed field. Spectra tests were performed on the rapeseed and five-weed species canopy of 180 samples in the field using a spectrophotometer (325-1075 nm). 6 optimal PCs were selected as the input of BP neural networks to build the prediction model. Rapeseed samples were marked as 1, while the five weed species marked as 2, 3, 4, 5, 6, which were used as output set of BP-ANN. 120 samples were randomly selected as the training set, and the remainder as prediction set. It showed excellent predictions with the correlation value of 0.9745, and the relative standard deviation (RSD) was under 5% thus 100% of prediction accuracy was achieved. The results are promising for further work in real-time identification of weed patches in rapeseed fields for precision weed management.

  2. Cyanobiont diversity within and among cycads of one field site.

    PubMed

    Zimmerman, W J; Rosen, B H

    1992-12-01

    Limited diversity was found among cyanobionts from a cultivated population of cycads at a field site in Florida. All isolates were classified as Nostoc but were different from the one Nostoc species found in the soil. These cyanobacteria were root endophytes of several plants of Zamia integrifolia and one of Dioon. The isolates were similar morphologically and in their reactions to four fluorescein isothiocyanate conjugated lectins. Electrophoretic protein profiles and zymograms distinguished one cyanobiont and the soil Nostoc. A tenacious Anabaena epiphyte was also discovered inhabiting the surfaces of root nodules.

  3. The Field Lysimeter Test Facility (FLTF) at the Hanford Site: Installation and initial tests

    SciTech Connect

    Gee, G.W.; Kirkham, R.R.; Downs, J.L.; Campbell, M.D.

    1989-02-01

    The objectives of this program are to test barrier design concepts and to demonstrate a barrier design that meets established performance criteria for use in isolating wastes disposed of near-surface at the Hanford Site. Specifically, the program is designed to assess how well the barriers perform in controlling biointrusion, water infiltration, and erosion, as well as evaluating interactions between environmental variables and design factors of the barriers. To assess barrier performance and design with respect to infiltration control, field lysimeters and small- and large-scale field plots are planned to test the performance of specific barrier designs under actual and modified (enhanced precipitation) climatic conditions. The Field Lysimeter Test Facility (FLTF) is located in the 600 Area of the Hanford Site just east of the 200 West Area and adjacent to the Hanford Meteorological Station. The FLTF data will be used to assess the effectiveness of selected protective barrier configurations in controlling water infiltration. The facility consists of 14 drainage lysimeters (2 m dia x 3 m deep) and four precision weighing lysimeters (1.5 m x 1.5 m x 1.7 m deep). The lysimeters are buried at grade and aligned in a parallel configuration, with nine lysimeters on each side of an underground instrument chamber. The lysimeters were filled with materials to simulate a multilayer protective barrier system. Data gathered from the FLTF will be used to compare key barrier components and to calibrate and test models for predicting long-term barrier performance.

  4. Electrostatic fields in the active sites of lysozymes.

    PubMed

    Sun, D P; Liao, D I; Remington, S J

    1989-07-01

    Considerable experimental evidence is in support of several aspects of the mechanism that has been proposed for the catalytic activity of lysozyme. However, the enzymatically catalyzed hydrolysis of polysaccharides proceeds over 5 orders of magnitude faster than that of model compounds that mimic the configuration of the substrate in the active site of the enzyme. Although several possible explanations for this rate enhancement have been discussed elsewhere, a definitive mechanism has not emerged. Here we report striking results obtained by classical electrodynamics, which suggest that bond breakage and the consequent separation of charge in lysozyme is promoted by a large electrostatic field across the active site cleft, produced in part by a very asymmetric distribution of charged residues on the enzyme surface. Lysozymes unrelated in amino acid sequence have similar distributions of charged residues and electric fields. The results reported here suggest that the electrostatic component of the rate enhancement is greater than 9 kcal.mol-1. Thus, electrostatic interactions may play a more important role in the enzymatic mechanism than has generally been appreciated.

  5. Site Guidelines for a Deep Borehole Field Test

    NASA Astrophysics Data System (ADS)

    Sassani, D.; Kuhlman, K. L.; Freeze, G. A.; MacKinnon, R. J.; Perry, F.

    2015-12-01

    The US DOE Office of Nuclear Energy Used Nuclear Fuel Disposition Campaign (UFDC) is initiating a Deep Borehole Field Test (DBFT), without use of any radioactive waste, to evaluate the geoscience of the approach and technical capabilities for implementation. DOE has identified Sandia National Laboratories (SNL) as the Technical Lead for the UFDC DBFT Project, with the role of supporting DOE in (i) developing the overall DBFT Project Plan, (ii) management and integration of all DBFT Project activities, and (iii) providing Project technical guidance to DOE, other DOE National Laboratories, and university partners. The DBFT includes drilling one Characterization Borehole (CB-8.5" diameter), followed by an optional Field Test Borehole (FTB), to a depth of about 5,000 m (16,400 feet) into crystalline basement rock in a geologically stable continental location. The DBFT CB will be drilled and completed to facilitate downhole scientific testing and analyses. If site conditions are found to be favorable, DOE may drill the larger-diameter (17") FTB to facilitate proof-of-concept of handling, emplacement, and retrieval activities using surrogate waste containers. Guidelines for favorable DBFT site geohydrochemical and geomechanical conditions will be discussed and status of the DBFT Project will be provided. Sandia National Laboratories is a multi-program laboratory managed and operated by Sandia Corporation, a wholly owned subsidiary of Lockheed Martin Corporation, for the United States Department of Energy's National Nuclear Security Administration under contract DE-AC04-94AL85000. SAND2015-6426A.

  6. IAEA workshop and field trial at the Oak Ridge K-25 Site

    SciTech Connect

    Hembree, D.M. Jr.; Ross, H.H.; Carter, J.A.

    1995-03-01

    In March 1994, members of the International Safeguards Department in the National Security Program Office (NSPO) hosted an environmental monitoring field trial workshop for International Atomic Energy Agency (IAEA) inspectors. The workshop was held at the Oak Ridge K-25 Site and its primary purpose was to train the inspectors in the techniques needed for effective environmental sample collection and handling. The workshop emphasized both sampling theory and practice. First, detailed techniques for swipe, vegetation, soil, biota, and water-associated sampling were covered in the classroom. Subsequently, the inspectors were divided into three groups for actual sample collection in and around the K-25 locale. The collected samples were processed by the Department of Energy (DOE) Network of Analytical Laboratories using established analytical techniques. This activity is part of the IAEA ``Programme 93+2 in. assessment of measures to enhance IAEA safeguards.

  7. Preliminary Study on the Radar Vegetation Index (RVI) Application to Actual Paddy Fields by ALOS/PALSAR Full-polarimetry SAR Data

    NASA Astrophysics Data System (ADS)

    Yamada, Y.

    2015-04-01

    Kim and van Zyl (2001) proposed a kind of radar vegetation index (RVI). RVI = 4*min(λ1, λ2, λ3) / (λ1 + λ2 + λ3) They modified the equation as follows. (2009) RVI = 8 * σ0hv / (σ0hh + σ0vv +σ0hv ) by L-band full-polarimetric SAR data. They applied it into rice crop and soybean. (Y.Kim, T.Jackson et al., 2012) They compared RVI for L-, C- and X-bands to crop growth data, LAI and NDVI. They found L-band RVI was well correlated with Vegetation Water Content, LAI and NDVI. But the field data were collected by the multifrequency polarimetric scatterometer. The platform height was 4.16 meters from the ground. The author tried to apply the method to actual paddy fields near Tsukuba science city in Japan using ALOS/PALSAR, full-polarimetry L-band SAR data. The staple crop in Eastern Asia is rice and paddy fields are dominant land use. A rice-planting machine comes into wide use in this areas. The young rice plants were bedded regularly ridged line in the paddy fields by the machine. The space between two ridges of rice plants is about 30 cm and the wave length of PALSAR sensor is about 23 cm. Hence the Bragg scattering will appear depending upon the direction of the ridges of paddy fields. Once the Bragg scattering occurs, the backscattering values from the pixels should be very high comparing the surrounding region. Therefore the radar vegetation index (RVI) would be saturated. The RVI did not follow the increasing of vegetation anymore. Japan has launched ALOS-2 satellite and it has PALSAR-2, L-band SAR. Therefore RVI application product by PALSAR-2 will be watched with deep interest.

  8. Site study plan for ecology, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary Draft

    SciTech Connect

    Not Available

    1987-06-01

    The Ecology Site Study Plan describes a field program consisting of studies which include surveys for endangered, threatened, and candidate species; vegetation characterization, including mapping and cover typing, plant succession, wetlands description, and preexisting stresses; and wildlife community characterization, including availability and quality of habitats and descriptions of mammal, bird, reptile, amphibian, and invertebrate populations. The plan for each study describes the need for the study, study design, data management and use, schedule and personnel requirements, and quality assurance. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Project Requirements Document (SRP-RD). 83 refs., 3 tabs.

  9. Estimation of Actual Crop ET of Paddy Using the Energy Balance Model SMARET and Validation with Field Water Balance Measurements and a Crop Growth Model (ORYZA)

    NASA Astrophysics Data System (ADS)

    Nallasamy, N. D.; Muraleedharan, B. V.; Kathirvel, K.; Narasimhan, B.

    2014-12-01

    Sustainable management of water resources requires reliable estimates of actual evapotranspiration (ET) at fine spatial and temporal resolution. This is significant in the case of rice based irrigation systems, one of the major consumers of surface water resources and where ET forms a major component of water consumption. However huge tradeoff in the spatial and temporal resolution of satellite images coupled with lack of adequate number of cloud free images within a growing season act as major constraints in deriving ET at fine spatial and temporal resolution using remote sensing based energy balance models. The scale at which ET is determined is decided by the spatial and temporal scale of Land Surface Temperature (LST) and Normalized Difference Vegetation Index (NDVI), which form inputs to energy balance models. In this context, the current study employed disaggregation algorithms (NL-DisTrad and DisNDVI) to generate time series of LST and NDVI images at fine resolution. The disaggregation algorithms aimed at generating LST and NDVI at finer scale by integrating temporal information from concurrent coarse resolution data and spatial information from a single fine resolution image. The temporal frequency of the disaggregated images is further improved by employing composite images of NDVI and LST in the spatio-temporal disaggregation method. The study further employed half-hourly incoming surface insolation and outgoing long wave radiation obtained from the Indian geostationary satellite (Kalpana-1) to convert the instantaneous ET into daily ET and subsequently to the seasonal ET, thereby improving the accuracy of ET estimates. The estimates of ET were validated with field based water balance measurements carried out in Gadana, a subbasin predominated by rice paddy fields, located in Tamil Nadu, India.

  10. Site Study Plan for soils, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-06-01

    The Soils Site Study Plan describes a field program consisting of a soil characterization survey, impact monitoring of soils, predisturbance soil salinity survey, and a reclamation suitability study. This information will be used to plan for soil stripping, stockpiling, and replacement; reclamation of soils; determining predisturbance chemical and physical characteristics of the soils; including salinity levels; and monitoring for changes in chemical and physical characteristics of the soil. The SSP describes for each study the need for the study, the study design, data management and use, schedule of proposed activities, and the quality assurance program. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Project Requirements Document. 75 refs., 10 figs., 5 tabs.

  11. Characterization of instrumented sites for Onsite Fuel-Cell Field-Test project. Volume 3. Topical report, 1983-1985

    SciTech Connect

    Racine, W.C.; Campillo, C.J.

    1986-11-01

    During the site-selection phase of the Onsite Fuel-Cell Field Test, nearly one hundred sites throughout the U.S. were each instrumented with a standard data-acquisition system (DAS) to collect hourly electrical and thermal data for one year. Seventy of those sites are included in the report. Each site's electrical and thermal systems were instrumented including ambient temperature, electrical demands, building gas usage, and other parameters necessary to calculate building thermal loads. Multifamily residential, commercial, and light industrial sites were instrumented. Approximately twenty market sectors were represented including restaurants, hospitals, hotels, apartments, health clubs, nursing homes, and food processing plants. The primary use of the data was to determine site compatibility for the installation of 40-kW fuel-cell power plants. However, the collected energy data and site-specific information summarized in this comprehensive report may also be useful for other applications such as market characterization and simulation of new or improved energy-utilization equipment in actual sites. This volume focuses on hotels, laundries, and restaurants.

  12. Technical procedures for implementation of aesthetics site studies, Deaf Smith County site, Texas: Environmental Field Program

    SciTech Connect

    Not Available

    1987-06-01

    This chapter introduces the purpose and scope of the visually affected areas determination, as well as definitions, interfaces, and concurrent data needs. This procedure provides a method for determining the extent of visibility of the project. This area is identified as the visually affected area, and becomes the area within which all visual analysis is conducted. The visually affected area analysis of the Deaf Smith County site will involve identifying and mapping the visibility of all major proposed project features. Baseline analysis will be conducted within the overall visually affected area; impact assessment will be conducted within the visually affected area of each major project feature. This procedure presents the guidelines for determining the visually affected area will be in computer data base construction; viewshed modeling, and site visit and verification of results. Computer data base construction will involve digitizing topographic and project facility data from available data source. The extent of the visible area from each major project feature will then be plotted. Finally, these computer-generated visibility plots will be verified in the field.

  13. Virtual and Actual: Relative Accuracy of On-Site and Web-based Instruments in Auditing the Environment for Physical Activity

    PubMed Central

    Ben-Joseph, Eran; Lee, Jae Seung; Cromley, Ellen K.; Laden, Francine; Troped, Philip J.

    2015-01-01

    Objectives To assess the relative accuracy and usefulness of web tools in evaluating and measuring street-scale built environment characteristics. Methods A well-known audit tool was used to evaluate 84 street segments at the urban edge of metropolitan Boston, Massachusetts, using on-site visits and three web-based tools. The assessments were compared to evaluate their relative accuracy and usefulness. Results Web-based audits, based-on Google Maps, Google Street View, and MS Visual Oblique, tend to strongly agree with on-site audits on land-use and transportation characteristics (e.g., types of buildings, commercial destinations, and streets). However, the two approaches to conducting audits (web versus on-site) tend to agree only weakly on fine-grain, temporal, and qualitative environmental elements. Among the web tools used, auditors rated MS Visual Oblique as the most valuable. Yet Street View tends to be rated as the most useful in measuring fine-grain features, such as levelness and condition of sidewalks. Conclusion While web-based tools do not offer a perfect substitute for on-site audits, they allow for preliminary audits to be performed accurately from remote locations, potentially saving time and cost and increasing the effectiveness of subsequent on-site visits. PMID:23247423

  14. Field Summary Report for Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington

    SciTech Connect

    L.C. Hulstrom

    2010-08-11

    This report summarizes field sampling activities conducted in support of WCH’s Remedial Investigation of Hanford Site Releases to the Columbia River. This work was conducted form 2008 through 2010. The work included preliminary mapping and measurement of Hanford Site contaminants in sediment, pore water, and surface water located in areas where groundwater upwelling were found.

  15. Field Summary Report for Remedial Investigation of Hanford Site Releases to the Coumbia River, Hanford Site, Washington

    SciTech Connect

    L.C. Hulstrom

    2010-11-10

    This report summarizes field sampling activities conducted in support of WCH’s Remedial Investigation of Hanford Site Releases to the Columbia River. This work was conducted form 2008 through 2010. The work included preliminary mapping and measurement of Hanford Site contaminants in sediment, pore water, and surface water located in areas where groundwater upwelling were found.

  16. Nonpotential magnetic fields at sites of gamma-ray flares

    NASA Technical Reports Server (NTRS)

    Hagyard, M. J.; Venkatakrishnan, P.; Smith, J. B., Jr.

    1990-01-01

    The relation between the degree of nonpotentiality of photospheric magnetic fields and the occurrence of gama-ray flares is examined to determine whether there are special signatures of the stressed fields for this type of flare. Observations of the flares in the active region of April 1984 (AR 4474) are analyzed, showing that the big flare initiated at the location on the magnetic neutral line where the field deviated the most from a potential field. The nonpotential signatures of AR 4474 are compared with those of four other regions. The results suggest that gamma-ray flares are associated with strongly nonpotential fields that extend over relatively larger lengths of the magnetic neutral line that the fields associated with flares that do not produce gamma-ray events.

  17. Nonpotential magnetic fields at sites of gamma-ray flares

    SciTech Connect

    Hagyard, M.J.; Venkatakrishnan, P.; Smith, J.B. Jr.

    1990-06-01

    The relation between the degree of nonpotentiality of photospheric magnetic fields and the occurrence of gama-ray flares is examined to determine whether there are special signatures of the stressed fields for this type of flare. Observations of the flares in the active region of April 1984 (AR 4474) are analyzed, showing that the big flare initiated at the location on the magnetic neutral line where the field deviated the most from a potential field. The nonpotential signatures of AR 4474 are compared with those of four other regions. The results suggest that gamma-ray flares are associated with strongly nonpotential fields that extend over relatively larger lengths of the magnetic neutral line that the fields associated with flares that do not produce gamma-ray events. 9 refs.

  18. Field evaluation of hazardous waste site bioassessment protocols

    SciTech Connect

    Thomas, J.M.; Cline, J.F.; Cushing, C.E.; McShane, M.C.; Rogers, J.E.; Rogers, L.E.; Simpson, J.C.; Skalski, J.R.

    1983-04-01

    The goals were: (1) determine the variability (both within and between laboratories) for the various bioassay procedures using contaminated soil samples from the Rocky Mountain Arsenal (RMA); (2) assess variability within and between plots for several assessment techniques (for sampling small mammals, plants, insects including honeybees and microarthropods) so that field studies could be designed to detect a defined biotic change; (3) establish three field plant transects which are apparently (a) contaminated, (b) appear contaminated and (c) could serve as a control; (4) assess the feasibility (in the laboratory) of using Basin F water to contaminate RMA soil artificially, and to supply information for the design of a field plot study in 1983; (5) attempt to obtain preliminary data on any promising field or laboratory bioassessment techniques not currently mentioned in the statement of work; and (6) obtain field data to assess the ecological status of RMA lakes and compare these observations to results from bioassessment testing.

  19. Nonpotential magnetic fields at sites of gamma ray flares

    NASA Technical Reports Server (NTRS)

    Hagyard, M. J.; Venkatakrishnan, P.; Smith, J. B., Jr.

    1988-01-01

    The relation between the degree of nonpotentiality of photospheric magnetic fields and the occurrence of gamma ray flares is examined. The parameter delta phi (magnetic shear) and the strength of the magnetic field intensity are used as measures of the degree of nonpotentiality, where delta phi is defined as the angular difference between the observed direction of the transverse component of the photospheric field and the direction of the potential field prescribed by the distribution of measured photospheric flux. An analysis of the great flare of April 24 to 25, 1984 is presented as an example of this technique to quantify the nonpotential characteristics of the pre-flare magnetic field. For this flare, which produced a large gamma ray event, strong shear and high field strengths prevailed over an extended length of the magnetic neutral line where the flare occurred. Moreover, the flare began near the area of strongest measured shear (89 to 90 deg). Four other flaring regions were analyzed; one of these produced a moderate gamma ray event while the other three did not produce detectable gamma rays. For all four regions the flares were located in the area where the field was not nonpotential, regardless of the class of flare. The fields of the gamma ray flares were compared with those associated with the flares without gamma rays, and little distinction was found in the degree of magnetic shear. The major difference is seen in the extent of the sheared field: for gamma ray events, the field is sheared over a longer length of the neutral line.

  20. Land reclamation on the Nevada Test Site: A field tour

    SciTech Connect

    Winkel, V.K.; Ostler, W.K.

    1993-12-31

    An all-day tour to observe and land reclamation on the Nevada Test Site was conducted in conjunction with the 8th Wildland Shrub and Arid Land Restoration Symposium. Tour participants were introduced to the US Department of Energy reclamation programs for Yucca Mountain Site Characterization Project and Treatability Studies for Soil Media (TSSM) Project. The tour consisted of several stops that covered a variety of topics and studies including revegetation by seeding, topsoil stockpile stabilization, erosion control, shrub transplanting, shrub herbivory, irrigation, mulching, water harvesting, and weather monitoring.

  1. Effects of topography and soil properties on recharge at two sites in an agricultural field

    USGS Publications Warehouse

    Delin, G.N.; Healy, R.W.; Landon, M.K.; Böhlke, J.K.

    2000-01-01

    Field experiments were conducted from 1992 to 1995 to estimate ground water recharge rates at two sites located within a 2.7-hectare agricultural field. The field lies in a sand plain setting in central Minnesota and is cropped continuously in field corn. The sites are located at a topographically high (upland) site and a topographically low (lowland) site in an effort to quantify the effects of depression focusing of recharge. Three site-specific methods were used to estimate recharge rates: well hydrograph analysis, chlorofluorocarbon age dating, and an unsaturated zone water balance. All three recharge methods indicated that recharge rates at the lowland site (annual average of all methods of 29 cm) exceeded those at the upland site (annual average of 18 cm). On an annual basis, estimates by the individual methods ranged from 12 to 44 percent of precipitation at the upland site and from 21 to 83 percent at the lowland site. The difference in recharge rates between the sites is primarily attributed to depression focusing of surface water runon at the lowland site. However, two other factors were also important: the presence of thin lamellae at the upland site, and coarser textured soils below a depth of 1.5 m at the lowland site.

  2. Field evaluation of hazardous waste site bioassessment protocols. Volume 2

    SciTech Connect

    Thomas, J.M.; Cline, J.F.; Gano, K.A.; McShane, M.C.; Rogers, J.E.; Rogers, L.E.; Simpson, J.C.; Skalski, J.R.

    1984-04-01

    The overall goal of the plan was to demonstrate that honeybees could be used in detecting likely areas of chemical pollution, to demonstrate the usefulness of microbial and plant phytoassays, and to demonstrate a relationship between laboratory derived phytotoxicity results and field observations of plant community structure and diversity. Field studies were conducted through a cooperative arrangement with the US Army arsenal in Commerce City, Colorado.

  3. Incorporating Sustainability into Site Closure - A Field Example

    NASA Astrophysics Data System (ADS)

    Austrins, L. M.; West, J.

    2013-12-01

    Long term management of former chemical production facilities can be a costly and time consuming element of site closure, however, implementation of creative measures to introduce sustainability and reduce the need for onsite presence can be successfully incorporated into the site closure process. A case study demonstrating this involves a facility located in Sarnia, Ontario, which was an active multi chemical production facility from the 1940s, until it was decommissioned and sold between 2005 and 2010. The facility consisted of 322 acres of production areas. Several elements which allowed for reduced onsite presence and lower management costs were incorporated into the site decommissioning plan, including; phased remediation planning, and selection of sustainable components as part of remediation, surface water management, and groundwater management. The sustainability and management modifications were successfully negotiated and approved by the local regulatory agency. Due to the size and complexity of the site, a holistic approach for the facility was needed and included the development of a comprehensive decision matrix. Each remediation alternative incorporated sustainable practices. Ex-situ remediation consisted of excavation of contaminated subsurface medium and consolidation at a 4.7 acre onsite soil treatment area designed specifically for the site closure process. In-situ remediation consisted of injection of amendment into the native soils using hydraulic fracture and injection. When the plant was an active operating facility, groundwater management required active pumping and groundwater treatment through a series of carbon treatment units. Active pumping has been replaced by passive hydraulic control through the use of tree plantations.

  4. Evaluation in the Field: The Need for Site Visit Standards

    ERIC Educational Resources Information Center

    Patton, Michael Quinn

    2015-01-01

    Our understanding of programs is enhanced when trained, skilled, and observant evaluators go "into the field"--the real world where programs are conducted--paying attention to what's going on, systematically documenting what they see, and reporting what they learn. The article opens by presenting and illustrating twelve reasons for…

  5. Site study plan for utilities and solid waste, Deaf Smith County Site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-06-01

    This site plan describes utilities and solid waste studies to be conducted during the characterization of the Deaf Smith County, Texas, site for the US Department of Energy's Salt Repository Project. After utilities and solid waste information needs derived from Federal, State, and local statutes and regulations and the project specifications are briefly described, the site study plan describes the study design and rationale, the field data collection procedures and equipment, and data analysis methods and application of results, the data management strategy, the schedule of field activities, the management of the study, and the study's quality assurance program. The field data collection activities are organized into programs to characterize electrical power, natural gas, communication, water, wastewater sludge, nonradiological solid waste, nonradiological hazardous waste, and low-level radiological waste. These programs include details for the collection of project needs, identification of utilities and solid waste disposal contractor capabilities, and verification of the obtained data. Utilities and solid waste field activities will begin approximately at the time of site access. Utilities and solid waste characterization will be completed within the first year of activity. 29 refs., 6 figs., 2 tabs.

  6. Form and Actuality

    NASA Astrophysics Data System (ADS)

    Bitbol, Michel

    A basic choice underlies physics. It consists of banishing actual situations from theoretical descriptions, in order to reach a universal formal construct. Actualities are then thought of as mere local appearances of a transcendent reality supposedly described by the formal construct. Despite its impressive success, this method has left major loopholes in the foundations of science. In this paper, I document two of these loopholes. One is the problem of time asymmetry in statistical thermodynamics, and the other is the measurement problem of quantum mechanics. Then, adopting a broader philosophical standpoint, I try to turn the whole picture upside down. Here, full priority is given to actuality (construed as a mode of the immanent reality self-reflectively being itself) over formal constructs. The characteristic aporias of this variety of "Copernican revolution" are discussed.

  7. Site location and crystal field of Nd3+ ions in congruent strontium barium niobate

    NASA Astrophysics Data System (ADS)

    Molina, P.; Loro, H.; Álvarez-García, S.; Bausá, L. E.; Rodriguez, E. Martín; Guillot-Noël, O.; Goldner, Ph.; Bettinelli, M.; Ghigna, P.; Solé, J. García

    2009-08-01

    The site location of Nd3+ ions in congruent strontium barium niobate (Sr0.6Ba0.4Nb2O6) has been systematically investigated by means of low-temperature optical and electron paramagnetic resonance spectroscopies. The experimental results obtained by these complementary techniques clearly indicate that Nd3+ ions are mainly located in only one of the four available cationic sites, the A2 sites, and preserving the Cs local symmetry of these host cation sites. The energy levels and g -factor value experimentally obtained by both techniques have been used to calculate the crystal field parameters for the Nd3+ ions in this A2 cationic site.

  8. Physical and chemical control of released microorganisms at field sites

    SciTech Connect

    Donegan, K.; Seidler, R.; Matyac, C.

    1991-01-01

    An important consideration in the environmental release of a genetically engineered microorganism (GEM) is the capability for reduction or elimination of GEM populations once their function is completed or if adverse environmental effects are observed. The decontamination treatments of burning and biocide application, alone and in combination with tilling, were evaluated for their ability to reduce populations of bacteria released on the phylloplane. Field plots of bush beans sprayed with the bacterium Erwinia herbicola, received the following treatments: (1) control, (2) control + till, (3) burn, (4) burn + till, (5) Kocide (cupric hydroxide), (6) Kocide + till, (7) Agri-strep (streptomycin sulfate), and (8) Agri-strept + till. Leaves and soil from the plots were sampled -1, 1, 5, 8, 12, 15, 19, and 27 days after application of the decontamination treatments. Burning produced a significant and persistent reduction in the number of bacteria whereas tilling, alone or in combination with the biocide treatments, stimulated a significant and persistent reduction in the number of bacteria, whereas tilling, alone or in combination with the biocide treatments, stimulated a significant increase in bacterial populations that persisted for several weeks.

  9. Geological characterization of remote field sites using visible and infrared spectroscopy: Results from the 1999 Marsokhod field test

    USGS Publications Warehouse

    Johnson, J. R.; Ruff, S.W.; Moersch, J.; Roush, T.; Horton, K.; Bishop, J.; Cabrol, N.A.; Cockell, C.; Gazis, P.; Newsom, Horton E.; Stoker, C.

    2001-01-01

    Upcoming Mars Surveyor lander missions will include extensive spectroscopic capabilities designed to improve interpretations of the mineralogy and geology of landing sites on Mars. The 1999 Marsokhod Field Experiment (MFE) was a Mars rover simulation designed in part to investigate the utility of visible/near-infrared and thermal infrared field spectrometers to contribute to the remote geological exploration of a Mars analog field site in the California Mojave Desert. The experiment simultaneously investigated the abilities of an off-site science team to effectively analyze and acquire useful imaging and spectroscopic data and to communicate efficiently with rover engineers and an on-site field team to provide meaningful input to rover operations and traverse planning. Experiences gained during the MFE regarding effective communication between different mission operation teams will be useful to upcoming Mars mission teams. Field spectra acquired during the MFE mission exhibited features interpreted at the time as indicative of carbonates (both dolomitic and calcitic), mafic rocks and associated weathering products, and silicic rocks with desert varnish-like coatings. The visible/near-infrared spectra also suggested the presence of organic compounds, including chlorophyll in one rock. Postmission laboratory petrologic and spectral analyses of returned samples confirmed that all rocks identified as carbonates using field measurements alone were calc-silicates and that chlorophyll associated with endolithic organisms was present in the one rock for which it was predicted. Rocks classified from field spectra as silicics and weathered mafics were recognized in the laboratory as metamorphosed monzonites and diorite schists. This discrepancy was likely due to rock coatings sampled by the field spectrometers compared to fresh rock interiors analyzed petrographically, in addition to somewhat different surfaces analyzed by laboratory thermal spectroscopy compared to field

  10. Savannah River Site Experiences in In Situ Field Measurements of Radioactive Materials

    SciTech Connect

    Moore, F.S.

    1999-10-07

    This paper discusses some of the field gamma-ray measurements made at the Savannah River Site, the equipment used for the measurements, and lessons learned during in situ identification and characterization of radioactive materials.

  11. Field site investigation: Effect of mine seismicity on groundwater hydrology

    SciTech Connect

    Ofoegbu, G.I.; Hsiung, S.; Chowdhury, A.H.; Philip, J.

    1995-04-01

    The results of a field investigation on the groundwater-hydrologic effect of mining-induced earthquakes are presented in this report. The investigation was conducted at the Lucky Friday Mine, a silver-lead-zinc mine in the Coeur d`Alene Mining District of Idaho. The groundwater pressure in sections of three fracture zones beneath the water table was monitored over a 24-mo period. The fracture zones were accessed through a 360-m-long inclined borehole, drilled from the 5,700 level station of the mine. The magnitude, source location, and associated ground motions of mining-induced seismic events were also monitored during the same period, using an existing seismic instrumentation network for the mine, augmented with additional instruments installed specifically for the project by the center for Nuclear Waste Regulatory Analyses (CNWRA). More than 50 seismic events of Richter magnitude 1.0 or larger occurred during the monitoring period. Several of these events caused the groundwater pressure to increase, whereas a few caused it to decrease. Generally, the groundwater pressure increased as the magnitude of seismic event increased; for an event of a given magnitude, the groundwater pressure increased by a smaller amount as the distance of the observation point from the source of the event increased. The data was examined using regression analysis. Based on these results, it is suggested that the effect of earthquakes on groundwater flow may be better understood through mechanistic modeling. The mechanical processes and material behavior that would need to be incorporated in such a model are examined. They include a description of the effect of stress change on the permeability and water storage capacity of a fracture rock mass; transient fluid flow; and the generation and transmission of seismic waves through the rock mass.

  12. FIELD MEASUREMENT OF VAPOR INTRUSION RATES AT A PCE SITE (ABSTRACT ONLY)

    EPA Science Inventory

    A field study was performed to evaluate vapor intrusion (VI) of tetrachloroethylene (PCE) and other chlorinated solvents at a commercial retail site in Dallas, TX. The building is approximately 40 years old and once housed a dry cleaning operation. Results from an initial site ch...

  13. Site Study Plan for background environmental radioactivity, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-06-01

    The Background Environmental Radioactivity Site Study Plan describes a field program consisting of an initial radiological survey and a radiological sampling program. The field program includes measurement of direct radiation and collection and analysis of background radioactivity samples of air, precipitation, soil, water, milk, pasture grass, food crops, meat, poultry, game, and eggs. The plan describes for each study: the need for the study, the study design, data management and use, schedule of proposed activities, and quality assurance requirements. These studies will provide data needed to satisfy requirements contained in, or derived from, the Salt Repository Project (SRP) Requirements Document. 50 refs., 11 figs., 7 tabs.

  14. Extensive management of field margins enhances their potential for off-site soil erosion mitigation.

    PubMed

    Ali, Hamada E; Reineking, Björn

    2016-03-15

    Soil erosion is a widespread problem in agricultural landscapes, particularly in regions with strong rainfall events. Vegetated field margins can mitigate negative impacts of soil erosion off-site by trapping eroded material. Here we analyse how local management affects the trapping capacity of field margins in a monsoon region of South Korea, contrasting intensively and extensively managed field margins on both steep and shallow slopes. Prior to the beginning of monsoon season, we equipped a total of 12 sites representing three replicates for each of four different types of field margins ("intensive managed flat", "intensive managed steep", "extensive managed flat" and "extensive managed steep") with Astroturf mats. The mats (n = 15/site) were placed before, within and after the field margin. Sediment was collected after each rain event until the end of the monsoon season. The effect of management and slope on sediment trapping was analysed using linear mixed effects models, using as response variable either the sediment collected within the field margin or the difference in sediment collected after and before the field margin. There was no difference in the amount of sediment reaching the different field margin types. In contrast, extensively managed field margins showed a large reduction in collected sediment before and after the field margins. This effect was pronounced in steep field margins, and increased with the size of rainfall events. We conclude that a field margin management promoting a dense vegetation cover is a key to mitigating negative off-site effects of soil erosion in monsoon regions, particularly in field margins with steep slopes.

  15. On-site fuel cell field test support program. Annual report Jul 81-Jun 82

    SciTech Connect

    Staniunas, J.W.; Merten, G.P.

    1982-09-01

    United continued this past year to assist the utilities and the Gas Research Institute in the review and selection of sites for data monitoring. Each of these sites will be instrumented and its energy requirements monitored and analyzed for one year prior to the selection of 40 Kilowatt fuel cell field test sites. Analyses in support of the selection of sites for instrumentation continued to show that many building sectors offered considerable market potential. These sectors include nursing home, health club, restaurant, industrial, hotel/motel and apartment.

  16. Field sampling and selecting on-site analytical methods for explosives in soil

    SciTech Connect

    Crockett, A.B.; Craig, H.D.; Jenkins, T.F.; Sisk, W.E.

    1996-12-01

    A large number of defense-related sites are contaminated with elevated levels of secondary explosives. Levels of contamination range from barely detectable to levels above 10% that need special handling because of the detonation potential. Characterization of explosives-contaminated sites is particularly difficult because of the very heterogeneous distribution of contamination in the environment and within samples. To improve site characterization, several options exist including collecting more samples, providing on-site analytical data to help direct the investigation, compositing samples, improving homogenization of the samples, and extracting larger samples. This publication is intended to provide guidance to Remedial Project Managers regarding field sampling and on-site analytical methods for detecting and quantifying secondary explosive compounds in soils, and is not intended to include discussions of the safety issues associated with sites contaminated with explosive residues.

  17. Field Instructors' Perceptions of Evidence-Based Practice in BSW Field Placement Sites

    ERIC Educational Resources Information Center

    Wiechelt, Shelly A.; Ting, Laura

    2012-01-01

    This exploratory study surveyed 17 BSW-level field instructors on their experience, beliefs, and perceived self-efficacy regarding evidence-based practice (EBP). The authors conducted focus groups concerning EBP in participants' agencies and with BSW students under their supervision. Results indicate that although they felt positive toward EBP and…

  18. Characterization of instrumented sites for the onsite fuel-cell field-test project. Volume 5. Topical report, 1983-1985

    SciTech Connect

    Racine, W.C.; Campillo, C.J.

    1986-11-01

    During the site-selection phase of the Onsite Fuel-Cell Field Test, nearly one hundred sites throughout the U.S. were each instrumented with a standard data-acquisition system (DAS) to collect hourly electrical and thermal data for one year. Seventy of those sites are included in the report. Each site's electrical and thermal systems were instrumented including ambient temperature, electrical demands, building gas usage, and other parameters necessary to calculate building thermal loads. Multifamily residential, commercial, and light industrial sites were instrumented. Approximately twenty market sectors were represented including restaurants, hospitals, hotels, apartments, health clubs, nursing homes, and food-processing plants. The primary use of the data was to determine site compatibility for the installation of 40-kW fuel-cell power plants. However, the collected energy data and site-specific information summarized in the comprehensive report may also be useful for other applications such as market characterization and simulation of new or improved energy-utilization equipment in actual sites. This volume focuses on photographic laboratories, restaurants, schools, telephone communications, trucking terminals, and water-processing plants.

  19. Characterization of instrumented sites for the Onsite Fuel-Cell Field-Test project. Volume 2. Topical report, 1983-1985

    SciTech Connect

    Racine, W.C.; Campillo, C.J.

    1986-11-01

    During the site selection phase of the Onsite Fuel-Cell Field Test, nearly one hundred sites throughout the U.S. were each instrumented with a standard data-acquisition system (DAS) to collect hourly electrical and thermal data for one year. Seventy of those sites are included in the report. Each site's electrical and thermal systems were instrumented including ambient temperature, electrical demands building gas usage, and other parameters which were necessary to calculate building thermal loads. Multifamily residential, commercial and light industrial sites were instrumented. Approximately twenty market sectors were represented including restaurants, hospitals, hotels, apartments, health clubs, nursing homes, and food-processing plants. The primary use of the data was to determine site compatibility for the installation of 40-kW fuel-cell power plants. However, the collected energy data and site-specific information summarized in this comprehensive report may also be useful for other applications such as market characterization, and simulation of new or improved energy-utilization equipment in actual sites. This volume focuses on food processors, groceries, health clubs, and hospitals.

  20. Characterization of instrumented sites for the Onsite Fuel-Cell Field-Test project. Volume 1. Topical report, 1983-1985

    SciTech Connect

    Racine, W.C.; Campillo, C.J.

    1986-11-01

    During the site selection phase of the Onsite Fuel-Cell Field Test, nearly one hundred sites throughout the U.S. were each instrumented with a standard data-acquisition system (DAS) to collect hourly electrical and thermal data for one year. Seventy of those sites are included in the report. Each site's electrical and thermal systems were instrumented including ambient temperature, electrical demands building gas usage, and other parameters which were necessary to calculate building thermal loads. Multifamily residential, commercial and light industrial sites were instrumented. Approximately twenty market sectors were represented including restaurants, hospitals, hotels, apartments, health clubs, nursing homes, and food-processing plants. The primary use of the data was to determine site compatibility for the installation of 40-kW fuel-cell power plants. However, the collected energy data and site-specific information summarized in the comprehensive report may also be useful for other applications such as market characterization, and simulation of new or improved energy-utilization equipment in actual sites. This volume focuses on apartments, bakeries, bowling alleys, and dormitories.)

  1. Characterization of instrumented sites for the Onsite Fuel-Cell Field-Test project. Executive Summary. Topical report, 1983-1985

    SciTech Connect

    Racine, W.C.; Campillo, C.J.

    1986-11-01

    During the site selection phase of the Onsite Fuel-Cell Field Test, nearly one hundred sites throughout the U.S. were each instrumented with a standard data-acquisition system (DAS) to collect hourly electrical and thermal data for one year. Seventy of those sites are included in the report. Each site's electrical and thermal systems were instrumented including ambient temperature, electrical demands building gas usage, and other parameters which were necessary to calculate building thermal loads. Multifamily residential, commercial and light industrial sites were instrumented. Approximately twenty market sectors were represented including restaurants, hospitals, hotels, apartments, health clubs, nursing homes, and food-processing plants. The primary use of the data was to determine site compatibility for the installation of 40 kW fuel cell power plants. However, the collected energy data and site-specific information summarized in the comprehensive report may also be useful for other applications such as market characterization, and simulation of new or improved energy utilization equipment in actual sites.

  2. Characterization of instrumented sites for the onsite fuel-cell field-test project. Volume 4. Topical report, 1983-1985

    SciTech Connect

    Racine, W.C.; Campillo, C.J.

    1986-11-01

    During the site-selection phase of the Onsite Fuel-Cell Field Test, nearly one hundred sites throughout the U.S. were each instrumented with a standard data-acquisition system (DAS) to collect hourly electrical and thermal data for one year. Seventy of those sites are included in the report. Each site's electrical and thermal systems were instrumented including ambient temperature, electrical demands, building gas usage, and other parameters necessary to calculate building thermal loads. Multifamily residential, commercial, and light industrial sites were instrumented. Approximately twenty market sectors were represented including restaurants, hospitals, hotels, apartments, health clubs, nursing homes, and food-processing plants. The primary use of the data was to determine site compatibility for the installation of 40-kW fuel-cell power plants. However, the collected energy data and site-specific information summarized in this comprehensive report may also be useful for other applications such as market characterization and simulation of new or improved energy-utilization equipment in actual sites. This volume covers metal-plating facilities, nurseries, nursing homes, office buildings and other industrial applications.

  3. Technical procedures for implementation of acoustics site studies, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-09-01

    The purpose and scope of the technical procedure for processing data from the tethered meteorological system are covered. Definitions, interfaces, and concurrent data needs are also addressed. This technical procedure describes how to control, organize, verify, and archive tethered meteorological system data. These data will be received at the processing location from the field measurement location and are part of the characterization of the Deaf Smith County Site, Texas for the salt repository program. These measurements will be made in support of the sound propagation study and are a result of environmental data requirements for acoustics. 6 refs., 15 figs., 5 tabs.

  4. Traffic Management Advisor: Iterative Field Development and Assessment at Multiple Sites

    NASA Technical Reports Server (NTRS)

    Sanford, Beverly D.; Lee, Katharine K.; Harwood, Kelly; Denery, Dallas G. (Technical Monitor)

    1995-01-01

    Previous studies have demonstrated the necessity of involving users in the development of automation aids, especially for complex domains such as air traffic control (ATC). Traditional development only demanded a single field test to validate a completed system, but a more iterative combination of development and assessment ensures that the technology meets the requirements of its application domain. Exposure across an adequate spectrum of field users is also required during development, and the use of multiple development sites provides an opportunity to consider individual facility cultures as they relate to implementation strategies. The development of the Center/TRACON Automation System (CTAS) Traffic Management Advisor (TMA) at the Denver and Dallas ATC facilities demonstrates successful iterative development and assessment at multiple field sites. The use of field development changes the nature of assessment. As development progresses, periodic assessments are required to validate that system development is progressing along an appropriate track. In the development of the TMA, assessments were performed based on software in the field, and input from traffic managers was analyzed and incorporated into subsequent releases of the TMA, to be reassessed in the field. This has led to a tool with operational suitability and broad user acceptance. Assessment at multiple sites provides a more generalizable perspective that allows the production of a system that is both generic enough to be used at different sites and tailored enough to be of use at any site. In addition to providing a better understanding of specific facility requirements, the use of multiple assessment sites in the development of TMA has provided an opportunity to consider individual facility operations, procedures and cultures as they relate to development and implementation strategies.

  5. Rocketdyne division environmental monitoring annual report, Santa Susana Field Laboratory, De Soto, and Canoga Sites, 1990

    SciTech Connect

    none,

    1991-06-20

    This annual report discuses environmental monitoring at three manufacturing and test operations sites operated in the Southern California area by the Rocketdyne Division of Rockwell International Corporation. These are identified as the Santa Susana Field Laboratory (SSFL.), the De Soto site, and the Canoga site. These sites have been used for manufacturing, R&D, engineering, and testing in a broad range of technical fields, primarily rocket engine propulsion and nuclear reactor technology. The De Soto and Canoga sites are essentially light industry with some laboratory-scale R&D and have little potential impact on the environment. The SSFL site, because of its large size (2,668 acres), warranted comprehensive monitoring to assure protection of the environment. The purpose of this report is to present information on environmental and effluent monitoring primarily for the regulatory agencies involved in controlling operations with nuclear and radioactive materials, i.e., the U.S. DOE, the U.S. Nuclear Regulatory Commission (NRC), and the California State Department of Health Services (DHS), Radiologic Health Branch (RHB). For that reason, information concentrates on Area IV at SSFL as this is the site of the former nuclear operations. While the major realm of interest is radiological, this report also includes some discussion of nonradiological monitoring at SSFL

  6. Research Highlights and Recent Enhancements at the NEES@UCSB Permanently Instrumented Field Sites

    NASA Astrophysics Data System (ADS)

    Steidl, J. H.; Hegarty, P.; Seale, S. H.; Lamere, T.; Stinson, E.; Wojcik, K.

    2012-12-01

    The NEES@UCSB facility consists of experimental facilities and cyber infrastructure for active testing and passive earthquake monitoring at instrumented geotechnical field sites. There have been a number of facility enhancements to both the experimental facilities and the cyber infrastructure for facilitating research at the sites and access to the data they produce. Through both the maintenance and operations and the NEES Research program funding sources, the scope of monitoring at the field sites continues to expand. A permanent cross-hole source and sensor array has been installed at both the Wildlife Liquefaction Array (WLA) and at the Garner Valley Downhole Array (GVDA) field sites. This enhancement provides daily measurements of shear-wave velocity and automated post-earthquake observations of velocity to examine soil modulus reduction and recovery. After a very large event, where nonlinear soil behavior is expected, cross-hole hammer source time intervals are as short as 5 minutes. While waiting for larger earthquakes to occur, the daily cross-hole hammer tests are providing interesting data on shear-wave velocity changes with seasonal water table height. Testing of a small reconfigurable structure at both the WLA and GVDA sites was conducted using the NEES@UCLA mobile shakers. The structure, which is a smaller version of a permanent structure at GVDA, has been left at the GVDA site and can be used for future experiments or site instrumentation enhancements. The large soil-foundation-interaction structure at GVDA has a 1D shaker mounted under its roof slab. This shaker runs nightly and the data provide insight into the influence of environmental conditions on the response of the structure. At WLA, additional sensors have been installed in a dense Shape Accelerometer Array (SAA). Each of the seven arrays contain 24 3-component MEMS accelerometers at approximately 0.3 meter spacing that span the upper 8 meters of the site, from above to below the liquefiable

  7. Effective removal of field-emitting sites from metallic surfaces by dry ice cleaning

    SciTech Connect

    Dangwal, Arti; Mueller, Guenter; Reschke, Detlef; Floettmann, Klaus; Singer, Xenia

    2007-08-15

    Systematic results of the field emission properties of polycrystalline copper and niobium and single-crystal Nb are reported. Dry ice cleaning (DIC) is found to suppress enhanced field emission from metallic surfaces. The cleaning effect on the emitting sites was investigated by means of field emission scanning microscopy up to fields of 250 MV/m and high-resolution scanning electron microscopy with energy dispersive x-ray analysis. The number density of emitters at given fields was drastically reduced by dry ice cleaning. Current-voltage measurements and derived Fowler-Nordheim parameters are partially discussed with respect to the morphology and impurity content of localized emitters. No emission from grain boundaries on large-grain Nb samples was observed. The microscopy results prove the effective removal of field-emitting particulates down to 400 nm as well as the partial smoothing of surface protrusions by DIC.

  8. Health system reform and the role of field sites based upon demographic and health surveillance.

    PubMed Central

    Tollman, S. M.; Zwi, A. B.

    2000-01-01

    Field sites for demographic and health surveillance have made well-recognized contributions to the evaluation of new or untested interventions, largely through efficacy trials involving new technologies or the delivery of selected services, e.g. vaccines, oral rehydration therapy and alternative contraceptive methods. Their role in health system reform, whether national or international, has, however, proved considerably more limited. The present article explores the characteristics and defining features of such field sites in low-income and middle-income countries and argues that many currently active sites have a largely untapped potential for contributing substantially to national and subnational health development. Since the populations covered by these sites often correspond with the boundaries of districts or subdistricts, the strategic use of information generated by demographic surveillance can inform the decentralization efforts of national and provincial health authorities. Among the areas of particular importance are the following: making population-based information available and providing an information resource; evaluating programmes and interventions; and developing applications to policy and practice. The question is posed as to whether their potential contribution to health system reform justifies arguing for adaptations to these field sites and expanded investment in them. PMID:10686747

  9. Site-selected doping in silicon nanowires by an external electric field.

    PubMed

    Wu, Fang; Kan, Erjun; Wu, Xiaojun

    2011-09-01

    The properties of dopant-related defects in silicon nanowires are key characteristics in semiconductive devices. Our first-principles calculations predicted that the preferred doping sites of B and P atoms in hydrogen-passivated silicon nanowires have opposite distribution behavior under electric field, suggesting a steady intrinsic p-n junction can be spontaneously formed in (B and P) codoped silicon nanowires.

  10. Field fracturing multi-sites project. Annual report, August 1, 1995--July 31, 1996

    SciTech Connect

    1996-12-31

    The objective of the Field Fracturing Multi-Sites Project (M-Site) is to conduct experiments to definitively determine hydraulic fracture dimensions using remote well and treatment well diagnostic techniques. In addition, experiments are to be conducted to provide data that will resolve significant unknowns with regard to hydraulic fracture modeling, fracture fluid rheology and fracture treatment design. These experiments will be supported by a well-characterized subsurface environment, as well as surface facilities and equipment conducive to acquiring high-quality data. The primary Project goal is to develop a fully characterized, tight reservoir-typical, field-scale hydraulic fracturing test site to diagnose, characterize, and test hydraulic fracturing technology and performance. It is anticipated that the research work being conducted by the multi-disciplinary team of GRI and DOE contractors will lead to the development of a commercial fracture mapping tool/service.

  11. Oscillatory Hydraulic Tomography at the Field Scale: Boise Hydrogeophysical Research Site

    NASA Astrophysics Data System (ADS)

    Lim, D.; Barrash, W.; Cardiff, M. A.

    2015-12-01

    The use of sinusoidal or periodic testing for field-scale tomography of aquifer parameters (conductivity / storativity) is a novel, minimally-invasive method for aquifer characterization between boreholes. Previous results have demonstrated the effectiveness of this method, which we name Oscillatory Hydraulic Tomography (OHT), through both numerical and laboratory experiments. However, implementation and analysis of field-scale OHT testing has not been achieved to-date, and thus the technique remains unproven for application in real-world aquifers. We present an evaluation of OHT at the field scale here through application at the Boise Hydrogeophysical Research Site (BHRS), a field-scale (~20m diameter x 20m thickness) research site. Through Bayesian inversion, we assess issues such as data quality impacts and resolution of obtained tomographic images. We discuss issues associated with both data collection and data processing, and based on our experiences suggest a workflow for OHT performance at other field sites. The advantages of OHT, relative to "traditional" hydraulic tomography with constant rate pumping tests, include the ability to test across a range of stimulation frequencies (obtaining increased heterogeneity information), very high signal-to-noise ratios. Additionally, we examine the impact of nonlinear effects - such as water table boundary conditions - and their impact on OHT analysis algorithms.

  12. Field vapor extraction test and long-term monitoring at a PCE contaminated site.

    PubMed

    Chai, J-C; Miura, N

    2004-07-01

    The results of a field investigation, vapor extraction tests, and long-term monitoring at a PCE-contaminated site in Saga, Japan, are reported. The field investigation indicated that PCE likely was trapped in a surface clayey sand layer (vadose zone), and soil vapor extraction (SVE) was adopted as the remediation approach. The field test results the effectiveness of SVE in removing volatile organic compounds (VOCs) from contaminated sites. For the case where the radius of influence for an extraction well was 15-20 m, the blower capacity had no obvious effect on the radius of influence possibly due to the short circuiting of air from the ground surface. However, the maximum negative pressure (difference between vapor pressure and ambient pressure) in the extraction well was approximately proportional to blower capacity for the range of blower capacities tested. The long-term monitoring results indicate that PCE concentration varied seasonably, and temperature and rainfall are two of the influencing factors.

  13. Performance of in situ chemical oxidation field demonstrations at DOE sites

    SciTech Connect

    Cline, S.R.; West, O.R.; Siegrist, R.L.; Holden, W.L.

    1997-04-01

    Researchers at the Oak Ridge National Laboratory (ORNL) have been investigating the use of in situ chemical oxidation to remediate organic contaminants (VOCs, SVOCs, and PCBs) in soils and groundwater at the laboratory and field scales. Field scale design parameters (e.g., oxidant loading rates and oxidant delivery techniques) are often dictated by site conditions (e.g., soil properties and initial contaminant concentrations). Chemical destruction of organic compounds can be accomplished using a variety of oxidants. Recent research has involved field scale in situ chemical oxidation demonstrations using H{sub 2}O{sub 2} and KMnO{sub 4} in conjunction with soil mixing as the oxidant delivery mechanism. A description of some of these fields activities and future field-scale work is presented here.

  14. Site characterization techniques used at a low-level waste shallow land burial field demonstration facility

    SciTech Connect

    Davis, E.C.; Boegly, W.J. Jr.; Rothschild, E.R.; Spalding, B.P.; Vaughan, N.D.; Haase, C.S.; Huff, D.D.; Lee, S.Y.; Walls, E.C.; Newbold, J.D.

    1984-07-01

    The Environmental Sciences Division of the Oak Ridge National Laboratory has been investigating improved shallow land burial technology for application in the humd eastern United States. As part of this effort, a field demonstration facility (Engineered Test Facility, or ETF) has been established in Solid Waste Storage Area 6 for purposes of investigatig the ability of two trench treatments (waste grouting prior to cover emplacement and waste isolation with trench liners) to prevent water-waste contact and thus minimize waste leaching. As part of the experimental plan, the ETF site has been characterized for purposes of constructing a hydrologic model. Site characterization is an extremely important component of the waste disposal site selection process; during these activities, potential problems, which might obviate the site from further consideration, may be found. This report describes the ETF site characterization program and identifies and, where appropriate, evaluates those tests that are of most value in model development. Specific areas covered include site geology, soils, and hydrology. Each of these areas is further divided into numerous subsections, making it easy for the reader to examine a single area of interest. Site characterization is a multidiscipliary endeavor with voluminous data, only portions of which are presented and analyzed here. The information in this report is similar to that which will be required of a low-level waste site developer in preparing a license application for a potential site in the humid East, (a discussion of licensing requirements is beyond its scope). Only data relevant to hydrologic model development are included, anticipating that many of these same characterization methods will be used at future disposal sites with similar water-related problems.

  15. Quantitative, directional measurement of electric field heterogeneity in the active site of ketosteroid isomerase.

    PubMed

    Fafarman, Aaron T; Sigala, Paul A; Schwans, Jason P; Fenn, Timothy D; Herschlag, Daniel; Boxer, Steven G

    2012-02-01

    Understanding the electrostatic forces and features within highly heterogeneous, anisotropic, and chemically complex enzyme active sites and their connection to biological catalysis remains a longstanding challenge, in part due to the paucity of incisive experimental probes of electrostatic properties within proteins. To quantitatively assess the landscape of electrostatic fields at discrete locations and orientations within an enzyme active site, we have incorporated site-specific thiocyanate vibrational probes into multiple positions within bacterial ketosteroid isomerase. A battery of X-ray crystallographic, vibrational Stark spectroscopy, and NMR studies revealed electrostatic field heterogeneity of 8 MV/cm between active site probe locations and widely differing sensitivities of discrete probes to common electrostatic perturbations from mutation, ligand binding, and pH changes. Electrostatic calculations based on active site ionization states assigned by literature precedent and computational pK(a) prediction were unable to quantitatively account for the observed vibrational band shifts. However, electrostatic models of the D40N mutant gave qualitative agreement with the observed vibrational effects when an unusual ionization of an active site tyrosine with a pK(a) near 7 was included. UV-absorbance and (13)C NMR experiments confirmed the presence of a tyrosinate in the active site, in agreement with electrostatic models. This work provides the most direct measure of the heterogeneous and anisotropic nature of the electrostatic environment within an enzyme active site, and these measurements provide incisive benchmarks for further developing accurate computational models and a foundation for future tests of electrostatics in enzymatic catalysis.

  16. HT to HTO conversion and field experiments near Darlington Nuclear Power Generating Station (DNPGS) site.

    PubMed

    Kim, S B; Stuart, M; Bredlaw, M; Festarini, A; Beaton, D

    2014-06-01

    The Canadian input parameters related to tritiated hydrogen gas (HT) used in tritium dose models are currently based on experiments performed at the Chalk River Laboratories (CRL) site in 1986, 1987 and 1994. There is uncertainty in how well other sites experiencing atmospheric HT releases are represented by these data. In order to address this uncertainty, HT to HTO conversion factors were evaluated at different locations near the Darlington Nuclear Power Generating Station (DNPGS) site using various experimental approaches. These were D2 gas exposure chamber experiments, atmospheric tritium measurements, and HTO and OBT measurements in vegetation and soil. In addition to these field experiments, chamber experiments were conducted using HT gas on field soil samples. The suggested Canadian input parameters for atmospheric tritium releases estimate the total fraction of HT oxidized in air and in soil, at the site, to be up to a maximum of 2.4%. Based on the more limited data obtained near DNPGS in early spring, this fraction would likely be closer to 0.5%. The result suggests that current parameters provide a conservative estimate for the DNPGS site.

  17. Field screening at petroleum contaminated sites: A tool to save time, money

    SciTech Connect

    Hood, G.M.; Pucel, P.G.; Allee, P.

    1998-01-01

    The most expensive part of an environmental assessment is often lab services. Control of these costs while still collecting adequate data to assess a site is sometimes the difference between solvency and bankruptcy, especially for small companies. Fortunately, the use of field screening techniques can significantly reduce the quantity of samples going to the laboratory for analysis, thus controlling overall project costs. Chemical and Environmental Consultants, Inc. (CEC) has been field evaluating a rapid, widely applicable method for field screening petroleum contaminated soils and wastes for SVOCs. The method is similar in application to US EPA Method 418.1 and allows for the field screening of soil and waste samples in about 10 minutes. The method uses fluorescence spectroscopy analysis of a solvent extract of the soil or waste sample.

  18. Changes in contaminant mass discharge from DNAPL source mass depletion: evaluation at two field sites.

    PubMed

    Brooks, Michael C; Wood, A Lynn; Annable, Michael D; Hatfield, Kirk; Cho, Jaehyun; Holbert, Charles; Rao, P Suresh C; Enfield, Carl G; Lynch, Kira; Smith, Richard E

    2008-11-14

    Changes in contaminant fluxes resulting from aggressive remediation of dense nonaqueous phase liquid (DNAPL) source zone were investigated at two sites, one at Hill Air Force Base (AFB), Utah, and the other at Ft. Lewis Military Reservation, Washington. Passive Flux Meters (PFM) and a variation of the Integral Pumping Test (IPT) were used to measure fluxes in ten wells installed along a transect down-gradient of the trichloroethylene (TCE) source zone, and perpendicular to the mean groundwater flow direction. At both sites, groundwater and contaminant fluxes were measured before and after the source-zone treatment. The measured contaminant fluxes (J; ML(-2)T(-1)) were integrated across the well transect to estimate contaminant mass discharge (M(D); MT(-1)) from the source zone. Estimated M(D) before source treatment, based on both PFM and IPT methods, were approximately 76 g/day for TCE at the Hill AFB site; and approximately 640 g/day for TCE, and approximately 206 g/day for cis-dichloroethylene (DCE) at the Ft. Lewis site. TCE flux measurements made 1 year after source treatment at the Hill AFB site decreased to approximately 5 g/day. On the other hand, increased fluxes of DCE, a degradation byproduct of TCE, in tests subsequent to remediation at the Hill AFB site suggest enhanced microbial degradation after surfactant flooding. At the Ft. Lewis site, TCE mass discharge rates subsequent to remediation decreased to approximately 3 g/day for TCE and approximately 3 g/day for DCE approximately 1.8 years after remediation. At both field sites, PFM and IPT approaches provided comparable results for contaminant mass discharge rates, and show significant reductions (>90%) in TCE mass discharge as a result of DNAPL mass depletion from the source zone.

  19. Polarized magnetic field fluctuations at the Apollo 15 site - Possible regional influence on lunar induction

    NASA Technical Reports Server (NTRS)

    Schubert, G.; Smith, B. F.; Colburn, D. S.; Sonett, C. P.; Schwartz, K.

    1974-01-01

    High-frequency (5 to 40 millihertz) induced lunar magnetic fields, observed at the Apollo 15 site near the southeastern boundary of Mare Imbrium and the southwestern boundary of Mare Serenitatis, show a strong tendency toward linear polarization in a direction radial to the Imbrium basin and circumferential to the Serenitatis basin, a property that could be indicative of a possible regional influence on the induction.

  20. Absence of the hyperfine magnetic field at the Ru site in ferromagnetic rare-earth intermetallics

    SciTech Connect

    Coffey, D.; DeMarco, M.; Ho, P. C.; Maple, M. B.; Sayles, T.; Lynn, J. W.; Huang, Q.; Toorongian, S.; Haka, M.

    2010-05-01

    The Moessbauer effect (ME) is frequently used to investigate magnetically ordered systems. One usually assumes that the magnetic order induces a hyperfine magnetic field, B{sub hyperfine}, at the ME active site. This is the case in the ruthenates, where the temperature dependence of B{sub hyperfine} at {sup 99}Ru sites tracks the temperature dependence of the ferromagnetic or antiferromagnetic order. However this does not happen in the rare-earth intermetallics, GdRu{sub 2} and HoRu{sub 2}. Specific heat, magnetization, magnetic susceptibility, Moessbauer effect, and neutron diffraction have been used to study the nature of the magnetic order in these materials. Both materials are found to order ferromagnetically at 83.1 and 15.3 K, respectively. Despite the ferromagnetic order of the rare-earth moments in both systems, there is no evidence of a correspondingly large B{sub hyperfine} in the Moessbauer spectrum at the Ru site. Instead the measured spectra consist of a narrow peak at all temperatures which points to the absence of magnetic order. To understand the surprising absence of a transferred hyperfine magnetic field, we carried out ab initio calculations which show that spin polarization is present only on the rare-earth site. The electron spin at the Ru sites is effectively unpolarized and, as a result, B{sub hyperfine} is very small at those sites. This occurs because the 4d Ru electrons form broad conduction bands rather than localized moments. These 4d conduction bands are polarized in the region of the Fermi energy and mediate the interaction between the localized rare-earth moments.

  1. Making the Case for Field Trips: What Research Tells Us and What Site Coordinators Have to Say

    ERIC Educational Resources Information Center

    Nabors, Martha L.; Edwards, Linda Carol; Murray, R. Kent

    2009-01-01

    This article presents the findings from a national survey of field trip sites. It also addresses the positive instructional impact of field trips and focuses on 5 major components of the field trip experience. In addition, the article presents recommendations and suggestions for positive field trip experiences.

  2. Site 1 field testing for cooling-water treatment. Final report

    SciTech Connect

    Litherland, S.T.; Owen, M.L.; Scholl, F.A.; Kamas, J.W.; Nassos, P.A.

    1985-06-01

    The Electric Power Research Institute is sponsoring a three phase research project to develop a design and operating methodology for recirculating cooling water systems at high concentration factors. To expand the available data base for cooling water systems at high concentration factors, a portable field test unit (FTU) has been designed and fabricated for operation at sites with different makeup water qualities. For a ten month period during 1981, the FTU was operated at the first site, Comanche Generating Station in Pueblo, Colorado. During the field testing, several cooling water treatment options were used to increase the concentration factor for operating the FTU. These water treatment options included: (1) sulfuric acid addition for alkalinity control; (2) lime-soda makeup softening; (3) lime-soda sidestream softening; (4) combined lime-soda makeup and sidestream softening; and (5) inhibitor addition for gypsum scale control. The purpose of this report is to present a detailed discussion of all Site 1 field test activities, including FTU operation and data interpretation and analyses. 11 refs., 68 figs., 70 tabs.

  3. Field Summary Report for Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington, Collection of Surface Water, River Sediments, and Island Soils

    SciTech Connect

    L. C. Hulstrom

    2009-09-28

    This report has been prepared in support of the remedial investigation of Hanford Site Releases to the Columbia River and describes the 2008/2009 data collection efforts. This report documents field activities associated with collection of sediment, river water, and soil in and adjacent to the Columbia River near the Hanford Site and in nearby tributaries.

  4. Sample Characterization of FIDO-2000 and FIDO-2002 Blind Field Test Sites by an APXS Instrument

    NASA Astrophysics Data System (ADS)

    Economou, T. E.

    2002-12-01

    The Mars Rover Explorer (MER) Project conducted in the past few years two major blind field test that involved the Field Integrated Design and Operations (FIDO) rover, with a payload not quite, but close to the real MER mission flight payload. Since the APXS and the MB spectrometer cannot operate properly in the Earth's atmosphere, a representative variety of rocks and soil samples from designated "landing" sites were collected and sent to the respective laboratories for analyses with these two instruments. During the field tests, the data from FIDO instruments, together with the appropriate data from the APXS and MB spectrometers, which, according to the site operators opinion, most closely resembled the real analyzed samples, were transmitted to the control room at JPL for target evaluation. The APXS analyzed both, the natural side and the fresh cut side, of most of the rocks that were made available. By comparing the analytical results from both sides, it was possible to clearly detect and evaluate alteration rinds and coatings on the analyzed rocks. Desert varnish, thin iron and carbon coatings were found on natural side of some rocks, but not others. The elemental composition results by the APXS contributed synergistically with the other FIDO instruments to derive the mineralogical and geological characterization of the sites by imposing limits on the amounts and the variety of specific minerals. Most of the analyzed samples from both FIDO field test sites were very high in silica and alumina. In a few cases, the analyses were compatible with pure quartz. The alpha mode of the APXS is especially valuable for detecting even small amounts of carbonates. In many instances, it was possible to show that the carbon was only on the surface of some rocks. Examples of the APXS results from both blind field tests will be presented and discussed at the meeting The APXS results will be compared to the Pathfinder APXS rock analyses and conclusions will be made about rinds

  5. A Guide to Field Trip Sites in Coastal North Carolina. Project CAPE Teaching Module SC3a.

    ERIC Educational Resources Information Center

    Carroll, Walter B.; Carroll, Carolyn H.

    This guide provides information on preparing students in grades 4-10 for field trips and describes possible field trip sites in the northeastern, mid-eastern, and southeastern regions of North Carolina. Selected sites in the northeastern region (from Roanoke Island to Ocracoke) include the Dare Coastline and Cape Hatteras National Seashore.…

  6. Secondary organic aerosol characterization at field sites across the United States during the spring-summer period

    EPA Science Inventory

    Sources of secondary organic carbon at 15 field sites across the United States (U.S.) during the years 2003-2010 have been examined. Filter samples have been taken for 24-h at a site in Research Triangle Park, NC; at SEARCH sites in southeastern U.S. during May and August 2005; ...

  7. Analysis of field size distributions, LACIE test sites 5029, 5033, and 5039, Anhwei Province, People's Republic of China

    NASA Technical Reports Server (NTRS)

    Podwysocki, M. H.

    1976-01-01

    A study was made of the field size distributions for LACIE test sites 5029, 5033, and 5039, People's Republic of China. Field lengths and widths were measured from LANDSAT imagery, and field area was statistically modeled. Field size parameters have log-normal or Poisson frequency distributions. These were normalized to the Gaussian distribution and theoretical population curves were made. When compared to fields in other areas of the same country measured in the previous study, field lengths and widths in the three LACIE test sites were 2 to 3 times smaller and areas were smaller by an order of magnitude.

  8. SUMMARY OF TECHNIQUES AND UNIQUE USES FOR DIRECT PUSH METHODS IN SITE CHARACTERIZATION ON CONTAMINATED FIELD SITES

    EPA Science Inventory

    Site characterization of subsurface contaminant transport is often hampered by a lack of knowledge of site heterogeneity and temporal variations in hydrogeochemistry. Two case studies are reviewed to illustrate the utility of macro-scale mapping information along with spatially-...

  9. Comparison of Methods to Obtain Force-Field Parameters for Metal Sites.

    PubMed

    Hu, LiHong; Ryde, Ulf

    2011-08-01

    We have critically examined and compared various ways to obtain standard harmonic molecular mechanics (MM) force-field parameters for metal sites in proteins, using the 12 most common Zn(2+) sites as test cases. We show that the parametrization of metal sites is hard to treat with automatic methods. The choice of method is a compromise between speed and accuracy and therefore depends on the intended use of the parameters. If the metal site is not of central interest in the investigation, for example, a structural metal far from the active site, a simple and fast parametrization is normally enough, using either a nonbonded model with restraints or a bonded parametrization based on the method of Seminario. On the other hand, if the metal site is of central interest in the investigation, a more accurate method is needed to give quantitative results, for example, the method by Norrby and Liljefors. The former methods are semiautomatic and can be performed in seconds, once a quantum mechanical (QM) geometry optimization and frequency calculation has been performed, whereas the latter method typically takes several days and requires significant human intervention. All approaches require a careful selection of the atom types used. For a nonbonded model, standard atom types can be used, whereas for a bonded model, it is normally wise to use special atom types for each metal ligand. For accurate results, new atom types for all atoms in the metal site can be used. Atomic charges should also be considered. Typically, QM restrained electrostatic potential charges are accurate and easy to obtain once the QM calculation is performed, and they allow for charge transfer within the complex. For negatively charged complexes, it should be checked that hydrogen atoms of the ligands get proper charges. Finally, water ligands pose severe problems for bonded models in force fields that ignore nonbonded interactions for atoms separated by two bonds. Complexes with a single water ligand

  10. Remote Robotic Geology: Learning from the MER-FIDO Field Test Site

    NASA Astrophysics Data System (ADS)

    Anderson, R. C.; Dohm, J. M.; Haldemann, A. F.; Bass, D. S.; Huntsberger, T. L.

    2002-12-01

    Understanding the geology of a region from a robotic platform can be a challenging and difficult task. In order to prepare the team of investigators and engineers for the upcoming 2003 Mars Exploration Rover (MER) Mission, a "blind" rover field test was performed August 10 - 19, 2002, using the Field Integrated Design and Operations (FIDO) Rover. The field site, which is located near Gray Mountain Arizona (approximately 40 miles north of Flagstaff), was chosen because it: (1) maximizes science return and permits rover trafficability, (2) is easily accessed via a well-maintained mining road, (3) occurs north of Flagstaff, Arizona, where seasonal temperatures are adequate for rover operations and climate records show minimal rainfall, (4) lacks vegetation (a very difficult variable for Earth), and (5) contains diverse geological terrains similar to what might be encountered on Mars, including claystones, siltsones, mudstones, and sandstones of the Shinarump Member of the Chinle Formation. that crop out among fluvially carved drainages, fluvial and eolian deposits that partly blanket the drainage floors, and cobbles and boulders of diverse petrology and geochemistry (e.g., basalt, chert, sandstone, limestone, metamorphic). The goal of the FIDO test was to teach the MER Science Team the techniques involved in conducting a geologic investigation with a remote rover. Inherent disadvantages associated with remote robotic exploration include a limited time-associated visibility to the site. This disadvantage is somewhat offset by the availability of instruments on the rover that might ordinarily be available to a geologist only in a laboratory setting. This talk will further explore the coupling of a remote robotic platform with what is known about the field site to provide insight into future robotic exploration of planetary locales.

  11. Post Audit of a Field Scale Reactive Transport Model of Uranium at a Former Mill Site

    NASA Astrophysics Data System (ADS)

    Curtis, G. P.

    2015-12-01

    Reactive transport of hexavalent uranium (U(VI)) in a shallow alluvial aquifer at a former uranium mill tailings site near Naturita CO has been monitored for nearly 30 years by the US Department of Energy and the US Geological Survey. Groundwater at the site has high concentrations of chloride, alkalinity and U(VI) as a owing to ore processing at the site from 1941 to 1974. We previously calibrated a multicomponent reactive transport model to data collected at the site from 1986 to 2001. A two dimensional nonreactive transport model used a uniform hydraulic conductivity which was estimated from observed chloride concentrations and tritium helium age dates. A reactive transport model for the 2km long site was developed by including an equilibrium U(VI) surface complexation model calibrated to laboratory data and calcite equilibrium. The calibrated model reproduced both nonreactive tracers as well as the observed U(VI), pH and alkalinity. Forward simulations for the period 2002-2015 conducted with the calibrated model predict significantly faster natural attenuation of U(VI) concentrations than has been observed by the persistent high U(VI) concentrations at the site. Alternative modeling approaches are being evaluating evaluated using recent data to determine if the persistence can be explained by multirate mass transfer models developed from experimental observations at the column scale(~0.2m), the laboratory tank scale (~2m), the field tracer test scale (~1-4m) or geophysical observation scale (~1-5m). Results of this comparison should provide insight into the persistence of U(VI) plumes and improved management options.

  12. Evaluating three trace metal contaminated sites: a field and laboratory investigation.

    PubMed

    Murray, P; Ge, Y; Hendershot, W H

    2000-01-01

    Selecting guidelines to evaluate elevated metals in urban brownfields is hindered by the lack of information for these sites on ecosystem structure and function. A study was performed to compare three trace metal-contaminated sites in the metropolitan Montreal area. The goal was to obtain an idea of the organisms that may be present on urban brownfields and to measure if elevated metals alter the presence and activity of the indigenous biota. Field and laboratory studies were conducted using simple methodologies to determine the extent to which microbial activity affected by trace metal content, to assess diversity of plant and soil invertebrate communities and to measure phytoaccumulation of trace metals. It was found that microbial activity, as measured by substrate-induced respiration (SIR) and nitrification, was not affected by the levels of soil Cd, Cu, Ni, Pb and Zn recorded on the sites. Seven of the 12 invertebrate groups collected were sampled on soils with similar Cd, Cu, Ni, Pb and Zn concentrations. Diversity of plant species increased as a function of the length of time the sites had been inactive. Levels of metals in plant tissue were influenced by soil characteristics and not by total soil Cd, Cu, Ni, Pb and Zn.

  13. Problems getting from the laboratory to the field: Reclamation of an AML site

    SciTech Connect

    Dick, W.A.; Stehouwer, R.C.; Bigham, J.M.; Beeghly, J.H.

    1994-12-31

    Acid and toxic abandoned mineland sites provide an opportunity whereby flue gas desulfurization (FGD) by-product can be beneficially used as a reclamation amendment material. Studies are needed to compare the effectiveness of FGD by-product, as compared with resoil, for reclamation purposes. Initial studies provided information about the chemical and physical properties of the FGD by-product and how to transport and blend the FGD by-product with yard waste compost. Greenhouse studies indicated that rates of 125 dry tons/acre of FGD and 50 dry tons/acre of yard waste compost would provide optimum results for reclamation of acid and toxic spoil contained at the Fleming abandoned mineland (AML) site. Their results showed that heavy metal loading rates were much lower using the FGD/compost mixture than using resoil material. Dioxin in the mixture was also less than the 5 ppt level considered as normal background. The technical problems of using FGD by-product for reclamation of an AML site were solved. However, considerable efforts to educate the public about the merits of reclaiming the Fleming AML site using this FGD/compost mixture were required before initiating field reclamation activities. Education efforts must continue if FGD by-products are to achieve general acceptance as a reclamation alternative to resoil in cases where resoil is of scarce supply.

  14. Combined remediation technologies: results from field trials at chlorinated solvent impacted sites

    NASA Astrophysics Data System (ADS)

    O'Carroll, D. M.; Chowdhury, A. I.; Lomheim, L.; Boparai, H. K.; Weber, K.; Austrins, L. M.; Edwards, E.; Sleep, B.; de Boer, C. V.; Garcia, A. N.

    2015-12-01

    Non-aqueous phase liquids (NAPLs) are one class of waste liquids often generated from waste mixtures in industrial processes containing surfactants, chlorinated hydrocarbons and other compounds. Chlorinated solvents, a particularly persistent NAPL contaminant, frequently contaminate water sources for decades and are one of the more common contaminants at brownfield and industrialized sites. Although considerable advances in our understanding of the phenomena governing NAPL remediation have been made, and a number of innovative remediation technologies have been developed, existing technologies are rarely able to achieve clean up goals in contaminated aquifers at the completion of remedial activities. The development and pilot scale testing of new and innovative remediation technologies is, therefore, crucial to achieve clean up goals at contaminated sites. Our research group is currently investigating a number of innovative remediation technologies, either individually or as combined remedies. This includes the applicability of nanometals and ISCO (e.g., persulfate) for contaminated site remediation. These technologies can be combined with technologies to enhance amendment delivery (e.g., electrokinetics) or create conditions favorable for enhanced biotic contaminant degradation. This presentation will discuss outcomes from a number of field trials conducted at chlorinated solvent impacted sites by our group with a particular focus on combined remediation technologies.

  15. Criteria for Identifying and Evaluating Candidate Sites for Open-Field Trials of Genetically Engineered Mosquitoes

    PubMed Central

    Brown, David M.; Alphey, Luke S.; McKemey, Andrew; Beech, Camilla

    2014-01-01

    Abstract Recent laboratory successes in the development of genetically engineered mosquitoes for controlling pathogen transmission have fostered the need for standardized procedures for advancing the technical achievements to practical tools. It is incumbent in many cases for the same scientists doing the in-laboratory discovery research to also take on the initial challenges of developing the pathway that will move the technologies to the field. One of these challenges is having a set of criteria for selecting collaborators and sites for efficacy and safety field trials that combine rigorous science with good ethical and legal practices. Specific site-selection criteria were developed in four categories—Scientific, Regulatory, Community Engagement, and Resources—in anticipation of open-field releases of a transgenic mosquito strain designed to suppress populations of the dengue vector mosquito, Aedes aegypti. The criteria are derived from previous published material, discussions, and personal experiences with the expectation of providing guidance to laboratory scientists for addressing the conceptual and operational considerations for identifying partner researchers and countries with whom to collaborate. These criteria are not intended to be prescriptive nor can they be applied to every circumstance where genetic approaches are proposed for deployment. However, we encourage those involved in the discovery phase of research to consider each criterion during project planning activities, and where appropriate, incorporate them into a “go/no-go” decision-making process for further development and testing of the technologies. PMID:24689963

  16. Mapping soil attributes for site-specific management of a Montana field

    NASA Astrophysics Data System (ADS)

    Wilson, John P.; Spangrud, Damian J.; Landon, Melissa A.; Jacobsen, Jeffrey S.; Nielson, Gerald A.

    1995-01-01

    Conventional soil maps represent the distribution of soil attributes across landscapes but with less precision than is needed to obtain the full economic and environmental benefits of site- specific crop management. This study quantifies the spatial variability of three agronomically significant soil attributes: (1) thickness of mollic epipedon, (2) organic matter content (OM), and (3) pH as related to soil survey map units, spectral data, and terrain attributes for a 20 ha field in Montana. Analysis of Order 1 (1:7920-scale) Soil Survey map units indicates substantial variation in all three soil attributes. There was some evidence that similar attribute values were clustered in the field (0.40 - 0.46 Moran's Coefficients). Two spectral band ratios explained 64% of the variation in OM across the field. GPS/GIS-derived wetness index, sediment transport index, elevation, and slope gradient explained 48% of OM variation. Wetness index, slope gradient, and plan curvature combined to explain 48% of the variation in mollic epipedon thickness. Elevation and wetness index explained just 13% of pH variation. Two spectral band ratios, specific catchment area, and wetness index combined to explain 70% of the variation in OM at 66 sampling sites. Four contour map representations of OM illustrate the sensitivity of the final maps to variations in input data and interpolation method.

  17. Field-based supercritical fluid extraction of hydrocarbons at industrially contaminated sites.

    PubMed

    Rigou, Peggy; Setford, Steven John; Saini, Selwayan

    2002-04-19

    Examination of organic pollutants in groundwaters should also consider the source of the pollution, which is often a solid matrix such as soil, landfill waste, or sediment. This premise should be viewed alongside the growing trend towards field-based characterisation of contaminated sites for reasons of speed and cost. Field-based methods for the extraction of organic compounds from solid samples are generally cumbersome, time consuming, or inefficient. This paper describes the development of a field-based supercritical fluid extraction (SFE) system for the recovery of organic contaminants (benzene, toluene, ethylbenzene, and xylene and polynuclear aromatic hydrocarbons) from soils. A simple, compact, and robust SFE system has been constructed and was found to offer the same extraction efficiency as a well-established laboratory SFE system. Extraction optimisation was statistically evaluated using a factorial analysis procedure. Under optimised conditions, the device yielded recovery efficiencies of >70% with RSD values of 4% against the standard EPA Soxhlet method, compared with a mean recovery efficiency of 48% for a commercially available field-extraction kit. The device will next be evaluated with real samples prior to field deployment.

  18. Metal availability in a highly contaminated, dredged-sediment disposal site: field measurements and geochemical modeling.

    PubMed

    Lions, Julie; Guérin, Valérie; Bataillard, Philippe; van der Lee, Jan; Laboudigue, Agnès

    2010-09-01

    Two complementary approaches were used to characterize arsenic and metal mobilizations from a dredged-sediment disposal site: a detailed field study combined with hydrogeochemical modeling. Contaminants in sediments were found to be mainly present as sulfides subject to oxidation. Secondary phases (carbonates, sulfates, (hydr)oxides) were also observed. Oxidative processes occurred at different rates depending on physicochemical conditions and contaminant contents in the sediment. Two distinct areas were identified on the site, each corresponding to a specific contaminant mobility behavior. In a reducing area, Fe and As were highly soluble and illustrated anoxic behavior. In well-oxygenated material, groundwater was highly contaminated in Zn, Cd and Pb. A third zone in which sediments and groundwater were less contaminated was also characterized. This study enabled us to prioritize remediation work, which should aim to limit infiltration and long-term environmental impact.

  19. Quantifying diffuse and discrete venting at the Tour Eiffel vent site, Lucky Strike hydrothermal field

    NASA Astrophysics Data System (ADS)

    Mittelstaedt, Eric; EscartíN, Javier; Gracias, Nuno; Olive, Jean-Arthur; Barreyre, Thibaut; Davaille, Anne; Cannat, Mathilde; Garcia, Rafael

    2012-04-01

    The relative heat carried by diffuse versus discrete venting of hydrothermal fluids at mid-ocean ridges is poorly constrained and likely varies among vent sites. Estimates of the proportion of heat carried by diffuse flow range from 0% to 100% of the total axial heat flux. Here, we present an approach that integrates imagery, video, and temperature measurements to accurately estimate this partitioning at a single vent site, Tour Eiffel in the Lucky Strike hydrothermal field along the Mid-Atlantic Ridge. Fluid temperatures, photographic mosaics of the vent site, and video sequences of fluid flow were acquired during the Bathyluck'09 cruise (Fall, 2009) and the Momarsat'10 cruise (Summer, 2010) to the Lucky Strike hydrothermal field by the ROV Victor6000 aboard the French research vessel the "Pourquoi Pas"? (IFREMER, France). We use two optical methods to calculate the velocities of imaged hydrothermal fluids: (1) for diffuse venting, Diffuse Flow Velocimetry tracks the displacement of refractive index anomalies through time, and (2) for discrete jets, Particle Image Velocimetry tracks eddies by cross-correlation of pixel intensities between subsequent images. To circumvent video blurring associated with rapid velocities at vent orifices, exit velocities at discrete vents are calculated from the best fit of the observed velocity field to a model of a steady state turbulent plume where we vary the model vent radius and fluid exit velocity. Our results yield vertical velocities of diffuse effluent between 0.9 cm s-1 and 11.1 cm s-1 for fluid temperatures between 3°C and 33.5°C above that of ambient seawater, and exit velocities of discrete jets between 22 cm s-1 and 119 cm s-1 for fluid temperatures between 200°C and 301°C above ambient seawater. Using the calculated fluid velocities, temperature measurements, and photo mosaics of the actively venting areas, we calculate a heat flux due to diffuse venting from thin fractures of 3.15 ± 2.22 MW, discrete venting of

  20. Multi-site study of diffusion metric variability: effects of site, vendor, field strength, and echo time on regions-of-interest and histogram-bin analyses

    NASA Astrophysics Data System (ADS)

    Helmer, K. G.; Chou, M.-C.; Preciado, R. I.; Gimi, B.; Rollins, N. K.; Song, A.; Turner, J.; Mori, S.

    2016-03-01

    It is now common for magnetic-resonance-imaging (MRI) based multi-site trials to include diffusion-weighted imaging (DWI) as part of the protocol. It is also common for these sites to possess MR scanners of different manufacturers, different software and hardware, and different software licenses. These differences mean that scanners may not be able to acquire data with the same number of gradient amplitude values and number of available gradient directions. Variability can also occur in achievable b-values and minimum echo times. The challenge of a multi-site study then, is to create a common protocol by understanding and then minimizing the effects of scanner variability and identifying reliable and accurate diffusion metrics. This study describes the effect of site, scanner vendor, field strength, and TE on two diffusion metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA) using two common analyses (region-of-interest and mean-bin value of whole brain histograms). The goal of the study was to identify sources of variability in diffusion-sensitized imaging and their influence on commonly reported metrics. The results demonstrate that the site, vendor, field strength, and echo time all contribute to variability in FA and MD, though to different extent. We conclude that characterization of the variability of DTI metrics due to site, vendor, field strength, and echo time is a worthwhile step in the construction of multi-center trials.

  1. Electric field gradients at indium sites in spinels measured by perturbed angular correlations

    NASA Astrophysics Data System (ADS)

    Pasquevich, A. F.

    2005-07-01

    The Electric Field Gradient (EFG) at 111Cd isotope (produced by the Electron Capture (EC) decay of 111In) has been measured using Perturbed Angular Correlations (PAC) technique in many spinels. In the present work, data arising from such experiments were collected. The experimental EFG values, obtained at room temperature, at the B site of normal spinels are compared with those calculated considering the monopole moment of the ions and the dipole polarization of the anions. This comparison allows the determination of the u-parameter, which gives the anion position in the lattice.

  2. Integration of geological, geochemical, and geophysical spatial data of the Cement oil field, Oklahoma, test site

    USGS Publications Warehouse

    Termain, Patricia A.; Donovan, Terrence J.; Chavez, Pat S.

    1980-01-01

    Measurement pertaining to geology, geochemistry, and geophysics of the Cement oil field, Oklahoma, test site were collected employing both airborne sensors and ground-based data collection. The measurements include: (1) airborne gamma-ray spectrometry (supplying bismuth 214, thalium 208, and potassium 40 gamma-ray intensities); (2) aeromagnetic survey data; (3) multi-frequency airborne resistivity survey data (supplying apparent electrical resistivity of near surface materials); (4) gravity data; (5) geological and topographic maps; and (6) image data from Landsat MSS and U-2 photography.

  3. Savannah River Site management response plan for chemical safety vulnerability field assessment. Revision 1

    SciTech Connect

    Kahal, E.J.; Murphy, S.L.; Salaymeh, S.R.

    1994-09-01

    As part of the U.S. Department of Energy`s (DOE) initiative to identify potential chemical safety vulnerabilities in the DOE complex, the Chemical Safety Vulnerability Core Working Group issued a field verification assessment report. While the report concluded that Savannah River Site (SRS) is moving in a positive direction, the report also identified five chemical safety vulnerabilities with broad programmatic impact that are not easily nor quickly remedied. The May 1994 SRS Management Response Plan addressed the five SRS vulnerabilities identified in the field assessment report. The SRS response plan listed observations supporting the vulnerabilities and any actions taken or planned toward resolution. Many of the observations were resolved by simple explanations, such as the existence of implementation plans for Safety Analysis Report updates. Recognizing that correcting individual observations does not suffice in remedying the vulnerabilities, a task team was assembled to address the broader programmatic issues and to recommend corrective actions.

  4. Directional changes of the geomagnetic field in West Africa: Insights from the metallurgical site of Korsimoro

    NASA Astrophysics Data System (ADS)

    Donadini, Fabio; Serneels, Vincent; Kapper, Lisa; El Kateb, Akram

    2015-11-01

    This work shows the first archeomagnetic directions from Western Africa measured on 32 iron smelting kilns dated between 650 and 1800 AD. The archeological excavation of the vast metallurgical site of Korsimoro established the existence of four distinct iron-smelting techniques. The time-frame of each technique could be clearly determined with radiocarbon dating. Many of the kilns investigated in this study could also be dated individually with residual charcoals found in their inside. The results indicate that the inclination of the field changed gradually from shallow normal to shallow reversed during 800 to 1300 AD, and then went back to shallow normal around 1600-1700 AD. The declination was instead stable around 10°E between 800 and 1400 AD, thereafter it started changing towards North. This trend correlates well with available secular variation curves from the Balkan and from Spain, and indicates that the field variation in West Africa was similar to the one in Europe.

  5. Field tests of 2- and 40-tube condensers at the East Mesa Geothermal Test Site

    SciTech Connect

    Murphy, R.W.; Domingo, N.

    1982-05-01

    Two water-cooled isobutane condensers, one with 2 tubes and one with 40 tubes, were subjected to field tests at the East Mesa Geothermal Test Site to assess relative heat transfer performance in both surface evaporator and direct-contact evaporator modes. The five groups of tests established that field performance was below earlier laboratory-determined levels and that direct-contact evaporator mode performance was poorer than that for the surface evaporator mode. In all test situations, fluted condenser tubes performed better than smooth condenser tubes. Cooling water quality had no significant effect on performance, but brine preflash in the direct-contact mode did promote some relative performance improvement. Important implications of these results for binary geothermal power plants are that (1) working-fluid-side impurities can significantly degrade heat transfer performance of the power plant condensers and (2) provisions for minimizing such impurities may be required.

  6. Leaching of glyphosate and amino-methylphosphonic acid from Danish agricultural field sites.

    PubMed

    Kjaer, Jeanne; Olsen, Preben; Ullum, Marlene; Grant, Ruth

    2005-01-01

    Pesticide leaching is an important process with respect to contamination risk to the aquatic environment. The risk of leaching was thus evaluated for glyphosate (N-phosphonomethyl-glycine) and its degradation product AMPA (amino-methylphosphonic acid) under field conditions at one sandy and two loamy sites. Over a 2-yr period, tile-drainage water, ground water, and soil water were sampled and analyzed for pesticides. At a sandy site, the strong soil sorption capacity and lack of macropores seemed to prevent leaching of both glyphosate and AMPA. At one loamy site, which received low precipitation with little intensity, the residence time within the root zone seemed sufficient to prevent leaching of glyphosate, probably due to degradation and sorption. Minor leaching of AMPA was observed at this site, although the concentration was generally low, being on the order of 0.05 microg L(-1) or less. At another loamy site, however, glyphosate and AMPA leached from the root zone into the tile drains (1 m below ground surface [BGS]) in average concentrations exceeding 0.1 microg L(-1), which is the EU threshold value for drinking water. The leaching of glyphosate was mainly governed by pronounced macropore flow occurring within the first months after application. AMPA was frequently detected more than 1.5 yr after application, thus indicating a minor release and limited degradation capacity within the soil. Leaching has so far been confined to the depth of the tile drains, and the pesticides have rarely been detected in monitoring screens located at lower depths. This study suggests that as both glyphosate and AMPA can leach through structured soils, they thereby pose a potential risk to the aquatic environment.

  7. Hybrid simulations: combining atomistic and coarse-grained force fields using virtual sites.

    PubMed

    Rzepiela, Andrzej J; Louhivuori, Martti; Peter, Christine; Marrink, Siewert J

    2011-06-14

    Hybrid simulations, in which part of the system is represented at atomic resolution and the remaining part at a reduced, coarse-grained, level offer a powerful way to combine the accuracy associated with the atomistic force fields to the sampling speed obtained with coarse-grained (CG) potentials. In this work we introduce a straightforward scheme to perform hybrid simulations, making use of virtual sites to couple the two levels of resolution. With the help of these virtual sites interactions between molecules at different levels of resolution, i.e. between CG and atomistic molecules, are treated the same way as the pure CG-CG interactions. To test our method, we combine the Gromos atomistic force field with a number of coarse-grained potentials, obtained through several approaches that are designed to obtain CG potentials based on an existing atomistic model, namely iterative Boltzmann inversion, force matching, and a potential of mean force subtraction procedure (SB). We also explore the use of the MARTINI force field for the CG potential. A simple system, consisting of atomistic butane molecules dissolved in CG butane, is used to study the performance of our hybrid scheme. Based on the potentials of mean force for atomistic butane in CG solvent, and the properties of 1:1 mixtures of atomistic and CG butane which should exhibit ideal mixing behavior, we conclude that the MARTINI and SB potentials are particularly suited to be combined with the atomistic force field. The MARTINI potential is subsequently used to perform hybrid simulations of atomistic dialanine peptides in both CG butane and water. Compared to a fully atomistic description of the system, the hybrid description gives similar results provided that the dielectric screening of water is accounted for. Within the field of biomolecules, our method appears ideally suited to study e.g. protein-ligand binding, where the active site and ligand are modeled in atomistic detail and the rest of the protein

  8. SUMMARY OF TECNIQUES AND UNIQUE USES FOR DIRECT PUSH METHODS IN SITE CHARACTERIZATION ON CONTAMINATED FIELD SITES

    EPA Science Inventory

    At many of the sites where we have been asked to assist in site characterization, we have discovered severe discrepancies that new technologies may be able to prevent. This presentation is designed to illustrate these new technologies or unique uses of existing technology and the...

  9. Field studies of the potential for wind transport of plutonium- contaminated soils at sites in Areas 6 and 11, Nevada Test Site

    SciTech Connect

    Lancaster, N.; Bamford, R.; Metzger, S.

    1995-07-01

    This report describes and documents a series of field experiments carried out in Areas 6 and 11 of the Nevada Test Site in June and July 1994 to determine parameters of boundary layer winds, surface characteristics, and vegetation cover that can be used to predict dust emissions from the affected sites. Aerodynamic roughness of natural sites is determined largely by the lateral cover of the larger and more permanent roughness elements (shrubs). These provide a complete protection of the surface from wind erosion. Studies using a field-portable wind tunnel demonstrated that natural surfaces in the investigated areas of the Nevada Test Site are stable except at very high wind speeds (probably higher than normally occur, except perhaps in dust devils). However, disturbance of silty-clay surfaces by excavation devices and vehicles reduces the entrainment threshold by approximately 50% and makes these areas potentially very susceptible to wind erosion and transport of sediments.

  10. Remaining Sites Verification Package for the 331 Life Sciences Laboratory Drain Field Septic System, Waste Site Reclassification Form 2008-020

    SciTech Connect

    J. M. Capron

    2008-10-16

    The 331 Life Sciences Laboratory Drain Field (LSLDF) septic system waste site consists of a diversion chamber, two septic tanks, a distribution box, and a drain field. This septic system was designed to receive sanitary waste water, from animal studies conducted in the 331-A and 331-B Buildings, for discharge into the soil column. However, field observations and testing suggest the 331 LSLDF septic system did not receive any discharges. In accordance with this evaluation, the confirmatory sampling results support a reclassification of the 331 LSLDF waste site to No Action. This site does not have a deep zone or other condition that would warrant an institutional control in accordance with the 300-FF-2 ROD under the industrial land use scenario.

  11. Simulating a MER Landing Site Remote Sensing Data Set for the 2002 FIDO Field Test

    NASA Astrophysics Data System (ADS)

    Andres, P. M.; Anderson, R. C.; Bryant, N. A.; Capraro, K. S.; de Jong, E. M.; Haldemann, A. F.; Kiefer, D. E.; Levoe, S. R.; Logan, T. L.; Stein, T.

    2002-12-01

    To support the Field Integrated Design and Operations (FIDO) rover field test for Mars Exploration Rover (MER) science team training, we assembled a portfolio of modified terrestrial remote-sensing data to imitate the datasets available for MER landing sites. The MER landing sites data we synthesized were:\\(i) Viking MDIM base images at around 200 m/pixel, \\(ii) interpolated 1/64th degree Mars Global Surveyor (MGS) Mars Orbital Laser Altimeter (MOLA) topography, \\(iii) MOLA topographic profiles, \\(iv) some number of MGS Mars Orbiter Camera (MOC) high resolution strips, \\(v) Mars Odyssey Thermal Emission Imaging Spectrometer (THEMIS) visible (VIS) and short-wave infrared (SWIR) reflectance images, and \\(vi) THEMIS thermal IR (TIR) emissivity images. \\Terrestrial datasets selected and modified were (respectively):\\(i) Landsat TM composite images 90 m/pixel degraded to 180 m/pixel, \\(ii) USGS 90 m/pixel DEM degraded to 450 m/pixel, \\(iii) the same USGS 90 m/pixel DEM was individually sampled to generate 100 m shot size MOLA profiles, \\(iv) USGS Digital Orthoquad 1 m/pixel aerial photographs, mosaiced, cropped and re-sampled to 1.5, 3, and 7 m/pixel, \\(v) ASTER VIS and SWIR Level 2 reflectance, and \\(vi) ASTER TIR emissivity images.\\The MER Athena science team was able to successfully assess and evaluate the scientific potential of their test "landing ellipse" using these data, suggesting that the team will be capable of similar interpretive extrapolation on Mars.

  12. Field application of innovative grouting agents for in situ stabilization of buried waste sites

    SciTech Connect

    Loomis, G.G.; Farnsworth, R.K.

    1997-12-31

    This paper presents field applications for two innovative grouting agents that were used to in situ stabilize buried waste sites, via jet grouting. The two grouting agents include paraffin and a proprietary iron oxide based cement grout called TECT. These materials were tested in specially designed cold test pits that simulate buried transuranic waste at the Idaho National Engineering Laboratory (INEL). The field demonstrations were performed at the INEL in an area referred to as the Cold Test Pit, which is adjacent to the INEL Radioactive Waste Management Complex (RWMC). At the RWMC, 56,000 m{sup 3} of transuranic (TRU) waste is co-mingled with over 170,000 m{sup 3} of soil in shallow land burial. Improving the confinement of this waste is one of the options for final disposition of this waste. Using jet-grouting technology to inject these materials into the pore spaces of buried waste sites results in the creation of buried monolithic waste forms that simultaneously protect the waste from subsidence, while eliminating the migratory potential of hazardous and radioactive contaminants in the waste.

  13. Highly parameterized inversion of groundwater reactive transport for a complex field site.

    PubMed

    Carniato, Luca; Schoups, Gerrit; van de Giesen, Nick; Seuntjens, Piet; Bastiaens, Leen; Sapion, Hans

    2015-02-01

    In this study a numerical groundwater reactive transport model of a shallow groundwater aquifer contaminated with volatile organic compounds is developed. In addition to advective-dispersive transport, the model includes contaminant release from source areas, natural attenuation, abiotic degradation by a permeable reactive barrier at the site, and dilution by infiltrating rain. Aquifer heterogeneity is parameterized using pilot points for hydraulic conductivity, specific yield and groundwater recharge. A methodology is developed and applied to estimate the large number of parameters from the limited data at the field site (groundwater levels, groundwater concentrations of multiple chemical species, point-scale measurements of soil hydraulic conductivity, and lab-scale derived information on chemical and biochemical reactions). The proposed methodology relies on pilot point parameterization of hydraulic parameters and groundwater recharge, a regularization procedure to reconcile the large number of spatially distributed model parameters with the limited field data, a step-wise approach for integrating the different data sets into the model, and high performance computing. The methodology was proven to be effective in reproducing multiple contaminant plumes and in reducing the prior parameter uncertainty of hydraulic conductivity and groundwater recharge. Our results further indicate that contaminant transport predictions are strongly affected by the choice of the groundwater recharge model and flow parameters should be identified using both head and concentration measurements.

  14. Highly parameterized inversion of groundwater reactive transport for a complex field site

    NASA Astrophysics Data System (ADS)

    Carniato, Luca; Schoups, Gerrit; van de Giesen, Nick; Seuntjens, Piet; Bastiaens, Leen; Sapion, Hans

    2015-02-01

    In this study a numerical groundwater reactive transport model of a shallow groundwater aquifer contaminated with volatile organic compounds is developed. In addition to advective-dispersive transport, the model includes contaminant release from source areas, natural attenuation, abiotic degradation by a permeable reactive barrier at the site, and dilution by infiltrating rain. Aquifer heterogeneity is parameterized using pilot points for hydraulic conductivity, specific yield and groundwater recharge. A methodology is developed and applied to estimate the large number of parameters from the limited data at the field site (groundwater levels, groundwater concentrations of multiple chemical species, point-scale measurements of soil hydraulic conductivity, and lab-scale derived information on chemical and biochemical reactions). The proposed methodology relies on pilot point parameterization of hydraulic parameters and groundwater recharge, a regularization procedure to reconcile the large number of spatially distributed model parameters with the limited field data, a step-wise approach for integrating the different data sets into the model, and high performance computing. The methodology was proven to be effective in reproducing multiple contaminant plumes and in reducing the prior parameter uncertainty of hydraulic conductivity and groundwater recharge. Our results further indicate that contaminant transport predictions are strongly affected by the choice of the groundwater recharge model and flow parameters should be identified using both head and concentration measurements.

  15. Investigation of water productivity for maize with focus on the difference in global radiation between a greenhouse and a field site

    NASA Astrophysics Data System (ADS)

    Kloss, Sebastian; Schütze, Niels

    2015-04-01

    time. The study concludes with the quantification of the crops' different exposure to global radiation at the three sites and compares achieved crop yields and water consumption. Results give a first indication about the actual difference in global radiation exposure and how to improve simulation models when conduction small pot irrigation experiments and transfer of their results to the field.

  16. Risk-Based Cleanup Actions for Closure of a Brown field Site

    SciTech Connect

    Rice, H.W.; Feild, J.F.; Farr Jr, L.C.

    2007-07-01

    Operating as a rail yard from approximately 1908 to 1987, Station Place is a 7.1-acre (4,046 square meter) property located in the downtown Portland, Oregon, River District Urban Renewal Area. The site soils were impacted with metals and polynuclear aromatic hydrocarbon compounds (PAHs). Benzene and select PAHs were detected in the shallow groundwater. Residual non-aqueous phase liquid (NAPL) was detected within the shallow saturated zone between 15 and 40 feet (4.5 to 12 meters) below grade and in the Troutdale Formation (used for municipal water supply at up-gradient location) at depths of up to 80 feet (24 meters) below grade. Site closure was obtained and redevelopment was completed at the site, by the Portland Development Commission and REACH Community Development, Inc., following the preparation of a baseline deterministic human health risk assessment, and beneficial land and water use determination to assess whether exposure to groundwater and soil posed a threat to human health or the environment. The property now provides affordable housing for the elderly and a city-owned parking garage. The housing provides substantial community benefit, allowing elderly people to live in a vibrant, exciting part of the city. Portland's city-owned parking garages also provide much needed parking space at reasonable rates. Both of these additions have changed an under-used Brown Field into affordable facilities, in a lively urban environment. (authors)

  17. A field trial for an ex-situ bioremediation of a drilling mud-polluted site.

    PubMed

    Rojas-Avelizapa, N G; Roldán-Carrillo, T; Zegarra-Martínez, H; Muñoz-Colunga, A M; Fernández-Linares, L C

    2007-01-01

    The remediation of drilling mud-polluted sites in the Southeast of Mexico is a top priority for Mexican oil industry. The objective of this work was to find a technology to remediate these sites. A field trial was performed by composting in biopiles, where four 1ton soil-biopiles were established, one treatment in triplicate and one unamended biopile. Amended biopiles were added with nutrients to get a C/N/P ratio of 100/3/0.5 plus a bulking agent (straw) at a soil/straw ratio of 97/3. Moisture content was maintained around 30-35%. Results showed that, after 180 d, total petroleum hydrocarbon (TPH) concentrations decreased from 99300+/-23000mgTPHkg(-1) soil to 5500+/-770mgTPHkg(-1) for amended biopiles and to 22900+/-7800mgTPHkg(-1) for unamended biopile. An undisturbed soil control showed no change in TPH concentrations. Gas chromatographic analysis showed residual alkyl dibenzothiophene type compounds. Highest bacterial counts were observed during the first 30 d which correlated with highest TPH removal, whereas fungal count increased at the end of the experimentation period. Results suggested an important role of the straw, nutrient addition and water content in stimulating aerobic microbial activity and thus hydrocarbon removal. This finding opens an opportunity to remediate old polluted sites with recalcitrant and high TPH concentration.

  18. MODIS tools for land validation, field site characterization, data intensive science and classroom education

    NASA Astrophysics Data System (ADS)

    Santhana Vannan, S.; Cook, R. B.; Wilson, B. E.

    2010-12-01

    The MODIS (Moderate Resolution Imaging Spectroradiometer) sensor data are highly useful for field research. The spectral, spatial and temporal characteristics of MODIS products have made them an important data source for analyzing key science questions relating to Earth System processes at regional, continental, and global scales. MODIS data are particularly useful to validate and inter-compare ground measurements at various field sites such as flux tower locations. MODIS data are also useful in land validation, understanding biogeochemical and ecological processes, and providing environmental data to support citizen science efforts. However, MODIS data volume and the complexity in data format makes MODIS data less usable in some cases. To solve this usability issue, the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) has developed a system that prepares and distributes subsets of selected MODIS land products in a scale and format useful for field researchers. Web and Web service tools provide MODIS subsets in ASCII format and in GIS compatible GeoTIFF format. Users can download and visualize MODIS subsets for a set of pre-defined locations, order MODIS subsets for any land location or automate the process of subset extraction using a SOAP based Web service. This paper provides a description of these tools and services with couple of application examples. The MODIS tools and services can be extended to support the large volume of data that would be produced by the various decadal survey missions. The MODIS subsets are provided for more than 1,000 sites across the globe. Most of the eddy covariance flux tower sites are included in the site list. The subsets are offered in tabular ASCII format and in GIS compatible GeoTIFF format. Time series plots and grid visualizations to help characterize field sites are also provided. In addition to offering subsets for fixed sites, the ORNL DAAC also offers the capability to create user

  19. Evaluation of Aqua-Ammonia Chiller Technologies and Field Site Installation

    SciTech Connect

    Zaltash, Abdolreza

    2007-09-01

    The Naval Facilities Engineering Service Center (NFESC) has sponsored Oak Ridge National Laboratory (ORNL) to review, select, and evaluate advanced, gas-fired, 5-ton, aqua-ammonia, chiller technologies. The selection criteria was that units have COP values of 0.67 or better at Air-conditioning and Refrigeration Institute (ARI) 95 F outdoor rating conditions, an active refrigerant flow control, and a variable-speed condenser fan. These features are expected to allow these units to operate at higher ambient temperatures (up to the maximum operating temperature of 110 F) with minimal degradation in performance. ORNL evaluated three potential manufacturers of advanced, gas-fired, 5-ton, aqua-ammonia chillers-Robur, Ambian, and Cooling Technologies. Unfortunately, Robur did not meet the COP requirements and Cooling Technologies could not deliver a unit to be tested at the U.S. Department of Energy (DOE)-ORNL environmental chamber testing facility for thermally activated heat pumps. This eliminated these two technologies from further consideration, leaving only the Ambian chillers for evaluation. Two Ambian chillers were evaluated at the DOE-ORNL test facility. Overall these chillers operated well over a wide range of ambient conditions with minimal degradation in performance due to several control strategies used such as a variable speed condenser fan, a modulating burner, and active refrigerant flow control. These Ambian pre-commercial units were selected for installation and field testing at three federal facilities. NFESC worked with ORNL to assist with the site selection for installation and evaluation of these chillers. Two sites (ORNL and Naval Surface Warfare Center [NSWC] Corona) had a single chiller unit installed; and at one site (Naval Amphibious Base [NAB] Little Creek), two 5-ton chillers linked together were installed to provide 10 tons of cooling. A chiller link controller developed under this project was evaluated in the field test at Little Creek.

  20. Multi-site study of diffusion metric variability: characterizing the effects of site, vendor, field strength, and echo time using the histogram distance

    NASA Astrophysics Data System (ADS)

    Helmer, K. G.; Chou, M.-C.; Preciado, R. I.; Gimi, B.; Rollins, N. K.; Song, A.; Turner, J.; Mori, S.

    2016-03-01

    MRI-based multi-site trials now routinely include some form of diffusion-weighted imaging (DWI) in their protocol. These studies can include data originating from scanners built by different vendors, each with their own set of unique protocol restrictions, including restrictions on the number of available gradient directions, whether an externally generated list of gradient directions can be used, and restrictions on the echo time (TE). One challenge of multi-site studies is to create a common imaging protocol that will result in a reliable and accurate set of diffusion metrics. The present study describes the effect of site, scanner vendor, field strength, and TE on two common metrics: the first moment of the diffusion tensor field (mean diffusivity, MD), and the fractional anisotropy (FA). We have shown in earlier work that ROI metrics and the mean of MD and FA histograms are not sufficiently sensitive for use in site characterization. Here we use the distance between whole brain histograms of FA and MD to investigate within- and between-site effects. We concluded that the variability of DTI metrics due to site, vendor, field strength, and echo time could influence the results in multi-center trials and that histogram distance is sensitive metrics for each of these variables.

  1. Probabilistic study of well capture zones distribution at the Lauswiesen field site.

    PubMed

    Riva, M; Guadagnini, L; Guadagnini, A; Ptak, T; Martac, E

    2006-11-20

    The delineation of well capture zones is of utmost environmental and engineering relevance as pumping wells are commonly used both for drinking water supply needs, where protection zones have to be defined, and for investigation and remediation of contaminated aquifers. We analyze the probabilistic nature of well capture zones within the well field located at the "Lauswiesen" experimental site. The test site is part of an alluvial heterogeneous aquifer located in the Neckar river valley, close to the city of Tübingen in South-West Germany. We explore the effect of different conceptual models of the structure of aquifer heterogeneities on the delineation of three-dimensional probabilistic well catchment and time-related capture zones, in the presence of migration of conservative solutes. The aquifer is modeled as a three-dimensional, doubly stochastic composite medium, where distributions of geo-materials and hydraulic properties are uncertain. We study the relative importance of uncertain facies geometry and uncertain hydraulic conductivity and porosity on predictions of catchment and solute time of travel to the pumping well by focusing on cases in which (1) the facies distribution is random, but the hydraulic properties of each material are fixed, and (2) both facies geometry and material properties vary stochastically. The problem is tackled within a conditional numerical Monte Carlo framework. Results are provided in terms of probabilistic demarcations of the three-dimensional well catchment and time-related capture zones. Our findings suggest that the uncertainty associated with the prediction of the location of the outer boundary of well catchment at the "Lauswiesen" site is significantly affected by the conceptual model adopted to incorporate the heterogeneous nature of the aquifer domain in a predictive framework. Taking into account randomness of both lithofacies distribution and materials hydraulic conductivity allows recognizing the existence of

  2. Probabilistic study of well capture zones distribution at the Lauswiesen field site.

    PubMed

    Riva, M; Guadagnini, L; Guadagnini, A; Ptak, T; Martac, E

    2006-11-20

    The delineation of well capture zones is of utmost environmental and engineering relevance as pumping wells are commonly used both for drinking water supply needs, where protection zones have to be defined, and for investigation and remediation of contaminated aquifers. We analyze the probabilistic nature of well capture zones within the well field located at the "Lauswiesen" experimental site. The test site is part of an alluvial heterogeneous aquifer located in the Neckar river valley, close to the city of Tübingen in South-West Germany. We explore the effect of different conceptual models of the structure of aquifer heterogeneities on the delineation of three-dimensional probabilistic well catchment and time-related capture zones, in the presence of migration of conservative solutes. The aquifer is modeled as a three-dimensional, doubly stochastic composite medium, where distributions of geo-materials and hydraulic properties are uncertain. We study the relative importance of uncertain facies geometry and uncertain hydraulic conductivity and porosity on predictions of catchment and solute time of travel to the pumping well by focusing on cases in which (1) the facies distribution is random, but the hydraulic properties of each material are fixed, and (2) both facies geometry and material properties vary stochastically. The problem is tackled within a conditional numerical Monte Carlo framework. Results are provided in terms of probabilistic demarcations of the three-dimensional well catchment and time-related capture zones. Our findings suggest that the uncertainty associated with the prediction of the location of the outer boundary of well catchment at the "Lauswiesen" site is significantly affected by the conceptual model adopted to incorporate the heterogeneous nature of the aquifer domain in a predictive framework. Taking into account randomness of both lithofacies distribution and materials hydraulic conductivity allows recognizing the existence of

  3. A FIELD EVALUATION OF IN-SITU BIODEGRADATION OF CHLORINATED ETHENES: PART I, METHODOLOGY AND FIELD SITE CHARACTERIZATION

    EPA Science Inventory

    Careful site characterization and implementation of quantitative monitoring methods are prerequisites for a convincing evaluation of enhanced biostimulation for aquifer restoration. This paper describes the characterization of a site at Moffett Naval Air Station, Mountain View, C...

  4. Implementation of a DOD ELAP Conforming Quality System at a FUSRAP Site Field Temporary Radiological Screening Laboratory - 13500

    SciTech Connect

    Winters, M.S.; McElheny, G.; Houston, L.M.; Masset, M.R.; Spector, H.L.

    2013-07-01

    A case study is presented on specific program elements that supported the transition of a temporary field radiological screening lab to an accredited operation capable of meeting client quality objectives for definitive results data. The temporary field lab is located at the Formerly Utilized Sites Remedial Action Program Linde Site in Tonawanda, NY. The site is undergoing remediation under the direction of the United States Army Corps of Engineers - Buffalo District, with Cabrera Services Inc. as the remediation contractor and operator of the on-site lab. Analysis methods employed in the on-site lab include gross counting of alpha and beta particle activity on swipes and air filters and gamma spectroscopy of soils and other solid samples. A discussion of key program elements and lessons learned may help other organizations considering pursuit of accreditation for on-site screening laboratories. (authors)

  5. Facebook as a Library Tool: Perceived vs. Actual Use

    ERIC Educational Resources Information Center

    Jacobson, Terra B.

    2011-01-01

    As Facebook has come to dominate the social networking site arena, more libraries have created their own library pages on Facebook to create library awareness and to function as a marketing tool. This paper examines reported versus actual use of Facebook in libraries to identify discrepancies between intended goals and actual use. The results of a…

  6. Field study of in situ remediation of petroleum hydrocarbon contaminated soil on site using microwave energy.

    PubMed

    Chien, Yi-Chi

    2012-01-15

    Many laboratory-scale studies strongly suggested that remediation of petroleum hydrocarbon contaminated soil by microwave heating is very effective; however, little definitive field data existed to support the laboratory-scale observations. This study aimed to evaluate the performance of a field-scale microwave heating system to remediate petroleum hydrocarbon contaminated soil. A constant microwave power of 2 kW was installed directly in the contaminated area that applied in the decontamination process for 3.5h without water input. The C10-C40 hydrocarbons were destroyed, desorbed or co-evaporated with moisture from soil by microwave heating. The moisture may play an important role in the absorption of microwave and in the distribution of heat. The success of this study paved the way for the second and much larger field test in the remediation of petroleum hydrocarbon contaminated soil by microwave heating in place. Implemented in its full configuration for the first time at a real site, the microwave heating has demonstrated its robustness and cost-effectiveness in cleaning up petroleum hydrocarbon contaminated soil in place. Economically, the concept of the microwave energy supply to the soil would be a network of independent antennas which powered by an individual low power microwave generator. A microwave heating system with low power generators shows very flexible, low cost and imposes no restrictions on the number and arrangement of the antennas.

  7. Investigating temporal field sampling strategies for site-specific calibration of three soil moisture-neutron intensity parameterisation methods

    NASA Astrophysics Data System (ADS)

    Iwema, J.; Rosolem, R.; Baatz, R.; Wagener, T.; Bogena, H. R.

    2015-07-01

    The Cosmic-Ray Neutron Sensor (CRNS) can provide soil moisture information at scales relevant to hydrometeorological modelling applications. Site-specific calibration is needed to translate CRNS neutron intensities into sensor footprint average soil moisture contents. We investigated temporal sampling strategies for calibration of three CRNS parameterisations (modified N0, HMF, and COSMIC) by assessing the effects of the number of sampling days and soil wetness conditions on the performance of the calibration results while investigating actual neutron intensity measurements, for three sites with distinct climate and land use: a semi-arid site, a temperate grassland, and a temperate forest. When calibrated with 1 year of data, both COSMIC and the modified N0 method performed better than HMF. The performance of COSMIC was remarkably good at the semi-arid site in the USA, while the N0mod performed best at the two temperate sites in Germany. The successful performance of COSMIC at all three sites can be attributed to the benefits of explicitly resolving individual soil layers (which is not accounted for in the other two parameterisations). To better calibrate these parameterisations, we recommend in situ soil sampled to be collected on more than a single day. However, little improvement is observed for sampling on more than 6 days. At the semi-arid site, the N0mod method was calibrated better under site-specific average wetness conditions, whereas HMF and COSMIC were calibrated better under drier conditions. Average soil wetness condition gave better calibration results at the two humid sites. The calibration results for the HMF method were better when calibrated with combinations of days with similar soil wetness conditions, opposed to N0mod and COSMIC, which profited from using days with distinct wetness conditions. Errors in actual neutron intensities were translated to average errors specifically to each site. At the semi-arid site, these errors were below the

  8. Corrective measures technology for shallow land burial at arid sites: field studies of biointrusion barriers and erosion control

    SciTech Connect

    Nyhan, J.W.; Hakonson, T.E.; Lopez, E.A.

    1986-03-01

    The field research program involving corrective measures technologies for arid shallow land burial (SLB) sites is described. Results of field testing of a biointrusion barrier installed at a close-out waste disposal site (Area B) at Los Alamos are presented. Soil erosion and infiltration of water into a simulated trench cap with various surface treatments were measured, and the interaction between erosion control and subsurface water dynamics is discussed relative to waste management.

  9. Efficient, Off-Grid LiDAR Scanning of Remote Field Sites

    NASA Astrophysics Data System (ADS)

    Gold, P.; Gold, R.; Cowgill, E.; Kreylos, O.; Hamann, B.

    2007-12-01

    As terrestrial LiDAR scanning systems become increasingly available, strategies for executing efficient field surveys in settings without access to the power grid are increasingly needed. To evaluate scan methods and develop an off-grid power system, we used a tripod-mounted laser scanner to create high resolution (≤40 mm point spacing) topographic maps for use in neotectonic studies of active faulting in arid, high elevation settings. We required 1-2 cm internal precision within point clouds spanning field sites that were ~300 x 300 m. Main components of our survey system included a Trimble GX DR200+ terrestrial laser scanner, a Leica TCR407power total station, a ruggedized laptop (2 GB RAM, 2.33 GHz dual-processor, and an Intel GMA 950 graphics card), batteries, and a portable photovoltaic array. Our first goal was to develop an efficient field-survey workflow. We started each survey project by using the total station for 1-2 days to locate an average of 8 ground control locations per site and to measure key geomorphic features within the project area. We then used the laser scanner to capture overlapping scans of the site, which required an average of six, 5-hour scanning sessions and an average of ten station setups. At each station, the scanner located itself on a particular point by measuring the relative positions of an average of four backsights, each of which is a ~17 x 17cm reflective target mounted on a tripod over the ground control point. To locate the scanner at a particular station prior to scanning, we experimented with both setting up over known points as measured using the total station, and resectioning, by positioning the scanner over an unmeasured location and backsighting on previously scanned points. We found that resectioning provided the smallest errors in scan registration. We then framed and queued a series of scans from each station that optimized point density and minimized data repetition. We also increased the accuracy of the

  10. SUPERFUND TREATABILITY CLEARINGHOUSE: SUMMARY REPORT ON THE FIELD INVESTIGATION OF THE SAPP BATTERY SITE JACKSON COUNTY, FLORIDA

    EPA Science Inventory

    This treatability study presents the results of field investigations at the Sapp Battery site in Florida, an abandoned battery recycling operation. The site is estimated to contain 14,300 cubic yards of soils with lead levels in excess of 1,000 ppm. The soils in the immediate v...

  11. Technical procedures for implementation of background environmental radioactivity site studies, Deaf Smith County site, Texas: Environmental Field Program: Preliminary draft

    SciTech Connect

    Not Available

    1987-09-01

    The purpose of this technical procedure is to describe the method for performing field maintenance on low-volume air samplers and the associated topics of personnel and organization, procedure preparation, documentation, and quality assurance. The scope of this procedure includes the maintenance of low-volume air samplers in the field and does not encompass maintenance performed by the manufacturer.

  12. The actual goals of geoethics

    NASA Astrophysics Data System (ADS)

    Nemec, Vaclav

    2014-05-01

    The most actual goals of geoethics have been formulated as results of the International Conference on Geoethics (October 2013) held at the geoethics birth-place Pribram (Czech Republic): In the sphere of education and public enlightenment an appropriate needed minimum know how of Earth sciences should be intensively promoted together with cultivating ethical way of thinking and acting for the sustainable well-being of the society. The actual activities of the Intergovernmental Panel of Climate Changes are not sustainable with the existing knowledge of the Earth sciences (as presented in the results of the 33rd and 34th International Geological Congresses). This knowledge should be incorporated into any further work of the IPCC. In the sphere of legislation in a large international co-operation following steps are needed: - to re-formulate the term of a "false alarm" and its legal consequences, - to demand very consequently the needed evaluation of existing risks, - to solve problems of rights of individuals and minorities in cases of the optimum use of mineral resources and of the optimum protection of the local population against emergency dangers and disasters; common good (well-being) must be considered as the priority when solving ethical dilemmas. The precaution principle should be applied in any decision making process. Earth scientists presenting their expert opinions are not exempted from civil, administrative or even criminal liabilities. Details must be established by national law and jurisprudence. The well known case of the L'Aquila earthquake (2009) should serve as a serious warning because of the proven misuse of geoethics for protecting top Italian seismologists responsible and sentenced for their inadequate superficial behaviour causing lot of human victims. Another recent scandal with the Himalayan fossil fraud will be also documented. A support is needed for any effort to analyze and to disclose the problems of the deformation of the contemporary

  13. Distinguishing 'new' from 'old' organic carbon in reclaimed coal mine sites using thermogravimetry: II. Field validation

    SciTech Connect

    Maharaj, S.; Barton, C.D.; Karathanasis, T.A.D.; Rowe, H.D.; Rimmer, S.M.

    2007-04-15

    Thermogravimetry was used under laboratory conditions to differentiate 'new' and 'old' organic carbon (c) by using grass litter, coal, and limestone to represent the different C fractions. Thermogravimetric and derivative thermogravimetry curves showed pyrolysis peaks at distinctively different temperatures, with the peak for litter occurring at 270 to 395{sup o}C, for coal at 415 to 520 {sup o}C, and for limestone at 700 to 785{sup o}C. To validate this method in a field setting, we studied four reforested coal mine sites in Kentucky representing a chronosequence since reclamation: 0 and 2 years located at Bent Mountain and 3 and 8 years located at the Starfire mine. A nonmined mature (approximate to 80 years old) stand at Robinson Forest, Kentucky, was selected as a reference location. Results indicated a general peak increase in the 270 to 395{sup o}C region with increased time, signifying an increase in the 'new' organic matter (OM) fraction. For the Bent Mountain site, the OM fraction increased from 0.03 to 0.095% between years 0 and 2, whereas the Starfire site showed an increase from 0.095 to 1.47% between years 3 and 8. This equates to a C sequestration rate of 2.92 Mg ha{sup -1} yr{sup -1} for 'new' OM in the upper 10-cm layer during the 8 years of reclamation on eastern Kentucky reclaimed coal mine sites. Results suggest that stable isotopes and elemental data can be used as proxy tools for qualifying soil organic C (SOC) changes over time on the reclaimed coal mine sites but cannot be used to determine the exact SOC accumulation rate. However, results suggested that the thermogravimetric and derivative thermogravimetry methods can be used to quantify SOC accumulation and has the potential to be a more reliable, cost-effective, and rapid means to determine the new organic C fraction in mixed geological material, especially in areas dominated by coal and carbonate materials.

  14. Preliminary results of numerical investigations at SECARB Cranfield, MS field test site

    NASA Astrophysics Data System (ADS)

    Choi, J.; Nicot, J.; Meckel, T. A.; Chang, K.; Hovorka, S. D.

    2008-12-01

    The Southeast Regional Carbon Sequestration partnership sponsored by DOE has chosen the Cranfield, MS field as a test site for its Phase II experiment. It will provide information on CO2 storage in oil and gas fields, in particular on storage permanence, storage capacity, and pressure buildup as well as on sweep efficiency. The 10,300 ft-deep reservoir produced 38 MMbbl of oil and 677 MMSCF of gas from the 1940's to the 1960's and is being retrofitted by Denbury Resources for tertiary recovery. CO2 injection started in July 2008 with a scheduled ramp up during the next few months. The Cranfield modeling team selected the northern section of the field for development of a numerical model using the multiphase-flow, compositional CMG-GEM software. Model structure was determined through interpretation of logs from old and recently-drilled wells and geophysical data. PETREL was used to upscale and export permeability and porosity data to the GEM model. Preliminary sensitivity analyses determined that relative permeability parameters and oil composition had the largest impact on CO2 behavior. The first modeling step consisted in history-matching the total oil, gas, and water production out of the reservoir starting from its natural state to determine the approximate current conditions of the reservoir. The fact that pressure recovered in the 40 year interval since end of initial production helps in constraining boundary conditions. In a second step, the modeling focused on understanding pressure evolution and CO2 transport in the reservoir. The presentation will introduce preliminary results of the simulations and confirm/explain discrepancies with field measurements.

  15. Field test of infrared thermography applied to biogas controlling in landfill sites

    NASA Astrophysics Data System (ADS)

    Madruga, Francisco J.; Muñoz, Jaime M.; González, Daniel A.; Tejero, Juan I.; Cobo, Adolfo; Gil, José L.; Conde, Olga M.; López-Higuera, Jose M.

    2007-04-01

    The gases accumulated inside the landfill as result of the fermentation of Municipal Solid Waste (MSW) known as biogas, are taking into consideration all possible uses as direct transformation into electricity. The system for collecting, regulating and controlling the biogas must include all the necessary safety features where the biogas leakage presents a high impact. Infrared thermography can be use to detect gas leakages due to the differences in temperature between the gas and the immediate surroundings. This method is able to monitor a wide area of landfill sites, quickly. This technology will not be effective if the differences in temperature are not better than five degrees. This paper describes a field test conducted to study the limitations of the infrared thermography caused by weather conditions and the moment of day or/and season when the thermal images was captured. Pipelines, borders, cells, covers, slopes and leakage (hot spots) are studied and optimum conditions are defined.

  16. Wind Field Predictions for the Columbia Gorge and the Goodnoe Hills Wind Turbine Site.

    SciTech Connect

    Veenhuizen, Scott D.; Lin, Jung-Tai.

    1980-08-01

    Numerical estimates of the long term seasonal mean wind speeds, wind directions, and available wind power density were conducted for comparison with the results of field wind measurements obtained by the Bonneville Power Administration for the Columbia Gorge region along the Oregon-Washngton border. The authors had previously used the numerical method of estimating wind flows in complex terrain to identify high wind energy areas within the Olympic Peninsula and Northern Cascade regions of the State of Washington. The numerical technique was used as a generalized wind prospecting tool to provide the link between regional assessments and on-site biological or geomorphological indicators of mean wind speeds and available wind energy. The wind flow model used is a two dimensional model based upon simplified hydrodynamical equations describing the fluid and thermodynamic motion of the atmosphere.

  17. Low and high field sites of Cr3+ ions in calcium tetraborate glasses

    NASA Astrophysics Data System (ADS)

    Lesniewski, T.; Padlyak, B. V.; Barzowska, J.; Mahlik, S.; Adamiv, V. T.; Nurgul, Z.; Grinberg, M.

    2016-09-01

    This paper presents electron paramagnetic resonance and detailed optical spectroscopic characterization of CaB4O7 glasses doped with Cr3+. The luminescence excitation spectrum consists of two broad bands related to transitions from the ground state 4A2g to the excited states 4T1g and 4T2g of the octahedrally coordinated Cr3+ ions. The photoluminescence spectrum is a superposition of the R line related to the 2Eg → 4A2g transition and broad band related to the 4T2g → 4A2g transition. The analysis of electron paramagnetic resonance spectra allowed to distinguish different Cr3+ sites, whereas the analysis of luminescence and luminescence excitation spectra allowed to characterize the crystal field distribution in the glass host.

  18. Trends of Abutment-Scour Prediction Equations Applied to 144 Field Sites in South Carolina

    USGS Publications Warehouse

    Benedict, Stephen T.; Deshpande, Nikhil; Aziz, Nadim M.; Conrads, Paul A.

    2006-01-01

    The U.S. Geological Survey conducted a study in cooperation with the Federal Highway Administration in which predicted abutment-scour depths computed with selected predictive equations were compared with field measurements of abutment-scour depth made at 144 bridges in South Carolina. The assessment used five equations published in the Fourth Edition of 'Evaluating Scour at Bridges,' (Hydraulic Engineering Circular 18), including the original Froehlich, the modified Froehlich, the Sturm, the Maryland, and the HIRE equations. An additional unpublished equation also was assessed. Comparisons between predicted and observed scour depths are intended to illustrate general trends and order-of-magnitude differences for the prediction equations. Field measurements were taken during non-flood conditions when the hydraulic conditions that caused the scour generally are unknown. The predicted scour depths are based on hydraulic conditions associated with the 100-year flow at all sites and the flood of record for 35 sites. Comparisons showed that predicted scour depths frequently overpredict observed scour and at times were excessive. The comparison also showed that underprediction occurred, but with less frequency. The performance of these equations indicates that they are poor predictors of abutment-scour depth in South Carolina, and it is probable that poor performance will occur when the equations are applied in other geographic regions. Extensive data and graphs used to compare predicted and observed scour depths in this study were compiled into spreadsheets and are included in digital format with this report. In addition to the equation-comparison data, Water-Surface Profile Model tube-velocity data, soil-boring data, and selected abutment-scour data are included in digital format with this report. The digital database was developed as a resource for future researchers and is especially valuable for evaluating the reasonableness of future equations that may be developed.

  19. Phenotypic and Genotypic Comparison of Symbiotic and Free-Living Cyanobacteria from a Single Field Site

    PubMed Central

    West, N. J.; Adams, D. G.

    1997-01-01

    PCR amplification techniques were used to compare cyanobacterial symbionts from a cyanobacterium-bryophyte symbiosis and free-living cyanobacteria from the same field site. Thirty-one symbiotic cyanobacteria were isolated from the hornwort Phaeoceros sp. at several closely spaced locations, and 40 free-living cyanobacteria were isolated from the immediate vicinity of the same plants. One of the symbiotic isolates was a species of Calothrix, a genus not previously known to form bryophyte symbioses, and the remainder were Nostoc spp. Of the free-living strains, two were Calothrix spp., three were Chlorogloeopsis spp. and the rest were Nostoc spp. All of the symbiotic and all but one of the free-living strains were able to reconstitute the symbiosis with axenic cultures of both Phaeoceros and the liverwort Blasia sp. Axenic cyanobacterial strains were compared by DNA amplification using PCR with either short arbitrary primers or primers specific for the regions flanking the 16S-23S rRNA internal transcribed spacer. With one exception, the two techniques produced complementary results and confirmed for the first time that a diversity of symbiotic cyanobacteria infect Phaeoceros in the field. Symbionts from adjacent colonies were different as often as they were the same, showing that the same thallus could be infected with many different cyanobacterial strains. Strains found to be identical by the techniques employed here were often found as symbionts in different thalli at the same locale but were never found free-living. Only one of the free-living strains, and none of the symbiotic strains, was found at more than one sample site, implying a highly localized distribution of strains. PMID:16535734

  20. Personal UV exposure on a ski-field at an alpine site

    NASA Astrophysics Data System (ADS)

    Siani, A. M.; Casale, G. R.; Diémoz, H.; Agnesod, G.; Kimlin, M. G.; Lang, C. A.; Colosimo, A.

    2008-02-01

    Mountain sites experience enhanced ambient UV radiation levels due to the concurrent effects of shorter radiation path-length, low aerosol load and high reflectivity of the snow surfaces. This study was encouraged by the possibility to collect data of personal UV exposure in the mountainous areas of Italy, for the first time. Personal UV exposure (expressed in terms of Exposure Ratio, ER) of two groups of volunteers (ski instructors and skiers) at the Alpine site of La Thuile (Valle d'Aosta region, Italy) was assessed using polysulphone dosimetry which was tested in a mountainous snow-covered environment. In addition measurements of biological markers of individual response to UV exposure such as skin colorimetric parameters were carried out. It was found that snow and altitude of study site affect calibration curves of polysulphone dosimeters in comparison to a situation without snow. The median ER, taking into account the whole sample, is 0.60 in winter, with a range of 0.29 to 1.46, and 1.02 in spring, ranging from 0.46 to 1.72. There are no differences in exposures across skiers and instructors in spring while in winter skiers experience lower values. UV exposures are not sensitive to the use of sunscreen across instructor/skier group by day or by seasons or by photo-type. With regard to colorimetric parameters, the main result was that both skiers and instructors had on average significantly lower values of L* and b* after exposure i.e. becoming darker but the inappropriate sunscreen use did not reveal any changes in skin colorimetric parameters except in one spring day. In conclusions UV intensities on the ski-fields are often significantly higher than those on horizontal surfaces. Given the high levels of exposure observed in the present study, dedicated public heath messages on the correct sunscreen use should be adopted.

  1. Spatial distribution of an uranium-respiring betaproteobacterium at the Rifle, CO field research site

    DOE PAGES

    Koribanics, Nicole M.; Tuorto, Steven J.; Lopez-Chiaffarelli, Nora; McGuinness, Lora R.; Häggblom, Max M.; Williams, Kenneth H.; Long, Philip E.; Kerkhof, Lee J.; Morais, Paula V

    2015-04-13

    The Department of Energy’s Integrated Field-Scale Subsurface Research Challenge Site (IFRC) at Rifle, Colorado was created to address the gaps in knowledge on the mechanisms and rates of U(VI) bioreduction in alluvial sediments. Previous studies at the Rifle IFRC have linked microbial processes to uranium immobilization during acetate amendment. Several key bacteria believed to be involved in radionuclide containment have been described; however, most of the evidence implicating uranium reduction with specific microbiota has been indirect. Here, we report on the cultivation of a microorganism from the Rifle IFRC that reduces uranium and appears to utilize it as a terminalmore » electron acceptor for respiration with acetate as electron donor. Furthermore, this bacterium constitutes a significant proportion of the subsurface sediment community prior to biostimulation based on TRFLP profiling of 16S rRNA genes. 16S rRNA gene sequence analysis indicates that the microorganism is a betaproteobacterium with a high similarity to Burkholderia fungorum. This is, to our knowledge, the first report of a betaproteobacterium capable of uranium respiration. Our results indicate that this microorganism occurs commonly in alluvial sediments located between 3-6 m below ground surface at Rifle and may play a role in the initial reduction of uranium at the site.« less

  2. Salton Sea Geothermal Field, Imperial Valley, California as a site for continental scientific drilling. [Abstract only

    SciTech Connect

    Elders, W.A.; Cohen, L.H.

    1983-03-01

    The Salton Trough, where seafloor spreading systems of the East Pacific Rise transition into the San Andreas transform fault system, is the site of such continental rifting and basin formation today. The largest thermal anomaly in the trough, the Salton Sea Geothermal Field (SSGF), is of interest to both thermal regimes and mineral resources investigators. At this site, temperatures >350/sup 0/C and metal-rich brines with 250,000 mg/L TDS have been encountered at <2 km depth. Republic Geothermal Inc. will drill a new well to 3.7 km in the SSGF early in 1983; we propose add-on experiments in it. If funded, we will obtain selective water and core samples and a large-diameter casing installed to 3.7 km will permit later deepening. In Phase 2, the well would be continuously cored to 5.5 km and be available for scientific studies until July 1985. The deepened well would encounter hydrothermal regimes of temperature and pressure never before sampled.

  3. Dynamic temperature fields under Mars landing sites and implications for supporting microbial life.

    PubMed

    Ulrich, Richard; Kral, Tim; Chevrier, Vincent; Pilgrim, Robert; Roe, Larry

    2010-01-01

    While average temperatures on Mars may be too low to support terrestrial life-forms or aqueous liquids, diurnal peak temperatures over most of the planet can be high enough to provide for both, down to a few centimeters beneath the surface for some fraction of the time. A thermal model was applied to the Viking 1, Viking 2, Pathfinder, Spirit, and Opportunity landing sites to demonstrate the dynamic temperature fields under the surface at these well-characterized locations. A benchmark temperature of 253 K was used as a lower limit for possible metabolic activity, which corresponds to the minimum found for specific terrestrial microorganisms. Aqueous solutions of salts known to exist on Mars can provide liquid solutions well below this temperature. Thermal modeling has shown that 253 K is reached beneath the surface at diurnal peak heating for at least some parts of the year at each of these landing sites. Within 40 degrees of the equator, 253 K beneath the surface should occur for at least some fraction of the year; and, within 20 degrees , it will be seen for most of the year. However, any life-form that requires this temperature to thrive must also endure daily excursions to far colder temperatures as well as periods of the year where 253 K is never reached at all.

  4. The explosion sites of nearby supernovae seen with integral field spectroscopy

    NASA Astrophysics Data System (ADS)

    Kuncarayakti, Hanindyo

    2015-08-01

    The progenitor stars of supernovae are still not very well constrained, despite numerous efforts in studying these objects directly or indirectly. There have been detections of the progenitor candidates in pre-explosion Hubble Space Telescope images, but these are rare and it is difficult to increase the statistics due to the limited availability of usable pre-explosion images. Alternatively, one may perform statistical studies on the supernova environments to derive useful constraints on the SN progenitor star. Integral field spectroscopy of nearby supernova sites within ~30 Mpc have been obtained using multiple IFU spectrographs in Hawaii and Chile. This technique enables both spatial and spectral information of the explosion sites to be acquired simultaneously, thus providing the identification of the parent stellar population of the supernova progenitor and the estimates for its physical parameters including age and metallicity. While this work has mainly been done in the optical wavelengths using instruments such as VIMOS, GMOS, and MUSE, a near-infrared approach has also been carried out using the AO-assisted SINFONI. By studying the supernova parent stellar population, we aim to characterize the mass and metallicity of the progenitors of different types of supernovae.

  5. Spatial Distribution of an Uranium-Respiring Betaproteobacterium at the Rifle, CO Field Research Site

    PubMed Central

    Koribanics, Nicole M.; Tuorto, Steven J.; Lopez-Chiaffarelli, Nora; McGuinness, Lora R.; Häggblom, Max M.; Williams, Kenneth H.; Long, Philip E.; Kerkhof, Lee J.

    2015-01-01

    The Department of Energy’s Integrated Field-Scale Subsurface Research Challenge Site (IFRC) at Rifle, Colorado was created to address the gaps in knowledge on the mechanisms and rates of U(VI) bioreduction in alluvial sediments. Previous studies at the Rifle IFRC have linked microbial processes to uranium immobilization during acetate amendment. Several key bacteria believed to be involved in radionuclide containment have been described; however, most of the evidence implicating uranium reduction with specific microbiota has been indirect. Here, we report on the cultivation of a microorganism from the Rifle IFRC that reduces uranium and appears to utilize it as a terminal electron acceptor for respiration with acetate as electron donor. Furthermore, this bacterium constitutes a significant proportion of the subsurface sediment community prior to biostimulation based on TRFLP profiling of 16S rRNA genes. 16S rRNA gene sequence analysis indicates that the microorganism is a betaproteobacterium with a high similarity to Burkholderia fungorum. This is, to our knowledge, the first report of a betaproteobacterium capable of uranium respiration. Our results indicate that this microorganism occurs commonly in alluvial sediments located between 3-6 m below ground surface at Rifle and may play a role in the initial reduction of uranium at the site. PMID:25874721

  6. Pitch-Angle Distribution for Electrons at Dipolarization Sites: Field Aligned Anisotropy and Isotropization

    NASA Astrophysics Data System (ADS)

    Wang, K.; Lin, C. H.; Hada, T.; Nishimura, T.; Angelopoulos, V.; Lee, W. J.; Lang, Z. R.

    2015-12-01

    Investigation of Earth's radiation environment is important not only because of its geophysical significance but also because it can inform the design of future satellites. The observed dipolarization effects on pitch-angle distributions (PAD) of electrons at the tailside in the inner plasmasheet during geomagnetic activity identified by AL index has been studied via analyzing data from THEMIS mission. We have shown that cigar distributions below about 1keV tend to become isotropized at the fronts at the dipolarization sites whereas isotropic distributions above 1keV tend to become more cigar-shaped (i.e., fluxes peak at pitch-angle of 0o and 180o). We have previously suggested that the ineffectiveness of Fermi acceleration below 1keV could be the factor causing this difference. We examine the dependence of this effect on radial distance from Earth taking place at or near dipolarization sites during times of geomagnetic activity. Because both the field line length and the properties of dipolarizations vary with radial distance. We anticipate significant dependence of this effect on radial distance. Our study contributes to our understanding of the electron environment during dipolarizations in Earth's magnetosphere.

  7. Spatial distribution of an uranium-respiring betaproteobacterium at the Rifle, CO field research site

    SciTech Connect

    Koribanics, Nicole M.; Tuorto, Steven J.; Lopez-Chiaffarelli, Nora; McGuinness, Lora R.; Häggblom, Max M.; Williams, Kenneth H.; Long, Philip E.; Kerkhof, Lee J.; Morais, Paula V

    2015-04-13

    The Department of Energy’s Integrated Field-Scale Subsurface Research Challenge Site (IFRC) at Rifle, Colorado was created to address the gaps in knowledge on the mechanisms and rates of U(VI) bioreduction in alluvial sediments. Previous studies at the Rifle IFRC have linked microbial processes to uranium immobilization during acetate amendment. Several key bacteria believed to be involved in radionuclide containment have been described; however, most of the evidence implicating uranium reduction with specific microbiota has been indirect. Here, we report on the cultivation of a microorganism from the Rifle IFRC that reduces uranium and appears to utilize it as a terminal electron acceptor for respiration with acetate as electron donor. Furthermore, this bacterium constitutes a significant proportion of the subsurface sediment community prior to biostimulation based on TRFLP profiling of 16S rRNA genes. 16S rRNA gene sequence analysis indicates that the microorganism is a betaproteobacterium with a high similarity to Burkholderia fungorum. This is, to our knowledge, the first report of a betaproteobacterium capable of uranium respiration. Our results indicate that this microorganism occurs commonly in alluvial sediments located between 3-6 m below ground surface at Rifle and may play a role in the initial reduction of uranium at the site.

  8. Controlled soil warming powered by alternative energy for remote field sites.

    PubMed

    Johnstone, Jill F; Henkelman, Jonathan; Allen, Kirsten; Helgason, Warren; Bedard-Haughn, Angela

    2013-01-01

    Experiments using controlled manipulation of climate variables in the field are critical for developing and testing mechanistic models of ecosystem responses to climate change. Despite rapid changes in climate observed in many high latitude and high altitude environments, controlled manipulations in these remote regions have largely been limited to passive experimental methods with variable effects on environmental factors. In this study, we tested a method of controlled soil warming suitable for remote field locations that can be powered using alternative energy sources. The design was tested in high latitude, alpine tundra of southern Yukon Territory, Canada, in 2010 and 2011. Electrical warming probes were inserted vertically in the near-surface soil and powered with photovoltaics attached to a monitoring and control system. The warming manipulation achieved a stable target warming of 1.3 to 2 °C in 1 m(2) plots while minimizing disturbance to soil and vegetation. Active control of power output in the warming plots allowed the treatment to closely match spatial and temporal variations in soil temperature while optimizing system performance during periods of low power supply. Active soil heating with vertical electric probes powered by alternative energy is a viable option for remote sites and presents a low-disturbance option for soil warming experiments. This active heating design provides a valuable tool for examining the impacts of soil warming on ecosystem processes.

  9. Construction of a photocatalytic de-polluting field site in the Leopold II tunnel in Brussels.

    PubMed

    Boonen, E; Akylas, V; Barmpas, F; Boréave, A; Bottalico, L; Cazaunau, M; Chen, H; Daële, V; De Marco, T; Doussin, J F; Gaimoz, C; Gallus, M; George, C; Grand, N; Grosselin, B; Guerrini, G L; Herrmann, H; Ifang, S; Kleffmann, J; Kurtenbach, R; Maille, M; Manganelli, G; Mellouki, A; Miet, K; Mothes, F; Moussiopoulos, N; Poulain, L; Rabe, R; Zapf, P; Beeldens, A

    2015-05-15

    Within the framework of the European Life+-funded project PhotoPAQ (Demonstration of Photocatalytic remediation Processes on Air Quality), which was aimed at demonstrating the effectiveness of photocatalytic coating materials on a realistic scale, a photocatalytic de-polluting field site was set up in the Leopold II tunnel in Brussels, Belgium. For that purpose, photocatalytic cementitious materials were applied on the side walls and ceiling of selected test sections inside a one-way tunnel tube. This article presents the configuration of the test sections used and the preparation and implementation of the measuring campaigns inside the Leopold II tunnel. While emphasizing on how to implement measuring campaigns under such conditions, difficulties encountered during these extensive field campaigns are presented and discussed. This included the severe de-activation observed for the investigated material under the polluted tunnel conditions, which was revealed by additional laboratory experiments on photocatalytic samples that were exposed to tunnel air. Finally, recommendations for future applications of photocatalytic building materials inside tunnels are given.

  10. Controlled soil warming powered by alternative energy for remote field sites.

    PubMed

    Johnstone, Jill F; Henkelman, Jonathan; Allen, Kirsten; Helgason, Warren; Bedard-Haughn, Angela

    2013-01-01

    Experiments using controlled manipulation of climate variables in the field are critical for developing and testing mechanistic models of ecosystem responses to climate change. Despite rapid changes in climate observed in many high latitude and high altitude environments, controlled manipulations in these remote regions have largely been limited to passive experimental methods with variable effects on environmental factors. In this study, we tested a method of controlled soil warming suitable for remote field locations that can be powered using alternative energy sources. The design was tested in high latitude, alpine tundra of southern Yukon Territory, Canada, in 2010 and 2011. Electrical warming probes were inserted vertically in the near-surface soil and powered with photovoltaics attached to a monitoring and control system. The warming manipulation achieved a stable target warming of 1.3 to 2 °C in 1 m(2) plots while minimizing disturbance to soil and vegetation. Active control of power output in the warming plots allowed the treatment to closely match spatial and temporal variations in soil temperature while optimizing system performance during periods of low power supply. Active soil heating with vertical electric probes powered by alternative energy is a viable option for remote sites and presents a low-disturbance option for soil warming experiments. This active heating design provides a valuable tool for examining the impacts of soil warming on ecosystem processes. PMID:24386125

  11. Investigation of well redevelopment techniques for the MWD Well Field, Savannah River Site, South Carolina

    SciTech Connect

    Kroening, D.E.; Snipes, D.S.; Falta, R.W.; Benson, S.M. . Dept. of Earth Sciences); Janssen, J. )

    1994-03-01

    Clemson University, in cooperation with the Savannah River Site (SRS) is investigating well treatment techniques at the Mixed Waste Disposal (MWD) Well Field at SRS. This well field consists of fifteen wells screened in three aquifers with a downward trending head gradient. Based on aquifer performance tests of the MWD wells, it has been determined that many of the wells exhibit low well efficiencies and high skin factors, indicative of damaged wells. Bacterial investigations show that the biological activity in these wells is low, probably due to a high pH environment. Evaluation of the Calcite Saturation Index for each well indicates that nearly all of the MWD wells have the potential for precipitating calcite and calcite deposits have been observed on downhole equipment. The calcite deposits may occur due to the dissolution of the grout mixtures by waters infiltrating down the well annulus driven by the downward head gradient with subsequent precipitation of calcite in the higher pH sand pack. Well rehabilitation techniques currently under investigation include acidification, hydraulic fracturing and traditional physical methods. In addition to treating the wells at MWD, the authors plan to perform aquifer performance tests and evaluate post-treatment skin factors. Further research into the long term effects of well treatment will be conducted, focusing on long term chemical changes brought about by the treatments.

  12. Controlled Soil Warming Powered by Alternative Energy for Remote Field Sites

    PubMed Central

    Johnstone, Jill F.; Henkelman, Jonathan; Allen, Kirsten; Helgason, Warren; Bedard-Haughn, Angela

    2013-01-01

    Experiments using controlled manipulation of climate variables in the field are critical for developing and testing mechanistic models of ecosystem responses to climate change. Despite rapid changes in climate observed in many high latitude and high altitude environments, controlled manipulations in these remote regions have largely been limited to passive experimental methods with variable effects on environmental factors. In this study, we tested a method of controlled soil warming suitable for remote field locations that can be powered using alternative energy sources. The design was tested in high latitude, alpine tundra of southern Yukon Territory, Canada, in 2010 and 2011. Electrical warming probes were inserted vertically in the near-surface soil and powered with photovoltaics attached to a monitoring and control system. The warming manipulation achieved a stable target warming of 1.3 to 2°C in 1 m2 plots while minimizing disturbance to soil and vegetation. Active control of power output in the warming plots allowed the treatment to closely match spatial and temporal variations in soil temperature while optimizing system performance during periods of low power supply. Active soil heating with vertical electric probes powered by alternative energy is a viable option for remote sites and presents a low-disturbance option for soil warming experiments. This active heating design provides a valuable tool for examining the impacts of soil warming on ecosystem processes. PMID:24386125

  13. Hurricane Sandy's Fingerprint: Ripple Bedforms at an Inner Continental Shelf Sorted Bedform Field Site

    NASA Astrophysics Data System (ADS)

    DuVal, C.; Trembanis, A. C.; Beaudoin, J. D.; Schmidt, V. E.; Mayer, L. A.

    2013-12-01

    The hydrodynamics and seabed morphodynamics on the inner continental shelf and near shore environments have increasing relevance with continued development of near shore structures, offshore energy technologies and artificial reef construction. Characterizing the stresses on and response of the seabed near and around seabed objects will inform best practices for structural design, seabed mine and unexploded ordnance detection, and archaeological and benthic habitat studies. As part of an ONR funded project, Delaware's Redbird Reef is being studied for object scour and sorted bedform morphodynamics (Trembanis et al., in press). Central to this study are the effects of large storm events, such as Hurricane Sandy, which have had significant impact on the seafloor. Previous studies of inner shelf bedform dynamics have typically focused on near bed currents and bed stressors (e.g. Trembanis et al., 2004), sorted bedforms (e.g. Green et al., 2004) and object scour (e.g. Quinn, 2006; Trembanis et al., 2007; Mayer et al., 2007), but our understanding of the direct effects of objects and object scour on bedform morphodynamics is still incomplete. With prominent sorted bedform ripple fields, the Delaware Redbird artificial reef site, composed of 997 former New York City subway cars, as well as various military vehicles, tugboats, barges and ballasted tires, has made an ideal study location (Raineault et al., 2013 and 2011). Acoustic mapping of the Redbird reef three days prior to Sandy and two days after the following nor'easter, captured the extensive effects of the storms to the site, while acoustic Doppler current profilers characterized both the waves and bottom currents generated by the storm events. Results of the post-Sandy survey support the theory of sorted bedform evolution proposed by Murray and Thieler (2004). Acoustic imagery analysis indicates a highly energized and mobile bed during the storms, leading to self-organization of bedforms and creation of large

  14. Impacts of Humic Injection Experiments on the South Oyster Field Research Site

    SciTech Connect

    John F. McCarthy

    2004-04-27

    A closure plan for the South Oyster Focus Area (SOFA) is being implemented to assess the impacts of a series of experimental injections of microorganisms, tracers and chemical amendments on the chemical and physical properties of the aquifer. The proposed research addresses environmental monitoring of humic substances injected into the aquifer, as described in the Site Closure Plan for the South Oyster Field Research Site. The goal of the research is to demonstrate that the dissolved organic matter (DOM) in the groundwater at and downgradient from the injection site has returned to a pre-injection �baseline� conditions with respect to either the concentration or chemical composition of the DOM. For clarity, the humic solution injected during the experiment will be referred to as �humic injectate.� The term �DOM� will refer to the organic material recovered in the groundwater, which includes the autochthonous groundwater DOM as well as any of the humic injectate remaining in the groundwater. Specific objectives include: � Estimate the amount of humic material remaining in the aquifer at the completion of the push-pull experiment and the potential for environmental impacts due to release of humics retained on the sediments. � Monitor the DOM concentrations in groundwater over time at the injection well and at sampling locations within the potential downgradient plume of the injected tracers. � Evaluate the chemical composition of the DOM to determine whether the injection experiment had an impact of the chemical properties of the aquifer. The product of this research will be a contribution to the Site Closure Report documenting the impact of the humic experiments on the aquifer. Return of the aquifer to a �baseline� conditions will be achieved if the DOM concentrations in the groundwater are determined over the course of the research to have decreased to the pre-injection level, or if the chemical properties of

  15. Diffuse versus discrete venting at the Tour Eiffel vent site, Lucky Strike hydrothermal field

    NASA Astrophysics Data System (ADS)

    Mittelstaedt, E. L.; Escartin, J.; Gracias, N.; Olive, J. L.; Barreyre, T.; Davaille, A. B.; Cannat, M.

    2010-12-01

    Two styles of fluid flow at the seafloor are widely recognized: (1) localized outflows of high temperature (>300°C) fluids, often black or grey color in color (“black smokers”) and (2) diffuse, lower temperature (<100°C), fluids typically transparent and which escape through fractures, porous rock, and sediment. The partitioning of heat flux between these two types of hydrothermal venting is debated and estimates of the proportion of heat carried by diffuse flow at ridge axes range from 20% to 90% of the total axial heat flux. Here, we attempt to improve estimates of this partitioning by carefully characterizing the heat fluxes carried by diffuse and discrete flows at a single vent site, Tour Eiffel in the Lucky Strike hydrothermal field along the Mid-Atlantic Ridge. Fluid temperature and video data were acquired during the recent Bathyluck’09 cruise to the Lucky Strike hydrothermal field (September, 2009) by Victor aboard “Pourquoi Pas?” (IFREMER, France). Temperature measurements were made of fluid exiting discrete vents, of diffuse effluents immediately above the seafloor, and of vertical temperature gradients within discrete hydrothermal plumes. Video data allow us to calculate the fluid velocity field associated with these outflows: for diffuse fluids, Diffuse Flow Velocimetry tracks the displacement of refractive index anomalies through time; for individual hydrothermal plumes, Particle Image Velocimetry tracks eddies by cross-correlation of pixels intensities between subsequent images. Diffuse fluids exhibit temperatures of 8-60°C and fluid velocities of ~1-10 cm s-1. Discrete outflows at 204-300°C have velocities of ~1-2 m s-1. Combined fluid flow velocities, temperature measurements, and full image mosaics of the actively venting areas are used to estimate heat flux of both individual discrete vents and diffuse outflow. The total integrated heat flux and the partitioning between diffuse and discrete venting at Tour Eiffel, and its

  16. Technical procedures for water resources: Volume 3, Environmental Field Program, Deaf Smith County Site, Texas: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    To ensure that the environmental field program comprehensively addresses the issues and requirements of the project, a site study plan (SSP) has been prepared for Water Resources (ONWI, 1987). This technical procedure (TP) has been developed to implement the field program described in the Water Resources Site Study Plan. This procedure provides the general method for the field collection of water and sediment samples from playa lakes using an Alpha horizontal type sampler or equivalent or a peristaltic pump for water and a KB-coring devise or ponar grab for sediments. The samples will be preserved and then shipped to a laboratory for analysis. The water quality and sediment samples will be collected as part of the surface-water quality field study described in the Site Plan for Water Resources. 15 refs., 5 figs., 3 tabs.

  17. Holocene geomagnetic field intensity variations: Contribution from the low latitude Canary Islands site

    NASA Astrophysics Data System (ADS)

    Kissel, C.; Laj, C.; Rodriguez-Gonzalez, A.; Perez-Torrado, F.; Carracedo, J. C.; Wandres, C.

    2015-11-01

    New absolute paleomagnetic intensity (PI) are investigated from 37 lava flows located at Tenerife and Gran Canaria (Canary Islands). They complete previously published directional results from the same flows and therefore allow to examine the time variations of the full geomagnetic vector. Twenty-eight flows are radiocarbon dated between 1706 AD and about 13 200 BC and one is historical. Eight other flows are not dated but they have stratigraphic links with the dated flows and archeomagnetic ages had been attributed to them based on their paleomagnetic directions. Various mineralogical analyses were conducted, giving access to the nature of the magnetic minerals and to their grain size. We performed the original Thellier and Thellier paleointensity (PI) experiments with a success rate of about 65% coupling this experiment with the strict set of selection criteria PICRIT-03. The mean PIs at the flow level are based on 3 to 12 independent PI determinations except for one site in which only one reliable determination could be obtained. The data indicate some variability in the local field intensity with a prominent PI peak centered around 600 BC and reaching 80 μT (VADM 16 ×1022 Am2), documented for the first time in this region. Combined with the published data obtained from western Africa, Spain, Portugal, Morocco and the Azores within a 2000 km-radius around the Canary Islands, our data allow to construct a curve illustrating the Earth magnetic field intensity fluctuations for Southwestern Europe/Western Africa. This curve, compared to the one produced for the Middle East and one calculated for Central Asia shows that maximum intensity patches have a very large geographical extent. They do not yet appear clearly in the models of variations of the dipolar field intensity.

  18. Petrophysical properties of saprolites from the Oak Ridge Integrated Field Research Challenge site, Tennessee

    SciTech Connect

    Revil, André; Skold, Magnus; Hubbard, Susan S.; Wu, Yuxin; Watson, David B.; Karaoulis, Marios

    2013-01-01

    At the Oak Ridge Integrated Field Research Challenge site, near Oak Ridge, Tennessee, the shallow saprolitic aquifer is contaminated by nitric acid, uranium, and metals originating from the former S3 settling ponds. To interpret low-frequency geophysical methods used to image contaminant plumes, we have characterized the petrophysical properties of three representative saprolite core samples. Their hydraulic conductivity ranges from to in agreement with field data. Complex conductivity measurements, in the frequency range of 1 mHz to 45 kHz, were performed with NaCl solutions with electrical conductivities in the range to , a range representative of field conditions. The electrical conductivity data were well reproduced with a simple linear conductivity model between the saprolite conductivity and the pore water conductivity. The conductivity plots were used to estimate the formation factor (the cementation exponent was about ) and the surface conductivity ( ). The magnitude of the surface conductivity depended on the degree of weathering and therefore on the amount of smectite and mixed layer (illite-smectite) clays present in the saprolite. The chargeability of the core samples was in the range of and is strongly dependent on the salinity. We also performed streaming potential measurements with the same pore fluid composition as that used for the complex conductivity measurements. We found an excess of movable electrical charges on the order of 100 to in agreement with previous investigations connecting the movable excess charge density to permeability. The zeta potential was in the range of to independent on the salinity. The electrical measurements were consistent with an average cation exchange capacity in the range of 1.4 to and a specific surface area on the order of 4000 to about 30,000 . Read More: http://library.seg.org/doi/abs/10.1190/geo2012-0176.1

  19. Pump-and-treat remediation of chlorinated solvent contamination at a controlled field-experiment site.

    PubMed

    Rivett, Michael O; Chapman, Steven W; Allen-King, Richelle M; Feenstra, Stanley; Cherry, John A

    2006-11-01

    Pump-and-treat (P&T) remediation and associated concentration tailing are investigated at the field scale in a mildly heterogeneous sandy aquifer through the extraction of dissolved chlorinated solvent plumes that had developed over 475 d from a multicomponent dense nonaqueous-phase liquid (DNAPL) source intentionally emplaced in the aquifer at the Borden (ON) research site. Extraction was accomplished via a source-containment well located 25 m from the source and two further downgradient plume-centerline wells to remove the advancing high-concentration dissolved plumes. The 550 days of detailed P&T field data demonstrated the following: remediation, albeit slowly, of the leading 25-60 m plume section to around typical drinking water standard concentrations; concentration tailing (reduction) over 4 orders of magnitude in the plume; a steady-state concentration "plateau" in the source-containment well capturing the steadily dissolving DNAPL source; influences of extraction rate changes (concentration rebounds); and, lengthy tailing from inter-well stagnation-zone areas. Much of the contaminant behavior during the P&T appeared to be "ideal" in the sense that with appropriate specification of the source term and pumping regime, it was reasonably predicted by 3-dimensional numerical model (HydroGeoSphere) simulations that assumed ideal (macrodispersion, linear sorption, etc.) transport. Supporting lab studies confirmed nonideal sorption was, however, important at the point sample scale with enhanced PCE (tetrachloroethene) sorption to low- and high-permeability strata and moderate nonlinear and competitive sorption influences. Although there was limited evidence of nonideal tailing contributions to the field data (underprediction of some tailing curve gradients), such contributions to P&T tailing were not easily discerned and appeared to play a relatively minor role within the mildly heterogeneous aquifer studied.

  20. Initial field trials of the site characterization and analysis penetrometer system (SCAPS). Reconnaissance of Jacksonville Naval Air Station waste oil and solvents disposal site. Final report

    SciTech Connect

    Cooper, S.S.; Douglas, D.H.; Sharp, M.K.; Olsen, R.A.; Comes, G.D.

    1993-12-01

    At the request of the Naval Facilities Engineering Command (NAVFAC), Southern Division, Charleston, SC, the U.S. Army Engineer Waterways Experiment Station (WES) conducted the initial field trial of the Site Characterization and Analysis Penetrometer System (SCAPS) at Jacksonville Naval Air Station (NAS), Jacksonville FL. This work was carried out by a field crew consisting of personnel from WES and the Naval Ocean Systems Center during the period of 16 July 1990 to 14 August 1990. The SCAPS investigation at the Jacksonville NAS has two primary objectives: (a) to provide data that could be useful in formulating remediation plans for the facility and (b) to provide for the initial field trial of the SCAPS currently under development by WES for the U.S. Army Toxic and Hazardous Materials Agency (USATHAMA), now the U.S. Army Environmental Center. The original concepts for the SCAPS was to develop an integrated site screening characterization system whose capabilities would include (a) surface mapping, (b) geophysical surveys using magnetic, induced electromagnetic, and radar instruments, (c) measurements of soil strength, soil electrical resistivity, and laser-induced soil fluorometry Cone penetrometer, Site Characterization and Analysis Laser Induced Fluorescence(LIF), Penetrometer System(SCAPS) POL Contamination, using screening instrumentation mounted in a soil penetrometer, (d) soil and fluid samplers, and (e) computerized data acquisition, interpretation, and visualization. The goal of the SCAPS program is to provide detailed, rapid, and cost-effective surface and subsurface data for input to site assessment/remediation efforts.

  1. Site study plan for Upper Aquifer Hydrology Clusters, Deaf Smith County Site, Texas: Surface-based geotechnical field program: Preliminary draft

    SciTech Connect

    Not Available

    1988-01-01

    As part of site characterization studies, at the Deaf Smith County site, Texas, 15 wells at 5 locations will be completed in the Ogallala Formation and Dockum Group. The purposes of the wells, which are called Upper Aquifer (2) establish background hydrologic and water quality conditions, (3) provide analysis, (4) monitor responses of the shallow hydrologic system to site activities and nearby pumpage for irrigation, (5) collect water samples from both saturated and unsaturated materials to help define recharge rates and ground-water flow patterns, (6) monitor variations on water quality, and (7) define ground-water resources near the site. The test wells will be installed during a 14-month period starting about 1-1/2 years after site characterization activities begin. The Technical Field Services Contractor is responsible for conducting the field program of drilling and testing. Samples and data will be handled and reported in accordance with established Salt Repository Project procedures. A quality assurance program will assure that activities affecting quality are performed correctly and that the appropriate documentation is maintained. 44 refs., 19 figs., 5 tabs.

  2. Linguistic Theory and Actual Language.

    ERIC Educational Resources Information Center

    Segerdahl, Par

    1995-01-01

    Examines Noam Chomsky's (1957) discussion of "grammaticalness" and the role of linguistics in the "correct" way of speaking and writing. It is argued that the concern of linguistics with the tools of grammar has resulted in confusion, with the tools becoming mixed up with the actual language, thereby becoming the central element in a metaphysical…

  3. El Observatorio Gemini - Status actual

    NASA Astrophysics Data System (ADS)

    Levato, H.

    Se hace una breve descripción de la situación actual del Observatorio Gemini y de las últimas decisiones del Board para incrementar la eficiencia operativa. Se hace también una breve referencia al uso argentino del observatorio.

  4. Field Summary Report for Remedial Investigation of Hanford Site Releases to the Columbia River, Hanford Site, Washington

    SciTech Connect

    L.C. Hulstrom

    2010-09-28

    This report documents field activity associated with the collection, preparation, and shipment of fish samples. The purpose of the report is to describe the sampling locations, identify samples collected, and describe any modifications and additions made to the sampling and analysis plan.

  5. Site study plan for Exploratory shaft facilities design foundation boreholes (shaft surface facility foundation borings), Deaf Smith County Site, Texas: Surface-based geotechnical field program: Preliminary draft

    SciTech Connect

    Not Available

    1987-12-01

    This site study plan describes the Exploratory Shaft Facilities (ESF) Design Foundation Boreholes field activities to be conducted during early stages of Site Characterization at the Deaf Smith County, Texas, site. The field program has been designed to provide data useful in addressing information/data needs resulting from federal/state/local regulations, and repository program requirements. Approximately 50 foundation boreholes will be drilled within the ESP location to provide data necessary for design of the ESF and to satisfy applicable shaft permitting requirements. Soils and subsurface rock will be sampled as the foundation boreholes are advanced. Soil samples or rock core will be taken through the Blackwater Draw and Ogallala Formations and the Dockum Group. Hydrologic testing will be performed in boreholes that penetrates the water table. In-situ elastic properties will be determined from both the soil strata and rock units along the length of the boreholes. Field methods/tests are chosen that provide the best or only means of obtaining the required data. The Salt Repository Project (SRP) Networks specify the schedule under which the program will operate. Drilling will not begin until after site ground water baseline conditions have been established. The Technical Field Services Contractor is responsible for conducting the field program of drilling and testing. Samples and data will be handled and reported in accordance with established SRP procedures. A quality assurance program will be utilized to assure that activities affecting quality are performed correctly and that the appropriate documentation is maintained. 25 refs., 10 figs., 6 tabs.

  6. Local fields at nonmagnetic impurity sites in a perovskite La 0 . 7 Ca 0 . 3 MnO 3

    NASA Astrophysics Data System (ADS)

    Sato, W.; Komatsuda, S.; Osa, A.; Sato, T. K.; Ohkubo, Y.

    2016-12-01

    The magnetic hyperfine field and electric field gradient at the 111Cd(leftarrow ^{111m}Cd) and 111Cd(leftarrow ^{111}In) probe nuclei introduced in a perovskite manganese oxide La0.7Ca0.3MnO3 ( T C ˜ 250 K) were measured for the study of the local magnetism and structure by means of time-differential perturbed angular correlation spectroscopy. In the ferromagnetic phase at 77 K, a very slight supertransferred magnetic hyperfine field (SMHF) (< 0.014 T) combined with a well-defined electric field gradient was observed at the nonmagnetic 111Cd nucleus on the La/Ca A site. This observation suggests that the large magnetic hyperfine field ( B h f = 6.9 T) measured, in our previous work, at the 140Ce probe nucleus on the A site originates from the contribution of a 4 f spin oriented by the SMHF from adjacent Mn ions.

  7. The effect of local anatomy on the electric field induced by TMS: evaluation at 14 different target sites.

    PubMed

    Janssen, Arno M; Oostendorp, Thom F; Stegeman, Dick F

    2014-10-01

    Many human cortical regions are targeted with transcranial magnetic stimulation (TMS). The stimulus intensity used for a certain region is generally based on the motor threshold stimulation intensity determined over the motor cortex (M1). However, it is well known that differences exist in coil-target distance and target site anatomy between cortical regions. These differences may well make the stimulation intensity derived from M1 sub-optimal for other regions. Our goal was to determine in what way the induced electric fields differ between cortical target regions. We used finite element method modeling to calculate the induced electric field for multiple target sites in a realistic head model. The effects on the electric field due to coil-target distance and target site anatomy have been quantified. The results show that a correction based on the distance alone does not correctly adjust the induced electric field for regions other than M1. In addition, a correction based solely on the TMS-induced electric field (primary field) does not suffice. A precise adjustment should include coil-target distance, the secondary field caused by charge accumulation at conductivity discontinuities and the direction of the field relative to the local cerebrospinal fluid-grey matter boundary.

  8. 3D and 4D GPR for Stratigraphic and Hydrologic Characterization of Field Sites

    NASA Astrophysics Data System (ADS)

    Grasmueck, M.; Viggiano, D. A.

    2008-05-01

    In a time of almost unlimited mobility, information, and connectivity it is surprising how our knowledge of natural systems becomes fragmented as soon as we enter the ground. Excavation, drilling, and 2D geophysics are unable to capture the spatio-temporal variability inside soil and rock volumes at the 1-10m scale. The problem is the lack of efficient and high-resolution imaging for the near surface domain. We have developed a high- resolution 3D Ground Penetrating Radar (GPR) system suitable for data acquisition at field sites. To achieve sharp and repeatable subsurface imaging we have integrated GPR with a rotary laser/IR strobe system. With 40 xyz coordinate updates per second, continuously moving GPR antennae can be tracked centimeter precise. A real-time LED guidance system shows the GPR antenna operator how to follow pre-computed survey tracks. Without having to stake out hundreds of survey tracks anymore one person now can scan an area of up to 600m2 per hour with a dual GPR antenna at 1m/s with 0.1m line spacing. The coordinate and GPR data are fused in real-time providing a first look of the subsurface in horizontal map view for quality control and in-field site assessment during data acquisition. The precision of the laser positioning system enables centimeter accurate repeat surveys to image and quantify water content changes in the vadose zone. To verify quantitative results of such 4D GPR we performed a controlled pond infiltration injecting 3200L of water from a 4x4m temporary pond with a thin soil layer and 5m of unsaturated porous limestone below. A total of sixteen repeated 3D GPR surveys were acquired just before the infiltration and in the following 2 weeks. All data were recorded with 250MHz antennae on a 5x10cm grid covering an area of 18x20m. Data processing included 3D migration and extraction of time shifts between pairs of time- lapse 3D GPR surveys. From the time shifts water content changes were computed using the Topp equation. The

  9. Aquifer recharge with reclaimed water in the Llobregat Delta. Laboratory batch experiments and field test site.

    NASA Astrophysics Data System (ADS)

    Tobella, J.

    2010-05-01

    on the conditions to develop at the test site during artificial recharge. The data collected during the laboratory experiments and in the test site will be used to build and calibrate a numerical model of the physical-chemical-biochemical processes developing in the batches and of multicomponent reactive transport in the unsaturated/saturated zone in the test site area. 3. Field test site The infiltration site of Sant Vicenç dels Horts has been selected to assessing the biogeochemical processes occurring during SAT. The system consists of two ponds that have been built as compensatory measure for the reduction in natural recharge caused by the construction of the High Speed Train Line. The first pond acts as a decantation pond while the second one acts as an infiltration basin (Figure 1). Recharge water comes from the tertiary treatment plant of the El Prat de Llobregat WWTP and the river (?). The CUADLL (Lower Llobregat Aquifer End-Users Community) is now managing the system operation. Tasks that are currently being carried out at this Test Site aims at (i) improving the local experience on MAR through infiltration ponds operational aspects and (ii) monitoring the changes in water quality during the recharge processes (unsaturated and saturated zone). Special attention is being paid to the fate of emerging organic pollutants (pharmaceuticals, surfactants, pesticides, etc.). The yielding of the monitoring will be compared with the results from the laboratory batch experiments on the behaviour of selected emerging organic pollutants. To this end, observation wells have been constructed, pressure / temperature / electrical conductivity transducers have been installed and the vadose zone under the infiltration pond has been instrumented (tensiometers, water content probes and suction cups). In addition double ring and infiltration tests have been performed in order to forecast the infiltration capacity of the basin.

  10. Research plan and preliminary results - A field research site for emerging contaminants in Iowa

    USGS Publications Warehouse

    Schnoebelen, Douglas J.; Kolpin, Dana W.; Barber, Larry B.; Furlong, Edward T.; Meyer, Michael; Skopec, M.

    2006-01-01

    Research has recently documented the prevalence of a wide variety of pharmaceuticals and other emerging contaminants (ECs) in streams across the United States. Wastewater treatment plants (WWTPs) have been found to be an important source and collection point of ECs to streams as many ECs are incompletely removed during treatment. To investigate the complex in-stream processes (e.g., dilution, sorption, degradation, dispersion, etc.) that can affect ECs following their input from a WWTP and determining if such input is having an effect on the aquatic ecosystem requires the integration of multi-disciplinary efforts at a carefully selected field site. Preliminary work has identified an 8-km reach of Fourmile Creek in central Iowa as an ideal research site to investigate such important research questions pertaining to ECs. Unique aspects of Fourmile Creek included: (1) it single source effluent-dominated stream, (2) background data document the input of a wide variety of ECs from WWTP discharge, (3) small basin size, (4) relatively simple flow system, (5) background data suggest that undefined processes are taking place decreasing the level of select ECs during stream transport, (6) the WWTP uses a treatment technology (activated sludge) typical of many towns in Iowa and the United States (7) a hydrogeologic setting of a low-gradient, small stream (average discharge less than 1.41 m³/s) in glacial drift is typical of many areas in Iowa and across the Midwest, and (8) the existence of a low-head clam approximately 2 km upstream of the WWTP outfall allowing more accurate "above WWTP" and "below WWTP" comparisons in aquatic ecosystems. Furthermore, the WWTP is scheduled to close by 2011 providing a unique opportunity to determine how stream hydrology, water chemistry and aquatic biota react to the removal of the primary source of flow and ECs in this system. This will allow a novel "before" and "after" assessment not previously available in EC research. Research to date

  11. Effects of Site-specific Application of Aldicarb on Cotton in a Meloidogyne incognita-infested Field

    PubMed Central

    Wrather, J. A.; Stevens, W. E.; Kirkpatrick, T. L.; Kitchen, N. R.

    2002-01-01

    Cotton farmers in Missouri commonly apply a single rate of aldicarb throughout the field at planting to protect their crop from Meloidogyne incognita, even though these nematodes are spatially aggregated. Our purpose was to determine the effect of site-specific application of aldicarb on cotton production in a field infested with these nematodes in 1997 and 1998. Cotton yields were collected from sites not treated with aldicarb (control), sites receiving aldicarb at the standard recommended rate of 0.58 kg a.i./ha, and sites receiving specific aldicarb rates based on the soil population densities of second-stage infective juveniles of root-knot nematode. Yields for the standard rate and site-specific rate treatments were similar and greater (P ≤ 0.05) than the control treatment. Less aldicarb was used for the site-specific than the uniform-rate treatment each year—46% less in 1997 and 61% less in 1998. Costs associated with the site-specific treatment were very high compared with the uniform-rate treatment due to a greater number of soil samples analyzed for nematodes. Site-specific application of aldicarb for root-knot nematode management in cotton may pose fewer environmental risks than the uniform-rate application of aldicarb. PMID:19265917

  12. Do release-site biases reflect response to the Earth's magnetic field during position determination by homing pigeons?

    PubMed Central

    Mora, Cordula V.; Walker, Michael M.

    2009-01-01

    How homing pigeons (Columba livia) return to their loft from distant, unfamiliar sites has long been a mystery. At many release sites, untreated birds consistently vanish from view in a direction different from the home direction, a phenomenon called the release-site bias. These deviations in flight direction have been implicated in the position determination (or map) step of navigation because they may reflect local distortions in information about location that the birds obtain from the geophysical environment at the release site. Here, we performed a post hoc analysis of the relationship between vanishing bearings and local variations in magnetic intensity using previously published datasets for pigeons homing to lofts in Germany. Vanishing bearings of both experienced and naïve birds were strongly associated with magnetic intensity variations at release sites, with 90 per cent of bearings lying within ±29° of the magnetic intensity slope or contour direction. Our results (i) demonstrate that pigeons respond in an orderly manner to the local structure of the magnetic field at release sites, (ii) provide a mechanism for the occurrence of release-site biases and (iii) suggest that pigeons may derive spatial information from the magnetic field at the release site that could be used to estimate their current position relative to their loft. PMID:19556255

  13. Quantum mechanical calculation of electric fields and vibrational Stark shifts at active site of human aldose reductase

    SciTech Connect

    Wang, Xianwei; Zhang, John Z. H.; He, Xiao

    2015-11-14

    Recent advance in biophysics has made it possible to directly measure site-specific electric field at internal sites of proteins using molecular probes with C = O or C≡N groups in the context of vibrational Stark effect. These measurements directly probe changes of electric field at specific protein sites due to, e.g., mutation and are very useful in protein design. Computational simulation of the Stark effect based on force fields such as AMBER and OPLS, while providing good insight, shows large errors in comparison to experimental measurement due to inherent difficulties associated with point charge based representation of force fields. In this study, quantum mechanical calculation of protein’s internal electrostatic properties and vibrational Stark shifts was carried out by using electrostatically embedded generalized molecular fractionation with conjugate caps method. Quantum calculated change of mutation-induced electric field and vibrational Stark shift is reported at the internal probing site of enzyme human aldose reductase. The quantum result is in much better agreement with experimental data than those predicted by force fields, underscoring the deficiency of traditional point charge models describing intra-protein electrostatic properties.

  14. Holocene geomagnetic field variations from low latitude site: contribution from the Canary Islands

    NASA Astrophysics Data System (ADS)

    Kissel, Catherine; Laj, Carlo; Rodriguez-Gonzalez, Alejandro; Perez-Torrado, Francisco; Carrracedo, Juan-Carlos; Wandres, Camille

    2016-04-01

    Full geomagnetic vector information was retrieved from 37 lava flows (corresponding to 38 sites because one flow was sampled at two different localities) located in Tenerife and Gran Canaria (Canary Islands). Twenty-eight flows are dated between 1706 AD and about 13200 BC and one is historical. Eight other non-dated flows have stratigraphic links with the dated flows and at the end, our study allowed us to attribute to them archeomagnetic ages based on their paleomagnetic characteristics. Various mineralogical analyses were conducted, giving access to the nature and grain size of the magnetic minerals. Full stepwise (about 13 steps) thermal and AF demagnetizations were conducted on more than 400 samples to determine the paleomagnetic directions. The individual MAD values are on the average about 2° and the mean precision parameter at the flow scale (alpha95) is 4.2°. For paleointensities (PI), we performed the original Thellier and Thellier experiments with a success rate of about 65%, coupling it with the strict set of selection criteria PICRIT-03. The mean PIs at the flow level are based on 3 to 12 independent PI determinations except for one site in which only one reliable determination could be obtained. The obtained data are unique in this area over the 1000-14000 BC period and they are complementary to the dataset obtained in the Canary Islands for the last 500 years. Over the last 3 kyr, they indicate some variability in the local field intensity with a prominent PI peak centered around 600 BC and reaching 80 μT (VADM 16 x 10 ^22 Am ^2), documented by four different flows and associated to significantly easterly deviated declinations. The directional data are rather consistent with the most recent models proposed for that area but the obtained PI indicate that models largely underestimate the paleointensities. Combined with published data obtained from western Africa, Spain, Portugal, Morocco and the Azores within a 2000 km-radius around the Canary

  15. Field experiment on CO2 back-production at the Ketzin pilot site

    NASA Astrophysics Data System (ADS)

    Martens, Sonja; Möller, Fabian; Schmidt-Hattenberger, Cornelia; Streibel, Martin; Szizybalski, Alexandra; Liebscher, Axel

    2015-04-01

    The operational phase of the Ketzin pilot site for geological CO2 storage in Germany started in June 2008 and ended in August 2013. Over the period of approximately five years, a total amount of 67 kt of CO2 was successfully injected into a saline aquifer (Upper Triassic sandstone) at a depth of 630 m - 650 m. The CO2 used was mainly of food grade quality. In addition, 1.5 kt of CO2 from the pilot capture facility "Schwarze Pumpe" (lignite power plant CO2) was used in 2011. At the end of the injection period, 32 t N2 and 613 t CO2 were co-injected during a four-week field test in July and August 2013. In October 2014, a field experiment was carried out at Ketzin with the aim to back-produce parts of the injected CO2 during a two-week period. This experiment addressed two main questions: (i) How do reservoir and wellbore behave during back-production of CO2? and (ii) What is the composition of the CO2 and the co-produced formation fluid? The back-production was carried out through the former injection well. It was conducted continuously over the first week and with an alternating regime including production during day-time and shut-ins during night-time in the second week. During the test, a total amount of 240 t of CO2 and 57 m3 of brine were safely back-produced from the reservoir. Production rates up to 3,200 kg/h - which corresponds to the former highest injection rate - could be tested. Vital monitoring parameters included production rates of CO2 and brine, wellhead and bottomhole pressure and temperature at the production and observation wells and distributed temperature sensing (DTS) along the production well. A permanently installed geoelectrical array was used for crosshole electrical resistivity tomography (ERT) monitoring of the reservoir. Formation fluid and gas samples were collected and analysed. The measured compositions allow studying the geochemical interactions between CO2, formation fluid and rocks under in-situ conditions The field experiment

  16. Building wake dispersion at an Arctic industrial site: Field tracer observations and plume model evaluations

    NASA Astrophysics Data System (ADS)

    Guenther, Alex; Lamb, Brian; Allwine, Eugene

    Ten multi-hour atmospheric dispersion SF 6 tracer experiments were conducted during October and November of 1987 near a large oil gathering facility in the Prudhoe Bay, Alaska, oilfield reservation. The purpose of this study was to investigate dispersion under arctic conditions and in situations where building-generated airflow disturbances dominate downwind distributions of ground level pollutant concentrations. This was accomplished with a network of micrometeorological instruments, portable syringe tracer samplers, continuous tracer analyzers, and infrared visualization of near source plume behavior. Atmospheric stability and wind speed profiles at this arctic site are influenced by the smooth (surface roughness = 0.03 cm), snow covered tundra surface which receives negligible levels of solar isolation in winter. The dispersion of pollutants emitted from sources within the oil gathering facility, however, is dominated by the influence of nearby buildings when high winds generate elevated ground level concentrations. An order of magnitude increase in maximum ground level concentration was observed as wind speeds increased from 5 to 8 m s -1 and another order of magnitude increase was observed as winds increased from 8 to 16 m s -1. Variation in maximum concentrations was also observed with changes in wind direction. Vertical plume diffusion ( σz) near the buildings was a factor of 2-3 greater than that observed in open terrain and was dependent on both wind speed and the projected building width and location of nearby buildings. Wind tunnel tracer distributions for east winds agree with field observations but also indicate that a significant increase in plume downwash occurs with other wind directions. Concentration distributions were calculated using several versions of the Industrial Source Complex (ISC) model. Model estimates of ground level concentrations were within a factor of three depending on wind direction. The model predictions are extremely sensitive

  17. Assessing field-scale migration of mobile radionuclides at the Nevada Test Site

    SciTech Connect

    Hu, Q; Rose, T P; Smith, D K; Moran, J E; Zavarin, M

    2006-09-26

    Numerous long-lived radionuclides, including {sup 99}Tc (technetium) and {sup 129}I (iodine), are present in groundwater at the Nevada Test Site (NTS) as a result of 828 underground nuclear weapons tests conducted between 1951 and 1992. We synthesize a body of groundwater data collected on the distribution of a number of radionuclides ({sup 3}H, {sup 14}C, {sup 36}Cl, {sup 99}Tc and {sup 129}I), which are presumably mobile in the subsurface and potentially toxic to down-gradient receptors, to assess their migration at NTS, at field scales over distances of hundreds of meters and for durations of more than thirty years. Qualitative evaluation of field-scale migration of these radionuclides in the saturated zone provides an independent approach to validating their presumably conservative transport in the performance assessment of the proposed geological repository at Yucca Mountain, which is located on the western edge of NTS. The analyses show that the interaction of {sup 3}H with a solid surface via an isotopic exchange with clay lattice hydroxyls may cause a slight delay in the transport of {sup 3}H. The transport of {sup 14}C could be retarded by its isotopic exchange with carbonate minerals, and the exchange may be more pronounced in the alluvial aquifer. In particular, {sup 99}Tc may not necessarily exist as a mobile and conservative species {sup 99}TcO{sub 4}{sup -}, as commonly assumed for NTS groundwater. This is corroborated with recent in situ redox potential measurements, both across and near Yucca Mountain, showing that groundwater at multiple locations is not oxidizing. Speciation of iodine and its associated reactivity and mobility is also complex in the groundwater at the NTS and deserves further attention. The assumption of no retardation for the transport of {sup 99}Tc (especially) and {sup 129}I, used at the performance assessment of Yucca Mountain repository, is probably overly conservative and results in unrealistically high estimated doses for

  18. A review of aerial radiological surveys of Nevada Test Site fallout fields 1951 through 1970

    SciTech Connect

    1987-12-01

    Aerial surveys of offsite fallout radiation fields from the Nevada Test Site began in the early 1950s and continued throughout the above-ground testing period. The results of the aerial surveys were used to support ground data in determining the extent of the fallout patterns. For the series of tests conducted in 1953 and 1955, the primary uncertainty of the results was knowing the location of the aircraft. Navigation was made from aeronautical charts of a scale 1:1,000,000, and errors in location of several miles were experienced. Another problem was that exposure rate readings made in the aircraft of 1 milliroentgen per hour or lower were not reliable. Exposure rate measurements above 1 milliroentgen per hour were more accurate, however, and are considered reliable to within a factor of two or three in predicting 3-foot exposure rate levels. For the 1957 series, the aircraft position data were quite accurate. Ground-level exposure rates predicted from aerial data obtained by the United States Geological Survey aircraft for the five-detector array were considered reliable to within +-40% or better for most of the surveys. When the single detector was used, the accuracy decreased to about a factor of two. Relative count rates obtained by the aircraft operated by the Atomic Energy Commission, Raw Materials Division, are probably valid, but quantitative determination of 3-foot exposure rates are not. The Aerial Radiological Monitoring System performed all the aerial surveys in the 1960s. However, the air-to-ground conversion factors used were too low. Using a corrected conversion factor, the predicted 3-foot exposure rates should be valid to +-40% in most fallout fields if all other parameters are considered. 40 refs., 30 figs., 6 tabs.

  19. Soil invertebrate community change over fuel-contaminated sites on a subantarctic island: An ecological field-based line of evidence for site risk assessment.

    PubMed

    Wasley, Jane; Mooney, Thomas J; King, Catherine K

    2016-04-01

    A number of fuel spills, of both recent and historic origins, have occurred on World Heritage-listed subantarctic Macquarie Island. Sites contaminated by mainly diesel fuels are undergoing remediation by the Australian Antarctic Division. The risks posed by these sites are being managed using a "weight of evidence" approach, for which this study provides a preliminary line of evidence for the ecological assessment component of this site management decision framework. This knowledge is pertinent, given the absence of environmental guidelines for fuel contaminants in subantarctic ecosystems. We provide a field-based, site-specific ecological risk assessment for soil invertebrate communities across the fuel spill sites, before the commencement of in situ remediation activities. Springtails (Collembola) were the most abundant taxa. Springtail community patterns showed only limited correlations with the level of fuel contamination at the soil surface, even when elevated levels occurred in the substratum layers. Of the environmental variables measured, community patterns were most strongly correlated with vegetation cover. We identify a suite of 6 species that contribute most to the community dynamics across these sites. A subset of these we propose as useful candidates for future development of single-species toxicity tests: Folsomotoma punctata, Cryptopygus caecus, Cryptopygus antarcticus and Parisotoma insularis. Findings from this study advance our understanding of soil invertebrate community dynamics within these contaminated sites, directly contributing to the improved management and restoration of the sites. Not only does this study provide an important line of evidence for the island's ecological risk assessment for fuel contaminants, it also enhances our understanding of the potential impact of fuels at other subantarctic islands. PMID:26202610

  20. Soil invertebrate community change over fuel-contaminated sites on a subantarctic island: An ecological field-based line of evidence for site risk assessment.

    PubMed

    Wasley, Jane; Mooney, Thomas J; King, Catherine K

    2016-04-01

    A number of fuel spills, of both recent and historic origins, have occurred on World Heritage-listed subantarctic Macquarie Island. Sites contaminated by mainly diesel fuels are undergoing remediation by the Australian Antarctic Division. The risks posed by these sites are being managed using a "weight of evidence" approach, for which this study provides a preliminary line of evidence for the ecological assessment component of this site management decision framework. This knowledge is pertinent, given the absence of environmental guidelines for fuel contaminants in subantarctic ecosystems. We provide a field-based, site-specific ecological risk assessment for soil invertebrate communities across the fuel spill sites, before the commencement of in situ remediation activities. Springtails (Collembola) were the most abundant taxa. Springtail community patterns showed only limited correlations with the level of fuel contamination at the soil surface, even when elevated levels occurred in the substratum layers. Of the environmental variables measured, community patterns were most strongly correlated with vegetation cover. We identify a suite of 6 species that contribute most to the community dynamics across these sites. A subset of these we propose as useful candidates for future development of single-species toxicity tests: Folsomotoma punctata, Cryptopygus caecus, Cryptopygus antarcticus and Parisotoma insularis. Findings from this study advance our understanding of soil invertebrate community dynamics within these contaminated sites, directly contributing to the improved management and restoration of the sites. Not only does this study provide an important line of evidence for the island's ecological risk assessment for fuel contaminants, it also enhances our understanding of the potential impact of fuels at other subantarctic islands.

  1. Field-Scale Migration of 99Tc and 129I at the Nevada Test Site

    SciTech Connect

    Hu, Q; Smith, D K

    2004-03-29

    The groundwater at the Nevada Test Site (NTS) contains many long-lived radionuclides, including {sup 99}Tc (technetium) and {sup 129}I (iodine), as a result of 828 underground nuclear weapons tests conducted between 1951 and 1992. We synthesized a body of data collected on the distribution of {sup 99}Tc and {sup 129}I in groundwater to assess their migration at NTS, at field scales over distances of hundreds of meters and for durations up to forty years and under hydrogeologic conditions very similar to the proposed geological repository at Yucca Mountain. The results of our study show that Tc does not necessarily exist as a mobile and conservative species TcO{sub 4}{sup -}, as has been commonly assumed. This conclusion is corroborated by recent in situ redox potential measurements, which show that groundwaters at multiple locations of the NTS are not oxidizing, and mobility of reduced Tc species (TcO{sub 2} {center_dot} nH{sub 2}O) is greatly decreased. Speciation of iodine and its associated reactivity is also complex in the groundwater at the NTS, and its effect on the mobility of iodine should be the subject of future studies.

  2. Hydrologic evaluation of the Alton reclamation-study site, Alton coal field, Utah

    USGS Publications Warehouse

    Sandberg, G.W.

    1979-01-01

    An investigation was conducted from July 1974 to September 1977 to define general hydrologic conditions at a reclamation-study site in the Alton coal field near Kanab, Utah. The average annual streamflow through the area was less than 600 acre-feet, and the water carried little sediment except during floods which result from intense local storms. Most of the surface water seeps into the ground or is diverted for irrigation downstream from the study area. Ground-water data were insufficient to define the potentiometric surface in most of the area. The water level in each of the three observation wells is above the coal layer in the immediate area of the well. A larger network of wells is needed to define the potentiometric surface throughout the area and to show its relation to surface water and the location of the coal layers. Hydrologic data should be collected continuously to establish a hydrologic base before mining begins , and data collection should be continued through the periods of mining and reclamation. (Woodard-USGS)

  3. Field Test of Limestone as a Treatment Medium for Groundwater at the Savannah River Site

    SciTech Connect

    Ekechukwu, A.A.

    2001-04-10

    Groundwater downgradient from the F- and H-Area Seepage Basins at the Savannah River Site is contaminated with acids, metals, radionuclides, and tritium originally released as part of low-level waste streams from the Radiochemical Separations Areas processing facilities. To stem the flux of tritium discharged from the basin area, a series of wells was installed to extract the groundwater and re-inject it upgradient of the seepage basins. Tritium is captured in an extraction-re-injection cycle that allows it to decay. To meet regulatory criteria for re-injection, metals and radionuclides must be treated and removed. One method under consideration for this removal is in-situ contact with limestone. Equilibration of the groundwater with limestone raises the pH to approximately 8. At this pH, metals and radionuclides can be removed by direct precipitation, co-precipitation, and enhanced adsorption. A pilot test was performed to provide data required to assess the applicability of limestone in groundwater treatment. The demonstration unit consisted of several columns of limestone with different total column lengths and thus different residence times. Ground water from the basins was passed through each of the columns and analyzed for metals, radionuclides, ions, pH, and alkalinity. The results from both the laboratory and field tests show the limestone's effectiveness as an in-situ treatment medium.

  4. Field calibrations of a low-cost aerosol sensor at a regulatory monitoring site in California

    NASA Astrophysics Data System (ADS)

    Holstius, D. M.; Pillarisetti, A.; Smith, K. R.; Seto, E.

    2014-04-01

    Health effects attributed to ambient fine particulate matter (PM2.5) now rank it among the risk factors with the highest health burdens in the world, but existing monitoring infrastructure cannot adequately characterize spatial and temporal variability in urban PM2.5 concentrations, nor in human population exposures. The development and evaluation of more portable and affordable monitoring instruments based on low-cost sensors may offer a means to supplement and extend existing infrastructure, increasing the density and coverage of empirical measurements and thereby improving exposure science and control. Here, we report on field calibrations of a custom-built, battery-operated aerosol monitoring instrument we developed using low-cost, off-the-shelf optical aerosol sensors. We calibrated our instruments using 1 h and 24 h PM2.5 data from a class III US EPA Federal Equivalent Method (FEM) PM2.5 β-attenuation monitor in continuous operation at a regulatory monitoring site in Oakland, California. We observed negligible associations with ambient humidity and temperature; linear corrections were sufficient to explain 60% of the variance in 1 h reference PM2.5 data and 72% of the variance in 24 h data. Performance at 1 h integration times was comparable to commercially available optical instruments costing considerably more. These findings warrant further exploration of the circumstances under which this class of aerosol sensors may profitably be deployed to generate improved PM2.5 data sets.

  5. Field Measurements at River and Tidal Current Sites for Hydrokinetic Energy Development: Best Practices Manual

    SciTech Connect

    Neary, Vincent S; Gunawan, Budi

    2011-09-01

    In this report, existing data collection techniques and protocols for characterizing open channel flows are reviewed and refined to further address the needs of the MHK industry. The report provides an overview of the hydrodynamics of river and tidal channels, and the working principles of modern acoustic instrumentation, including best practices in remote sensing methods that can be applied to hydrokinetic energy site characterization. Emphasis is placed upon acoustic Doppler velocimeter (ADV) and acoustic-Doppler current profiler (ADCP) instruments, as these represent the most practical and economical tools for use in the MHK industry. Incorporating the best practices as found in the literature, including the parameters to be measured, the instruments to be deployed, the instrument deployment strategy, and data post-processing techniques. The data collected from this procedure aims to inform the hydro-mechanical design of MHK systems with respect to energy generation and structural loading, as well as provide reference hydrodynamics for environmental impact studies. The standard metrics and protocols defined herein can be utilized to guide field experiments with MHK systems.

  6. Use of surfactants to improve the biological degradation of petroleum hydrocarbons in a field site study.

    PubMed

    Martienssen, M; Schirmer, M

    2007-05-01

    Mineral oil products are produced and utilized to a large extent. During the production, storage, filling up and utilization many spills occurred during the last decades. As a result, mineral oil contamination is recently one of the main problems in soil remediation. The predominant portion of the different oil components is easily degradable by microorganisms. But, its biodegradation in natural environments is often limited by the availability of the substrate to the microorganisms or by limited concentrations of nutrients and electron acceptors. Thus, the optimization of the environmental conditions can significantly improve the efficiency of degradation in both soil and groundwater (Enhanced Natural Attenuation approach). One major limiting factor in terms of the bioavailability of mineral oil is its limited solubility in water. Enhancing the solubility of the contaminants e.g. by the use of surfactants can significantly improve the efficiency of biodegradation. But, for the purpose of bioremediation only those surfactants should be used that are themselves completely biodegradable. Moreover, they have to be compatible to the surfaces of the bacteria. These requirements are met by biosurfactants and by those surfactants that contain structures comparable to naturally occurring microbial surfactants. The efficiency of such a close-to-nature surfactant (BioVersal FW) has been demonstrated for the in situ remediation of a highly contaminated site at Halle/S. (Germany). During the field scale investigation up to 50 g hydrocarbons per kg soil were eliminated over a period of 15 months.

  7. Choosing a Field: How Graduate Student Choices of Field Sites Reflect Different Ideas of "Real" Anthropology in Colombia and the United States

    ERIC Educational Resources Information Center

    Macia, Laura

    2012-01-01

    This paper examines the decisions and motivations of graduate students in cultural anthropology when defining the field sites and topics of their final projects. The decisions among students at the Universidad de los Andes in Colombia are contrasted with those at the University of Pittsburgh in the United States. A review of recent final projects…

  8. Reconnaissance of Field Sites for the Study of Chemical Weathering on the Guayana Shield, South America

    SciTech Connect

    Steefell, C I

    2003-02-01

    Despite the fact that chemical weathering of silicate rocks plays an important role in the draw-down of CO{sub 2} over geologic time scales (Berner and Berner, 1996), the overall controls on the rate of chemical weathering are still not completely understood. Lacking a mechanistic understanding of these controls, it remains difficult to evaluate a hypothesis such as that presented by Raymo and Ruddiman (1992), who suggested that enhanced weathering and CO{sub 2} draw-down resulting from the uplift of the Himalayas contributed to global cooling during the Cenozoic. At an even more fundamental level, the three to four order of magnitude discrepancy between laboratory and field weathering rates is still unresolved (White et al., 1996). There is as yet no comprehensive, mechanistic model for silicate chemical weathering that considers the coupled effects of precipitation, vadose zone flow, and chemical reactions. The absence of robust process models for silicate weathering and the failure to resolve some of these important questions may in fact be related-the controls on the overall rates of weathering cannot be understood without considering the weathering environment as one in which multiple, time-dependent chemical and physical processes are coupled (Malmstrom, 2000). Once chemical weathering is understood at a mechanistic process level, the important controls on chemical weathering (physical erosion, temperature, precipitation) can be folded into larger scale models tracking the global carbon cycle. Our goal in this study was to carry out the preliminary work needed to establish a field research site for chemical weathering om the Cuayana Shield in South America. The Guayana Shield is a Precambrian province greater than 1.5 billion years old covering portions of Venezuela, Guyana (the country), Surinam, French Guiana, and Brazil (Figure 1). More important than the age of the rocks themselves, however, is the age of the erosion surface developed on the Shield, with

  9. Borehole Completion and Conceptual Hydrogeologic Model for the IFRC Well Field, 300 Area, Hanford Site

    SciTech Connect

    Bjornstad, Bruce N.; Horner, Jacob A.; Vermeul, Vincent R.; Lanigan, David C.; Thorne, Paul D.

    2009-04-20

    A tight cluster of 35 new wells was installed over a former waste site, the South Process Pond (316-1 waste site), in the Hanford Site 300 Area in summer 2008. This report documents the details of the drilling, sampling, and well construction for the new array and presents a summary of the site hydrogeology based on the results of drilling and preliminary geophysical logging.

  10. Site 5 air sparging pilot test, Naval Air Station Cecil Field, Jacksonville, Florida.

    PubMed

    Murray, W A; Lunardini, R C; Ullo, F J; Davidson, M E

    2000-02-25

    A 72-h air sparging pilot test was conducted at Site 5 (Operable Unit 2), Naval Air Station Cecil Field, Jacksonville, FL, to determine performance parameters necessary for full-scale design. The sparge well was completed to a depth of 29 ft, several feet below the groundwater plume contaminated with volatile organic compounds (VOCs), primarily benzene, toluene, ethylbenzene, and xylenes (BTEX). Air flow rates supplied to the sparge well were 3 cubic feet/min (cfm) during the first day, 2 cfm during the second day, and 1 cfm during the third day. Water levels in monitoring wells initially rose approximately 2 ft during the first 4-5 h of the test, then receded back to pre-test equilibrium levels over the next 15 h, for a total duration of water mounding of about 20 h. A small (approximately 0.5 ft) water table drop, with subsequent recovery to equilibrium level, occurred each time the air sparging rate was decreased. Although there is considerable variation depending on direction from the sparge well, the average radius of influence varied from approximately 30 ft at 1 cfm to 50 ft at 3 cfm. The air sparge system was capable of increasing the dissolved oxygen from 0 to 6 or 7 mg/l within 12-15 h of air channels reaching a given location. A lag time of approximately 13 h was observed before air channels reached a radius of 30 ft and dissolved oxygen levels began to increase at that radius. CO(2) (stripped out of the groundwater by the sparging) decreased from a pre-test concentration of 150 to 20 mg/l at r=5 ft, and from 150 to 50 mg/l at r=30 ft, within a period of about 24 h. The rate of VOC mass removal during the pilot test was 0.06 lb/day at a sparge rate of 3 cfm, and it appears that air sparging will effect a rapid cleanup of the VOCs in the Site 5 groundwater plume.

  11. Geologic Structure at the Curiosity Field Site from Stereo Topography (Invited)

    NASA Astrophysics Data System (ADS)

    Lewis, K. W.; Edgar, L. A.; Gupta, S.; Rubin, D. M.; Kocurek, G.; Anderson, R. B.; Hayes, A. G.; Kah, L. C.

    2013-12-01

    Over the initial months of its mission, the Curiosity rover has been exploring a number of rock units exposed around its landing site within Gale crater, Mars. A major scientific focus has been the development of a stratigraphic column to understand the depositional and age relationships of diverse outcrops studied by Curiosity. Many of the outcrops encountered by the rover are stratified, and likely sedimentary in origin, enabling the determination of depositional geometries and structural tilts. Curiosity routinely acquires stereo images with its engineering (Navcam, Hazcam) and science (Mastcam, MAHLI) cameras, from which topographic data can be derived. In particular, Mastcam stereo topography can achieve several millimeter-scale resolution for near-field observations, enabling analysis of individual laminations within layered rock targets. One particularly rich target encountered by Curiosity has been the Shaler outcrop, first observed at close range on sols 120 and 121. The layered sedimentary rocks of Shaler were exposed over a distance of 30 meters along the rover traverse, with an estimated stratigraphic thickness of 1-2 meters. At this location, a number of distinct sedimentary facies are observed, including abundant cross-stratification. Strongly differential erosion highlights the varying mechanical properties of the outcrop, likely resulting from changes in grain size and degree of cementation. In general, Shaler is composed of grains of coarse-sand size and finer, differing from the much coarser fluvial conglomerates observed at the rover's landing site. Structural measurements at Shaler and nearby outcrops demonstrate a variety of bedding orientations, consistent with the observed cross-bedded architecture. Strata at Shaler in particular exhibit an overall southeastern dip of 5-15 degrees. Interpretation of this trend as a primary depositional feature suggests a largely unidirectional transport vector during formation. Alternately, the southeastern

  12. Boise Hydrogeophysical Research Site: Field-Scale Test Facility for Addressing Fundamental Questions of Environmental Science

    NASA Astrophysics Data System (ADS)

    Barrash, W.; Routh, P. S.

    2006-12-01

    The Boise Hydrogeophysical Research Site (BHRS) is a research wellfield or field-scale test facility developed in a shallow, coarse, fluvial aquifer with the objectives of supporting (a) development of cost-effective, non- invasive methods for quantitative characterization and imaging methods in heterogeneous aquifers using hydrologic and geophysical techniques; (b) examination of fundamental relationships and processes at multiple scales; (c) testing theories and models for groundwater flow and solute transport; and (d) educating and training the next generation of professionals in multidisciplinary subsurface science and engineering. The design of the wells and the wellfield provide for a wide range of single-well, cross-hole, multiwell and multilevel hydrologic, geophysical, and combined hydrologic-geophysical experiments. Efforts have been focused largely on (a) establishing the 3D distributions of geologic, hydrologic, and geophysical parameters which can then be used as the basis for testing methods to jointly invert hard and soft data to return the "known" 3D K distribution and (b) developing subsurface measurement and imaging methods including static and time-lapse tomographic imaging methods. From this work we have developed a good understanding of the hydrostratigraphic framework of the BHRS as a hierarchical system which includes layers and lenses; this framework is recognized with geologic, hydrologic, radar, seismic, and EM methods and tracer tests. Work to date has been conducted by Boise State University with some collaboration and exchange with researchers and students from other institutions. At this point the BHRS is functioning well as a field-scale control volume and test cell in a multiscale heterogeneous aquifer so there is an opportunity to increase the range of both collaborative participation and research activities at the BHRS. In this regard, opportunities exist to investigate and monitor process and property variation in time and space

  13. Field studies at the Apache Leap Research Site in support of alternative conceptual models

    SciTech Connect

    Woodhouse, E.G.; Davidson, G.R.; Theis, C.

    1997-08-01

    This is a final technical report for a project of the U.S Nuclear Regulatory Commission (sponsored contract NRC-04-090-51) with the University of Arizona. The contract was an optional extension that was initiated on July 21, 1994 and that expired on May 31, 1995. The project manager was Thomas J. Nicholson, Office of Nuclear Regulatory Research. The objectives of this contract were to examine hypotheses and conceptual models concerning unsaturated flow and transport through fractured rock, and to design and execute confirmatory field and laboratory experiments to test these hypotheses and conceptual models at the Apache Leap Research Site near Superior, Arizona. The results discussed here are products of specific tasks that address a broad spectrum of issues related to flow and transport through fractures. Each chapter in this final report summarizes research related to a specific set of objectives and can be read and interpreted as a separate entity. The tasks include detection and characterization of historical rapid fluid flow through fractured rock and the relationship to perched water systems using environmental isotopic tracers of {sup 3}H and {sup 14}C, fluid- and rock-derived {sup 2343}U/{sup 238}U measurements, and geophysical data. The water balance in a small watershed at the ALRS demonstrates the methods of acounting for ET, and estimating the quantity of water available for infiltration through fracture networks. Grain density measurements were made for core-sized samples using a newly designed gas pycnometer. The distribution and magnitude of air permeability measurements have been measured in a three-dimensional setting; the subsequent geostatistical analysis is presented. Electronic versions of the data presented here are available from authors; more detailed discussions and analyses are available in technical publications referenced herein, or soon to appear in the professional literature.

  14. Complete genome sequence of Cupriavidus basilensis 4G11, isolated from the Oak Ridge Field Research Center site

    DOE PAGES

    Ray, Jayashree; Waters, R. Jordan; Skerker, Jeffrey M.; Kuehl, Jennifer V.; Price, Morgan N.; Huang, Jiawen; Chakraborty, Romy; Arkin, Adam P.; Deutschbauer, Adam

    2015-05-14

    Cupriavidus basilensis 4G11 was isolated from groundwater at the Oak Ridge Field Research Center (FRC) site. Here, we report the complete genome sequence and annotation of Cupriavidus basilensis 4G11. The genome contains 8,421,483 bp, 7,661 predicted protein-coding genes, and a total GC content of 64.4%.

  15. CHAMPION INTERNATIONAL SUPERFUND SITE, LIBBY MONTANA FIELD PERFORMANCE EVALUATION BIOREMEDIATION UNIT: IN SITU BIOREMEDIATION OF THE UPPER AQUIFER

    EPA Science Inventory

    The field performance evaluation of the in-situ bioremediation system at Libby, Montana Superfund Site indicated that treatment appears to have occurred in the water phase under the influence of the treatment injection system. Reduced inorganic compounds may have exerted a deman...

  16. 77 FR 40637 - Wyatt VI, Inc., A Division of Wyatt Field Service Company, Working On-Site at Hovensa Oil...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-10

    ... Employment and Training Administration Wyatt VI, Inc., A Division of Wyatt Field Service Company, Working On-Site at Hovensa Oil Refinery, Christiansted, St. Croix, VI; Notice of Affirmative Determination... Adjustment Assistance (TAA) applicable to workers and former workers of Wyatt VI, Inc., a division of...

  17. Test Plan for Field Experiments to Support the Immobilized Low-Activity Waste Disposal Performance Assessment at the Hanford Site

    SciTech Connect

    Meyer, Philip D.; McGrail, B. Peter; Bacon, Diana H.

    2001-09-01

    Much of the data collected to support the Immobilized Low-Activity Waste Performance Assessment (ILAW PA) simulations have been obtained in the laboratory on a relatively small scale (less than 10 cm). In addition, the PA simulations themselves are currently the only means available to integrate the chemical and hydrologic processes involved in the transport of contaminants from the disposal facility into the environment. This report describes the test plan for field experiments to provide data on the hydraulic, transport, and geochemical characteristics of the near-field materials on a more representative (i.e., larger) scale than the laboratory data currently available. The experiments will also provide results that encompass a variety of transport processes likely to occur within the actual disposal facility. These experiments will thus provide the first integrated data on the ILAW facility performance and will provide a crucial dataset to evaluate the simulation-based estimates of overall facility performance used in the PA.

  18. Caustic-Side Solvent Extraction: Prediction of Cesium Extraction for Actual Wastes and Actual Waste Simulants

    SciTech Connect

    Delmau, L.H.; Haverlock, T.J.; Sloop, F.V., Jr.; Moyer, B.A.

    2003-02-01

    This report presents the work that followed the CSSX model development completed in FY2002. The developed cesium and potassium extraction model was based on extraction data obtained from simple aqueous media. It was tested to ensure the validity of the prediction for the cesium extraction from actual waste. Compositions of the actual tank waste were obtained from the Savannah River Site personnel and were used to prepare defined simulants and to predict cesium distribution ratios using the model. It was therefore possible to compare the cesium distribution ratios obtained from the actual waste, the simulant, and the predicted values. It was determined that the predicted values agree with the measured values for the simulants. Predicted values also agreed, with three exceptions, with measured values for the tank wastes. Discrepancies were attributed in part to the uncertainty in the cation/anion balance in the actual waste composition, but likely more so to the uncertainty in the potassium concentration in the waste, given the demonstrated large competing effect of this metal on cesium extraction. It was demonstrated that the upper limit for the potassium concentration in the feed ought to not exceed 0.05 M in order to maintain suitable cesium distribution ratios.

  19. How People Actually Use Thermostats

    SciTech Connect

    Meier, Alan; Aragon, Cecilia; Hurwitz, Becky; Mujumdar, Dhawal; Peffer, Therese; Perry, Daniel; Pritoni, Marco

    2010-08-15

    Residential thermostats have been a key element in controlling heating and cooling systems for over sixty years. However, today's modern programmable thermostats (PTs) are complicated and difficult for users to understand, leading to errors in operation and wasted energy. Four separate tests of usability were conducted in preparation for a larger study. These tests included personal interviews, an on-line survey, photographing actual thermostat settings, and measurements of ability to accomplish four tasks related to effective use of a PT. The interviews revealed that many occupants used the PT as an on-off switch and most demonstrated little knowledge of how to operate it. The on-line survey found that 89% of the respondents rarely or never used the PT to set a weekday or weekend program. The photographic survey (in low income homes) found that only 30% of the PTs were actually programmed. In the usability test, we found that we could quantify the difference in usability of two PTs as measured in time to accomplish tasks. Users accomplished the tasks in consistently shorter times with the touchscreen unit than with buttons. None of these studies are representative of the entire population of users but, together, they illustrate the importance of improving user interfaces in PTs.

  20. Treatability studies of actual listed waste sludges from the Oak Ridge Reservation (ORR)

    SciTech Connect

    Jantzen, C.M.; Peeler, D.K.; Gilliam, T.M.; Bleier, A.; Spence, R.D.

    1996-05-06

    Oak Ridge National Laboratory (ORNL) and Savannah River Technology Center (SRTC) are investigating vitrification for various low-level and mixed wastes on the Oak Ridge Reservation (ORR). Treatability studies have included surrogate waste formulations at the laboratory-, pilot-, and field-scales and actual waste testing at the laboratory- and pilot-scales. The initial waste to be processing through SRTC`s Transportable Vitrification System (TVS) is the K-1407-B and K-1407-C (B/C) Pond sludge waste which is a RCRA F-listed waste. The B/C ponds at the ORR K-25 site were used as holding and settling ponds for various waste water treatment streams. Laboratory-, pilot-, and field- scale ``proof-of-principle`` demonstrations are providing needed operating parameters for the planned field-scale demonstration with actual B/C Pond sludge waste at ORR. This report discusses the applied systems approach to optimize glass compositions for this particular waste stream through laboratory-, pilot-, and field-scale studies with surrogate and actual B/C waste. These glass compositions will maximize glass durability and waste loading while optimizing melt properties which affect melter operation, such as melt viscosity and melter refractory corrosion. Maximum waste loadings minimize storage volume of the final waste form translating into considerable cost savings.

  1. Is site-specific APEX calibration necessary for field scale BMP assessment?

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The possibility of extending parameter sets obtained at one site to sites with similar characteristics is appealing. This study was undertaken to test model performance and compare the effectiveness of best management practices (BMPs) using three parameters sets obtained from three watersheds when a...

  2. Interaction between CME and surrounding magnetic fields producing multiple flaring sites

    NASA Astrophysics Data System (ADS)

    van Driel-Gesztelyi, Lidia M.

    2015-08-01

    L. van Driel-Gesztelyi (1,2,3), D. Baker (1), T. Török (4), E. Pariat (2), L.M. Green (1),D.R. Williams (1), J. Carlyle (1,5) G. Valori (1, 2), P. Démoulin (2), B. Kliem (1,7,8),D. Long (1), S.A. Matthews (1), J.-M. Malherbe (2)(1) UCL/MSSL, UK, (2) Paris Observatory, LESIA, CNRS, France, (3) Konkoly Observatory, Hungary, (4) Predictive Science, Dan Diego, USA, (5) Max Planck Inst., Göttingen, Germany, (6) INAF, Obs. Roma, Italy, (7) Potsdam Univ., Germany, (8) Yunnan Observatories, Kunming, ChinaAnalyzing Solar Dynamics Observatory (SDO) observations of the spectacular Coronal Mass Ejection eruption on 7 June 2011, we present evidence of coronal magnetic reconnection between the expanding magnetic structure of the CME and the magnetic fields of an adjacent active region (AR). The onset of reconnection first became apparent in the SDO/AIA images when filament plasma, originally contained within the erupting flux rope, was re-directed towards remote areas in the neighboring AR, tracing the change of large-scale magnetic connectivity. The observations are presented jointly with a topological analysis of the pre-eruption magnetic configuration, and a data-constrained numerical simulation of the three-AR complex, demonstrating the formation/intensification of current sheets along a pre-existing hyperbolic flux tube (HFT) at the interface between the CME and the neighboring AR, where a secondary flare ribbon was created. Reconnection across this current sheet resulted in the formation of new magnetic connections between the erupting magnetic structure and a neighboring AR about 200 Mm from the eruption site, in strong qualitative agreement with the observations. In addition, the CME temporarily created unusually dense plasma conditions around a reconnection region at high coronal altitudes, enabling us to observe emission resulting from it. We argue that this exceptional observation of a coronal brightening was directly observable at SDO/AIA wavelengths owing to the

  3. Gas monitoring during the CO2 back production field test at the Ketzin pilot site

    NASA Astrophysics Data System (ADS)

    Szizybalski, Alexandra; Zimmer, Martin; Kujawa, Christian; Erzinger, Jörg

    2015-04-01

    The GFZ German Research Centre for Geosciences operates Europe's first on-shore CO2 storage site in Ketzin, a small town near Berlin. From June 2008 until August 2013 about 67 kt of CO2 were injected into Upper Triassic sandstones in 630 to 650 m depth. The injection phase ended with an experiment to evaluate the influence of additives on CO2 storage. During this experiment 32 t N2 and 613 t CO2 were co-injected into the borehole over a period of 25 days followed by the final injection of 66 t pure CO2. At the beginning of the experiment 10,000 l (10 Nm3) Kr were pumped into the borehole, to separate the previous pure CO2 and the CO2-N2 mixture. For the same reason, CO2 with a different isotopic composition (δ13C = -3.4±0.2o instead of δ13C = -30.6±0.4) was used for the first 548 t of the total 613 t. To demonstrate that the stored CO2 is retrievable a field test was carried out in October 2014 during a period of two weeks. Of interest, in this context, is the composition of the back-produced gas which delivers key information on possible interactions between the CO2, formation fluid and rocks. In total 240 t of gas were produced via the former injection well. The flow rates ranged between 800 and 3,200 kg gas/h. The gas was sampled after the gas/water separator and continuously analysed using a mass spectrometer, a gas chromatograph and a photoacoustic sensor, thus covering all gas components and concentrations. In addition, gas samples were collected for stable carbon isotopes investigations in the laboratory. Preliminary results show that the produced gas consists of > 97% CO2 plus mainly N2. The N2 was detected from the beginning, although the injection in 2013 ended with pure CO2. The N2 concentration decreased from about 3% to 1% during the two weeks of the experiment. In addition to these major components CH4, CO and H2 (up to 0.01%) as well as Kr and SF6 (up to 0.001%, both were used as tracers in 2013) were detected. The gas composition of natural

  4. Linking physics with physiology in TMS: a sphere field model to determine the cortical stimulation site in TMS.

    PubMed

    Thielscher, Axel; Kammer, Thomas

    2002-11-01

    A fundamental problem of transcranial magnetic stimulation (TMS) is determining the site and size of the stimulated cortical area. In the motor system, the most common procedure for this is motor mapping. The obtained two-dimensional distribution of coil positions with associated muscle responses is used to calculate a center of gravity on the skull. However, even in motor mapping the exact stimulation site on the cortex is not known and only rough estimates of its size are possible. We report a new method which combines physiological measurements with a physical model used to predict the electric field induced by the TMS coil. In four subjects motor responses in a small hand muscle were mapped with 9-13 stimulation sites at the head perpendicular to the central sulcus in order to keep the induced current direction constant in a given cortical region of interest. Input-output functions from these head locations were used to determine stimulator intensities that elicit half-maximal muscle responses. Based on these stimulator intensities the field distribution on the individual cortical surface was calculated as rendered from anatomical MR data. The region on the cortical surface in which the different stimulation sites produced the same electric field strength (minimal variance, 4.2 +/- 0.8%.) was determined as the most likely stimulation site on the cortex. In all subjects, it was located at the lateral part of the hand knob in the motor cortex. Comparisons of model calculations with the solutions obtained in this manner reveal that the stimulated cortex area innervating the target muscle is substantially smaller than the size of the electric field induced by the coil. Our results help to resolve fundamental questions raised by motor mapping studies as well as motor threshold measurements.

  5. PISCES field chemical emissions monitoring project: Site 102 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 102. Site 102 is a cyclone boiler burning a sub-bituminous coal. Site 102 employs an electrostatic precipitator for particulate control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  6. Direct optical mapping of transcription factor binding sites on field-stretched λ-DNA in nanofluidic devices

    PubMed Central

    Sriram, K. K.; Yeh, Jia-Wei; Lin, Yii-Lih; Chang, Yi-Ren; Chou, Chia-Fu

    2014-01-01

    Mapping transcription factor (TF) binding sites along a DNA backbone is crucial in understanding the regulatory circuits that control cellular processes. Here, we deployed a method adopting bioconjugation, nanofluidic confinement and fluorescence single molecule imaging for direct mapping of TF (RNA polymerase) binding sites on field-stretched single DNA molecules. Using this method, we have mapped out five of the TF binding sites of E. coli RNA polymerase to bacteriophage λ-DNA, where two promoter sites and three pseudo-promoter sites are identified with the corresponding binding frequency of 45% and 30%, respectively. Our method is quick, robust and capable of resolving protein-binding locations with high accuracy (∼ 300 bp), making our system a complementary platform to the methods currently practiced. It is advantageous in parallel analysis and less prone to false positive results over other single molecule mapping techniques such as optical tweezers, atomic force microscopy and molecular combing, and could potentially be extended to general mapping of protein–DNA interaction sites. PMID:24753422

  7. Hydrologic Instrumentation of Field Sites to Understand Short Term Changes in Water Quality

    NASA Astrophysics Data System (ADS)

    Iqbal, M. Z.; Clayton, M.

    2011-12-01

    This project is funded by a successful NSF-CCLI grant currently in effect. The objective of this project is to build a real time water quality monitoring facility by the Dry Run Creek on the University of Northern Iowa campus. The long term goal is to turn this site into a model outdoor educational resource for students to study the critical elements of the hydrologic environment. Weekly class sessions otherwise make it difficult for students to deal with the daily changes is water chemistry. Upon completion of the project, students will be able to look at the diurnal variations in the water quality through a website available for public viewing. Besides, they will have the opportunity to participate in a variety of research and learning activities directly at the site. Four (4) pieces of instruments are in the process of being installed at the experimental site. The instruments are 1) YSI 6600 V2 extended deployment probe to measure water quality parameters in the Dry Run Creek (i.e., pH, Total Dissolved Solids, conductivity, Dissolved Oxygen, temperature, turbidity, chlorophyll, etc.); 2) OTT RLS Radar to measure water level fluctuations in the creek; 3) Hydrolab MS5 mini-sonde to continuously measure pH, TDS, conductivity, DO, temperature, turbidity, and nitrate in a 70 ft deep ground water well on the site; and 4) DL 3000 data logger to receive all data from the above 3 pieces of equipment and automatically upload them to a website. Site preparation, including digging trenches for data cable and electric wires has been completed. Instrumental calibration is in progress and the site is expected to be up and running soon. We expect that this well site expansion plan will considerably strengthen our hydrology curriculum and facilitate more effective dissemination of the project outcome.

  8. Career Field Experience: A Look at On-site Usage by High School Communication Class.

    ERIC Educational Resources Information Center

    Kaye, Thomas

    The career field experience program at a midwestern high school places broadcasting students on location for observation of the profession and optional job training or work. In addition to radio and television stations, field locations include advertising agencies with production studios, corporate production facilities, recording studios, cable…

  9. Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington

    NASA Technical Reports Server (NTRS)

    Golombek, M. P. (Editor); Edgett, K. S. (Editor); Rice, J. W. , Jr. (Editor)

    1995-01-01

    Mars Pathfinder will place a single lander on the surface of Mars on July 4, 1997, following a December 1996 launch. As a result of the very successful first Mars Pathfinder Landing Site Workshop, the project has selected the Ares Vallis outflow channel in Chryse Planitia as the landing site. This location is where a large catastrophic outflow channel debouches into the northern lowlands. A second workshop and series of field trips, entitled Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington, were held in Spokane and Moses Lake, Washington. The purpose of the workshop was to provide a focus for learning as much as possible about the Ares Vallis region on Mars before landing there. The rationale is that the more that can be learned about the general area prior to landing, the better scientists will be able interpret the observations made by the lander and rover and place them in the proper geologic context. The field trip included overflights and surface investigations of the Channeled Scabland (an Earth analog for the martian catastrophic outflow channels), focusing on areas particularly analogous to Ares Vallis and the landing site. The overflights were essential for placing the enormous erosional and depositional features of the Channeled Scabland into proper three-dimensional context. The field trips were a joint educational outreach activity involving K-12 science educators, Mars Pathfinder scientists and engineers, and interested scientists from the Mars scientific community. Part 1 of the technical report on this workshop includes a description of the Mars Pathfinder mission, abstracts accepted for presentation at the workshop, an introduction to the Channeled Scabland, and field trip guides for the overflight and two field trips. This part, Part 2, includes the program for the workshop, summaries of the workshop technical sessions, a summary of the field trips and ensuing

  10. Mars Pathfinder Landing Site Workshop II: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington

    NASA Astrophysics Data System (ADS)

    Golombek, M. P.; Edgett, K. S.; Rice, J. W., Jr.

    1995-09-01

    Mars Pathfinder will place a single lander on the surface of Mars on July 4, 1997, following a December 1996 launch. As a result of the very successful first Mars Pathfinder Landing Site Workshop, the project has selected the Ares Vallis outflow channel in Chryse Planitia as the landing site. This location is where a large catastrophic outflow channel debouches into the northern lowlands. A second workshop and series of field trips, entitled Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington, were held in Spokane and Moses Lake, Washington. The purpose of the workshop was to provide a focus for learning as much as possible about the Ares Vallis region on Mars before landing there. The rationale is that the more that can be learned about the general area prior to landing, the better scientists will be able interpret the observations made by the lander and rover and place them in the proper geologic context. The field trip included overflights and surface investigations of the Channeled Scabland (an Earth analog for the martian catastrophic outflow channels), focusing on areas particularly analogous to Ares Vallis and the landing site. The overflights were essential for placing the enormous erosional and depositional features of the Channeled Scabland into proper three-dimensional context. The field trips were a joint educational outreach activity involving K-12 science educators, Mars Pathfinder scientists and engineers, and interested scientists from the Mars scientific community. Part 1 of the technical report on this workshop includes a description of the Mars Pathfinder mission, abstracts accepted for presentation at the workshop, an introduction to the Channeled Scabland, and field trip guides for the overflight and two field trips. This part, Part 2, includes the program for the workshop, summaries of the workshop technical sessions, a summary of the field trips and ensuing

  11. Petrographic-geochemical characteristics of granitoids and their epigenetic alteration products in paleovalley fields (Vitim uranium-ore site)

    NASA Astrophysics Data System (ADS)

    Kuznetsova, E. S.; Domarenko, V. A.; Matveenko, I. A.

    2016-09-01

    The study describes the results of the mineral and element composition of granitoids in basement and weathering crust of Khiagdinsk ore field in Vitim uranium ore site. It has been stated that granitoids in basement consist of leucocratic biotite granite of subalkaline group. The major rock-forming, accessory (apatite, zircon, sphene (titanite), magnetite, monazite, xenotime), and uranium-bearing minerals have been determined. Weathering crust is composed of unlithified or weakly lithified sediments, among which sandy and sandy medium gravel deposits have been distinguished in terms of mineralogical and granulometric texture. High radioactivity of granitoids was revealed in thorium-uranium basement and natural uranium. The combination of the specified factors presupposes that granitoids of Vitim uranium ore site may be a source of uranium in the fields of the paleovalley type.

  12. Spatial distributions and chemical properties of PM2.5 based on 21 field campaigns at 17 sites in China.

    PubMed

    Zheng, Jing; Hu, Min; Peng, Jianfei; Wu, Zhijun; Kumar, Prashant; Li, Mengren; Wang, Yujue; Guo, Song

    2016-09-01

    Severe air pollution and its associated health impacts have become one of the major concerns in China. A detailed analysis of PM2.5 chemical compositions is critical for optimizing pollution control measures. In this study, daily 24-h bulk filter samples were collected and analyzed for totally 21 field campaigns at 17 sites in China between 2008 and 2013. The 17 sites were classified into four groups including six urban sites, seven regional sites, two coastal sites in four fast developing regions of China (i.e. Beijing-Tianjin-Hebei region, Yangtze River Delta, Pearl River Delta and Sichuan Basin), and two ship cruise measurements covered the East China Sea and Yellow Sea of China. The high average concentrations of PM2.5 and the occurrences of extreme cases at most sites imply the widespread air pollution in China. Fine particles were largely composed of organic matter and secondary inorganic species at most sites. High correlation between the temporal trends of PM2.5 and secondary species of urban and regional sites highlights the uniformly distributed air pollutants within one region. Secondary inorganic species were the dominant contributors to the high PM2.5 concentration in Northern China. However in Southern China, the relative contributions of different chemical species kept constant as PM2.5 increased. This study provides us a better understanding of the current state of air pollution in diversified Chinese cities. Analysis of chemical signatures of PM2.5 could be a strong support for model validation and emission control strategy. PMID:27341151

  13. ELF (Extremely Low Frequency) communications system ecological monitoring program: Measurements of ELF electromagnetic fields for site selection and Characterization-1984

    NASA Astrophysics Data System (ADS)

    Gauger, J. R.; Brosh, R. M.; Zapotosky, J. E.

    1985-06-01

    A long-term program for studying possible effects from the operation of the Navy's ELF Communications System is being conducted on biota and ecosystems components in north-western Wisconsin and the Upper Peninsula of Michigan. Sixteen general types of organisms from three major ecosystems in the ELF system area are being examined. Formulation of an ELF Ecological Monitoring Program was completed in early 1982 by the Department of the Navy. Monitoring studies were conducted through a peer-reviewed, competitive bidding process in mid-1982, and studies were initiated in late summer of the same year. Beginning in 1983 and continuing during 1984 major activities of the program consisted of characterization of critical aspects of each study, collection of data to validate assumptions made in proposals, and selection of study sites. Measurements of electromagnetic fields at the investigator-selected sites are documented, and the acceptability and status of the sites in light of the electromagnetic exposure criteria are discussed.

  14. ELF (Extremely Low Frequency) communications system ecological monitoring program: Measurements of ELF electromagnetic fields for site selection and characterization, 1983

    NASA Astrophysics Data System (ADS)

    Enk, J. O.; Gauger, J. R.

    1985-01-01

    A long-term program for studying possible effects from the operation of the Navy's ELF Communications System is being conducted on biota and ecosystems components in northwestern Wisconsin and the Upper Peninsula of Michigan. Sixteen general types of organisms from three major ecosystems in ELF system areas are being examined. Formulation of an ELF Ecological Monitoring Program was completed in early 1982 by the Department of the Navy. Monitoring studies were conducted through a peer-reviewed, competitive bidding process in mid-1982, and studies were initiated in late summer. Major activities of the program during 1983 consisted of characterization of critical aspects of each study, collection of data to validate assumption made in proposals, and selection of study sites. Measurements of electromagnetic fields at the investigator-selected sites are documented, and the acceptability and status of the sites in light of the electromagnetic exposure criteria are discussed.

  15. Natural bioventing remediation from tidal wave action at a field site

    SciTech Connect

    Kampbell, D.H.; Hansen, J.E.; Kittel, J.A.

    1996-12-31

    A remediation research study has been implemented at a jet fuel spill site on an island airport. A buried pipeline fracture several years ago resulted in a fuel spill exceeding 160,000 gallons. The site hydrogeology is a fragmented coral matrix with fresh water overlying more dense salt water. Water table fluctuations of about two feet occur once every twelve hours from tidal action. The research approach being pursued is to recover free-phase floating petroleum liquid using vacuum-mediated subsurface skimming wells. The vacuum will create an active vadose zone aeration to enhance aerobic biodegradation processes and vaporization of fuel. Once the floating fuel is removed, a natural bioventing action caused by tidal oscillations will complete remediation of the spill site.

  16. A network of field test sites as a platform for research on engineering and management of the highway transportation infrastructure

    NASA Astrophysics Data System (ADS)

    Aktan, A. Emin; Frangopol, Dan M.; Ghasemi, Hamid; Shenton, Harry W.; Shinozuka, Masanobu; Madanat, Samar

    2004-07-01

    An effort is currently underway to create an Engineering Research Consortium Initiative (ERCI) focused on engineering and management of the highway transportation infrastructure. The goal of the ERCI will be to provide administrative and logistical support for a coordinated, problem-focused research program on the highway transportation infrastructure system. The cornerstone of the initiative will be field test-sites. Example sites might include major long span bridges, sample populations of operating bridges, decommissioned bridges, a regional network of highways and bridges, various types of pavement and geotechnical structures, or a major transportation hub serving a metropolitan area. Sites would be instrumented to collect a broad range of engineering (structural, geotechnical, hydraulic), human (traffic) and natural (climatological, seismological) response data. The field sites would be networked to provide real-time access to test facilities across the country; a secure central repository would be established for collecting data from the sites. The data and information gathered from these sites would be used by engineers and scientists to study the complex interactions and cause-and-effect relations of the various engineered, human and natural components of the highway hyper-system. A major research thrust of the ERCI will be security of the highway infrastructure system, with particular emphasis on bridges. The National Science Foundation and the Federal Highway Administration are expected to provide funding for the program through a joint agency initiative. Two workshops were recently held with experts from around the world to discuss the plans for the ERCI. The paper provides more details on the ERCI and the status of the effort to date.

  17. Luminescence spectroscopy of matrix-isolated atomic manganese: site size and orbital occupancy dependence of crystal field splitting.

    PubMed

    Collier, Martin A; Byrne, Owen; Murray, Ciaran; McCaffrey, John G

    2010-04-28

    Narrow linewidth emission features observed in the near-UV following y (6)P state excitation of atomic manganese isolated in the solid rare gases are assigned to b (4)D and a (4)P states. These states arise from the 3d(5)4s(2) electronic configuration, identical to that of the (6)S ground state, and the origin of the narrow linewidths. Two thermally stable sites, labeled blue and red on the basis of their position in absorption spectra, are occupied by atomic Mn in Ar and Kr while a single site is present in Xe. The red site produces a single, narrow line emission for the b (4)D state at 329 nm. In contrast, a lineshape analysis of the complex blue site b (4)D state emission between 331 and 332 nm reveals the occurrence of three zero phonon lines (ZPLs). Millisecond emission decay curves recorded for these features are found to be complex, requiring double and triple exponential fit functions. The origins of the complex decays and multiple ZPLs are shown to arise from weak crystal field splitting (CFS) of the J=7/2 spin-orbit level of the b (4)D state of atomic Mn isolated in the blue site of the solid rare gases. Fields of cubic symmetry are capable of inducing splitting for J>3/2 so atoms isolated in both single vacancy and tetravacancy sites in the fcc lattices of the solid rare gases are prone to this effect. b (4)D state emission is also produced following y (6)P excitation for Mn atoms occupying the red sites in Ar and Kr. However, Mn atoms isolated in the larger tetravacancy sites have small matrix shifts and do not exhibit any CFS. The magnitudes of the weak CF splittings are shown to depend on both the excited state electronic configurations 3d(5)4s(2) b (4)D and 3d(6)4s(1) a (4)D states and the size of the matrix site occupied by atomic Mn.

  18. Natural horizontal transfer of a naphthalene dioxygenase gene between bacteria native to a coal tar-contaminated field site.

    PubMed Central

    Herrick, J B; Stuart-Keil, K G; Ghiorse, W C; Madsen, E L

    1997-01-01

    Horizontal transfer of genes responsible for pollutant biodegradation may play a key role in the evolution of bacterial populations and the adaptation of microbial communities to environmental contaminants. However, field evidence for horizontal gene transfer between microorganisms has traditionally been very difficult to obtain. In this study, the sequences of the 16S rRNA and naphthalene dioxygenase iron-sulfur protein (nahAc) genes of nine naphthalene-degrading bacteria isolated from a coal tar waste-contaminated site, as well as a naphthalene-degrading bacterium from a contaminated site in Washington state and two archetypal naphthalene-degrading strains, were compared. Seven strains from the study site had a single nahAc allele, whereas the 16S rRNA gene sequences of the strains differed by as much as 7.9%. No nahAc alleles from the site were identical to those of the archetypal strains, although the predominant allele was closely related to that of Pseudomonas putida NCIB 9816-4, isolated in the British Isles. However, one site-derived nahAc allele was identical to that of the Washington state strain. Lack of phylogenetic congruence of the nahAc and 16S rRNA genes indicates that relatively recent in situ horizontal transfer of the nahAc gene has occurred, possibly as a direct or indirect consequence of pollutant contamination. Alkaline lysis plasmid preparations and pulsed-field gel electrophoresis have revealed the presence of plasmids ranging in size from 70 to 88 kb in all site isolates. Southern hybridizations with a 407-bp nahAc probe have suggested that the nahAc gene is plasmid borne in all the site isolates but one, a strain isolated from subsurface sediment 400 m upstream from the source of the other site isolates. In this strain and in the naphthalene-degrading strain from Washington state, nahAc appears to be chromosomally located. In addition, one site isolate may carry nahAc on both chromosome and plasmid. Within the group of bacteria with

  19. Application of an Optimal Search Strategy for the DNAPL Source Identification to a Field Site in Nanjing, China

    NASA Astrophysics Data System (ADS)

    Longting, M.; Ye, S.; Wu, J.

    2014-12-01

    Identification and removing the DNAPL source in aquifer system is vital in rendering remediation successful and lowering the remediation time and cost. Our work is to apply an optimal search strategy introduced by Zoi and Pinder[1], with some modifications, to a field site in Nanjing City, China to define the strength, and location of DNAPL sources using the least samples. The overall strategy uses Monte Carlo stochastic groundwater flow and transport modeling, incorporates existing sampling data into the search strategy, and determines optimal sampling locations that are selected according to the reduction in overall uncertainty of the field and the proximity to the source locations. After a sample is taken, the plume is updated using a Kalman filter. The updated plume is then compared to the concentration fields that emanate from each individual potential source using fuzzy set technique. The comparison followed provides weights that reflect the degree of truth regarding the location of the source. The above steps are repeated until the optimal source characteristics are determined. Considering our site case, some specific modifications and work have been done as follows. K random fields are generated after fitting the measurement K data to the variogram model. The locations of potential sources that are given initial weights are targeted based on the field survey, with multiple potential source locations around the workshops and wastewater basin. Considering the short history (1999-2010) of manufacturing optical brightener PF at the site, and the existing sampling data, a preliminary source strength is then estimated, which will be optimized by simplex method or GA later. The whole algorithm then will guide us for optimal sampling and update as the investigation proceeds, until the weights finally stabilized. Reference [1] Dokou Zoi, and George F. Pinder. "Optimal search strategy for the definition of a DNAPL source." Journal of Hydrology 376.3 (2009): 542

  20. INTRINSIC BIOREMEDIATION OF FUEL CONTAMINATION IN GROUND WATER AT A FIELD SITE

    EPA Science Inventory

    A spill of gasoline occurred at an automobile service station in 1986. Oily phase residue in the subsurface has continued for the past 8 yr to release water soluble fuel hydrocarbons into the aquifer. The site was characterized for implementation of intrinsic remediation. The sub...

  1. FIELD SCALE EVALUATION OF TREATMENT OF TCE IN A BIOWALL AT THE OU-1 SITE

    EPA Science Inventory

    A passive reactive barrier (Biowall) was installed at the OU-1 site at Altus Air Force Base, Oklahoma to treat TCE contamination in ground water from a landfill. Depth to ground water varies from 1.8 to 2.4 meters below land surface. To intercept and treat the plume of contamin...

  2. Changes in Contaminant Mass Discharge from DNAPL Source Mass Depletion: Evaluation at Two Field Sites

    EPA Science Inventory

    Changes in contaminant fluxes resulting from aggressive remediation of dense nonaqueous phase liquid (DNAPL) source zone were investigated at two sites, one at Hill Air Force Base (AFB), Utah, and the other at Ft. Lewis Military Reservation, WA. Passive Flux Meters (PFM) and a va...

  3. Technical procedures for land use, Deaf Smith County site, Texas: Environmental Field Program: Final draft

    SciTech Connect

    Not Available

    1987-09-01

    This volume contains Technical Procedures pursuant to the Land Use Site Study Plan including land use data acquisition, land use/land cover map compilation, verification of land use/land cover map accuracy, and land use/land cover data analysis. 22 refs., 5 figs.

  4. Field trials of Growmate humic products in Central and South America: benefits of networked sites.

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effectiveness of humic products as crop and soil amendments deserves further study but remains in dispute. Broad-based evidence for their performance could be gained through coordinated networks of sites that evaluate humic products under diverse soil and weather conditions and for several crop...

  5. An estimate of field size distributions for selected sites in the major grain producing countries

    NASA Technical Reports Server (NTRS)

    Podwysocki, M. H.

    1977-01-01

    The field size distributions for the major grain producing countries of the World were estimated. LANDSAT-1 and 2 images were evaluated for two areas each in the United States, People's Republic of China, and the USSR. One scene each was evaluated for France, Canada, and India. Grid sampling was done for representative sub-samples of each image, measuring the long and short axes of each field; area was then calculated. Each of the resulting data sets was computer analyzed for their frequency distributions. Nearly all frequency distributions were highly peaked and skewed (shifted) towards small values, approaching that of either a Poisson or log-normal distribution. The data were normalized by a log transformation, creating a Gaussian distribution which has moments readily interpretable and useful for estimating the total population of fields. Resultant predictors of the field size estimates are discussed.

  6. Source of the Australasian tektite strewn field - A possible off-shore impact site

    NASA Technical Reports Server (NTRS)

    Schnetzler, C. C.; Walter, L. S.; Marsh, J. G.

    1988-01-01

    Although there is a preponderance of evidence that tektites were formed by asteroid impacts on the earth, no source crater has been found for the largest and youngest of the strewn fields - the Austalasian strewn field. A combined Seasat/Geos 3 altimeter data set of sea surface heights in the northern portion of the Australasian strewn field has been examined for negative gravity anomalies on the continental shelf and slope which might be related to the source crater for these tektites. A large negative anomaly called the Qui Nhon Slope Anomaly is a sea surface depression of approximately 1.5 meters over an area of 100 km diameter. It corresponds to a gravity anomaly of about -50 mgal. It is proposed that this anomaly may be due to the impact structure that produced the Australasian strewn field.

  7. Field and laboratory results for the evaluation of metal contaminants at a Superfund site

    SciTech Connect

    Callahan, C.A.; Svirsky, S.; Bollman, M.

    1994-12-31

    Measurements were made for seed germination plant uptake, laboratory biomass (lettuce, Lactuca saliva), mortality and bioaccumulation tests (earthworm, Eisenia fetida) in the field and laboratory, field and laboratory uptake with small mammals and laboratory uptake with Xenopus. Metals included cadmium, arsenic, chromium, copper, lead, nickel, and zinc collected in soils at five stations and a reference station, and in earthworm tissue, gut contents, in plants, small mammals and frogs exposed in the laboratory. These measurement endpoints were selected to assess the potential risks of the metal plating wastes to avian, mammalian, and wetland assessment endpoints in support of ecological risk assessment. Mortality was observed in the field earthworm test after a 7 day exposure. No inhibition of 4 day seed germination was observed at any station in field or greenhouse studies, however 28 day biomass tests for lettuce resulted in significant reductions in biomass. Cadmium measured in earthworm tissue was considerably greater for indigenous earthworms compared to laboratory exposed earthworms for 28 days, or to earthworms exposed in the field for 26 days. Differences in the results obtained from field and laboratory exposures for bioaccumulation of metals demonstrates the importance of infield exposure in studies to support ecological risk assessment.

  8. Field-based ET calibration and validation sites in interior Alaska: Preparatory Science for NASA's planned HyspIRI Mission

    NASA Astrophysics Data System (ADS)

    Prakash, A.; Cristobal, J.; Fochesatto, G. J.; Starkenburg, D. P.; Kane, D. L.; Gens, R.; Alfieri, J. G.; Irving, K.; Anderson, M. C.; Kustas, W.

    2012-12-01

    Evapotranspiration (ET) is a critical component of the hydrologic cycle in interior Alaska, being about 74% of summer precipitation or 50% of annual precipitation, and is a process that will become more important as we witness increasing trends of climate warming, permafrost degradation, forest fire occurrences, and significant land cover changes. In preparation for NASA's planned Hyperspectral Infrared Imager (HyspIRI) satellite mission; we have established two experimental sites in interior Alaska to measure representative ET values for typical boreal forest in this region as a basis to estimate and upscale ET from remote sensing solar and thermal data. The first site (University of Alaska Fairbanks, UAF, north campus) is located in a needleleaf forest mainly composed of black spruce (Picea mariana) and the second site (Caribou-Poker Creek Research Watershed) is in a deciduous forest mainly composed of paper birch (Betula papyrifera). Both field sites are equipped with sonic anemometers and gas analyzers at 24 m height operating at a 20Hz sampling rate, and, additionally, the UAF north campus site includes a 3 and 12m sonic anemometers. At 24m, the tower is also equipped with a four component net radiometer sensor and air temperature and pressure sensors are installed at different heights. To monitor ground heat, temperature and soil moisture sensors as well as heat flux plates have also been installed in the organic and the subsurface soil layers. Additionally, a Large Aperture Scintillometer (LAS) transmitter and receiver units with a separation of 1.2 km have been installed across the tower ensuring a beam height of 24m. Data is recorded on data loggers and downloaded for quality check and processing on a weekly basis. Further details of tower set-up are available at www.et.alaska.edu. Data from the field instruments are presented and their use for Alaska specific ET model calibration are discussed. The field set-up provides all input data for ET modeling and

  9. Fate and Transport of Bacteriophage (MS2 and PRD1) During Field-Scale Infiltration at a Research Site in Los Angeles County, CA

    NASA Astrophysics Data System (ADS)

    Anders, R.; Chrysikopoulos, C. V.

    2003-12-01

    As the use of tertiary-treated municipal wastewater (recycled water) for replenishment purposes continues to increase, provisions are being established to protect ground-water resources by ensuring that adequate soil-retention time and distance requirements are met for pathogen removal. However, many of the factors controlling virus fate and transport (e.g. hydraulic conditions, ground-water chemistry, and sediment mineralogy) are interrelated and poorly understood. Therefore, conducting field-scale experiments using surrogates for human enteric viruses at an actual recharge basin that uses recycled water may represent the best approach for establishing adequate setback requirements. Three field-scale infiltration experiments were conducted at such a basin using bacterial viruses (bacteriophage) MS2 and PRD1 as surrogates for human viruses, bromide as a conservative tracer, and recycled water. The specific research site consists of a test basin constructed adjacent to a large recharge facility (spreading grounds) located in the Montebello Forebay of Los Angeles County, California. The soil beneath the test basin is predominantly medium to coarse, moderately sorted, grayish-brown sand. The first experiment was conducted over a 2-day period to determine the feasibility of conducting field-scale infiltration experiments using recycled water seeded with high concentrations of bacteriophage and bromide as tracers. Based on the results of the first experiment, a second experiment was completed when similar hydraulic conditions existed at the test basin. The third infiltration experiment was conducted to confirm the results obtained from the second experiment. Data were obtained for samples collected during the second and third field-scale infiltration experiments from the test basin itself and from depths of 0.3, 0.6, 1.0, 1.5, 3.0, and 7.6 m below the bottom of the test basin. These field-scale tracer experiments indicate bacteriophage are attenuated by removal and (or

  10. Virus fate and transport during recharge using recycled water at a research field site in the Montebello Forebay, Los Angeles County, California, 1997-2000

    USGS Publications Warehouse

    Anders, Robert; Yanko, William A.; Schroeder, Roy A.; Jackson, James L.

    2004-01-01

    Total and fecal coliform bacteria distributions in subsurface water samples collected at a research field site in Los Angeles County were found to increase from nondetectable levels immediately before artificial recharge using tertiary-treated municipal wastewater (recycled water). This rapid increase indicates that bacteria can move through the soil with the percolating recycled water over intervals of a few days and vertical and horizontal distances of about 3 meters. This conclusion formed the basis for three field-scale experiments using bacterial viruses (bacteriophage) MS2 and PRD1 as surrogates for human enteric viruses and bromide as a conservative tracer to determine the fate and transport of viruses in recycled water during subsurface transport under actual recharge conditions. The research field site consists of a test basin constructed adjacent to a large recharge facility (spreading grounds) located in the Montebello Forebay of Los Angeles County, California. The soil beneath the test basin is predominantly medium to coarse, moderately sorted, grayish-brown sand. The three tracer experiments were conducted during August 1997, August-September 1998, and August 2000. For each experiment, prepared solutions of bacteriophage and bromide were sprayed on the surface of the water in the test basin and injected, using peristaltic pumps, directly into the feed pipe delivering the recycled water to the test basin. Extensive data were obtained for water samples collected from the test basin itself and from depths of 0.3, 0.6, 1.0, 1.5, 3.0, and 7.6 meters below the bottom of the test basin. The rate of bacteriophage inactivation in the recycled water, independent of any processes occurring in the subsurface, was determined from measurements on water samples from the test basin. Regression analysis of the ratios of bacteriophage to bromide was used to determine the attenuation rates for MS2 and PRD1, defined as the logarithmic reduction in the ratio during each

  11. Actualities and Perspectives in Neurosurgery

    PubMed Central

    Iencean, SM; Brehar, FM

    2008-01-01

    In the field of neurosurgery, like in other surgical specialties, the last decades have brought major achievements. The series of revolutionary discoveries has started during the last century in the fifties, with stereotactic radiosurgery, then continued with the implementation of operative microscope (during the seventies), the endovascular embolisation in the nineties and finally with the major improvement in robotic neurosurgery and molecular neurosurgery at the beginning of this century. The major innovation has been brought not only in the field of therapeutical measures but also in the field of neuro– imaging. Thus, the modern MRI with more than 3 Tesla, can reveal to the neurosurgeon the most intimate structures of the nervous system. Several important areas in neurosurgery like: vascular neurosurgery, functional neurosurgery and brain tumors pathology, benefit from the modern technology and from the latest discoveries from genetic and molecular biology. In conclusion, summarizing the discoveries of the last decade, we emphasize that the related areas like genetics, molecular biology, computer technology become more and more important in the future progress of the neurosurgery. PMID:20108475

  12. Modeling of CBM production, CO2 injection, and tracer movement at a field CO2 sequestration site

    SciTech Connect

    Siriwardane, Hema J.; Bowes, Benjamin D.; Bromhal, Grant S.; Gondle, Raj K.; Wells, Arthur W.; Strazisar, Brian R.

    2012-07-01

    Sequestration of carbon dioxide in unmineable coal seams is a potential technology mainly because of the potential for simultaneous enhanced coalbed methane production (ECBM). Several pilot tests have been performed around the globe leading to mixed results. Numerous modeling efforts have been carried out successfully to model methane production and carbon dioxide (CO{sub 2}) injection. Sensitivity analyses and history matching along with several optimization tools were used to estimate reservoir properties and to investigate reservoir performance. Geological and geophysical techniques have also been used to characterize field sequestration sites and to inspect reservoir heterogeneity. The fate and movement of injected CO{sub 2} can be determined by using several monitoring techniques. Monitoring of perfluorocarbon (PFC) tracers is one of these monitoring technologies. As a part of this monitoring technique, a small fraction of a traceable fluid is added to the injection wellhead along with the CO{sub 2} stream at different times to monitor the timing and location of the breakthrough in nearby monitoring wells or offset production wells. A reservoir modeling study was performed to simulate a pilot sequestration site located in the San Juan coal basin of northern New Mexico. Several unknown reservoir properties at the field site were estimated by modeling the coal seam as a dual porosity formation and by history matching the methane production and CO{sub 2} injection. In addition to reservoir modeling of methane production and CO{sub 2} injection, tracer injection was modeled. Tracers serve as a surrogate for determining potential leakage of CO{sub 2}. The tracer was modeled as a non-reactive gas and was injected into the reservoir as a mixture along with CO{sub 2}. Geologic and geometric details of the field site, numerical modeling details of methane production, CO{sub 2} injection, and tracer injection are presented in this paper. Moreover, the numerical

  13. Soil-water movement under natural-site and waste-site conditions: A multiple-year field study in the Mojave Desert, Nevada

    USGS Publications Warehouse

    Andraski, B.J.

    1997-01-01

    flow at the field sites. Below the depth of temporal water content change, the estimated liquid fluxes ranged from 10-10 to 10-15 cm/s, isothermal vapor fluxes ranged from 10-10 to 10-13 cm/s, and the nonisothermal vapor fluxes ranged from 10-8 to 10-10 cm/s.

  14. Direct observation and mechanism for enhanced field emission sites in platinum ion implanted/post-annealed ultrananocrystalline diamond films

    SciTech Connect

    Panda, Kalpataru E-mail: phy.kalpa@gmail.com; Inami, Eiichi; Sugimoto, Yoshiaki; Sankaran, Kamatchi J.; Tai, Nyan Hwa; Lin, I-Nan

    2014-10-20

    Enhanced electron field emission (EFE) properties for ultrananocrystalline diamond (UNCD) films upon platinum (Pt) ion implantation and subsequent post-annealing processes is reported, viz., low turn-on field of 4.17 V/μm with high EFE current density of 5.08 mA/cm{sup 2} at an applied field of 7.0 V/μm. Current imaging tunneling spectroscopy (CITS) mode in scanning tunneling spectroscopy directly revealed the increased electron emission sites density for Pt ion implanted/post-annealed UNCD films than the pristine one. The high resolution CITS mapping and local current–voltage characteristic curves demonstrated that the electrons are dominantly emitted from the diamond grain boundaries and Pt nanoparticles.

  15. BIOPHYSICS. Response to Comments on "Extreme electric fields power catalysis in the active site of ketosteroid isomerase".

    PubMed

    Fried, Stephen D; Boxer, Steven G

    2015-08-28

    Natarajan et al. and Chen and Savidge comment that comparing the electric field in ketosteroid isomerase's (KSI's) active site to zero overestimates the catalytic effect of KSI's electric field because the reference reaction occurs in water, which itself exerts a sizable electrostatic field. To compensate, Natarajan et al. argue that additional catalytic weight arises from positioning of the general base, whereas Chen and Savidge propose a separate contribution from desolvation of the general base. We note that the former claim is not well supported by published results, and the latter claim is intriguing but lacks experimental basis. We also take the opportunity to clarify some of the more conceptually subtle aspects of electrostatic catalysis.

  16. Field site leaching from recycled concrete aggregates applied as sub-base material in road construction.

    PubMed

    Engelsen, Christian J; Wibetoe, Grethe; van der Sloot, Hans A; Lund, Walter; Petkovic, Gordana

    2012-06-15

    The release of major and trace elements from recycled concrete aggregates used in an asphalt covered road sub-base has been monitored for more than 4 years. A similar test field without an asphalt cover, directly exposed to air and rain, and an asphalt covered reference field with natural aggregates in the sub-base were also included in the study. It was found that the pH of the infiltration water from the road sub-base with asphalt covered concrete aggregates decreased from 12.6 to below pH 10 after 2.5 years of exposure, whereas this pH was reached within only one year for the uncovered field. Vertical temperature profiles established for the sub-base, could explain the measured infiltration during parts of the winter season. When the release of major and trace elements as function of field pH was compared with pH dependent release data measured in the laboratory, some similar pH trends were found. The field concentrations of Cd, Ni, Pb and Zn were found to be low throughout the monitoring period. During two of the winter seasons, a concentration increase of Cr and Mo was observed, possibly due to the use of de-icing salt. The concentrations of the trace constituents did not exceed Norwegian acceptance criteria for ground water and surface water Class II. PMID:22554532

  17. Field site leaching from recycled concrete aggregates applied as sub-base material in road construction.

    PubMed

    Engelsen, Christian J; Wibetoe, Grethe; van der Sloot, Hans A; Lund, Walter; Petkovic, Gordana

    2012-06-15

    The release of major and trace elements from recycled concrete aggregates used in an asphalt covered road sub-base has been monitored for more than 4 years. A similar test field without an asphalt cover, directly exposed to air and rain, and an asphalt covered reference field with natural aggregates in the sub-base were also included in the study. It was found that the pH of the infiltration water from the road sub-base with asphalt covered concrete aggregates decreased from 12.6 to below pH 10 after 2.5 years of exposure, whereas this pH was reached within only one year for the uncovered field. Vertical temperature profiles established for the sub-base, could explain the measured infiltration during parts of the winter season. When the release of major and trace elements as function of field pH was compared with pH dependent release data measured in the laboratory, some similar pH trends were found. The field concentrations of Cd, Ni, Pb and Zn were found to be low throughout the monitoring period. During two of the winter seasons, a concentration increase of Cr and Mo was observed, possibly due to the use of de-icing salt. The concentrations of the trace constituents did not exceed Norwegian acceptance criteria for ground water and surface water Class II.

  18. Phase Preference by Active, Acetate-Utilizing Bacteria at the Rifle, CO Integrated Field Research Challenge Site

    SciTech Connect

    Kerkhof, L.; Williams, K.H.; Long, P.E.; McGuinness, L.

    2011-02-21

    Previous experiments at the Rifle, Colorado Integrated Field Research Challenge (IFRC) site demonstrated that field-scale addition of acetate to groundwater reduced the ambient soluble uranium concentration. In this report, sediment samples collected before and after acetate field addition were used to assess the active microbes via {sup 13}C acetate stable isotope probing on 3 phases [coarse sand, fines (8-approximately 150 {micro}m), groundwater (0.2-8 {micro}m)] over a 24-day time frame. TRFLP results generally indicated a stronger signal in {sup 13}C-DNA in the 'fines' fraction compared to the sand and groundwater. Before the field-scale acetate addition, a Geobacter-like group primarily synthesized {sup 13}C-DNA in the groundwater phase, an alpha Proteobacterium primarily grew on the fines/sands, and an Acinetobacter sp. and Decholoromonas-like OTU utilized much of the {sup 13}C acetate in both groundwater and particle-associated phases. At the termination of the field-scale acetate addition, the Geobacter-like species was active on the solid phases rather than the groundwater, while the other bacterial groups had very reduced newly synthesized DNA signal. These findings will help to delineate the acetate utilization patterns of bacteria in the field and can lead to improved methods for stimulating distinct microbial populations in situ.

  19. Summary of field operations Technical Area I well PGS-1. Site-Wide Hydrogeologic Characterization Project

    SciTech Connect

    Fritts, J.E.; McCord, J.P.

    1995-02-01

    The Environmental Restoration (ER) Project at Sandia National Laboratories, New Mexico is managing the project to assess and, when necessary, to remediate sites contaminated by the lab operations. Within the ER project, the site-wide hydrogeologic characterization task is responsible for the area-wide hydrogeologic investigation. The purpose of this task is to reduce the uncertainty about the rate and direction of groundwater flow beneath the area and across its boundaries. This specific report deals with the installation of PGS-1 monitoring well which provides information on the lithology and hydrology of the aquifer in the northern area of the Kirtland Air Force Base. The report provides information on the well design; surface geology; stratigraphy; structure; drilling, completion, and development techniques; and borehole geophysics information.

  20. [Field measurement of Gobi surface emissivity spectrum at Dunhuang calibration site of China].

    PubMed

    Zhang, Yong; Li, Yuan; Rong, Zhi-guo; Hu, Xiu-qing; Zhang, Li-jun; Liu, Jing-jing

    2009-05-01

    Gobi surface emissivity spectrum of Dunhuang radiometric calibration site of China is one of the key factors to calibrate the thermal infrared remote sensors using land surface. Based on the iterative spectrally smooth temperature/emissivity separation (ISSTES)algorithm, Dunhuang Gobi surface emissivity spectrum was measured using BOMEM MR154 Fourier transform spectroradiometer and Infrared Golden Board. Emissivity spectrum data were obtained at different time and locations. These spectrum data were convolved with the channel response function of CE312 radiometer and compared with the channel emissivity measured by the same instrument. The results showed that the difference between these two kinds of channel emissivity was within 0.012 and exhibited a good consistency. With these measured emissivity spectra, all of the mainstream thermal infrared remote sensors can be calibrated using Dunhuang Gobi surface at radiometric calibration site of China.

  1. Technical procedures for ecology: Environmental field program, Deaf Smith County Site, Texas: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    This volume contains Technical Procedures pursuant to the Land Use Site Study Plan including walkover surveys for threatened, endangered, or candidate species; vegetation classification and mapping; reclamation planning; wetland and floodplain determination and characterization of playas; wildlife habitat mapping methods; mammal sampling; bird survey methods; reptile and amphibian survey methods; preexisting environmental; stress and disturbance studies methods; voucher specimens for plants; and voucher specimens to wildlife. 9 refs., 5 figs., 1 tab.

  2. Remote sensing strategy at the first Atmospheric Radiation Measurement field site

    SciTech Connect

    Wesely, M.L.; Griffin, J.W.

    1994-07-01

    The Atmospheric Radiation Measurement (ARM) Program was initiated in 1990 by the US Department of Energy to improve climate model simulations of radiative energy transport and cloud formation, maintenance, and dissipation. ARM stresses the modeling of phenomena occurring at subgrid scales in general circulation models (GCMs). Measurements to support the modeling research will be made at three primary locations. The central facility, the primary location at the Southern Great Plains (SGP) site for study of radiative transfer, uses ground-based remote sensing instrumentation to observe radiation and the atmospheric properties that affect it. Remote sensing instruments and balloon-borne sounding systems installed at several boundary facilities on the perimeter of the overall Cloud and Radiation Testbed (CART) site evaluate vertical profiles of wind, temperature, and humidity. These observations are needed to run single-column models derived from GCMs for a single grid square with an area equivalent to the overall CART area. Observations of local meteorological conditions, air-surface exchange, and solar and infrared radiation at up to 23 extended facilities scattered throughout the CART site provide the surface boundary information needed in the single-column models. Finally, auxiliary facilities at the central facility and at a few locations within 10 km of the central facility will contain whole-sky imaging systems to map cloud characteristics. The purpose of this presentation is to describe the strategy used to obtain remote sensing instrumentation for continuous operation at the central facility.

  3. Archaeological field survey automation: concurrent multisensor site mapping and automated analysis

    NASA Astrophysics Data System (ADS)

    Józefowicz, Mateusz; Sokolov, Oleksandr; Meszyński, Sebastian; Siemińska, Dominika; Kołosowski, Przemysław

    2016-04-01

    ABM SE develops mobile robots (rovers) used for analog research of Mars exploration missions. The rovers are all-terrain exploration platforms, carrying third-party payloads: scientific instrumentation. "Wisdom" ground penetrating radar for Exomars mission has been tested onboard, as well as electrical resistivity module and other devices. Robot has operated in various environments, such as Central European countryside, Dachstein ice caves or Sahara, Morocco (controlled remotely via satellite from Toruń, Poland. Currently ABM SE works on local and global positioning system for a Mars rover basing on image and IMU data. This is performed under a project from ESA. In the next Mars rover missions a Mars GIS model will be build, including an acquired GPR profile, DEM and regular image data, integrated into a concurrent 3D terrain model. It is proposed to use similar approach in surveys of archaeological sites, especially those, where solid architecture remains can be expected at shallow depths or being partially exposed. It is possible to deploy a rover that will concurrently map a selected site with GPR, 2D and 3D cameras to create a site model. The rover image processing algorithms are capable of automatic tracing of distinctive features (such as exposed structure remains on a desert ground, differences in color of the ground, etc.) and to mark regularities on a created map. It is also possible to correlate the 3D map with an aerial photo taken under any angle to achieve interpretation synergy. Currently the algorithms are an interpretation aid and their results must be confirmed by a human. The advantages of a rover over traditional approaches, such as a manual cart or a drone include: a) long hours of continuous work or work in unfavorable environment, such as high desert, frozen water pools or large areas, b) concurrent multisensory data acquisition, c) working from the ground level enables capturing of sites obstructed from the air (trees), d) it is possible to

  4. Summary of South Fence Road phase II 1993 field operations at Site SFR-4

    SciTech Connect

    Foutz, W.L.; McCord, J.P.

    1996-05-01

    This report is a basic data report for field operations associated with the drilling, logging, completion, and development of South Fence Road Wells SFR-4P and SFR-4T. These test/monitoring wells were installed as part of Sandia National Laboratories, New Mexico, Environmental Restoration Project.

  5. Summary of South Fence Road phase II 1993 field operations at site SFR-3

    SciTech Connect

    Foutz, W.L.; McCord, J.P.

    1996-05-01

    This report is a basic data report fro field operations associated with the drilling, logging, completion, and development of South Fence Road Wells SFR-3P and SFR-3T. These test/monitoring wells were installed as part of Sandia National Laboratories, New Mexico, Environmental Restoration Project.

  6. Accountability Issues for Instructional Leadership: Field Research, Site-Based Management, and a Campus Action Plan.

    ERIC Educational Resources Information Center

    Maurice, John M.; Karr-Kidwell, P. J.

    The purpose of this study was to use data collected from a field research project to enable teachers and instructional leaders to understand and overcome the problems associated with high-stakes testing, especially as they relate to the narrowing of the curriculum. In spring 2001, 27 of the 48 teachers at a middle school in Texas responded to a…

  7. Characterizing The Microbial Community In A TCE DNAPL Site: SABRE Column And Field Studies

    EPA Science Inventory

    The SABRE (Source Area BioREmediation) project is evaluating accelerated anaerobic bioremediation of chlorinated solvents in areas of high concentration, such as DNAPL source areas. In support of a field scale pilot test, column studies were conducted to design the system and ob...

  8. MULTI-SITE FIELD EVALUATION OF CANDIDATE SAMPLERS FOR MEASURING COARSE-MODE PM

    EPA Science Inventory

    In response to expected changes to the National Ambient Air Quality Standards for particulate matter, comprehensive field studies were conducted to evaluate the performance of sampling methods for measuring coarse mode aerosols (i.e. PMc). Five separate PMc sampling approaches w...

  9. Scenario-based modelling of mass transfer mechanisms at a petroleum contaminated field site-numerical implications.

    PubMed

    Vasudevan, M; Nambi, Indumathi M; Suresh Kumar, G

    2016-06-15

    Knowledge about distribution of dissolved plumes and their influencing factors is essential for risk assessment and remediation of light non-aqueous phase liquid contamination in groundwater. Present study deals with the applicability of numerical model for simulating various hydro-geological scenarios considering non-uniform source distribution at a petroleum contaminated site in Chennai, India. The complexity associated with the hydrogeology of the site has limited scope for on-site quantification of petroleum pipeline spillage. The change in fuel composition under mass-transfer limited conditions was predicted by simultaneously comparing deviations in aqueous concentrations and activity coefficients (between Raoult's law and analytical approaches). The effects of source migration and weathering on the dissolution of major soluble fractions of petroleum fuel were also studied in relation to the apparent change in their activity coefficients and molar fractions. The model results were compared with field observations and found that field conditions were favourable for biodegradation, especially for the aromatic fraction (benzene and toluene (nearly 95% removal), polycyclic aromatic hydrocarbons (up to 65% removal) and xylene (nearly 45% removal). The results help to differentiate the effect of compositional non-ideality from rate-limited dissolution towards tailing of less soluble compounds (alkanes and trimethylbenzene). Although the effect of non-ideality decreased with distance from the source, the assumption of spatially varying residual saturation could effectively illustrate post-spill scenario by estimating the consequent decrease in mass transfer rate.

  10. Technical procedures for utilities and solid waste: Environmental Field Program, Deaf Smith County site, Texas: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    The evaluation of environmental issues and concerns and the addressing of statutory requirements are fundamental parts in the characterization of the site in Deaf Smith County, Texas for the US Department of Energy's Salt Repository Project (SRP). To ensure that the environmental field program comprehensively addresses the issues and requirements of the project, a site study plan (SSP) has been prepared for Utilities and Solid Waste considerations. This technical procedure (TP) has been developed to implement the field program described in the Utilities and Solid Waste Site Study Plan. The purpose and scope of the Utilities and Solid Waste Technical Procedure is to develop and implement a data collection procedure to fulfill the data base needs of the Utilities and Solid Waste SSP. The procedure describes a method of obtaining, assessing and verifying the capabilities of the regional service utilities and disposal contractors. This data base can be used to identify a preferred service source for the engineering contractor. The technical procedure was produced under the guidelines established in Technical Administrative Procedure No. 1.0, Preparation, Review and Approval of Technical Procedures.

  11. Scenario-based modelling of mass transfer mechanisms at a petroleum contaminated field site-numerical implications.

    PubMed

    Vasudevan, M; Nambi, Indumathi M; Suresh Kumar, G

    2016-06-15

    Knowledge about distribution of dissolved plumes and their influencing factors is essential for risk assessment and remediation of light non-aqueous phase liquid contamination in groundwater. Present study deals with the applicability of numerical model for simulating various hydro-geological scenarios considering non-uniform source distribution at a petroleum contaminated site in Chennai, India. The complexity associated with the hydrogeology of the site has limited scope for on-site quantification of petroleum pipeline spillage. The change in fuel composition under mass-transfer limited conditions was predicted by simultaneously comparing deviations in aqueous concentrations and activity coefficients (between Raoult's law and analytical approaches). The effects of source migration and weathering on the dissolution of major soluble fractions of petroleum fuel were also studied in relation to the apparent change in their activity coefficients and molar fractions. The model results were compared with field observations and found that field conditions were favourable for biodegradation, especially for the aromatic fraction (benzene and toluene (nearly 95% removal), polycyclic aromatic hydrocarbons (up to 65% removal) and xylene (nearly 45% removal). The results help to differentiate the effect of compositional non-ideality from rate-limited dissolution towards tailing of less soluble compounds (alkanes and trimethylbenzene). Although the effect of non-ideality decreased with distance from the source, the assumption of spatially varying residual saturation could effectively illustrate post-spill scenario by estimating the consequent decrease in mass transfer rate. PMID:27017268

  12. Modelling field scale water partitioning using on-site observations in sub-Saharan rainfed agriculture

    NASA Astrophysics Data System (ADS)

    Makurira, H.; Savenije, H. H. G.; Uhlenbrook, S.

    2009-08-01

    Smallholder rainfed farming systems generally realise sub-optimal crop yields which are largely attributed to dry spell occurrences during crop growth stages. However, with improved farming practices, it seems possible to significantly increase yield levels even with little and highly variable rainfall. The presented results follow research conducted in the Makanya catchment in northern Tanzania where gross rainfall amounts to less than 400 mm/season which is insufficient to support staple food crops (e.g. maize). Alternative cultivation techniques such as runoff harvesting and in-field micro-storage structures are compared. These techniques aim to reduce soil and nutrient loss from the field but, more importantly, promote in-field infiltration and water retention. Water balance components have been observed in order to study water partitioning processes under different cultivation techniques. Based on rainfall, soil evaporation, transpiration, runoff and soil moisture measurements, a water balance model has been developed to simulate soil moisture variations over the growing season. It appears that about 50% of the diverted water leaves the root zone through deep percolation. Modelling shows that during the field trials the average productive transpiration flow ranged between 1.1-1.4 mm d-1 in the trial plots compared to 0.7-1.0 mm d-1 under traditional tillage practice. Productive transpiration processes accounted for 23-29% while losses to deep percolation accounted for 33-48% of the available water. Conclusions from the research are that the innovations tested are effective in enhancing soil moisture retention at field scale and that diversions allow crop growth moisture conditions to be attained with early rains. It is also concluded that there is more scope for efficient utilisation of the diverted runoff water if storage structures could be installed to regulate water flow to the root zone when required.

  13. Modelling field scale water partitioning using on-site observations in sub-Saharan rainfed agriculture

    NASA Astrophysics Data System (ADS)

    Makurira, H.; Savenije, H. H. G.; Uhlenbrook, S.

    2010-04-01

    Smallholder rainfed farming systems generally realise sub-optimal crop yields which are largely attributed to dry spell occurrences during crop growth stages. However, through the introduction of appropriate farming practices, it is possible to substantially increase yield levels even with little and highly variable rainfall. The presented results follow research conducted in the Makanya catchment in northern Tanzania where gross rainfall amounts to less than 400 mm/season which is insufficient to support staple food crops (e.g. maize). The yields from farming system innovations (SIs), which are basically alternative cultivation techniques, are compared against traditional farming practices. The SIs tested in this research are runoff harvesting used in combination with in-field trenches and soil bunds (fanya juus). These SIs aim to reduce soil and nutrient loss from the field and, more importantly, promote in-field infiltration and water retention. Water balance components have been observed in order to study water partitioning processes for the "with" and "without" SI scenarios. Based on rainfall, soil evaporation, transpiration, runoff and soil moisture measurements, a water balance model has been developed to simulate soil moisture variations over the growing season. Simulation results show that, during the field trials, the average productive transpiration flow ranged between 1.1-1.4 mm d-1 in the trial plots compared to 0.7-1.0 mm d-1 under traditional tillage practice. Productive transpiration processes accounted for 23-29% while losses to deep percolation accounted for 33-48% of the available water. The field system has been successfully modelled using the spreadsheet-based water balance 1-D model. Conclusions from the research are that the SIs that were tested are effective in enhancing soil moisture retention at field scale and that diversions allow crop growth moisture conditions to be attained with early rains. From the partitioning analysis, it is also

  14. Spatial Distribution of Uranium in Groundwater and Associated Geologic Material at the NABIR Field Research Center Site, Oak Ridge, Tennessee

    NASA Astrophysics Data System (ADS)

    Phillips, D. H.; Watson, D. B.

    2001-05-01

    The Natural and Accelerated Bioremediation Research Program (NABIR) has established a Field Research Center (FRC) on the Oak Ridge Reservation in Oak Ridge, Tennessee. The FRC provides a site for investigators to conduct research and obtain samples related to in situ bioremediation. This site is in the form of four buried unlined ponds where uranium and other contaminants were disposed in nitric acid for 32 years. In 1984, the ponds were neutralized with limestone, RCRA capped and paved with a parking lot. Analysis of groundwater and geologic material sampled from the site show that uranium is preferentially migrating away from the ponds and towards the nearby Bear Creek. Preferential flow appears to be associated with an ancient buried stream bed and remnant fractures in the saprolite where the uranium content of the groundwater is as high as 7 ppm. Due to the greater discharge of the contaminant source in this portion of the regolith, there is higher weathering of the shallow regolith (top 20 ft)and a greater accumulation of uranium compared to other sections of geologic material surrounding the disposal site.

  15. Site Environmental Report for Calendar Year 2007. DOE Operations at The Boeing Company, Santa Susana Field Laboratory, Area IV

    SciTech Connect

    Liu, Ning; Rutherford, Phil; Lenox, Art; Blair, Lori; Amar, Ravnesh; Costa, Paul; Galvez, Lydia; Jameson, Blythe; Galvez, Lydia

    2008-09-30

    This Annual Site Environmental Report (ASER) for 2007 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder components. All nuclear work was terminated in 1988; all subsequent radiological work has been directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. In May 2007, the D&D operations in Area IV were suspended until DOE completes the SSFL Area IV Environmental Impact Statement (EIS). The environmental monitoring programs were continued throughout the year. Results of the radiological monitoring program for the calendar year 2007 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling. All radioactive wastes are processed for disposal at DOE disposal sites and/or other licensed sites approved by DOE for radioactive waste disposal. No liquid radioactive wastes were released into the environment in 2007.

  16. Rocketdyne division, envionmental monitoring and facility effluent. Annual report, De Soto and Santa Susana Field Laboratories Sites, 1988

    SciTech Connect

    Moore, J. D.

    1989-05-01

    Environmental and facility effluent radioactivity monitoring at the Rocketdyne Division of Rockwell International is performed by the Radiation and Nuclear Safety Group of the Health, Safety, and Environment Department. Soil and surface water are routinely sampled to a distance of 16 km from division sites. Groundwater from Santa Susana Field Laboratories (SSFL) supply water wells and other test wells is periodically sampled to measure radioactivity. Continuous ambient air sampling and direct radiation monitoring by thermoluminescent dosimetry are performed at several on-site and off-site locations for measuring airborne radioactivity concentrations and site ambient radiation levels. Radioactivity in effluents discharged to the atmosphere from nuclear facilities is continually sampled and monitored to assure that amounts released to uncontrolled areas are below appropriate limits. These procedures also help identify processes that may require additional engineering safeguards to minimize radioactivity in such discharges. In addition, selected nonradioactive chemical constituent concentrations in surface water discharged to uncontrolled areas are measured. The environmental radioactivity reported herein is attributed to natural sources and to residual fallout of radioactive material from past atmospheric testing of nuclear devices.

  17. Onchocerciasis transmission levels and Simulium damnosum complex biting activity at riverside and rice field sites in Sierra Leone.

    PubMed

    Davies, J B; Beech-Garwood, P A; Thomson, M C; McMahon, J E

    1988-10-01

    Biting densities of the Simulium damnosum Theobald complex of blackflies and their levels of parasitism by Onchocerca volvulus (Leuckart) were compared at two ecologically contrasted sites in the Southern Province of Sierre Leone, West Africa: by the Tabe riverside close to Gbaiima village where onchocerciasis is hyperendemic (63.1% positive skin-snips) and in open rice fields 2 km from the mesoendemic (54.9%) village of Senehun. Using a combination of morphometric and enzyme electrophoresis techniques, the primary vector was found to belong to the S.sanctipauli subcomplex and was most probably S.soubrense 'B' (sensu Post, 1986). In the wet season biting activity took place throughout the day at the village, but had morning and evening peaks in the rice fields. Transmission of O.volvulus was detected at the village in all months except February-April, while in the rice fields it was detected only during September-November and May at one tenth the level of the village. There was a significant difference between the two sites in the proportion of parous flies carrying third stage larvae in the head, but not of other larval stages. PMID:2980195

  18. Application of in situ biosparging to remediate a petroleum-hydrocarbon spill site: field and microbial evaluation.

    PubMed

    Kao, C M; Chen, C Y; Chen, S C; Chien, H Y; Chen, Y L

    2008-02-01

    In this study, a full-scale biosparging investigation was conducted at a petroleum-hydrocarbon spill site. Field results reveal that natural attenuation was the main cause of the decrease in major contaminants [benzene, toluene, ethylbenzene, and xylenes (BTEX)] concentrations in groundwater before the operation of biosparging system. Evidence of the occurrence of natural attenuation within the BTEX plume includes: (1) decrease of DO, nitrate, sulfate, and redox potential, (2) production of dissolved ferrous iron, sulfide, methane, and CO(2), (3) decreased BTEX concentrations along the transport path, (4) increased microbial populations, and (5) limited spreading of the BTEX plume. Field results also reveal that the operation of biosparging caused the shifting of anaerobic conditions inside the plume to aerobic conditions. This variation can be confirmed by the following field observations inside the plume due to the biosparging process: (1) increase in DO, redox potential, nitrate, and sulfate, (2) decrease dissolved ferrous iron, sulfide, and methane, (3) increased total cultivable heterotrophs, and (4) decreased total cultivable anaerobes as well as methanogens. Results of polymerase chain reaction, denaturing gradient gel electrophoresis, and nucleotide sequence analysis reveal that three BTEX biodegraders (Candidauts magnetobacterium, Flavobacteriales bacterium, and Bacteroidetes bacterium) might exist at this site. Results show that more than 70% of BTEX has been removed through the biosparging system within a 10-month remedial period at an averaged groundwater temperature of 18 degrees C. This indicates that biosparging is a promising technology to remediate BTEX contaminated groundwater.

  19. Incorporating dynamic root growth enhances the performance of Noah-MP at two contrasting winter wheat field sites

    NASA Astrophysics Data System (ADS)

    Gayler, Sebastian; Wöhling, Thomas; Ingwersen, Joachim; Wizemann, Hans-Dieter; Warrach-Sagi, Kirsten; Attinger, Sabine; Streck, Thilo; Wulmeyer, Volker

    2014-05-01

    Interactions between the soil, the vegetation, and the atmospheric boundary layer require close attention when predicting water fluxes in the hydrogeosystem, agricultural systems, weather and climate. However, land-surface schemes used in large scale models continue to show deficits in consistently simulating fluxes of water and energy from the subsurface through vegetation layers to the atmosphere. In this study, the multi-physics version of the Noah land-surface model (Noah-MP) was used to identify the processes, which are most crucial for a simultaneous simulation of water and heat fluxes between land-surface and the lower atmosphere. Comprehensive field data sets of latent and sensible heat fluxes, ground heat flux, soil moisture, and leaf area index from two contrasting field sites in South-West Germany are used to assess the accuracy of simulations. It is shown that an adequate representation of vegetation-related processes is the most important control for a consistent simulation of energy and water fluxes in the soil-plant-atmosphere system. In particular, using a newly implemented sub-module to simulate root growth dynamics has enhanced the performance of Noah-MP at both field sites. We conclude that further advances in the representation of leaf area dynamics and root/soil moisture interactions are the most promising starting points for improving the simulation of feedbacks between the sub-soil, land-surface and atmosphere in fully-coupled hydrological and atmospheric models.

  20. Observational Assessment Of Field Trial Site For The Implementation Of A PACS Network

    NASA Astrophysics Data System (ADS)

    Coristine, Marjorie A.; Tombaugh, Jo W.; Dillon, Richard F.

    1989-05-01

    In building an integrated radiological information system (IRIS) and preparing for field trials at a large hospital, it was necessary to consider the working conventions and needs of radiologists and clinicians. It was also necessary to analyse the current practices involved in the requesting, reading, and reporting of x-rays. Because IRIS is designed to be a mechanism for effective consultations, an understanding of the conventions and nature of x-ray related consultations was also needed. In order to gain this understanding, two observational studies were conducted. The first addressed issues of x-ray related behavior in the emergency department, and the second assessed the task requirements of radiologists when reporting x-rays or consulting with other physicians about x-rays. These findings had major implications for the design of IRIS and for conducting the field trials.

  1. New archaeointensity results from archaeological sites and variation of the geomagnetic field intensity for the last 7 millennia in Greece

    NASA Astrophysics Data System (ADS)

    De Marco, E.; Spatharas, V.; Gómez-Paccard, M.; Chauvin, A.; Kondopoulou, D.

    In this study six new intensity determinations are presented, obtained from five well dated archaeological sites, located in northern Greece and in Paros, Cyclades Islands. The fired structures consisted of ceramic and pottery kilns belonging to the Hellenistic, Roman and Byzantine periods. Between 8 and 21 samples of highly fired baked clays, tiles and bricks were taken, homogeneously distributed over the structures. The samples were analysed using the classical Thellier method, providing the past intensities and directions of the geomagnetic field recorded at each site. The intensity values have been corrected for anisotropy of thermal remanent magnetisation and cooling rate effects. Differences in the mean archaeointensities per site ranging from 1% to 11%, before and after TRM anisotropy and cooling rate corrections, were obtained. The new results indicate a decrease of 20% of the geomagnetic field strength in Greece, during the last four centuries BC. In order to compare our results with previously published data, a catalogue of archaeo- and palaeointensity results for the Aegean area has been established, covering the last 7 millennia. It consists of 336 data from Greece, western Turkey and Former Yugoslavia, collected from various authors. Weighting factors have been applied to these data, that then have been treated with a hierarchical Bayesian modelling, and a geomagnetic field intensity variation curve for Greece was constructed. A good agreement is observed when comparing the curve for Greece with the Bulgarian secular variation curve (SVC) for intensity. Satisfactory coincidence is also found with the archaeointensity data from Mesopotamia. Despite the presence of some time gaps, a more precise secular variation intensity curve has been constructed for Greece which, combined with a forthcoming directional SVC, will help for dating purposes.

  2. Field monitoring and performance evaluation of a field-scale in-well aeration system at a gasoline-contaminated site.

    PubMed

    Hall, B L; Lachmar, T E; Dupont, R R

    2001-03-30

    Several in-well aeration (IWA) technologies have been used since the early 1990s, but few field studies have been performed to evaluate the extent of water circulation around IWA systems. In this study, 27 discrete monitoring points (MPs) were installed at a gasoline-contaminated site to assess the efficacy of IWA. Pressure transducers and dissolved oxygen (DO) probes were sealed into the MPs, allowing them to be used to characterize subsurface changes in total head and DO with depth, distance and orientation from a central injection well. No change in DO or in hydrocarbon total mass or distribution occurred across the site during two trials (41 and 20 days) of the system. Water level fluctuations during the trials were similar in all MPs, and were due to seasonal water table changes and rainfall events. No circulation cell was established around the IWA well after 41 days of operation, and the impact of the well extended less than 90cm from it. Groundwater only circulated through the sand pack around the well. Little, if any, recharge occurred through the lower screen. Silt accumulated in the well, limiting its operation time, even with a fabric filter sock over the lower screen. Obviously, IWA was ineffective at this site, probably because the horizontal hydraulic conductivity (K(h)) of the soil opposite the lower screen was low (0.09cm per day) and because the distance between the two screens was short relative to the borehole radius. Long remediation times would likely make IWA unattractive at this or other sites where the K(h) of the soil is so low that the air injection rate would have to be low to prevent blowing the well dry. PMID:11230915

  3. Field monitoring and performance evaluation of a field-scale in-well aeration system at a gasoline-contaminated site.

    PubMed

    Hall, B L; Lachmar, T E; Dupont, R R

    2001-03-30

    Several in-well aeration (IWA) technologies have been used since the early 1990s, but few field studies have been performed to evaluate the extent of water circulation around IWA systems. In this study, 27 discrete monitoring points (MPs) were installed at a gasoline-contaminated site to assess the efficacy of IWA. Pressure transducers and dissolved oxygen (DO) probes were sealed into the MPs, allowing them to be used to characterize subsurface changes in total head and DO with depth, distance and orientation from a central injection well. No change in DO or in hydrocarbon total mass or distribution occurred across the site during two trials (41 and 20 days) of the system. Water level fluctuations during the trials were similar in all MPs, and were due to seasonal water table changes and rainfall events. No circulation cell was established around the IWA well after 41 days of operation, and the impact of the well extended less than 90cm from it. Groundwater only circulated through the sand pack around the well. Little, if any, recharge occurred through the lower screen. Silt accumulated in the well, limiting its operation time, even with a fabric filter sock over the lower screen. Obviously, IWA was ineffective at this site, probably because the horizontal hydraulic conductivity (K(h)) of the soil opposite the lower screen was low (0.09cm per day) and because the distance between the two screens was short relative to the borehole radius. Long remediation times would likely make IWA unattractive at this or other sites where the K(h) of the soil is so low that the air injection rate would have to be low to prevent blowing the well dry.

  4. Field Evaluation of the Restorative Capacity of the Aquifer Downgradient of a Uranium In-Situ Recovery Mining Site

    SciTech Connect

    Reimus, Paul William

    2015-05-22

    A two-part field study was conducted in Smith Ranch-Highland in-situ recovery (ISR) near Douglas, Wyoming, to evaluate the restorative capacity of the aquifer downgradient (i.e., hydrologically downstream) of a Uranium ISR mining site with respect to the transport of uranium and other potential contaminants in groundwater after mining has ceased. The study was partially conducted by checking the Uranium content and the alkalinity of separate wells, some wells had been restored and others had not. A map and in-depth procedures of the study are included.

  5. Thermal vacancies in random alloys in the single-site mean-field approximation

    NASA Astrophysics Data System (ADS)

    Ruban, A. V.

    2016-04-01

    A formalism for the vacancy formation energies in random alloys within the single-site mean-filed approximation, where vacancy-vacancy interaction is neglected, is outlined. It is shown that the alloy configurational entropy can substantially reduce the concentration of vacancies at high temperatures. The energetics of vacancies in random Cu0.5Ni0.5 alloy is considered as a numerical example illustrating the developed formalism. It is shown that the effective formation energy increases with temperature, however, in this particular system it is still below the mean value of the vacancy formation energy, which would correspond to the vacancy formation energy in a homogeneous model of a random alloy, such as given by the coherent potential approximation.

  6. Aquifer recharge with reclaimed water in the Llobregat Delta. Laboratory batch experiments and field test site.

    NASA Astrophysics Data System (ADS)

    Tobella, J.

    2010-05-01

    Summary Spain, as most other Mediterranean countries, faces near future water shortages, generalized pollution and loss of water dependent ecosystems. Aquifer recharge represents a promising option to become a source for indirect potable reuse purposes but presence of pathogens as well as organic and inorganic pollutants should be avoided. To this end, understanding the processes of biogeochemical degradation occurring within the aquifer during infiltration is capital. A set of laboratory batch experiments has been assembled in order to assess the behaviour of selected pesticides, drugs, estrogens, surfactant degradation products, biocides and phthalates under different redox conditions. Data collected during laboratory experiments and monitoring activities at the Sant Vicenç dels Horts test site will be used to build and calibrate a numerical model (i) of the physical-chemical-biochemical processes occurring in the batches and (ii) of multicomponent reactive transport in the unsaturated/saturated zone at the test site. Keywords Aquifer recharge, batch experiments, emerging micropollutants, infiltration, numerical model, reclaimed water, redox conditions, Soil Aquifer Treatment (SAT). 1. Introduction In Spain, the Llobregat River and aquifers, which supply water to Barcelona, have been overexploited for years and therefore, suffer from serious damages: the river dries up on summer, riparian vegetation has disappeared and seawater has intruded the aquifer. In a global context, solutions to water stress problems are urgently needed yet must be sustainable, economical and safe. Recent developments of analytical techniques detect the presence of the so-called "emerging" organic micropollutants in water and soils. Such compounds may affect living organisms when occurring in the environment at very low concentrations (microg/l or ng/l). In wastewater and drinking water treatment plants, a remarkable removal of these chemicals from water can be obtained only using

  7. MICORE: DUNE EROSION AND OVERWASH MODEL VALIDATION WITH DATA FROM NINE EUROPEAN FIELD SITES (Invited)

    NASA Astrophysics Data System (ADS)

    van Dongeren, A.; Bolle, A.; Roelvink, J.; Vousdoukas, M. I.; Plomaritis, T.; Williams, J.; Armaroli, C.; Idier, D.; van Geer, P.; van Thiel de Vries, J.; Haerens, P.; Taborda, R.; Benavente, J.; Trifonova, E.; Ciavola, P.; Balouin, Y.; Eftimova, P.

    2009-12-01

    The European Union funded project MICORE - Morphological Impacts and COastal Risks induced by Extreme storm events - has as the main objective to develop and demonstrate on-line tools for reliable predictions of the morphological impact of marine storm events in support of civil protection mitigation strategies. Severe storms have historically affected European coastlines and the impact of each storm has been evaluated in different ways in different countries. The project is specifically targeted to contribute to the development of a common probabilistic mapping of the morphological impact of marine storms and to the production of early warning and information systems to support long-term disaster reduction. The first step in the modeling effort is to compare the results of a newly-developed coastal response model called XBeach (Roelvink et al, accepted) with existing off-the-shelf models, using data gathered at nine different sites in the EU. The second step is to develop a prototype operational system which will be able to predict coastal erosion a few days ahead. Here we present the first results of beach profile hindcasting with XBeach using recently measured coastal data acquired under storm conditions at eight European sites, including a comparison to model results obtained with off-the-shelf models. The results show consistently that the XBeach has skill in predicting the coastal profile, albeit that in most cases the erosion around the mean water line is overpredicted and the depositions at the lower beach face are overpredicted. The causes for this model effect are under active investigation but not resolved yet. Likely candidates are the modeling of onshore (asymmetry) transports which reduces the offshore transports due to undertow (currents) or the modeling of sediment motion in the swash zone.

  8. Microbiological and Geochemical Heterogeneity in an In Situ Uranium Bioremediation Field Site

    PubMed Central

    Vrionis, Helen A.; Anderson, Robert T.; Ortiz-Bernad, Irene; O'Neill, Kathleen R.; Resch, Charles T.; Peacock, Aaron D.; Dayvault, Richard; White, David C.; Long, Philip E.; Lovley, Derek R.

    2005-01-01

    The geochemistry and microbiology of a uranium-contaminated subsurface environment that had undergone two seasons of acetate addition to stimulate microbial U(VI) reduction was examined. There were distinct horizontal and vertical geochemical gradients that could be attributed in large part to the manner in which acetate was distributed in the aquifer, with more reduction of Fe(III) and sulfate occurring at greater depths and closer to the point of acetate injection. Clone libraries of 16S rRNA genes derived from sediments and groundwater indicated an enrichment of sulfate-reducing bacteria in the order Desulfobacterales in sediment and groundwater samples. These samples were collected nearest the injection gallery where microbially reducible Fe(III) oxides were highly depleted, groundwater sulfate concentrations were low, and increases in acid volatile sulfide were observed in the sediment. Further down-gradient, metal-reducing conditions were present as indicated by intermediate Fe(II)/Fe(total) ratios, lower acid volatile sulfide values, and increased abundance of 16S rRNA gene sequences belonging to the dissimilatory Fe(III)- and U(VI)-reducing family Geobacteraceae. Maximal Fe(III) and U(VI) reduction correlated with maximal recovery of Geobacteraceae 16S rRNA gene sequences in both groundwater and sediment; however, the sites at which these maxima occurred were spatially separated within the aquifer. The substantial microbial and geochemical heterogeneity at this site demonstrates that attempts should be made to deliver acetate in a more uniform manner and that closely spaced sampling intervals, horizontally and vertically, in both sediment and groundwater are necessary in order to obtain a more in-depth understanding of microbial processes and the relative contribution of attached and planktonic populations to in situ uranium bioremediation. PMID:16204552

  9. Microbiological and Geochemical Heterogeneity in an In Situ Uranium Bioremediation Field Site

    SciTech Connect

    Vrionis, Helen A.; Anderson, Robert T.; Ortiz-Bernad, Irene; O'Neill, Kathleen R.; Resch, Charles T.; Peacock, Aaron D.; Dayvault, Richard; White, David C.; Long, Philip E.; Lovley, Derek R.

    2005-12-01

    The geochemistry and microbiology of a uranium-contaminated subsurface environment that had undergone two seasons of acetate addition to stimulate microbial U(VI) reduction was examined. There were distinct horizontal and vertical geochemical gradients that could be attributed in large part to the manner in which acetate was distributed in the aquifer with more reduction of F e(III) and sulfate at deeper depths and closer to the point of acetate injection. 16S rDNA clone libraries derived from sediments and groundwater indicated that the there was an enrichment of sulfate-reducing bacteria in the order Desulfobacterales in sediment and groundwater samples collected nearest the injection gallery where microbially reducible Fe(III) oxides were highly depleted, groundwater sulfate concentrations were low, and increases in acid volatile sulphide (A VS) in the sediment were observed. Further down-gradient, metal reducing conditions were present as indicated by intermediate Fe(II):Fe(total) ratios, lower A VS values, and increased abundance of 16S rDNA sequences belonging to the dissimilatory Fe(III)- and U(VI)-reducing family, Geobacteraceae. Maximal Fe(III) and U(VI) reduction correlated with maximal recovery of Geobacteraceae 16S rDNA sequences in both groundwater and sediment, however the sites at which these maxima occurred were spatially separated within the aquifer. The substantial microbial and geochemical heterogeneity at this site demonstrates that attempts should be made to deliver acetate in a more uniform manner and that closely spaced sampling intervals, horizontally and vertically, in both sediment and groundwater, are necessary in order to obtain a more in-depth understanding of microbial processes and the relative contribution of attached and planktonic populations to in situ uranium bioremediation.

  10. Geomagnetic field observations at a new Antarctic site, within the AIMNet project

    NASA Astrophysics Data System (ADS)

    Lepidi, Stefania; Cafarella, Lili; Santarelli, Lucia; Pietrolungo, Manuela; Urbini, Stefano; Piancatelli, Andrea; Biasini, Fulvio; di Persio, Manuele; Rose, Mike

    2010-05-01

    During the 2007-2008 antarctic campaign, the Italian PNRA installed a Low Power Magnetometer within the framework of the AIMNet (Antarctic International Magnetometer Network) project, proposed and coordinated by BAS. The magnetometer is situated at Talos Dome, around 300 km geographically North-West from Mario Zucchelli Station (MZS), and approximately at the same geomagnetic latitude as MZS. In this work we present a preliminary analysis of the geomagnetic field 1-min data, and a comparison with simultaneous data from different Antarctic stations.

  11. Laboratory and Modeling Evaluations in Support of Field Testing for Desiccation at the Hanford Site

    SciTech Connect

    Truex, Michael J.; Oostrom, Martinus; Freedman, Vicky L.; Strickland, Christopher E.; Wietsma, Thomas W.; Tartakovsky, Guzel D.; Ward, Anderson L.

    2011-02-23

    The Deep Vadose Zone Treatability Test Plan for the Hanford Central Plateau includes testing of the desiccation technology as a potential technology to be used in conjunction with surface infiltration control to limit the flux of technetium and other contaminants in the vadose zone to the groundwater. Laboratory and modeling efforts were conducted to investigate technical uncertainties related to the desiccation process and its impact on contaminant transport. This information is intended to support planning, operation, and interpretation of a field test for desiccation in the Hanford Central Plateau.

  12. Low field magnetocaloric effect and heat capacity of A-site ordered NdBaMn 2O 6 manganite

    NASA Astrophysics Data System (ADS)

    Aliev, A. M.; Gamzatov, A. G.; Kalitka, V. S.; Kaul, A. R.

    2011-12-01

    The magnetocaloric effect (MCE) in the A-site ordered manganite NdBaMn 2O 6 is studied. The MCE in this compound has an anomalous behavior. In low magnetic fields, the abrupt transitions between the direct and inverse magnetocaloric effects are observed. In a relatively strong magnetic field H=11 kOe, the direct and inverse effects are observed only at cooling, while the heating mode reveals only an inverse MCE. The value of the MCE ( -ΔS=0.7 J/kg K and ΔS=1.02 J/kg K for ΔH=11 kOe) does not reach high values, but the proximity of the effects occurring at room temperatures expects the use of both effects in the magnetic cooling technology.

  13. Guidelines and standard procedures for continuous water-quality monitors : site selection, field operation, calibration, record computation, and reporting

    USGS Publications Warehouse

    Wagner, Richard J.; Mattraw, H.C.; Ritz, G.F.; Smith, B.A.

    2000-01-01

    The U.S. Geological Survey uses continuous water-quality monitors to assess variations in the quality of the Nation's surface water. A common system configuration for data collection is the four-parameter water-quality monitoring system, which collects temperature, specific conductance, dissolved oxygen, and pH data, although systems can be configured to measure other properties such as turbidity or chlorophyll. The sensors that are used to measure these water properties require careful field observation, cleaning, and calibration procedures, as well as thorough procedures for the computation and publication of final records. Data from sensors can be used in conjunction with collected samples and chemical analyses to estimate chemical loads. This report provides guidelines for site-selection considerations, sensor test methods, field procedures, error correction, data computation, and review and publication processes. These procedures have evolved over the past three decades, and the process continues to evolve with newer technologies.

  14. Measurement uncertainties in quantifying aeolian mass flux: evidence from wind tunnel and field site data

    PubMed Central

    Keijsers, Joep G.S.; Maroulis, Jerry; Visser, Saskia M.

    2014-01-01

    Aeolian sediment traps are widely used to estimate the total volume of wind-driven sediment transport, but also to study the vertical mass distribution of a saltating sand cloud. The reliability of sediment flux estimations from such measurements are dependent upon the specific configuration of the measurement compartments and the analysis approach used. In this study, we analyse the uncertainty of these measurements by investigating the vertical cumulative distribution and relative sediment flux derived from both wind tunnel and field studies. Vertical flux data was examined using existing data in combination with a newly acquired dataset; comprising meteorological data and sediment fluxes from six different events, using three customized catchers at Ameland beaches in northern Netherlands. Fast-temporal data collected in a wind tunnel shows that the median transport height has a scattered pattern between impact and fluid threshold, that increases linearly with shear velocities above the fluid threshold. For finer sediment, a larger proportion was transported closer to the surface compared to coarser sediment fractions. It was also shown that errors originating from the distribution of sampling compartments, specifically the location of the lowest sediment trap relative to the surface, can be identified using the relative sediment flux. In the field, surface conditions such as surface moisture, surface crusts or frozen surfaces have a more pronounced but localized effect than shear velocity. Uncertainty in aeolian mass flux estimates can be reduced by placing multiple compartments in closer proximity to the surface. PMID:25071984

  15. Establishing seasonal chronicles of actual evapotranspiration under sloping conditions

    NASA Astrophysics Data System (ADS)

    Zitouna Chebbi, R.; Prévot, L.; Jacob, F.; Voltz, M.

    2012-04-01

    Estimation of daily and seasonal actual evapotranspiration (ETa) is strongly needed for hydrological and agricultural purposes. Although the eddy covariance method is well suited for such estimation of land surface fluxes, this method suffers from limitations when establishing long time series. Missing data are often encountered, resulting from bad meteorological conditions, rejection by quality control tests, power failures… Numerous gap fill techniques have been proposed in the literature but there applicability in sloping conditions is not well known. In order to estimate ETa over long periods (agricultural cycle) on crops cultivated in sloping areas, a pluri-annual experiment was conducted in the Kamech catchment, located in North-eastern Tunisia. This Mediterranean site is characterized by a large heterogeneity in topography, soils and crops. Land surface fluxes were measured using eddy covariance systems. Measurements were collected on the two opposite sides of the Kamech V-shaped catchment, within small fields having slopes steeper than 5%. During three different years, four crops were studied: durum wheat, oat, fava bean and pasture. The topography of the catchment and the wind regime induced upslope and downslope flows over the study fields. In this study, we showed that gap filling of the turbulent fluxes (sensible and latent heat) can be obtained through linear regressions against net radiation. To account for the effect of the topography, linear regressions were calibrated by distinguishing upslope and downslope flows. This significantly improved the quality of the reconstructed data over 30 minute intervals. This gap filling technique also improved the energy balance closure at the daily time scale. As a result, seasonal chronicles of daily ETa throughout the growth cycle of the study crops in the Kamech watershed were established, thus providing useful information about the water use of annual crops in a semi-arid rainfed and hilly area.

  16. Integrated metagenomics and field measurements of polygon features at the NGEE-Arctic Barrow site

    NASA Astrophysics Data System (ADS)

    Tas, N.; Wu, Y.; Smith, L. J.; Ulrich, C.; Kneafsey, T. J.; Torn, M. S.; Hubbard, S. S.; Wullschleger, S. D.; Jansson, J.

    2013-12-01

    Arctic soils contain an estimated 12-42% of terrestrial carbon, most of which is sequestered in permafrost. High latitudes have experienced the greatest regional warming in recent decades and observations suggest that permafrost degradation is now commonly observed in the region. With increasing global temperatures, permafrost soils are becoming a potential source of greenhouse gas (GHG) emissions. Because of widespread permafrost thaw much of the soil organic matter may be available for rapid mineralization by microorganisms in the soil. Yet little is known about the vulnerability of permafrost and the potential response of soil microorganisms to availability of new carbon sources. On the Alaskan North Slope the collapse and rise of soil due to formation of ice wedges and permafrost thaw create distinct features called polygons. As part of the U.S. Department of Energy (DOE) Next Generation Ecosystem Experiment (NGEE) in the Arctic, we aimed to determine the distribution of microbial populations across a range of polygon features and to correlate the microbial data to GHG flux data. To determine the microbial community distribution and metabolic potential, we collected seasonally thawed active layer soil samples along two polygon transects (Site 0 and AB), including high-centered, transitional and low-centered polygons. Illumina HiSeq technology was used to sequence 16SrRNA genes and metagenomes from these active layer soils. The sequence data was correlated to GHG flux measurements and to environmental data from the site, including geophysical and geochemical soil characteristics. Both the microbial communities and the flux measurements varied along the polygon transect. Each polygon had a distinct microbial community structure; however, these microbial communities shared many metabolic capabilities. For example, many genes involved in degradation of chitin could be found all three polygons. Functional genes involved in methanogenesis and CH4-flux measurements

  17. Improved Detection of Microearthquakes in Geothermal Areas - Applying Empirical Matched Field Processing to Traditional and EGS sites

    NASA Astrophysics Data System (ADS)

    Templeton, D. C.; Wang, J.; Harris, D. B.

    2012-12-01

    The aim of this project is to increase the amount of information that can be extracted from seismic data collected in EGS or traditional geothermal areas. To accomplish our objective, we develop a seismic imaging technique that can map seismicity from discrete microearthquake sources using the Matched Field Processing (MFP) method. We use data from the Salton Sea geothermal field available from the Southern California Earthquake Data Center. Data between November 2009 and December 2010 was downloaded off the web and 231 high-quality master events were identified from the online catalog. This time period included two robust earthquake swarms. We created matched field steering vector calibrations for 7 three-component stations within the Salton Sea Geothermal Field. The official earthquake catalog identified 1536 events. When we applied the empirical MFP technique to the same data, we identified 5357 events. We then compare the results from this traditional geothermal area with results obtained from an Engineered Geothermal System (EGS) site. Finally, we compare the number of events in the improved earthquake catalogs with available fluid injection data. This work performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344.

  18. Field and Numerical Modeling Study of Reductive Bioimmobilization of Cr (VI) in Groundwater at Hanford 100-H Site

    NASA Astrophysics Data System (ADS)

    Hazen, T. C.; Sonnenthal, E. L.; Mukhopadhyay, S.; Steefel, C. I.; Long, P. E.; Faybishenko, B.

    2009-12-01

    The 2004-2008 field experiment at the Hanford 100-H Site showed that a single injection of the hydrogen release compound (HRC)—a mixture of slow release glycerol polylactate, fast disassociating lactic acid, and glycerol into groundwater— stimulated an increase in biomass and a depletion of terminal electron acceptors, resulting in a significant decrease in soluble Cr (VI). The Cr (VI) concentration remained below the background concentration in the downgradient pumping/monitoring well, and below the detection limit in the injection well, for more than 3 years after the initial HRC injection in 2004. Reaction-transport modeling of the field experiment was performed to elucidate reaction pathways and rates of biogeochemical processes governing Cr (VI) bioimmobilization. Field observation data were used to develop a 3-D hydraulic and reaction-transport-isotopic model, simulated using the TOUGHREACT code. This model was used to assess the degradation kinetics of the HRC, the effects of lactate and acetate-induced bioreduction of Cr and Fe, and the effects on Cr and Sr isotopic compositions in the fluids and mineral phases (calcite dissolution in the acidic plume and precipitation at the fringes). The 2008 experiment involved reinjection of HRC into the same zones as the earlier injection and likely resulted in dissolution of previously precipitated Cr (Fe) hydroxides and additional calcite dissolution in sediments outside of the wellbore. Detailed results of the integrated field and modeling study will be presented.

  19. Assessing field-scale migration of radionuclides at the Nevada Test Site: "mobile" species.

    PubMed

    Hu, Q H; Rose, T P; Zavarin, M; Smith, D K; Moran, J E; Zhao, P H

    2008-10-01

    Many long-lived radionuclides are present in groundwater at the Nevada Test Site (NTS) as a result of 828 underground nuclear weapons tests conducted between 1951 and 1992. In conjunction with a comprehensive geochemical review of radionuclides (3H, 14C, 36Cl, 99Tc and 129I) that are presumably mobile in the subsurface, we synthesized a body of radionuclide activity data measured from groundwater samples collected at 18 monitoring wells, to qualitatively assess their migration at the NTS over distances of hundreds of meters and over timescales of decades. Tritium and 36Cl showed little evidence of retardation, while the transport of 14C may have been retarded by its isotopic exchange with carbonate minerals in the aquifer. Observed local reducing conditions (either natural or test-induced) will impact the mobility of certain redox-sensitive radionuclides (especially 99Tc) that were otherwise soluble and readily transported under oxidizing conditions. Conversely, strongly oxidizing conditions may impact the mobility of 129I which is mobile under reducing conditions. The effect of iodine speciation on its transport deserves further attention. Indication of delayed transport of some "mobile" radionuclides (especially 99Tc) in the groundwater at the NTS suggested the importance of redox conditions of the natural system in controlling the fate and transport of radionuclides, which has implications in the enhanced performance of the potential Yucca Mountain repository, located adjacent to the NTS, to store high-level nuclear wastes as well as management of radionuclide contamination in legacy nuclear operations facilities.

  20. San Ignacio (La Tembladera) geothermal site, Departamento de Francisco Morazan, Honduras, Central America: Geological field report

    SciTech Connect

    Aldrich, M.J.; Eppler, D.; Heiken, G.; Flores, W.; Ramos, N.; Ritchie, A.

    1987-06-01

    The San Ignacio (La Tembladera) geothermal site is located on the north side of the Siria Valley, Departamento de Francisco Morazan, near the village of Barrosa. Hot springs are located along a northwest-trending fault scarp at the edge of the valley and along north-trending faults that cross the scarp. The rocks in the area are primarily Paleozoic metamorphic rocks, overlain by patches of Tertiary Padre Miguel Group tuffs and alluvial deposits. Movement probably occurred along several faults during latest Tertiary and possibly early Quaternary times. Four spring areas were mapped. Area 1, the largest, is associated with a sinter mound and consists of 40 spring groups. About half of the springs, aligned along a north-south trend, are boiling. Area 2 is a small sinter mound with several seeps. Area 3 consists of a group of hot and boiling springs aligned along a north-trending fault. The springs rise through fractured schists and a thin cover of alluvium. Area 4 is located at the intersection of several faults and includes one of the largest boiling springs in the area.

  1. Los Alamos Mobile Radiological Laboratory fielded during post shot drilling operations at the Nevada Test Site

    SciTech Connect

    Carpenter, J.

    1993-12-31

    The Los Alamos National Laboratory Health Physics group fields a 10 x 50 semi trailer housing radiation detection systems during each post shot drilling operation. A discussion of the post shot drilling equipment, procedures, and radiological concerns are included together with a description of the radiation detection systems installed in the trailer. Each detection system is integrated with the drilling and {open_quotes}containment{close_quotes} features to provide continuous radiological monitoring of a Continuous Air Monitoring (CAM) on the rig floor, radiological gases in the cellar and annulus of the blow out preventer (BOP), estimate of activity released through a breach of the containment system, and direct radiological monitoring of the fluid returns during the drilling process. The containment features of the drilling operation and the detection systems in the trailer are calibrated annually as an integrated system by releasing Xenon-133 gas in the cellar and tracking it through the system.

  2. Evaluation of Human vs. Teleoperated Robotic Performance in Field Geology Tasks at a Mars Analog Site

    NASA Technical Reports Server (NTRS)

    Glass, B.; Briggs, G.

    2003-01-01

    Exploration mission designers and planners have costing models used to assess the affordability of given missions - but very little data exists on the relative science return produced by different ways of exploring a given region. Doing cost-benefit analyses for future missions requires a way to compare the relative field science productivity of spacesuited humans vs. virtual presence/teleoperation from a nearby habitat or orbital station, vs. traditional terrestrial-controlled rover operations. The goal of this study was to define science-return metrics for comparing human and robotic fieldwork, and then obtain quantifiable science-return performance comparisons between teleoperated rovers and spacesuited humans. Test runs with a simulated 2015-class rover and with spacesuited geologists were conducted at Haughton Crater in the Canadian Arctic in July 2002. Early results imply that humans will be 1-2 orders of magnitude more productive per unit time in exploration than future terrestrially-controlled robots.

  3. Efficacy of ovitrap colors and patterns for attracting Aedes albopictus at suburban field sites in north-central Florida.

    PubMed

    Hoel, David F; Obenauer, Peter J; Clark, Marah; Smith, Richard; Hughes, Tony H; Larson, Ryan T; Diclaros, Joseph W; Allan, Sandra A

    2011-09-01

    We sought to visually enhance the attractiveness of a standard black ovitrap routinely used in surveillance of the Asian tiger mosquito, Aedes albopictus, and now being used as lethal ovitraps in Ae. aegypti dengue control programs. Black plastic drinking cups (ovitraps) were visually altered to offer field populations of gravid female Ae. albopictus 6 different oviposition site choices. Trials were conducted at 3 field locations in Gainesville, Orange Park, and Jacksonville, FL, during July-August 2009. A black glossy cup served as the control and was tested against 5 cup choices consisting of white, blue, orange, or black-and-white contrasting patterns (checkered or vertically striped). Means (SE) of eggs collected over 6 wk for each choice were: black 122.53 (9.63) > blue 116.74 (10.74) > checkered 101.84 (9.53) > orange 97.15 (7.95) > striped 84.62 (8.17) > white 81.84 (8.74). Black ovitraps outperformed competing colored and contrasting patterned ovicups with respect to choice from gravid Ae. albopictus seeking artificial oviposition sites. PMID:22017088

  4. Field-Integrated Studies of Long-Term Sustainability of Chromium Bioreduction at Hanford 100H Site

    SciTech Connect

    Philip E. Long

    2006-06-01

    The objectives of the project are to investigate coupled hydraulic, geochemical, and microbial conditions, and to determine the critical biogeochemical parameters necessary to maximize the extent of Cr(VI) bioreduction and minimize Cr(III) reoxidation in groundwater. Specific goals of the project are as follows: (1) Field testing and monitoring of Cr(VI) bioreduction in ground water and its transformation into insoluble species of Cr(III) at the Hanford 100H site, to develop the optimal strategy of water sampling for chemical, microbial, stable isotope analyses, and noninvasive geophysical monitoring; (2) Bench-scale flow and transport investigations using columns of undisturbed sediments to obtain diffusion and kinetic parameters needed for the development of a numerical model, predictions of Cr(VI) bioreduction, and potential of Cr(III) reoxidation; and (3) Development of a multiphase, multi-component 3D reactive transport model and a code, TOUGHREACT-BIO, to predict coupled biogeochemical-hydrological processes associated with bioremediation, and to calibrate and validate the developed code based on the results of bench-scale and field-scale Cr(VI) biostimulation experiments in ground water at the Hanford Site.

  5. SIGNAL : Water vapour flux variability and local wind field investigations within five differently managed agroforestry sites across Germany

    NASA Astrophysics Data System (ADS)

    Markwitz, Christian; Siebicke, Lukas; Knohl, Alexander

    2016-04-01

    Optimising soil water uptake and ground water consumption in mono-specific agricultural systems plays an important role for sustainable land management. By including tree alleys into the agricultural landscape, called agroforestry (AF), the wind flow is modified leading to a presumably favourable microclimate behind the tree alleys. We expect that this zone is characterized by increased air temperature and atmospheric water vapour content, compared to mono-specific fields. This would extend the growing season and increase the yield production behind the tree alleys. Within the SIGNAL (Sustainable Intensification of Agriculture through Agroforestry) project the evapotranspiration (ET) variability and the local wind field of agroforestry sites compared to mono-specific agricultural systems is investigated. Our study is based on the comparison of five differently managed agroforestry sites across Germany. All site feature one agroforestry plot and one reference plot, which represents a mono-specific cropped system. Each plot is equipped with an eddy-covariance tower, including a high frequency 3D SONIC anemometer and instruments gathering standard meteorological parameter as pressure, temperature, relative humidity, precipitation, ground heat flux, net- and global radiation. The Surface Energy Budget (SEB) method will be used to calculate evapotranspiration QE as QE = - QN - QH - QG - Res by measuring the sensible heat flux, QH, with the eddy covariance method, the radiation balance, QN and the ground heat flux, QG. QH and QN will be measured continuously long-term. We will quantify site specific energy balance non-closure, Res, by temporarily measuring QE, using eddy covariance and a roving tower and then solving the SEB equation for Res. The short term Res will be used to then continuously derive QE from the SEB method. We will compare measured evapotranspiration rates from the SEB method to modelled evapotranspiration of the agroforestry systems through upscaling

  6. Effect of uncertain hydraulic conductivity on the fate and transport of BTEX compounds at a field site

    SciTech Connect

    Lu, Guoping; Zheng, Chunmiao; Wolfsberg, Andrew

    2002-01-05

    A Monte Carlo analysis was conducted to investigate the effect of uncertain hydraulic conductivity on the fate and transport of BTEX compounds (benzene, toluene, ethyl benzene, and xylene) at a field site on Hill Air Force Base, Utah. Microbially mediated BTEX degradation has occurred at the site through multiple terminal electron-accepting processes, including aerobic respiration, denitrification, Fe(III) reduction, sulfate reduction, and methanogenesis degradation. Multiple realizations of the hydraulic conductivity field were generated and substituted into a multispecies reactive transport model developed and calibrated for the Hill AFB site in a previous study. Simulation results show that the calculated total BTEX masses (released from a constant-concentration source) that remain in the aquifer at the end of the simulation period statistically follow a lognormal distribution. In the first analysis (base case), the calculated total BTEX mass varies from a minimum of 12% less and a maximum of 60% more than that of the previously calibrated model. This suggests that the uncertainty in hydraulic conductivity can lead to significant uncertainties in modeling the fate and transport of BTEX. Geometric analyses of calculated plume configurations show that a higher BTEX mass is associated with wider lateral spreading, while a lower mass is associated with longer longitudinal extension. More BTEX mass in the aquifer causes either a large depletion of dissolved oxygen (DO) and NO{sub 3}{sup -}, or a large depletion of DO and a large production of Fe{sup 2+}, with moderately depleted NO{sub 3}{sup -}. In an additional analysis, the effect of varying degrees of aquifer heterogeneity and associated uncertainty is examined by considering hydraulic conductivity with different variances and correlation lengths. An increase in variance leads to a higher average BTEX mass in the aquifer, while an increase in correlation length results in a lower average. This observation is

  7. Field study of the composition of greywater and comparison of microbiological indicators of water quality in on-site systems.

    PubMed

    Leonard, Margaret; Gilpin, Brent; Robson, Beth; Wall, Katrina

    2016-08-01

    Thirty on-site greywater systems were sampled to determine greywater characteristics and practices in the field. Kitchen greywater was present at eight sites and urine was included at seven sites. These non-traditional sources resulted in significantly higher concentrations of enterococci and 5-day biochemical oxygen demand (BOD5) in greywater. Even with the removal of these sources, the concentrations of microbial indicators indicated high levels of contamination could occur across all greywater sources, including "light" greywater. Using multiple microbial indicators showed that all samples had the potential for faecal contamination. Bacteroidales markers were confirmed in treated greywater and in each greywater source, highlighting the potential for human faecal contamination. Although Escherichia coli was absent in treated greywater recycled to the house, other microbial indicators were present; hence, caution is required in using E. coli concentrations as the sole indicator of microbiological water quality. High BOD5 or total suspended solid concentrations exceeded the levels recommended for effective disinfection. Subsurface irrigation, which is assumed to provide a five-log reduction in exposure, is a suitable reuse option for non-disinfected greywater. Only half the occupants had a good understanding of their greywater systems and 25 % of systems were poorly maintained. Elevated microbial indicator contamination of greywater sludge is a potential hazard during maintenance. PMID:27435622

  8. Field study of the composition of greywater and comparison of microbiological indicators of water quality in on-site systems.

    PubMed

    Leonard, Margaret; Gilpin, Brent; Robson, Beth; Wall, Katrina

    2016-08-01

    Thirty on-site greywater systems were sampled to determine greywater characteristics and practices in the field. Kitchen greywater was present at eight sites and urine was included at seven sites. These non-traditional sources resulted in significantly higher concentrations of enterococci and 5-day biochemical oxygen demand (BOD5) in greywater. Even with the removal of these sources, the concentrations of microbial indicators indicated high levels of contamination could occur across all greywater sources, including "light" greywater. Using multiple microbial indicators showed that all samples had the potential for faecal contamination. Bacteroidales markers were confirmed in treated greywater and in each greywater source, highlighting the potential for human faecal contamination. Although Escherichia coli was absent in treated greywater recycled to the house, other microbial indicators were present; hence, caution is required in using E. coli concentrations as the sole indicator of microbiological water quality. High BOD5 or total suspended solid concentrations exceeded the levels recommended for effective disinfection. Subsurface irrigation, which is assumed to provide a five-log reduction in exposure, is a suitable reuse option for non-disinfected greywater. Only half the occupants had a good understanding of their greywater systems and 25 % of systems were poorly maintained. Elevated microbial indicator contamination of greywater sludge is a potential hazard during maintenance.

  9. Field-mapping and petrographic analysis of volcanoes surrounding the Lake Natron Homo sapiens footprint site, northern Tanzania

    NASA Astrophysics Data System (ADS)

    Hewitt, S. M.; Zimmer, B.; Liutkus, C.; Carmichael, S. K.; McGinnis, K.

    2010-12-01

    The Lake Natron Homo sapiens footprint site is located in northern Tanzania along the East African Rift escarpment. The site is positioned south of Lake Natron within an ephemeral channel of the Engare Sero River. The hominid footprints are preserved in a tuff, which originated from one of the volcanic centers surrounding the site. Two large volcanoes in the surrounding region, including the active carbonatite producing Oldoinyo L’engai and the now extinct Kerimasi are possible sources. This area also contains over 30 smaller tuff cones and tuff rings that have been poorly mapped and not analyzed in detail. The site is significant as it is the oldest modern human trackway in East Africa and one of the largest collections of hominid footprints in the world. Determining the source of the footprinted volcanic ash requires detailed field mapping, and both petrographic and geochemical analyses. Extensive field-mapping of the region revealed multiple regional beds that stratigraphically overlay the footprinted layer. Age dating as well as geochemical analysis is being conducted to relate these beds to the footprinted layer. Field-mapping showed that the footprinted tuff is over 35 cm thick, suggesting a large, sustained eruption. The bulk of the tuff cones examined in the field visibly varied in composition to the footprinted tuff and, based on proximity to the footprint site, are too small to produce the requisite volume of ash. Field analysis of samples collected from Oldoinyo L’engai reveal the most similar mineral assemblages to the footprinted layer, and the large volcano provides a source substantial enough to create a thick ash bed 10 km north of the summit. Preliminary research reveals that the footprinted tuff is a phonolite, characterized by silica depletion and the presence of sanidine, augite, and annite with interstitial calcite. XRD analysis of samples collected from Oldoinyo L’engai reveal a nepheline-rich phonolite with zeolites (ie. phillipsite

  10. Geology of the platanares geothermal site, Departamento de Copan, Honduras, Central America. Field report

    SciTech Connect

    Heiken, G.; Eppler, D.; Wohletz, K.; Flores, W.; Ramos, N.; Ritchie, A.

    1986-05-01

    Platanares is located 16 km west of Santa Rosa de Copan, Honduras, along the Quebrada del Agua Caliente. The thermal manifestations are along faults in tuffs, tuffaceous sedimentary rocks, and lavas of the Padre Miguel Group. These tuffs are silicified near the faults, are fractured, and may provide the fracture permeability necessary for the hydrothermal system. Tuffs are overlain by a wedge of terrace gravels up to 60 m thick. Quaternary conglomerates of the Quebrada del Agua Caliente are cemented by silica sinter. The Platanares area contains numerous faults, all of which appear to be extensional. There are four groups of faults (N80/sup 0/E to N70/sup 0/W, N30/sup 0/ to 60/sup 0/W, N40/sup 0/ to 65/sup 0/E, and N00/sup 0/ to 05/sup 0/W). All hot springs at this site are located along faults that trend mostly northwest and north. Twenty-eight spring groups were described over an area of 0.2 km/sup 2/; half were boiling. Based on surface temperatures and flow rates, between 0.7 and 1.0 MW thermal energy is estimated for the area. The increased temperature of the stream flowing through the thermal area indicates that several megawatts of thermal energy are being added to the stream. We recommend that a dipole-dipole resistivity line be run along the Quebrada del Agua Caliente to identify zones of fracture permeability associated with buried faults and hot water reservoirs within those fault zones. A thermal gradient corehole should be drilled at Platanares to test temperatures, lithologies, and permeability of the hydrothermal system.

  11. Improving time-lapse seismic repeatability: CO2CRC Otway site permanent geophone array field trials

    NASA Astrophysics Data System (ADS)

    Pevzner, Roman; Dupuis, Christian; Shulakova, Valeriya; Urosevic, Milovan; Lumley, David

    2013-04-01

    The proposed Stage 2C of the CO2CRC Otway project involves injection of a small amount (around 15,000 tonnes) of CO2/CH4 gas mixture into saline acquifer (Paaratte formation) at the depth of ~1.5 km. The seismic time-lapse signal will depend largely on the formation properties and the injection scenario, but is likely to be relatively weak. In order to improve time-lapse seismic monitoring capabilities by decreasing the noise level, a buried receiver arrays can be used. A small-scale trial of such an array was conducted at Otway site in June 2012. A set of 25 geophones was installed in 3 m deep boreholes in parallel to the same number of surface geophones. In addition, four geophones were placed into boreholes of 1 to 12 m depth. In order to assess the gain in the signal-to-noise ratio and repeatability, both active and passive seismic surveys were carried out. The surveys were conducted in relatively poor weather conditions, with rain, strong wind and thunderstorms increasing the noise level. We found that noise level for buried geophones is on average 20 dB lower compared to the surface ones. Furthermore, the combination of active and passive experiments has allowed us to perform a detailed classification of various noise sources. Acknowledgement The authors acknowledge the funding provided by the Australian government through its CRC program to support this CO2CRC research project. We also acknowledge the CO2CRC's corporate sponsors and the financial assistance provided through Australian National Low Emissions Coal Research and Development (ANLEC R&D). ANLEC R&D is supported by Australian Coal Association Low Emissions Technology Limited and the Australian Government through the Clean Energy Initiative.

  12. Great Kobuk Sand Dunes, Alaska: A Terrestrial Analog Site for Polar, Topographically Confined Martian Dune Fields

    NASA Astrophysics Data System (ADS)

    Dinwiddie, C. L.; Hooper, D. M.; Michaels, T. I.; McGinnis, R. N.; Stillman, D.; Bjella, K.; Stothoff, S.; Walter, G. R.; Necsoiu, M.; Grimm, R. E.

    2010-12-01

    Martian dune systems belong to two broad categories: (i) the sprawling north polar erg, rich in and immobilized by seasonal and perennial volatiles; and (ii) isolated low- to high-latitude dune fields confined by topography. While modern dune migration on Mars is nearly imperceptibly slow, recent studies are producing robust evidence for aeolian activity, including bedform modification. Cold-climate terrestrial dunes containing volatile reservoirs provide an important analog to Martian polar dunes because permafrost and seasonal cycles of CO2 and H2O frost mantling are thought to partially decouple Martian polar dunes from atmospheric forcing. The 67°N latitude, 62 km2 Great Kobuk Sand Dunes (GKSD) are a terrestrial analog for polar, intercrater dune fields on Mars. Formative winds affected by complex topography and the presence of volatiles and intercalated snow within the GKSD have direct analogy to factors that impede migration of Martian polar dunes. This system offers the opportunity to study cold-climate, noncoastal, topographically constrained, climbing and reversing barchanoid, transverse, longitudinal, and star dunes. The Kobuk Valley climate is subarctic and semiarid with long, cold winters and brief, warm summers. Niveoaeolian sedimentation occurs within west-facing lee slope catchments. In March 2010, we found the seasonally frozen layer to range in thickness from 1.5 to 4.0 m, and no evidence for shallow permafrost. Instead, using GPR and boreholes, we found a system-wide groundwater aquifer that nearly parallels topography and cuts across steeply dipping bedforms. GPR cannot uniquely detect ice and water; however, a similar analysis of rover-based GPR might be used to detect volatiles in Martian dunes. The perennial volatile reservoir is liquid because of mean annual air temperature, intense solar heating before, during, and after 38 days of continuous summer daylight, high dry sand thermal conductivity, higher wet sand thermal conductivity

  13. Field measures show methanotroph sensitivity to soil moisture follows precipitation regime of the grassland sites across the US Great Plains

    NASA Astrophysics Data System (ADS)

    Koyama, A.; Webb, C. T.; Johnson, N. G.; Brewer, P. E.; von Fischer, J. C.

    2015-12-01

    Methane uptake rates are known to have temporal variation in response to changing soil moisture levels. However, the relative importance of soil diffusivity vs. methanotroph physiology has not been disentangled to date. Testing methanotroph physiology in the laboratory can lead to misleading results due to changes in the fine-scale habitat where methanotrophs reside. To assay the soil moisture sensitivity of methanotrophs under field conditions, we studied 22 field plots scattered across eight Great Plains grassland sites that differed in precipitation regime and soil moisture, making ca. bi-weekly measures during the growing seasons over three years. Quantification of methanotroph activity was achieved from chamber-based measures of methane uptake coincident with SF6-derived soil diffusivity, and interpretation in a reaction-diffusion model. At each plot, we also measured soil water content (SWC), soil temperature and inorganic nitrogen (N) contents. We also assessed methanotroph community composition via 454 sequencing of the pmoA gene. Statistical analyses showed that methanotroph activity had a parabolic response with SWC (concave down), and significant differences in the shape of this response among sites. Moreover, we found that the SWC at peak methanotroph activity was strongly correlated with mean annual precipitation (MAP) of the site. The sequence data revealed distinct composition patterns, with structure that was associated with variation in MAP and soil texture. These results suggest that local precipitation regime shapes methanotroph community composition, which in turn lead to unique sensitivity of methane uptake rates with soil moisture. Our findings suggest that methanotroph activity may be more accurately modeled when the biological and environmental responses are explicitly described.

  14. Experimental and Numerical Study of Wind and Turbulence in a Near-Field Dispersion Campaign at an Inhomogeneous Site

    NASA Astrophysics Data System (ADS)

    Wei, Xiao; Dupont, Eric; Gilbert, Eric; Musson-Genon, Luc; Carissimo, Bertrand

    2016-09-01

    We present a detailed experimental and numerical study of the local flow field for a pollutant dispersion experimental program conducted at SIRTA (Site Instrumental de Recherche par Télédétection Atmosphérique), a complex and intensively instrumented site in a southern suburb of Paris. Global analysis of continuous measurements over 2 years highlights the impact of terrain heterogeneity on wind and turbulence. It shows that the forest to the north of the experimental field induces strong directional shear and wind deceleration below the forest canopy height. This directional shear is stronger with decreasing height and decreasing distance from the forest edge. Numerical simulations are carried out using Code_Saturne, a computational fluid dynamics code, in Reynolds-averaged Navier-Stokes mode with a standard k{-}ɛ closure and a canopy model, in neutral and stable stratifications. These simulations are shown to reproduce globally well the characteristics of the mean flow, especially the directional wind shear in northeasterly and northwesterly cases and the turbulent kinetic energy increase induced by the forest. However, they slightly underestimate wind speed and the directional shear of the flow below the forest canopy height. Sensitivity studies are performed to investigate the influence of leaf area density, inlet stability condition, and roughness length. These studies show that the typical features of the canopy flow become more pronounced as canopy density increases. Performance statistics indicate that the impact of the forest and adequate inlet profiles are the most important factors in the accurate reproduction of flow at the site, especially under stable stratification.

  15. Evaluating the summer night sky brightness at a research field site on Lake Stechlin in northeastern Germany

    NASA Astrophysics Data System (ADS)

    Jechow, Andreas; Hölker, Franz; Kolláth, Zoltán; Gessner, Mark O.; Kyba, Christopher C. M.

    2016-09-01

    We report luminance measurements of the summer night sky at a field site on a freshwater lake in northeastern Germany (Lake Stechlin) to evaluate the amount of artificial skyglow from nearby and distant towns in the context of a planned study on light pollution. The site is located about 70 km north of Berlin in a rural area possibly belonging to one of the darkest regions in Germany. Continuous monitoring of the zenith sky luminance between June and September 2015 was conducted utilizing a Sky Quality Meter. With this device, typical values for clear nights in the range of 21.5-21.7 magSQM/arcsec2 were measured, which is on the order of the natural sky brightness during starry nights. On overcast nights, values down to 22.84 magSQM/arcsec2 were obtained, which is about one third as bright as on clear nights. The luminance measured on clear nights as well as the darkening with the presence of clouds indicates that there is very little influence of artificial skyglow on the zenith sky brightness at this location. Furthermore, fish-eye lens sky imaging luminance photometry was performed with a digital single-lens reflex camera on a clear night in the absence of moonlight. The photographs unravel several distant towns as possible sources of light pollution on the horizon. However, the low level of artificial skyglow makes the field site at Lake Stechlin an excellent location to study the effects of skyglow on a lake ecosystem in a controlled fashion.

  16. Sensitivity analysis of tracer transport in variably saturated soils at USDA-ARS OPE3 field site

    NASA Astrophysics Data System (ADS)

    Guber, A.; Pan, F.; Pachepsky, Y. A.; Yakirevich, A.; Gish, T.; Nicholson, T. J.; Cady, R. E.

    2010-12-01

    The objective of this study was to assess the effects of uncertainties in hydrologic and geochemical parameters on the results of simulations of the tracer transport in variably saturated soils at the USDA-ARS OPE3 field site. A tracer experiment with a pulse of KCL solution applied to an irrigation plot was implemented to measure the chloride concentration at three sampling depths of 12 observations wells at the OPE3 site. The soil material spatial distribution was obtained from soil cores. The hydraulic conductivity for each material was estimated based on the soil pore size distribution using the ROSETTA software. Saturated and residual soil moisture contents, and van Genuchten parameters were obtained by fitting the van Genuchten model to the measured water retention curves. A three-dimension flow and transport model was set up to simulate the flow and chloride transport for the tracer experiment at the OPE3 site. Sensitivity analysis was conducted for three parameters (hydraulic conductivity, longitudinal and transverse dispersivity) through variations of these parameter values by one standard deviation from the base-case values at each of eight soil materials. The parameter variations resulted in 256 parameter sets. Sensitivity index of each parameter for each material was calculated based on the 256 parameter-set modeling results with regard to groundwater level, peak tracer concentration, and peak travel time. The importance of parameter variations on the tracer transport at the OPE3 site was evaluated through the values of sensitivity indices. The results showed that the variations in hydraulic conductivity at sandy loam soils caused larger uncertainty of tracer transport than the ones at other soil materials. Stochastic simulations of the spatial distribution of sandy loam subsurface structural units can contribute to the evaluation of possible improvements in monitoring designs. The outcome of this study can provide the information for the future data

  17. Site Environmental Report for Calendar Year 2013. DOE Operations at The Boeing Company, Santa Susana Field Laboratory, Area IV

    SciTech Connect

    2014-06-30

    This Annual Site Environmental Report (ASER) for 2013 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of the Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, operation and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward environmental restoration and decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2013 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling. Due to the suspension of D&D activities in Area IV, no effluents were released into the atmosphere during 2013. Therefore, the potential radiation dose to the general public through airborne release was zero. Similarly, the radiation dose to an offsite member of the public (maximally exposed individual) due to direct radiation from SSFL is indistinguishable from background. All radioactive wastes are processed for disposal at DOE disposal sites and/or other licensed sites approved by DOE for radioactive waste

  18. Use of radium isotopes to determine the age and origin of radioactive barite at oil-field production sites

    USGS Publications Warehouse

    Zielinski, R.A.; Otton, J.K.; Budahn, J.R.

    2001-01-01

    Radium-bearing barite (radiobarite) is a common constituent of scale and sludge deposits that form in oil-field production equipment. The barite forms as a precipitate from radium-bearing, saline formation water that is pumped to the surface along with oil. Radioactivity levels in some oil-field equipment and in soils contaminated by scale and sludge can be sufficiently high to pose a potential health threat. Accurate determinations of radium isotopes (226Ra+228Ra) in soils are required to establish the level of soil contamination and the volume of soil that may exceed regulatory limits for total radium content. In this study the radium isotopic data are used to provide estimates of the age of formation of the radiobarite contaminant. Age estimates require that highly insoluble radiobarite approximates a chemically closed system from the time of its formation. Age estimates are based on the decay of short-lived 228Ra (half-life=5.76 years) compared to 226Ra (half-life=1600 years). Present activity ratios of 228Ra/226Ra in radiobarite-rich scale or highly contaminated soil are compared to initial ratios at the time of radiobarite precipitation. Initial ratios are estimated by measurements of saline water or recent barite precipitates at the site or by considering a range of probable initial ratios based on reported values in modern oil-field brines. At sites that contain two distinct radiobarite sources of different age, the soils containing mixtures of sources can be identified, and mixing proportions quantified using radium concentration and isotopic data. These uses of radium isotope data provide more description of contamination history and can possibly address liability issues. Copyright ?? 2000 .

  19. Characterization of the inorganic aerosol in Barcelona site during DAURE 2009 field campaigns

    NASA Astrophysics Data System (ADS)

    Plaza, Javier; Gómez-Moreno, Francisco J.; Aránzazu Revuelta, M.; Coz, Esther; Moreno, Natalia; Pujadas, Manuel; Artíñano, Begoña.

    2010-05-01

    Inorganic compounds account for a significant mass of the ambient aerosol. However this contribution varies with time and aerosol size fraction, depending on the influence of source emissions and ambient conditions, which can be relevant in the formation processes of secondary species. Time series of particulate nitrate, 10 m time resolution, have been obtained during the February-March and July 2009 DAURE (Determination of the sources of atmospheric Aerosols in Urban and Rural Environments in the western Mediterranean) field campaigns in the urban area of Barcelona by means of an R&P8400N monitor. Meteorological conditions during these periods were relevant for the photochemical formation and accumulation of secondary species. Ambient concentrations were higher in winter, specially coinciding with development of atmospheric stagnant episodes that enhanced the accumulation of pollutants including particulate nitrate that reached concentrations of 25 µgm-3 in some occasions, day or night, under these conditions. High humidity periods favored in occasions the formation of nitrates at submicronic scale. Variations in wind direction resulted in transport of particulate nitrate from near emission areas. Size segregated aerosol was sampled during the winter campaign with a micro-orifice uniform deposit impactor (MOUDI) using eleven size stages with aluminum substrates and a quartz fiber backup filter. Samples were collected twice per day for day/night periods. The first sampling period tried to collect secondary aerosol as it started after the early morning emission period. The second sample collected the night aerosol and the emission period. Soluble ions (sulfate, nitrate, ammonium and calcium) were later analyzed by IC. The nitrate mass was concentrated in two modes, the accumulation one around 0.75 µm and the coarse one around 3.90 µm. The sulfate and ammonium masses were concentrated in the accumulation mode, around 0.50 µm, although a small peak close to 5 µm

  20. Indirect measurements of field-scale hydraulic conductivity of waste from two landfill sites.

    PubMed

    Fleming, I R

    2011-12-01

    Management and prediction of the movement and distribution of fluids in large landfills is important for various reasons. Bioreactor landfill technology shows promise, but in arid or semi-arid regions, the natural content of landfilled waste may be low, thus requiring addition of significant volumes of water. In more humid locations, landfills can become saturated, flooding gas collection systems and causing sideslope leachate seeps or other undesirable occurrences. This paper compares results from two different approaches to monitoring water in waste. At the Brock West Landfill in eastern Canada, positive pore pressures were measured at various depths in saturated waste. The downward seepage flux through the waste is known, thus the vertical saturated hydraulic conductivity of the waste at this landfill was determined to be 3 × 10(-7)cm/s. By comparison, the Spadina Landfill in western Canada is predominantly unsaturated. The infiltration of moisture into the waste was measured using moisture sensors installed in boreholes which determined arrival time for moisture fronts resulting from major precipitation events as well as longer-term change in moisture content resulting from unsaturated drainage during winter when frozen ground prevented infiltration. The unsaturated hydraulic conductivity calculated from these data ranged from approximately 10(-6)cm/s for the slow winter drainage in the absence of significant recharge to 10(-2)cm/s or higher for shallow waste subject to high infiltration through apparent preferential pathways. These two very different approaches to field-scale measurements of vertical hydraulic conductivity provide insight into the nature of fluid movement in saturated and unsaturated waste masses. It is suggested that the principles of unsaturated seepage apply reasonably well for landfilled waste and that the hydraulic behavior of waste is profoundly influenced by the nature and size of voids and by the degree of saturation prevailing in the

  1. Soil water availability as controlling factor for actual evapotranspiration in urban soil-vegetation-systems

    NASA Astrophysics Data System (ADS)

    Thomsen, Simon; Reisdorff, Christoph; Gröngröft, Alexander; Jensen, Kai; Eschenbach, Annette

    2015-04-01

    The City of Hamburg is characterized by a large number of greens, parks and roadside trees: 600.000 trees cover about 14% of the city area, and moreover, 245.000 roadside trees can be found here. Urban vegetation is generally known to positively contribute to the urban micro-climate via cooling by evapotranspiration (ET). The water for ET is predominantly stored in the urban soils. Hence, the actual evapotranspiration (ETa) is - beside atmospheric drivers - determined by soil water availability at the soil surface and in the rooting zones of the respective vegetation. The overall aim of this study is to characterize soil water availability as a regulative factor for ETa in urban soil-vegetation systems. The specific questions addressed are: i) What is the spatio-temporal variation in soil water availability at the study sites? ii) Which soil depths are predominantly used for water uptake by the vegetation forms investigated? and iii) Which are the threshold values of soil water tension and soil water content (Θ), respectively, that limit ETa under dry conditions on both grass-dominated and tree-dominated sites? Three study areas were established in the urban region of Hamburg, Germany. We selected areas featuring both single tree stands and grass-dominated sites, both representing typical vegetation forms in Hamburg. The areas are characterized by relatively dry soil conditions. However, they differ in regard to soil water availability. At each area we selected one site dominated by Common Oak (Quercus ruber L.) with ages from 40 to 120 years, and paired each oak tree site with a neighboring grass-dominated site. All field measurements were performed during the years 2013 and 2014. At each site, we continuously measured soil water tension and Θ up to 160 cm depth, and xylem sap flux of each of three oak trees per site in a 15 min-resolution. Furthermore, we measured soil hydraulic properties as pF-curve, saturated and unsaturated conductivity at all sites

  2. Using Diffuse Field Theory to Interpret the H/V Spectral Ratio from Earthquake Records in a Mexico City site

    NASA Astrophysics Data System (ADS)

    Salinas, V.; Luzón, F.; Sanchez-Sesma, F. J.; Kawase, H.; Matsushima, S.; Suárez, M.; Cuéllar, A.; Rivet, D. N.; Campillo, M.

    2011-12-01

    It has been recently demonstrated that averaging the autocorrelations of ground motions within a diffuse field lead to the imaginary part of the corresponding Green's functions. This diffuse field assumption (DFA) is at the core of the proposed explanation for the microtremor H/V spectral ratio. An application was completely developed for a layered medium (Sánchez-Sesma et al., 2011). On the other hand, for sufficiently deep sources producing almost no surface waves at a 1D configuration, the 1D-DFA allows to relate the average H/V spectral ratio from earthquakes in terms of 1D Green's functions (Kawase et al., 2011). In this work we consider earthquake data recorded at the Cibeles station belonging to the Mexico City Accelerometric Network. This site is in very soft ground and more than one hundred earthquakes of various magnitudes and locations have been recorded there between 1996 and 2008. A priori we did not know if the set of records could be regarded as realizations of a diffuse field. In order to explore the characteristics of this data set, we did the averages of the autocorrelations of windows for these earthquakes. We consider various receiver-source configurations in terms of theoretical incidence angle and consider separately, when that was possible, P, S and Coda waves. We made a parametric study considering the various attributes for this data set. Although we expected significant differences for the, say, S and Coda windows, we found instead remarkable consistency of H/V for the various combinations, perhaps with some deviations for P windows. Moreover, we found that the H/V of the recorded data matches very well with the theoretical spectra computed using the imaginary part of 3D Green's function for the standard layered structure of the site. This fact strongly suggests that, thanks to multiple scattering, the seismic fields from various earthquakes can be regarded as realizations of 3D diffuse fields. Comparisons are provided for microtremor

  3. 78 FR 32462 - Wyatt Virgin Islands (V.I.), Inc., a Division of Wyatt Field Service Company, Working On-Site at...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-30

    ... Company, Working On-Site at Hovensa, LLC Oil Refinery, Christiansted, St. Croix, U.S. Virgin Islands... Field Service Company, working on-site at HOVENSA, LLC Oil Refinery, Christiansted, St. Croix, U.S... Department's Notice of negative determination was published in the Federal Register on April 19, 2012 (77...

  4. Perceived accessibility versus actual physical accessibility of healthcare facilities.

    PubMed

    Sanchez, J; Byfield, G; Brown, T T; LaFavor, K; Murphy, D; Laud, P

    2000-01-01

    This study addressed how healthcare clinics perceive themselves in regard to accessibility for persons with spinal cord injuries (SCI). All 40 of the clinics surveyed reported that they were wheelchair accessible; however, there was significant variability in the number of sites that actually met the guidelines of the Americans with Disability Act. In general, a person using a wheelchair could enter the building, the examination room, and the bathroom. The majority of sites did not have an examination table that could be lowered to wheelchair level. Most reported limited experience in working with persons with (SCI), yet they claimed to be able to assist with difficult transfers. Only one site knew about autonomic dysreflexia. Problems of accessibility appeared to be seriously compounded by the clinics' perception of how they met physical accessibility guidelines without consideration of the actual needs of persons with SCI. This study addressed the perception of accessibility as reported by clinic managers versus actual accessibility in healthcare clinics in a Midwestern metropolitan area for persons using wheelchairs. PMID:10754921

  5. LiDAR, geophysical and field surveys at Ancient Epomanduodurum site and its surrounding country (Doubs, Eastern France)

    NASA Astrophysics Data System (ADS)

    Laplaige, Clement; Bossuet, Gilles; Thivet, Matthieu

    2010-05-01

    Integrated geophysical studies were carried out over several years, at Mandeure-Mathay (Franche-Comté Region, Eastern France) for the archaeological evaluation of ancient Epomanduodurum. The site is of major scientific interest to understand the territorial structure of earlier agglomerations in Eastern Gaul at the end of the Iron Age and during the Roman period. As regards its size, urban equipment, monuments and function, the ancient town is considered rating second behind the civitas capital of Sequani, Besançon-Vesontio. It is located in the Doubs valley, where the plain of Alsace opens into the marches of Burgundy, in a traffic zone between the Vosges and the Jura. This location allows transit between the Rhône valley and the Rhein plain, through the Saône and Doubs valleys. This geographical situation was a significant factor in the creation of the late Iron Age settlement, later to turn into a major Gallo-roman town. The whole site of the Ancient town includes urban centre and two artisan suburbs. The buried ruins stretch on more than 500 hectares outside and inside a meander of the Doubs River. From the beginning of the survey, in 2001, high resolution and non invasive geophysical methods (magnetic mapping and Automatic Restivity Profiling (ARP) were performed on large scale, both on the terrace and in the floodplain). Excavations associated to geophysical prospection allow to produce a general plan of the Gallo roman structures and to reconstruct the settlement evolution. While human occupation on open land is certified by a lot of indications, on the contrary, the forest-covered zones on table-land appear as less documented areas. The explanation is that some of the classic methods (such as aerial reconnaissance and field walking) are less efficient in the archaeological prospection of table-lands and hills, naturally marked by omnipresent forest. In our new research program (LIEPPEC and PCR Mandeure, 2008-2010), it appears necessary to better

  6. Site Environmental Report for Calendar Year 2005. DOE Operations at The Boeing Company, Santa Susana Field Laboratory, Area IV

    SciTech Connect

    2006-09-30

    This annual report describes the environmental monitoring programs related to the Department of Energy’s (DOE) activities at the Santa Susana Field Laboratory (SSFL) facility located in Ventura County, California during 2005. Part of the SSFL facility, known as Area IV, had been used for DOE’s activities since the 1950s. A broad range of energy related research and development (R&D) projects, including nuclear technologies projects, was conducted at the site. All the nuclear R&D operations in Area IV ceased in 1988. Current efforts are directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and closure of facilities used for liquid metal research.

  7. Site-specific distribution and competitive ability of indigenous bean-nodulating rhizobia isolated from organic fields in Minnesota.

    PubMed

    Wongphatcharachai, Manoosak; Wang, Ping; Staley, Christopher; Chun, Chan Lan; Ferguson, John A; Moncada, Kristine M; Sheaffer, Craig C; Sadowsky, Michael J

    2015-11-20

    Organic dry bean production systems have received increasing interest in many regions of the US, including Minnesota. Thus, improving biological N2 fixation would be highly beneficial for organic crop production. To date, only limited work has been done to select efficient N2-fixing rhizobia for organic dry bean production. In this study, soil samples from 25 organic fields in Minnesota, with a previous cropping history of dry beans, soybeans or both, were collected during May to July 2012. Genetic diversity of indigenous dry bean-rhizobia (511 isolates) was determined by using horizontal, fluorophore-enhanced, repetitive, extragenic, and palindromic-PCR (HFERP) DNA fingerprinting and isolates were classified as belonging to 58 different genotypes. The more abundant rhizobia isolated from bean nodules comprised 35.6% of the population. None of the isolates were identical to commonly-used commercial strains used in the U.S., including Rhizobium tropici CIAT899. Seventeen predominant genotypes were shown to represent two main species, Rhizobium leguminosarum bv. phaseoli (67.1%) and Rhizobium etli (30.2%). One of the indigenous strains, orgK9, displayed efficient N2-fixation and competitive ability relative to the commercial strains tested. The lack of large numbers of indigenous dry bean-rhizobia at most study sites will be useful to avoid competition problems between inoculant strains and indigenous rhizobia. This will allow inoculation with highly effective N2-fixing rhizobia, thus resulting in improved crop productivity. Our results highlight the existence of site-specific rhizobial genotypes in different organic fields and identify strains that may prove useful as novel inoculants for organic dry bean production systems.

  8. Field metabolomics and laboratory assessments of anaerobic intrinsic bioremediation of hydrocarbons at a petroleum‐contaminated site

    PubMed Central

    Parisi, Victoria A.; Brubaker, Gaylen R.; Zenker, Matthew J.; Prince, Roger C.; Gieg, Lisa M.; Da Silva, Marcio L.B.; Alvarez, Pedro J. J.; Suflita, Joseph M.

    2009-01-01

    Summary Field metabolomics and laboratory assays were used to assess the in situ anaerobic attenuation of hydrocarbons in a contaminated aquifer underlying a former refinery. Benzene, ethylbenzene, 2‐methylnaphthalene, 1,2,4‐ and 1,3,5‐trimethylbenzene were targeted as contaminants of greatest regulatory concern (COC) whose intrinsic remediation has been previously reported. Metabolite profiles associated with anaerobic hydrocarbon decay revealed the microbial utilization of alkylbenzenes, including the trimethylbenzene COC, PAHs and several n‐alkanes in the contaminated portions of the aquifer. Anaerobic biodegradation experiments designed to mimic in situ conditions showed no loss of exogenously amended COC; however, a substantive rate of endogenous electron acceptor reduction was measured (55 ± 8 µM SO4 day−1). An assessment of hydrocarbon loss in laboratory experiments relative to a conserved internal marker revealed that non‐COC hydrocarbons were being metabolized. Purge and trap analysis of laboratory assays showed a substantial loss of toluene, m‐ and o‐xylene, as well as several alkanes (C6–C12). Multiple lines of evidence suggest that benzene is persistent under the prevailing site anaerobic conditions. We could find no in situ benzene intermediates (phenol or benzoate), the parent molecule proved recalcitrant in laboratory assays and low copy numbers of Desulfobacterium were found, a genus previously implicated in anaerobic benzene biodegradation. This study also showed that there was a reasonable correlation between field and laboratory findings, although with notable exception. Thus, while the intrinsic anaerobic bioremediation was clearly evident at the site, non‐COC hydrocarbons were preferentially metabolized, even though there was ample literature precedence for the biodegradation of the target molecules. PMID:21261914

  9. Field metabolomics and laboratory assessments of anaerobic intrinsic bioremediation of hydrocarbons at a petroleum-contaminated site.

    PubMed

    Parisi, Victoria A; Brubaker, Gaylen R; Zenker, Matthew J; Prince, Roger C; Gieg, Lisa M; Da Silva, Marcio L B; Alvarez, Pedro J J; Suflita, Joseph M

    2009-03-01

    Field metabolomics and laboratory assays were used to assess the in situ anaerobic attenuation of hydrocarbons in a contaminated aquifer underlying a former refinery. Benzene, ethylbenzene, 2-methylnaphthalene, 1,2,4- and 1,3,5-trimethylbenzene were targeted as contaminants of greatest regulatory concern (COC) whose intrinsic remediation has been previously reported. Metabolite profiles associated with anaerobic hydrocarbon decay revealed the microbial utilization of alkylbenzenes, including the trimethylbenzene COC, PAHs and several n-alkanes in the contaminated portions of the aquifer. Anaerobic biodegradation experiments designed to mimic in situ conditions showed no loss of exogenously amended COC; however, a substantive rate of endogenous electron acceptor reduction was measured (55 ± 8 µM SO(4) day(-1)). An assessment of hydrocarbon loss in laboratory experiments relative to a conserved internal marker revealed that non-COC hydrocarbons were being metabolized. Purge and trap analysis of laboratory assays showed a substantial loss of toluene, m- and o-xylene, as well as several alkanes (C(6)-C(12)). Multiple lines of evidence suggest that benzene is persistent under the prevailing site anaerobic conditions. We could find no in situ benzene intermediates (phenol or benzoate), the parent molecule proved recalcitrant in laboratory assays and low copy numbers of Desulfobacterium were found, a genus previously implicated in anaerobic benzene biodegradation. This study also showed that there was a reasonable correlation between field and laboratory findings, although with notable exception. Thus, while the intrinsic anaerobic bioremediation was clearly evident at the site, non-COC hydrocarbons were preferentially metabolized, even though there was ample literature precedence for the biodegradation of the target molecules.

  10. Efficient implementation of three-dimensional reference interaction site model self-consistent-field method: application to solvatochromic shift calculations.

    PubMed

    Minezawa, Noriyuki; Kato, Shigeki

    2007-02-01

    The authors present an implementation of the three-dimensional reference interaction site model self-consistent-field (3D-RISM-SCF) method. First, they introduce a robust and efficient algorithm for solving the 3D-RISM equation. The algorithm is a hybrid of the Newton-Raphson and Picard methods. The Jacobian matrix is analytically expressed in a computationally useful form. Second, they discuss the solute-solvent electrostatic interaction. For the solute to solvent route, the electrostatic potential (ESP) map on a 3D grid is constructed directly from the electron density. The charge fitting procedure is not required to determine the ESP. For the solvent to solute route, the ESP acting on the solute molecule is derived from the solvent charge distribution obtained by solving the 3D-RISM equation. Matrix elements of the solute-solvent interaction are evaluated by the direct numerical integration. A remarkable reduction in the computational time is observed in both routes. Finally, the authors implement the first derivatives of the free energy with respect to the solute nuclear coordinates. They apply the present method to "solute" water and formaldehyde in aqueous solvent using the simple point charge model, and the results are compared with those from other methods: the six-dimensional molecular Ornstein-Zernike SCF, the one-dimensional site-site RISM-SCF, and the polarizable continuum model. The authors also calculate the solvatochromic shifts of acetone, benzonitrile, and nitrobenzene using the present method and compare them with the experimental and other theoretical results. PMID:17302489

  11. Field monitoring and performance evaluation of an in situ air sparging system at a gasoline-contaminated site.

    PubMed

    Hall, B L; Lachmar, T E; Dupont, R R

    2000-06-30

    In situ air sparging (IAS) has been used since the mid-1980s, but few carefully designed field studies have been performed to evaluate its effectiveness. In this study, 27 discrete monitoring points (MPs) were installed at a gasoline-contaminated site to investigate the efficacy of IAS. Each MP was instrumented with a pressure transducer and a Technalithics dissolved oxygen (DO) probe, and located so they could be used to characterize subsurface changes in total head and DO with depth, distance and orientation around a central injection well. Because the blower over-heated and automatically shut down after approximately 30 min and short-circuiting of air into two MPs occurred within 2 min, the study was designed as three sets of three 30-min trials. Longer trials would not have yielded different nor more insightful results. A volume of soil was not oxygenated during any injection. Instead, air traveled directly to at least four of seven different MPs during eight of the nine trials, probably as a result of an air bubble forming beneath a confining layer. The order of air arrival at the MPs varied during the first few trials, but once a preferential pathway was established, it did not collapse between trials and provided the shortest distance to the vadose zone during subsequent trials. Oxygen uptake rates estimated for MPs that received air during any trial exceeded the consumption rates of the Technalithics DO probes, and indicate that the probes could be used for estimating oxygen transfer during system operation or for oxygen uptake measurements during shut-down tests. The data from the monitoring system indicate that IAS is infeasible for remediation of soil and groundwater at this site due to its low horizontal hydraulic conductivity. Similar behavior is anticipated when IAS is applied at other sites with low hydraulic conductivity materials. PMID:10794912

  12. Field monitoring and performance evaluation of an in situ air sparging system at a gasoline-contaminated site.

    PubMed

    Hall, B L; Lachmar, T E; Dupont, R R

    2000-06-30

    In situ air sparging (IAS) has been used since the mid-1980s, but few carefully designed field studies have been performed to evaluate its effectiveness. In this study, 27 discrete monitoring points (MPs) were installed at a gasoline-contaminated site to investigate the efficacy of IAS. Each MP was instrumented with a pressure transducer and a Technalithics dissolved oxygen (DO) probe, and located so they could be used to characterize subsurface changes in total head and DO with depth, distance and orientation around a central injection well. Because the blower over-heated and automatically shut down after approximately 30 min and short-circuiting of air into two MPs occurred within 2 min, the study was designed as three sets of three 30-min trials. Longer trials would not have yielded different nor more insightful results. A volume of soil was not oxygenated during any injection. Instead, air traveled directly to at least four of seven different MPs during eight of the nine trials, probably as a result of an air bubble forming beneath a confining layer. The order of air arrival at the MPs varied during the first few trials, but once a preferential pathway was established, it did not collapse between trials and provided the shortest distance to the vadose zone during subsequent trials. Oxygen uptake rates estimated for MPs that received air during any trial exceeded the consumption rates of the Technalithics DO probes, and indicate that the probes could be used for estimating oxygen transfer during system operation or for oxygen uptake measurements during shut-down tests. The data from the monitoring system indicate that IAS is infeasible for remediation of soil and groundwater at this site due to its low horizontal hydraulic conductivity. Similar behavior is anticipated when IAS is applied at other sites with low hydraulic conductivity materials.

  13. Site Environmental Report for Calendar Year 2004. DOE Operations at The Boeing Company Santa Susana Field Laboratory

    SciTech Connect

    Liu, Ning; Rutherford, Phil; Lee, Majelle

    2005-09-01

    This Annual Site Environmental Report (ASER) for 2004 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). In the past, the Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder components. All nuclear work was terminated in 1988; all subsequent radiological work has been directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Closure of the liquid metal test facilities began in 1996. Results of the radiological monitoring program for the calendar year 2004 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.

  14. Site Environmental Report for Calendar Year 2010. DOE Operations at The Boeing Company Santa Susana Field Laboratory, Area IV

    SciTech Connect

    Liu, Ning; Rutherford, Phil; Amar, Ravnesh

    2011-09-01

    This Annual Site Environmental Report (ASER) for 2010 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2010 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.

  15. Site Environmental Report for Calendar Year 2011. DOE Operations at The Boeing Company Santa Susana Field Laboratory, Area IV

    SciTech Connect

    Liu, Ning; Rutherford, Phil; Dassler, David

    2012-09-01

    This Annual Site Environmental Report (ASER) for 2011 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, operation and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward environmental restoration and decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2011 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.

  16. Site Environmental Report For Calendar Year 2012. DOE Operations at The Boeing Company Santa Susana Field Laboratory, Area IV

    SciTech Connect

    Liu, Ning; Rutherford, Phil; Dassler, David

    2013-09-01

    This Annual Site Environmental Report (ASER) for 2012 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, operation and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward environmental restoration and decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2012 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.

  17. Site Environmental Report for Calendar Year 2008. DOE Operations at The Boeing Company Santa Susana Field Laboratory, Area IV

    SciTech Connect

    Liu, Ning; Rutherford, Phil; Amar, Ravnesh

    2009-09-01

    This Annual Site Environmental Report (ASER) for 2008 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988; all subsequent radiological work has been directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. In May 2007, the D&D operations in Area IV were suspended by the DOE. The environmental monitoring programs were continued throughout the year. Results of the radiological monitoring program for the calendar year 2008 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.

  18. Site Environmental Report for Calendar Year 2009. DOE Operations at The Boeing Company Santa Susana Field Laboratory, Area IV

    SciTech Connect

    Liu, Ning; Rutherford, Phil; Amar, Ravnesh

    2010-09-01

    This Annual Site Environmental Report (ASER) for 2009 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). The Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder reactor components. All nuclear work was terminated in 1988, and all subsequent radiological work has been directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Liquid metal research and development ended in 2002. Since May 2007, the D&D operations in Area IV have been suspended by the DOE, but the environmental monitoring and characterization programs have continued. Results of the radiological monitoring program for the calendar year 2009 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.

  19. Site Environmental Report for Calendar Year 2006. DOE Operations at The Boeing Company Santa Susana Field Laboratory, Area IV

    SciTech Connect

    Liu, Ning; Rutherford, Phil

    2007-09-01

    This Annual Site Environmental Report (ASER) for 2006 describes the environmental conditions related to work performed for the Department of Energy (DOE) at Area IV of Boeing’s Santa Susana Field Laboratory (SSFL). In the past, the Energy Technology Engineering Center (ETEC), a government-owned, company-operated test facility, was located in Area IV. The operations in Area IV included development, fabrication, and disassembly of nuclear reactors, reactor fuel, and other radioactive materials. Other activities in the area involved the operation of large-scale liquid metal facilities that were used for testing non-nuclear liquid metal fast breeder components. All nuclear work was terminated in 1988; all subsequent radiological work has been directed toward decontamination and decommissioning (D&D) of the former nuclear facilities and their associated sites. Closure of the liquid metal test facilities began in 1996. Results of the radiological monitoring program for the calendar year 2006 continue to indicate that there are no significant releases of radioactive material from Area IV of SSFL. All potential exposure pathways are sampled and/or monitored, including air, soil, surface water, groundwater, direct radiation, transfer of property (land, structures, waste), and recycling.

  20. Field Investigation to Determine the Extent of Sediment Recontamination at the United Heckathorn Superfund Site, Richmond, California

    SciTech Connect

    Kohn, Nancy P.; Gilmore, Tyler J.

    2001-11-16

    This field investigation was undertaken to determine the present condition of sediment in Lauritzen Channel and Parr Canal approximately 2 years after completion of sediment remedial actions at the United Heckathorn Superfund site. The study was designed to supplement the post-remediation monitoring program by determining the extent and identifying potential sources of observed pesticide contamination in marine sediments near the site. Core samples collected from Lauritzen Channel and Parr Canal in July 1999 were described geologically, and samples were prepared from different sediment types, such as younger bay mud or older bay mud. Sediment samples were analyzed for grain size, organic carbon, and DDT compounds. Only minor changes have occurred in Parr Canal since remedial actions were taken in 1996-1997, but in Lauritzen Channel, DDT concentrations exceed the remedial goal of 590 ug/kg dry weight in nearly all the unconsolidated sediment (younger bay mud, sand, and disturbed older bay mud). The source of contaminated sediment could not be confirmed by this study; there was no clear correlation between high DDT concentrations and sediment remaining between the pilings, as was originally suspected. There also was no correlation between high DDT concentrations in sediment and the locations of outfalls, although some of the contamination retained by the creosote-treated wood appeared to be highest close to the known outfalls.

  1. Field evaluation of a horizontal well recirculation system for groundwater treatment: Pilot test at the Clean Test Site Portsmouth Gaseous Diffusion Plant, Piketon, Ohio

    SciTech Connect

    Muck, M.T.; Kearl, P.M.; Siegrist, R.L.

    1998-08-01

    This report presents the results of field testing a horizontal well recirculation system at the Portsmouth Gaseous Diffusion Plant (PORTS). The recirculation system uses a pair of horizontal wells, one for groundwater extraction and treatment and the other for reinjection of treated groundwater, to set up a recirculation flow field. The induced flow field from the injection well to the extraction well establishes a sweeping action for the removal and treatment of groundwater contaminants. The overall purpose of this project is to study treatment of mixed groundwater contaminants that occur in a thin water-bearing zone not easily targeted by traditional vertical wells. The project involves several research elements, including treatment-process evaluation, hydrodynamic flow and transport modeling, pilot testing at an uncontaminated site, and pilot testing at a contaminated site. The results of the pilot test at an uncontaminated site, the Clean Test Site (CTS), are presented in this report.

  2. Spatio-temporal patterns and covariance structures of soil water status in two Northeast-German field sites

    NASA Astrophysics Data System (ADS)

    Wendroth, O.; Pohl, W.; Koszinski, S.; Rogasik, H.; Ritsema, C. J.; Nielsen, D. R.

    1999-02-01

    Spatio-temporal patterns of soil moisture status highly affect the heterogeneity of soil water and solute transport and leaching of chemicals to the groundwater. In order to quantify and describe spatial variability of ecologically highly relevant spatial and temporal processes linked to soil moisture at the land surface, the spatio-temporal covariance structure and the reasons for its change in time need to be identified. Therefore, soil water pressure head was monitored in two surface horizons between April and November 1995 at two field sites with a shallow ground water table, a sandy loam and a heavy clay soil in north-east Germany. For the 10- and the 30-cm depth of the sandy loam soil and for the 30-cm depth of the heavy clay soil the variance of soil water pressure head h (on log basis) was large under wet conditions. With decreasing soil water pressure head the variance of log 10(- h) decreased to a critical value, for which a spatial correlation structure disappeared. With further drying, the variance of log 10(- h) increased again, and a spatial range of correlation existed. During drying, temporally stable variation patterns developed at both field sites. The change of variance of log 10(- h) which is probably associated with changing degree of heterogeneity of flow conditions validates the findings of Roth (1995) obtained from stochastic flow model calculations. In general, the temporal correlation length was better defined than that of spatial correlation. At both depths, correlation lengths of the sandy loam were larger than those of the heavy clay soil. Random spatial variation of log 10(- h) occurred under conditions when the hydraulic gradient was close to zero. With our experimental design we could identify (i) temporal persistence of spatial patterns and correlation ranges of soil water status that can be used for representativity studies, (ii) the within-site variation of land surface moisture status, and (iii) a basis for description of spatial

  3. Data collection and field experiments at the Apache Leap research site. Annual report, May 1995--1996

    SciTech Connect

    Woodhouse, E.G.; Bassett, R.L.; Neuman, S.P.; Chen, G.

    1997-08-01

    This report documents the research performed during the period May 1995-May 1996 for a project of the U.S. Regulatory Commission (sponsored contract NRC-04-090-051) by the University of Arizona. The project manager for this research in Thomas J. Nicholson, Office of Nuclear Regulatory Research. The objectives of this research were to examine hypotheses and test alternative conceptual models concerning unsaturated flow and transport through fractured rock, and to design and execute confirmatory field and laboratory experiments to test these hypotheses and conceptual models at the Apache Leap Research Site near Superior, Arizona. Each chapter in this report summarizes research related to a specific set of objectives and can be read and interpreted as a separate entity. Topics include: crosshole pneumatic and gaseous tracer field and modeling experiments designed to help validate the applicability of contiuum geostatistical and stochastic concepts, theories, models, and scaling relations relevant to unsaturated flow and transport in fractured porous tuffs; use of geochemistry and aquifer testing to evaluate fracture flow and perching mechanisms; investigations of {sup 234}U/{sup 238}U fractionation to evaluate leaching selectivity; and transport and modeling of both conservative and non-conservative tracers.

  4. Costs for off-site disposal of nonhazardous oil field wastes: Salt caverns versus other disposal methods

    SciTech Connect

    Veil, J.A.

    1997-09-01

    According to an American Petroleum Institute production waste survey reported on by P.G. Wakim in 1987 and 1988, the exploration and production segment of the US oil and gas industry generated more than 360 million barrels (bbl) of drilling wastes, more than 20 billion bbl of produced water, and nearly 12 million bbl of associated wastes in 1985. Current exploration and production activities are believed to be generating comparable quantities of these oil field wastes. Wakim estimates that 28% of drilling wastes, less than 2% of produced water, and 52% of associated wastes are disposed of in off-site commercial facilities. In recent years, interest in disposing of oil field wastes in solution-mined salt caverns has been growing. This report provides information on the availability of commercial disposal companies in oil-and gas-producing states, the treatment and disposal methods they employ, and the amounts they charge. It also compares cavern disposal costs with the costs of other forms of waste disposal.

  5. Self-Actualization, Liberalism, and Humanistic Education.

    ERIC Educational Resources Information Center

    Porter, Charles Mack

    1979-01-01

    The relationship between personality factors and political orientation has long been of interest to psychologists. This study tests the hypothesis that there is no significant relationship between self-actualization and liberalism-conservatism. The hypothesis is supported. (Author)

  6. Efficacy of burning, tillage, and biocides in controlling bacteria released at field sites and effects on indigenous bacteria and fungi.

    PubMed

    Donegan, K; Fieland, V; Fowles, N; Ganio, L; Seidler, R

    1992-04-01

    Decontamination treatments of burning and biocide application, alone and in combination with tillage, were evaluated for their ability to reduce populations of bacteria applied to the leaves of plants in field plots. In addition, the effects of these control methods on indigenous leaf and soil bacteria and fungi were assessed. Field plots of bush beans (Phaseolus vulgaris), sprayed with the bacterium Pseudomonas syringae, Pseudomonas fluorescens, or Erwinia herbicola, received the following treatments: (i) control, (ii) tillage, (iii) burning, (iv) burning plus tillage (burn-tillage), (v) Kocide (cupric hydroxide), (vi) Kocide plus tillage, (vii) Agri-Strep (streptomycin sulfate), and (viii) Agri-Strep plus tillage. Leaves and soil from the plots were sampled at 1 day before and at 1, 3, 7, 10, 14, 21, and 30 days after application of the decontamination treatments. The burn and burn-tillage treatments produced the most significant reductions in bacterial populations. The Agri-Strep treatment was more effective than the Kocide treatment in eliminating applied bacteria, but neither biocide produced consistent or persistent control. In contrast, the tillage treatment, alone or in combination with the Agri-Strep or Kocide treatments, had a short-term stimulatory effect and increased populations of applied bacteria and also levels of indigenous fungi and bacteria. Agri-Strep and Kocide treatments caused significant reductions in indigenous bacterial populations up to 14 days after application and in indigenous fungal populations on day 7 after application. Our results suggest that conventional plant disease control methods may not provide satisfactory control of genetically engineered microorganisms and indicate a need for further development of effective and selective methods to control release microorganisms at field sites. PMID:1599240

  7. Efficacy of burning, tillage, and biocides in controlling bacteria released at field sites and effects on indigenous bacteria and fungi.

    PubMed Central

    Donegan, K; Fieland, V; Fowles, N; Ganio, L; Seidler, R

    1992-01-01

    Decontamination treatments of burning and biocide application, alone and in combination with tillage, were evaluated for their ability to reduce populations of bacteria applied to the leaves of plants in field plots. In addition, the effects of these control methods on indigenous leaf and soil bacteria and fungi were assessed. Field plots of bush beans (Phaseolus vulgaris), sprayed with the bacterium Pseudomonas syringae, Pseudomonas fluorescens, or Erwinia herbicola, received the following treatments: (i) control, (ii) tillage, (iii) burning, (iv) burning plus tillage (burn-tillage), (v) Kocide (cupric hydroxide), (vi) Kocide plus tillage, (vii) Agri-Strep (streptomycin sulfate), and (viii) Agri-Strep plus tillage. Leaves and soil from the plots were sampled at 1 day before and at 1, 3, 7, 10, 14, 21, and 30 days after application of the decontamination treatments. The burn and burn-tillage treatments produced the most significant reductions in bacterial populations. The Agri-Strep treatment was more effective than the Kocide treatment in eliminating applied bacteria, but neither biocide produced consistent or persistent control. In contrast, the tillage treatment, alone or in combination with the Agri-Strep or Kocide treatments, had a short-term stimulatory effect and increased populations of applied bacteria and also levels of indigenous fungi and bacteria. Agri-Strep and Kocide treatments caused significant reductions in indigenous bacterial populations up to 14 days after application and in indigenous fungal populations on day 7 after application. Our results suggest that conventional plant disease control methods may not provide satisfactory control of genetically engineered microorganisms and indicate a need for further development of effective and selective methods to control release microorganisms at field sites. PMID:1599240

  8. Food chain transfer and potential renal toxicity of mercury to small mammals at a contaminated terrestrial field site.

    PubMed

    Talmage, S S; Walton, B T

    1993-12-01

    Mercury concentrations were determined in surface soil and biota at a contaminated terrestrial field site and were used to calculate transfer coefficients of mercury through various compartments of the ecosystem based on trophic relationships. Mercury concentrations in all compartments (soil, vegetation, invertebrates, and small mammals) were higher than mercury concentrations in corresponding samples at local reference sites. Nonetheless, mercury concentrations in biota did not exceed concentrations in the contaminated surface soil, which averaged 269 μg g(-1). Plant tissue concentrations of mercury were low (0.01 to 2.0 μg g(-1)) and yielded soil to plant transfer coefficients ranging from 3.7×10(-5) for seeds to 7.0×10(-3) for grass blades. Mercury concentrations in invertebrates ranged from 0.79 for harvestmen (Phalangida) to 15.5 μg g(-1) for undepurated earthworms (Oligochaeta). Mean food chain transfer coefficients for invertebrates were 0.88 for herbivores/omnivores and 2.35 for carnivores. Mean mercury concentrations in target tissue (kidney) were 1.16±1.16 μg g(-1) for the white-footed mouse (Peromyscus leucopus), a granivore, and 38.8±24.6 μg g(-1) for the shorttail shrew (Blarina brevicauda), an insectivore. Transfer coefficients for diet to kidney were 0.75 and 4.40 for P. leucopus and B. brevicauda, respectively. A comparison of kidney mercury residues measured in this study with values from controlled laboratory feeding studies from the literature indicate that B. brevicauda but not P. leucopus may be ingesting mercury at levels that are nephrotoxic. PMID:24201735

  9. The saxitoxin/tetrodotoxin binding site on cloned rat brain IIa Na channels is in the transmembrane electric field.

    PubMed Central

    Satin, J.; Limberis, J. T.; Kyle, J. W.; Rogart, R. B.; Fozzard, H. A.

    1994-01-01

    The rat brain IIa (BrIIa) Na channel alpha-subunit and the brain beta 1 subunit were coexpressed in Xenopus oocytes, and peak whole-oocyte Na current (INa) was measured at a test potential of -10 mV. Hyperpolarization of the holding potential resulted in an increased affinity of STX and TTX rested-state block of BrIIa Na channels. The apparent half-block concentration (ED50) for STX of BrIIa current decreased with hyperpolarizing holding potentials (Vhold). At Vhold of -100 mV, the ED50 was 2.1 +/- 0.4 nM, and the affinity increased to a ED50 of 1.2 +/- 0.2 nM with Vhold of -140 mV. In the absence of toxin, the peak current amplitude was the same for all potentials negative to -90 mV, demonstrating that all of the channels were in a closed conformation and maximally available to open in this range of holding potentials. The Woodhull model (1973) was used to describe the increase of the STX ED50 as a function of holding potential. The equivalent electrical distance of block (delta) by STX was 0.18 from the extracellular milieu when the valence of STX was fixed to +2. Analysis of the holding potential dependence of TTX block yielded a similar delta when the valence of TTX was fixed to +1. We conclude that the guanidinium toxin site is located partially within the transmembrane electric field. Previous site-directed mutagenesis studies demonstrated that an isoform-specific phenylalanine in the BrIIa channel is critical for high affinity toxin block. Therefore, we propose that amino acids at positions corresponding to this Phe in the BrIIa channel, which lie in the outer vestibule of the channel adjacent to the pore entrance,are partially in the transmembrane potential drop. PMID:7811911

  10. Food chain transfer and potential renal toxicity of mercury to small mammals at a contaminated terrestrial field site.

    PubMed

    Talmage, S S; Walton, B T

    1993-12-01

    Mercury concentrations were determined in surface soil and biota at a contaminated terrestrial field site and were used to calculate transfer coefficients of mercury through various compartments of the ecosystem based on trophic relationships. Mercury concentrations in all compartments (soil, vegetation, invertebrates, and small mammals) were higher than mercury concentrations in corresponding samples at local reference sites. Nonetheless, mercury concentrations in biota did not exceed concentrations in the contaminated surface soil, which averaged 269 μg g(-1). Plant tissue concentrations of mercury were low (0.01 to 2.0 μg g(-1)) and yielded soil to plant transfer coefficients ranging from 3.7×10(-5) for seeds to 7.0×10(-3) for grass blades. Mercury concentrations in invertebrates ranged from 0.79 for harvestmen (Phalangida) to 15.5 μg g(-1) for undepurated earthworms (Oligochaeta). Mean food chain transfer coefficients for invertebrates were 0.88 for herbivores/omnivores and 2.35 for carnivores. Mean mercury concentrations in target tissue (kidney) were 1.16±1.16 μg g(-1) for the white-footed mouse (Peromyscus leucopus), a granivore, and 38.8±24.6 μg g(-1) for the shorttail shrew (Blarina brevicauda), an insectivore. Transfer coefficients for diet to kidney were 0.75 and 4.40 for P. leucopus and B. brevicauda, respectively. A comparison of kidney mercury residues measured in this study with values from controlled laboratory feeding studies from the literature indicate that B. brevicauda but not P. leucopus may be ingesting mercury at levels that are nephrotoxic.

  11. Field investigations and on-site toxicity testing: an assessment of habitat suitability-Arkansas River, Pueblo, Colorado

    SciTech Connect

    Keefe, D.F.; Baldridge, D.A.; Iley, G.; Nimmo, D.R.

    1981-10-01

    An on-site bioassay and aquatic ecological survey were conducted on the Arkansas River near Pueblo, CO. A mobile bioassay trailer was used to test the toxicity of sewage treatment plant (STP) effluent using Arkansas River water for dilution. The aquatic survey was conducted upstream and downstream of the STP's outfall. This study was conceived in accordance with the intent of the U.S. Environmental Protection Agency's (EPA) site-specific water quality criteria guidelines, which recognize that national criteria may not be applicable to species in specific bodies of water because of biological, chemical, and physical variables. Flow-through tests were conducted using bluegill sunfish (Lepomis macrochirus), fathead minnow (Pimephales promelas), and a daphnid (Daphnia magna). Standard field and laboratory techniques were used to evaluate physical and biological components of the stream ecosystem. The physical components included flow, substrate, and qualitative fishery habitat description, and the biological components included benthic macroinvertebrate densities, diversity calculations, and fish population surveys. The results of the bioassay tests generally indicated the following: there were distinct differences in species' sensitivity to the effluent (that is, the sensitivity was bluegills > fathead minnows > daphnid); the required dissolved oxygen (DO) concentrations in the test tanks were difficult to maintain even though the flow-through rate was increased to four times that required by protocol; the toxicity of the postchlorinated/dechlorinated effluent was less than that of the prechlorinated effluent; no single pollutant could be targeted as the toxic fraction, however, concentrations of chlorine, cyanide, copper, and zinc were at or near LC/sub 50/ values for the test organisms.

  12. The actual citation impact of European oncological research.

    PubMed

    López-Illescas, Carmen; de Moya-Anegón, Félix; Moed, Henk F

    2008-01-01

    This study provides an overview of the research performance of major European countries in the field Oncology, the most important journals in which they published their research articles, and the most important academic institutions publishing them. The analysis was based on Thomson Scientific's Web of Science (WoS) and calculated bibliometric indicators of publication activity and actual citation impact. Studying the time period 2000-2006, it gives an update of earlier studies, but at the same time it expands their methodologies, using a broader definition of the field, calculating indicators of actual citation impact, and analysing new and policy relevant aspects. Findings suggest that the emergence of Asian countries in the field Oncology has displaced European articles more strongly than articles from the USA; that oncologists who have published their articles in important, more general journals or in journals covering other specialties, rather than in their own specialist journals, have generated a relatively high actual citation impact; and that universities from Germany, and--to a lesser extent--those from Italy, the Netherlands, UK, and Sweden, dominate a ranking of European universities based on number of articles in oncology. The outcomes illustrate that different bibliometric methodologies may lead to different outcomes, and that outcomes should be interpreted with care.

  13. Uncertainties in Eddy Covariance fluxes due to post-field data processing: a multi-site, full factorial analysis

    NASA Astrophysics Data System (ADS)

    Sabbatini, S.; Fratini, G.; Arriga, N.; Papale, D.

    2012-04-01

    Eddy Covariance (EC) is the only technologically available direct method to measure carbon and energy fluxes between ecosystems and atmosphere. However, uncertainties related to this method have not been exhaustively assessed yet, including those deriving from post-field data processing. The latter arise because there is no exact processing sequence established for any given situation, and the sequence itself is long and complex, with many processing steps and options available. However, the consistency and inter-comparability of flux estimates may be largely affected by the adoption of different processing sequences. The goal of our work is to quantify the uncertainty introduced in each processing step by the fact that different options are available, and to study how the overall uncertainty propagates throughout the processing sequence. We propose an easy-to-use methodology to assign a confidence level to the calculated fluxes of energy and mass, based on the adopted processing sequence, and on available information such as the EC system type (e.g. open vs. closed path), the climate and the ecosystem type. The proposed methodology synthesizes the results of a massive full-factorial experiment. We use one year of raw data from 15 European flux stations and process them so as to cover all possible combinations of the available options across a selection of the most relevant processing steps. The 15 sites have been selected to be representative of different ecosystems (forests, croplands and grasslands), climates (mediterranean, nordic, arid and humid) and instrumental setup (e.g. open vs. closed path). The software used for this analysis is EddyPro™ 3.0 (www.licor.com/eddypro). The critical processing steps, selected on the basis of the different options commonly used in the FLUXNET community, are: angle of attack correction; coordinate rotation; trend removal; time lag compensation; low- and high- frequency spectral correction; correction for air density

  14. Isolation and Characterization of Mobile Genetic Elements from Microbial Assemblages Obtained from the Field Research Center Site

    SciTech Connect

    Patricia Sobecky; Cassie Hodges; Kerri Lafferty; Mike Humphreys; Melanie Raimondo; Kristin Tuttle; Tamar Barkay

    2004-03-17

    Considerable knowledge has been gained from the intensive study of a relatively limited group of bacterial plasmids. Recent efforts have begun to focus on the characterization of, at the molecular level, plasmid populations and associated mobile genetic elements (e.g., transposons, integrons) occurring in a wider range of aquatic and terrestrial habitats. Surprisingly, however, little information is available regarding the incidence and distribution of mobile genetic elements extant in contaminated subsurface environments. Such studies will provide greater knowledge on the ecology of plasmids and their contributions to the genetic plasticity (and adaptation) of naturally occurring subsurface microbial communities. We requested soil cores from the DOE NABIR Field Research Center (FRC) located on the Oak Ridge Reservation. The cores, received in February 2003, were sampled from four areas on the Oak Ridge Site: Area 1, Area 2, Area 3 (representing contaminated subsurface locales) and the background reference sites. The average core length (24 in) was subdivided into three profiles and soil pH and moisture content were determined. Uranium concentration was also determined in bulk samples. Replicate aliquots were fixed for total cell counts and for bacterial isolation. Four different isolation media were used to culture aerobic and facultative microbes from these four study areas. Colony forming units ranged from a minimum of 100 per gram soil to a maximum of 10,000 irrespective of media composition used. The vast majority of cultured subsurface isolates were gram-positive isolates and plasmid characterization was conducted per methods routinely used in the Sobecky laboratory. The percentage of plasmid incidence ranged from 10% to 60% of all isolates tested. This frequency appears to be somewhat higher than the incidence of plasmids we have observed in other habitats and we are increasing the number of isolates screened to confirm this observation. We are also

  15. Responses of Mycorrhizal Symbioses to Deliberate Leaks from AN Experimental CO2 Sequestration Field: the Zert Site

    NASA Astrophysics Data System (ADS)

    Apple, M. E.; Rowe, J. O.; Zhou, X.; Jewell, S.; Dobeck, L.; Cunningham, A.; Spangler, L.

    2012-12-01

    Carbon sequestration is a means of reducing the concentration of atmospheric CO2 . It is important to monitor carbon sequestration fields for surface detection of possible leaks of CO2 . At The Zero Emissions Research Technology (ZERT) site, CO2 is injected at 0.15 tonnes/day increased to 0.3 tonnes/day into the soil through a shallow horizontal injection well with deliberate zones of leaking CO2 , which wells up through the soil and reaches concentrations of 16% w/v. The ZERT site is an experimental facility designed for developing means of surface detection of leaking CO2 and for determining the responses of plants to very high soil CO2 . Within 1 - 2 weeks of CO2 injections, dandelions and grasses begin to form circular zones of leaf dieback called hot spots. While the hotspots are visually apparent, the responses of the underground mycorrhizal symbioses to very high soil CO2 at the ZERT site are as yet undetermined. To examine the effects of leaking CO2 on mycorrhizae, we collected soil and root samples between and at the hotspots before CO2 was injected, then inoculated the rhizosphere with mycorrhizal inoculum containing spores of Glomus and Gigaspora sp., and resampled the soil and roots after three weeks of CO2 injection. We then evaluated the samples for percent mycorrhizal colonization via the line-intercept method in cleared roots in which fungal structures were stained with India-ink. Plants with mycorrhizal fungi benefit by improved P uptake, so we hypothesize that where plants have increased anthocyanin production, a symptom of P deficiency, mycorrhizal colonization would be reduced. In previous summers of the ZERT experiments, leaves have turned red/purple with CO2 exposure, and as of August, 2012, current year leaves appear to have increased anthocyanin above hotspots. Plant roots exude organic carbon into the soil, where it is used by mycorrhizal fungi. Mycorrhizal symbioses are key in the carbon dynamics of soil and in linking the above and below

  16. Modeling a tracer test at the Grimsel Test Site (GTS) using a lattice Boltzmann method and transmissivity field

    NASA Astrophysics Data System (ADS)

    Kim, J. W.; Lanyon, G. W.; Baik, M. H.; Blechschmidt, I.

    2015-12-01

    A series of tracer tests have been conducted in the Migration (MI) Shear Zone at the Grimsel Test Site (GTS) for the Colloid Formation and Migration Project (CFM). As a part of the series, a dipole test (Tracer Test Run 13-05) using radionuclides, colloids and conservative tracers was performed to determine the breakthrough between CRR99.002-i2 and BOMI87.010-i2. To date, the breakthrough data of only the conservative dye tracer (Amino-G acid) are available. In the preceding project, the Colloid and Radionuclide Retardation Project (CRR), a transmissivity field for the MI shear zone was obtained by the geostatistical inverse modeling approach. In this study, the breakthrough of the tracer was computed by a gray lattice Boltzmann method (LBM). The transmissivity field with finite elements grid was transformed to the effective fracture aperture or flow porosity according to the cubic law, and the grid was uniformalized by the interpolation. The uniform mesh of the effective aperture was utilized as the model domain of the gray LBM. In the gray LBM, the heterogeneity of the aperture was dealt with a partial-bounceback scheme. The profiles of hydraulic heads monitored at the boreholes nearby were used as the reference values in the calculation of the pressure distribution in the model domain. The modeling results could reveal a dominant pathway of tracers in the dipole test. The developed model can be utilized in the calculation of the reactive transports of radionuclides and colloids by coupling with a geochemical model, such as Phreeqc, the Geochemist's Workbench, etc.

  17. Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region and Field Trips in the Channeled Scabland, Washington

    NASA Technical Reports Server (NTRS)

    Golombek, M. P. (Editor); Edgett, K. S. (Editor); Rice, J. W., Jr. (Editor)

    1995-01-01

    This volume, the first of two comprising the technical report for this workshop, contains papers that have been accepted for presentation at the Mars Pathfinder Landing Site Workshop 2: Characteristics of the Ares Vallis Region, September 24-30, 1995, in Spokane, Washington. The Mars Pathfinder Project received a new start in October 1993 as one of the next missions in NASA's long-term Mars exploration program. The mission involves landing a single vehicle on the surface of Mars in 1997. The project is one of the first Discovery-class missions and is required to be a quick, low-cost mission and achieve a set of significant but focused engineering, science, and technology objectives. The primary objective is to demonstrate a low-cost cruise, entry, descent, and landing system required to place a payload on the martian surface in a safe, operational configuration. Additional objectives include the deployment and operation of various science instruments and a microrover. Pathfinder paves the way for a cost-effective implementation of future Mars lander missions. Also included in this volume is the field trip guide to the Channeled Scabland and Missoula Lake Break-out. On July 4, 1997, Mars Pathfinder is scheduled to land near 19.5 deg N, 32.8 deg W, in a portion of Ares Vallis. The landing ellipse covers a huge (100 x 200 km) area that appears to include both depositional and erosional landforms created by one or more giant, catastrophic floods. One of the best known terrestrial analogs to martian outflow channels (such as Ares Vallis) is the region known as the Channeled Scabland. The field trip guide describes some of the geomorphological features of the Channeled Scabland and adjacent Lake Missoula break-out area near Lake Pend Oreille, Idaho.

  18. Efficacy of drinking-water treatment residual in controlling off-site phosphorus losses: a field study in Florida.

    PubMed

    Agyin-Birikorang, S; Oladeji, O O; O'Connor, G A; Obreza, T A; Capece, J C

    2009-01-01

    Land application of drinking-water treatment residuals (WTR) has been shown to control excess soil soluble P and can reduce off-site P losses to surface and ground water. To our knowledge, no field study has directly evaluated the impacts of land application of WTRs on ground water quality. We monitored the effects of three organic sources of P (poultry manure, Boca Raton biosolids, Pompano biosolids) or triple superphosphate co-applied with an aluminum-based WTR (Al-WTR) on soil and ground water P and Al concentrations under natural field conditions for 20 mo in a soil with limited P sorption capacity. The P sources were applied at two rates (based on P or nitrogen [N] requirement of bahiagrass) with or without Al-WTR amendment and replicated three times. Without WTR application, applied P sources increased surface soil soluble P concentrations regardless of the P source or application rate. Co-applying the P sources with Al-WTR prevented increases in surface soil soluble P concentrations and reduced P losses to shallow ground water. Total dissolved P and orthophosphate concentrations of shallow well ground water of the N-based treatments were greater (>0.9 and 0.3 mg L(-1), respectively) in the absence than in the presence ( approximately 0.6 and 0.2 mg L(-1), respectively) of Al-WTR. The P-based application rate did not increase ground water P concentrations relative to background concentrations. Notwithstanding, Al-WTR amendment decreased ground water P concentrations from soil receiving treatments with P-based application rates. Ground water total dissolved Al concentrations were unaffected by soil Al-WTR application. We conclude that, at least for the study period, Al-WTR can be safely used to reduce P leaching into ground water without increasing the Al concentration of ground water. PMID:19329695

  19. Modeling Active Layer Depth Over Permafrost for the Arctic Drainage Basin and the Comparison to Measurements at CALM Field Sites

    NASA Astrophysics Data System (ADS)

    Oelke, C.; Zhang, T.; Serreze, M.; Armstrong, R.

    2002-12-01

    A finite difference model for one-dimensional heat conduction with phase change is applied to investigate soil freezing and thawing processes over the Arctic drainage basin. Calculations are performed on the 25~km~x~25~km resolution NSIDC EASE-Grid. NCEP re-analyzed sigma-0.995 surface temperature with a topography correction, and SSM/I-derived weekly snow height are used as forcing parameters. The importance of using an annual cycle of snow density for different snow classes is emphasized. Soil bulk density and the percentages of silt/clay and sand/gravel are from the SoilData System of the International Geosphere Biosphere Programme. In addition, we parameterize a spatially and vertically variable peat layer and modify soil bulk density and thermal conductivity accordingly. Climatological soil moisture content is from the Permafrost/Water Balance Model (P/WBM) at the University of New Hampshire. The model domain is divided into 3~layers with distinct thermal properties of frozen and thawed soil, respectively. Calculations are performed on 54~model nodes ranging from a thickness of 10~cm near the surface to 1~m at 15~m depth. Initial temperatures are chosen according to the grid cell's IPA permafrost classification on EASE grid. Active layer depths, simulated for the summers of 1999 and 2000, compare well to maximal thaw depths measured at about 60 Circumarctic Active Layer Monitoring Network (CALM) field sites. A remaining RMS-error between modeled and measured values is attributed mainly to scale discrepancies (100~m~x~100~m vs. 25~km~x~25~km) based on differences in the fields of air temperature, snow height, and soil bulk density. For the whole pan-Arctic land mass and the time period 1980 through 2001, this study shows the regionally highly variable active layer depth, frozen ground depth, lengths of freezing and thawing periods, and the day of year when the maxima are reached.

  20. Efficacy of drinking-water treatment residual in controlling off-site phosphorus losses: a field study in Florida.

    PubMed

    Agyin-Birikorang, S; Oladeji, O O; O'Connor, G A; Obreza, T A; Capece, J C

    2009-01-01

    Land application of drinking-water treatment residuals (WTR) has been shown to control excess soil soluble P and can reduce off-site P losses to surface and ground water. To our knowledge, no field study has directly evaluated the impacts of land application of WTRs on ground water quality. We monitored the effects of three organic sources of P (poultry manure, Boca Raton biosolids, Pompano biosolids) or triple superphosphate co-applied with an aluminum-based WTR (Al-WTR) on soil and ground water P and Al concentrations under natural field conditions for 20 mo in a soil with limited P sorption capacity. The P sources were applied at two rates (based on P or nitrogen [N] requirement of bahiagrass) with or without Al-WTR amendment and replicated three times. Without WTR application, applied P sources increased surface soil soluble P concentrations regardless of the P source or application rate. Co-applying the P sources with Al-WTR prevented increases in surface soil soluble P concentrations and reduced P losses to shallow ground water. Total dissolved P and orthophosphate concentrations of shallow well ground water of the N-based treatments were greater (>0.9 and 0.3 mg L(-1), respectively) in the absence than in the presence ( approximately 0.6 and 0.2 mg L(-1), respectively) of Al-WTR. The P-based application rate did not increase ground water P concentrations relative to background concentrations. Notwithstanding, Al-WTR amendment decreased ground water P concentrations from soil receiving treatments with P-based application rates. Ground water total dissolved Al concentrations were unaffected by soil Al-WTR application. We conclude that, at least for the study period, Al-WTR can be safely used to reduce P leaching into ground water without increasing the Al concentration of ground water.

  1. Histological Confirmation and Biological Significance of Cartilage Canals Demonstrated Using High Field MRI in Swine at Predilection Sites of Osteochondrosis

    PubMed Central

    Tóth, Ferenc; Nissi, Mikko J.; Zhang, Jinjin; Benson, Michael; Schmitter, Sebastian; Ellermann, Jutta M.; Carlson, Cathy S.

    2014-01-01

    Cartilage canal vessels in epiphyseal cartilage have a pivotal role in the pathogenesis of osteochondrosis/osteochondritis dissecans. The present study aimed to validate high field magnetic resonance imaging (MRI) methods to visualize these vessels in young pigs. Osteochondral samples from the distal femur and distal humerus (predilection sites of osteochondrosis) of piglets were imaged post-mortem: (1) using susceptibility-weighted imaging (SWI) in an MRI scanner, followed by histological evaluation; and (2) after barium perfusion using μCT, followed by clearing techniques. In addition, both stifle joints of a 25-day-old piglet were imaged in vivo using SWI and gadolinium enhanced T1-weighted MRI, after which distal femoral samples were harvested and evaluated using μCT and histology. Histological sections were compared to corresponding MRI slices, and three-dimensional visualizations of vessels identified using MRI were compared to those obtained using μCT and to the cleared specimens. Vessels contained in cartilage canals were identified using MRI, both ex vivo and in vivo; their locations matched those observed in the histological sections, μCT images, and cleared specimens of barium-perfused tissues. The ability to visualize cartilage canal blood vessels by MRI, without using a contrast agent, will allow future longitudinal studies to evaluate their role in developmental orthopedic disease. PMID:23939946

  2. Mars Hand Lens Imager (MAHLI) Efforts and Observations at the Rocknest Eolian Sand Shadow in Curiosity's Gale Crater Field Site

    NASA Technical Reports Server (NTRS)

    Edgett, K. S.; Yingst, R. A.; Minitti, M. E.; Goetz, W.; Kah, L. C.; Kennedy, M. R.; Lipkaman, L. J.; Jensen, E. H.; Anderson, R. C.; Beegle, L. W.; Carsten, J. L.; Cooper, B.; Deen, R. G.; Dromart, G.; Eigenbrode, J. L.; Grotzinger, J. P.; Gupta, S.; Hamilton, V. E.; Hardgrove, C. J.; Harker, D. E.; Herkenhoff, K. E.; Herrera, P. N.; Hurowitz, J. A.; Jandura, L.; Ming, D. W.

    2013-01-01

    The Mars Science Laboratory (MSL) mission is focused on assessing the past or present habitability of Mars, through interrogation of environment and environmental records at the Curiosity rover field site in Gale crater. The MSL team has two methods available to collect, process and deliver samples to onboard analytical laboratories, the Chemistry and Mineralogy instrument (CheMin) and the Sample Analysis at Mars (SAM) instrument suite. One approach obtains samples by drilling into a rock, the other uses a scoop to collect loose regolith fines. Scooping was planned to be first method performed on Mars because materials could be readily scooped multiple times and used to remove any remaining, minute terrestrial contaminants from the sample processing system, the Collection and Handling for In-Situ Martian Rock Analysis (CHIMRA). Because of this cleaning effort, the ideal first material to be scooped would consist of fine to very fine sand, like the interior of the Serpent Dune studied by the Mars Exploration Rover (MER) Spirit team in 2004 [1]. The MSL team selected a linear eolian deposit in the lee of a group of cobbles they named Rocknest (Fig. 1) as likely to be similar to Serpent Dune. Following the definitions in Chapter 13 of Bagnold [2], the deposit is termed a sand shadow. The scooping campaign occurred over approximately 6 weeks in October and November 2012. To support these activities, the Mars Hand Lens Imager (MAHLI) acquired images for engineering support/assessment and scientific inquiry.

  3. Field Calibration of Wind Direction Sensor to the True North and Its Application to the Daegwanryung Wind Turbine Test Sites

    PubMed Central

    Lee, Jeong Wan

    2008-01-01

    This paper proposes a field calibration technique for aligning a wind direction sensor to the true north. The proposed technique uses the synchronized measurements of captured images by a camera, and the output voltage of a wind direction sensor. The true wind direction was evaluated through image processing techniques using the captured picture of the sensor with the least square sense. Then, the evaluated true value was compared with the measured output voltage of the sensor. This technique solves the discordance problem of the wind direction sensor in the process of installing meteorological mast. For this proposed technique, some uncertainty analyses are presented and the calibration accuracy is discussed. Finally, the proposed technique was applied to the real meteorological mast at the Daegwanryung test site, and the statistical analysis of the experimental testing estimated the values of stable misalignment and uncertainty level. In a strict sense, it is confirmed that the error range of the misalignment from the exact north could be expected to decrease within the credibility level.

  4. UNRESOLVED MIXED POLARITY MAGNETIC FIELDS AT FLUX CANCELLATION SITE IN SOLAR PHOTOSPHERE AT 0.''3 SPATIAL RESOLUTION

    SciTech Connect

    Kubo, Masahito; Low, Boon Chye; Lites, Bruce W

    2014-09-20

    This is a follow-up investigation of a magnetic flux cancellation event at a polarity inversion line (PIL) on the Sun observed with the spectropolarimeter on board Hinode. Anomalous circular polarization (Stokes V) profiles are observed in the photosphere along the PIL at the cancellation sites. Kubo et al. previously reported that the theoretically expected horizontal fields between the canceling opposite-polarity magnetic elements in this event are not detected at granular scales. We show that the observed anomalous Stokes V profiles are reproduced successfully by adding the nearly symmetric Stokes V profiles observed at pixels immediately adjacent to the PIL. This result suggests that these observed anomalous Stokes V profiles are not indications of a flux removal process, but are the result of either a mixture of unresolved, opposite-polarity magnetic elements or the unresolved width of the PIL, at an estimated resolution element of about 0.''3. The hitherto undetected flux removal process accounting for the larger-scale disappearance of magnetic flux during the observing period is likely to also fall below resolution.

  5. Genotyping of Vibrio alginolyticus isolates from Daya Bay by infrequent-restriction-site PCR and pulsed-field gel electrophoresis.

    PubMed

    Ren, Chunhua; Hu, Chaoqun; Luo, Peng; Chen, Chang; Jiang, Xiao; Wang, Qingbai

    2008-08-01

    Vibrio alginolyticus is a serious bacterial pathogen that hampered the whole industry of fish farming in Guangdong, China. In order to facilitate epidemiologic studies and improve the control of disease, we developed a highly efficient method of genotyping for V. alginolyticus using infrequent-restriction-site PCR (IRS-PCR) technology. With the enzyme combination of NotI-HhaI, optimized, unique, and easy-to-interpret patterns were generated. Forty-five V. alginolyticus isolates from aquatic animals and the marine environment in Daya Bay in Guangdong were fingerprinted by IRS-PCR and pulsed-field gel electrophoresis (PFGE). The reproducibility of the IRS-PCR method was high (100%) in conformity with PFGE. When primer PN-T or PN-G was used, IRS-PCR obtained the identical clustering as PFGE, producing 24 different patterns, respectively. Moreover, IRS-PCR presented a high discriminatory power (D=0.953) identical to that of PFGE. In conclusion, the IRS-PCR fingerprinting method using NotI-HhaI can provide a potentially useful tool for epidemiologic investigations of V. alginolyticus isolates.

  6. Mauna Kea, Hawaii as an Analogue Site for Future Planetary Resource Exploration: Results from the 2010 ILSO-ISRU Field-Testing Campaign

    NASA Technical Reports Server (NTRS)

    ten Kate, I. L.; Armstrong, R.; Bernhardt, B.; Blummers, M.; Boucher, D.; Caillibot, E.; Captain, J.; Deleuterio, G.; Farmer, J. D.; Glavin, D. P.; Hamilton, J. C.; Klingelhoefer, G.; Morris, R. V.; Nunez, J. I.; Quinn, J. W.; Sanders, G. B.; Sellar, R. G.; Sigurdson, L.; Taylor, R.; Zacny, K.

    2010-01-01

    Within the framework of the International Lunar Surface Operation - In-Situ Resource Utilization Analogue Test held on January 27 - February 11, 2010 on the Mauna Kea volcano in Hawaii, a number of scientific instrument teams collaborated to characterize the field site and test instrument capabilities outside laboratory environments. In this paper, we provide a geological setting for this new field-test site, a description of the instruments that were tested during the 2010 ILSO-ISRU field campaign, and a short discussion for each instrument about the validity and use of the results obtained during the test. These results will form a catalogue that may serve as reference for future test campaigns. In this paper we provide a description and regional geological setting for a new field analogue test site for lunar resource exploration, and discuss results obtained from the 2010 ILSO-ISRU field campaign as a reference for future field-testing at this site. The following instruments were tested: a multispectral microscopic imager, MMI, a Mossbauer spectrometer, an evolved gas analyzer, VAPoR, and an oxygen and volatile extractor called RESOLVE. Preliminary results show that the sediments change from dry, organic-poor, poorly-sorted volcaniclastic sand on the surface, containing basalt, iron oxides and clays, to more water- and organic-rich, fine grained, well-sorted volcaniclastic sand, primarily consisting of iron oxides and depleted of basalt and clays. Furthermore, drilling experiments showed a very close correlation between drilling on the Moon and drilling at the test site. The ILSO-ISRU test site was an ideal location for testing strategies for in situ resource exploration at the lunar or martian surface.

  7. Realizing actual feedback control of complex network

    NASA Astrophysics Data System (ADS)

    Tu, Chengyi; Cheng, Yuhua

    2014-06-01

    In this paper, we present the concept of feedbackability and how to identify the Minimum Feedbackability Set of an arbitrary complex directed network. Furthermore, we design an estimator and a feedback controller accessing one MFS to realize actual feedback control, i.e. control the system to our desired state according to the estimated system internal state from the output of estimator. Last but not least, we perform numerical simulations of a small linear time-invariant dynamics network and a real simple food network to verify the theoretical results. The framework presented here could make an arbitrary complex directed network realize actual feedback control and deepen our understanding of complex systems.

  8. Divergence of actual and reference evapotranspiration observations for irrigated sugarcane with windy tropical conditions

    NASA Astrophysics Data System (ADS)

    Anderson, R. G.; Wang, D.; Tirado-Corbalá, R.; Zhang, H.; Ayars, J. E.

    2015-01-01

    Standardized reference evapotranspiration (ET) and ecosystem-specific vegetation coefficients are frequently used to estimate actual ET. However, equations for calculating reference ET have not been well validated in tropical environments. We measured ET (ETEC) using eddy covariance (EC) towers at two irrigated sugarcane fields on the leeward (dry) side of Maui, Hawaii, USA in contrasting climates. We calculated reference ET at the fields using the short (ET0) and tall (ETr) vegetation versions of the American Society for Civil Engineers (ASCE) equation. The ASCE equations were compared to the Priestley-Taylor ET (ETPT) and ETEC. Reference ET from the ASCE approaches exceeded ETEC during the mid-period (when vegetation coefficients suggest ETEC should exceed reference ET). At the windier tower site, cumulative ETr exceeded ETEC by 854 mm over the course of the mid-period (267 days). At the less windy site, mid-period ETr still exceeded ETEC, but the difference was smaller (443 mm). At both sites, ETPT approximated mid-period ETEC more closely than the ASCE equations ((ETPT-ETEC) < 170 mm). Analysis of applied water and precipitation, soil moisture, leaf stomatal resistance, and canopy cover suggest that the lower observed ETEC was not the result of water stress or reduced vegetation cover. Use of a custom-calibrated bulk canopy resistance improved the reference ET estimate and reduced seasonal ET discrepancy relative to ETPT and ETEC in the less windy field and had mixed performance in the windier field. These divergences suggest that modifications to reference ET equations may be warranted in some tropical regions.

  9. Modeling of 3d Space-time Surface of Potential Fields and Hydrogeologic Modeling of Nuclear Waste Disposal Sites

    NASA Astrophysics Data System (ADS)

    Shestopalov, V.; Bondarenko, Y.; Zayonts, I.; Rudenko, Y.

    extension and consolidation are identified. These data correlate with results of seismic and mining works. Hydrogeological 3D Model. The hydrogeological 3D Model de- velopment starts from the upper hydrodynamic zone, for which the data are available on hydraulic parameters. After calibration of the upper model elements, the deep part of the model is developed using data about the permeability structure of the crystalline rock massif, obtained from the 3D STSM. The results of analysis and the discrepancy of hydrodynamic regime modeling are used to refine the 3D Model for the rocks per- meability structure. This iterative process of consecutive correlation and refinement of model may be repeated many times. As a result of this technique implementation, the areas of active and very slow water exchange are found, and the system is revealed of vertically alternating zones of enhanced filtration and weak permeability. Based on these data, the sites are pre-selected, which are prospective for subsequently more detailed works on grounding the possibility of nuclear wastes isolation in geological formations. The use of the methodology described above is expedient at the stage of more detailed works, if the corresponding complex is provided of geophysical, hydro- geological, field testing and modeling investigations. Summary Successful testing of 3D STSM technology was carried out starting from 1997 till 1999 by the Ministry of Emergency Situations and Nuclear Safety of Ukraine during the realization of the project "Choosing the favorable geological structures for safe isolation of dangerous nuclear wastes of Chernobyl NPP". The performed works enabled us to draw prelim- inary 3D Space-Time Surface Model, structural-kinematic and geodynamic map of 2 the region understudy. As a result, two regions were selected, which are characterized by existence of geodynamic processes of cooling, thermal shrinkage and structural substance compression of geospace medium. Such regions seem to be the

  10. Understanding the ecological background of rice agriculture on the Ningshao Plain during the Neolithic Age: pollen evidence from a buried paddy field at the Tianluoshan cultural site

    NASA Astrophysics Data System (ADS)

    Li, Chunhai; Zheng, Yunfei; Yu, Shiyong; Li, Yongxiang; Shen, Huadong

    2012-03-01

    The progressive rise of atmospheric CH4 level since 5 ka has been hypothesized to result from human agricultural activities that turned forested lands, which would otherwise be a carbon sink, into paddy fields. Increasing numbers of Neolithic cultural sites unearthed in coastal eastern China, providing unique opportunities to test this hypothesis. Here, we present detailed pollen data from a buried paddy field at Tianluoshan cultural site on the Ningshao Plain, eastern China, to reconstruct the ecological conditions associated with the establishment of paddy fields. Stratigraphic data, radiocarbon ages, and pollen analyses show that vegetation underwent six phases of evolution and paddy fields were developed from 7000 to 4200 cal. yr BP. We found no evidence of slash-and-burn agriculture at the study site. Together with no presence of the irrigation system, our pollen data suggest the paddy fields at this site originated from wetlands. Hence, our findings do not support the hypothesis that anthropogenic-induced deforestation play ed a significant role in the rise of the atmospheric CH4 rise since the middle Holocene.

  11. Chemical Concentrations in Field Mice from Open-Detonation Firing Sites TA-36 Minie and TA-39 Point 6 at Los Alamos National Laboratory

    SciTech Connect

    Fresquez, Philip R.

    2011-01-01

    Field mice (mostly Peromyscus spp.) were collected at two open-detonation (high explosive) firing sites - Minie at Technical Area (TA) 36 and Point 6 at TA-39 - at Los Alamos National Laboratory in August of 2010 and in February of 2011 for chemical analysis. Samples of whole body field mice from both sites were analyzed for target analyte list elements (mostly metals), dioxin/furans, polychlorinated biphenyl congeners, high explosives, and perchlorate. In addition, uranium isotopes were analyzed in a composite sample collected from TA-36 Minie. In general, all constituents, with the exception of lead at TA-39 Point 6, in whole body field mice samples collected from these two open-detonation firing sites were either not detected or they were detected below regional statistical reference levels (99% confidence level), biota dose screening levels, and/or soil ecological chemical screening levels. The amount of lead in field mice tissue collected from TA-39 Point 6 was higher than regional background, and some lead levels in the soil were higher than the ecological screening level for the field mouse; however, these levels are not expected to affect the viability of the populations over the site as a whole.

  12. Developing Human Resources through Actualizing Human Potential

    ERIC Educational Resources Information Center

    Clarken, Rodney H.

    2012-01-01

    The key to human resource development is in actualizing individual and collective thinking, feeling and choosing potentials related to our minds, hearts and wills respectively. These capacities and faculties must be balanced and regulated according to the standards of truth, love and justice for individual, community and institutional development,…

  13. [Actual diet of patients with gastrointestinal diseases].

    PubMed

    Loranskaia, T I; Shakhovskaia, A K; Pavliuchkova, M S

    2000-01-01

    The study of actual nutrition of patients with erosive-ulcerative lesions in the gastroduodenal zone and of patients with operated ulcer has revealed defects in intake of essential nutrients by these patients: overeating of animal fat and refined carbohydrates, deficiency of oil, vitamins A, B2, C, D and food fibers.

  14. Humanistic Education and Self-Actualization Theory.

    ERIC Educational Resources Information Center

    Farmer, Rod

    1984-01-01

    Stresses the need for theoretical justification for the development of humanistic education programs in today's schools. Explores Abraham Maslow's hierarchy of needs and theory of self-actualization. Argues that Maslow's theory may be the best available for educators concerned with educating the whole child. (JHZ)

  15. Group Counseling for Self-Actualization.

    ERIC Educational Resources Information Center

    Streich, William H.; Keeler, Douglas J.

    Self-concept, creativity, growth orientation, an integrated value system, and receptiveness to new experiences are considered to be crucial variables to the self-actualization process. A regular, year-long group counseling program was conducted with 85 randomly selected gifted secondary students in the Farmington, Connecticut Public Schools. A…

  16. Teenagers' Perceived and Actual Probabilities of Pregnancy.

    ERIC Educational Resources Information Center

    Namerow, Pearila Brickner; And Others

    1987-01-01

    Explored adolescent females' (N=425) actual and perceived probabilities of pregnancy. Subjects estimated their likelihood of becoming pregnant the last time they had intercourse, and indicated the dates of last intercourse and last menstrual period. Found that the distributions of perceived probability of pregnancy were nearly identical for both…

  17. Removal of trace metals by Sorghum bicolor and Helianthus annuus in a site polluted by industrial wastes: a field experience.

    PubMed

    Marchiol, L; Fellet, G; Perosa, D; Zerbi, G

    2007-05-01

    Using the perspective of full scale application of phytoremediation techniques, research is focusing on the optimization of agronomic practices. Two annual high biomass yield crops, Sorghum bicolor and Helianthus annuus, were grown in a polymetallic soil. The experimental site, polluted by pyrite cinders, is located in an industrial site that has been listed in the clean-up national priority list since 2001. Specific aims of this work were to observe the concentration of metals in plants during the crop cycle and to establish the amount of metal removed by the crops. The field trial, arranged in a randomized block design, started in 2005. The concentrations of heavy metals in the soil were: As 309, Cd 4.29, Co 50.9, Cu 1527 and Zn 980mg kg(-1). The crops grown on the polluted soil received mineral fertilization (Fert) and organic amendment (Org), while plants in control soil (Ctrl) did not receive anything. The plots were watered during the crop cycle during two drought periods, using a sprinkler irrigation system. The phytoextraction potential of crops was estimated during the whole growth cycle and the plant biomass that was collected in each sampling date was ICP-analyzed. Plant-biomass growth curves were obtained. The concentrations of the metals in the shoots and in the total plant biomass were recorded. Finally, the metal removal was calculated for the harvestable parts of the crops. The amelioration of the nutritive status of the substrate that resulted, was highly effective for the biomass yield. However, fertilization and soil amendment did not heighten the concentration of metals in the harvestable tissue of the plants during the crop cycle. In some cases, organic matter appeared to bind the elements making them less available for the plants. The evaluation of the potential of phytoremediation of our plants compared to other crops in terms of metal removal was positive. Our results of metal removal are consistent with the results from other in situ

  18. Estimation of radioactive contamination of soils from the "Balapan" and the "Experimental field" technical areas of the Semipalatinsk nuclear test site.

    PubMed

    Evseeva, T; Belykh, E; Geras'kin, S; Majstrenko, T

    2012-07-01

    In spite of the long history of the research, radioactive contamination of the Semipalatinsk nuclear test site (SNTS) in the Republic of Kazakhstan has not been adequately characterized. Our cartographic investigation has demonstrated highly variable radioactive contamination of the SNTS. The Cs-137, Sr-90, Eu-152, Eu-154, Co-60, and Am-241 activity concentrations in soil samples from the "Balapan" site were 42.6-17646, 96-18250, 1.05-11222, 0.6-4865, 0.23-4893, and 1.2-1037 Bq kg(-1), correspondingly. Cs-137 and Sr-90 activity concentrations in soil samples from the "Experimental field" site were varied from 87 up to 400 and from 94 up to 1000 Bq kg(-1), respectively. Activity concentrations of Co-60, Eu-152, and Eu-154 were lower than the minimum detectable activity of the method used. Concentrations of naturally occurring radionuclides (K-40, Ra-226, U-238, and Th-232) in the majority of soil samples from the "Balapan" and the "Experimental field" sites did not exceed typical for surrounding of the SNTS areas levels. Estimation of risks associated with radioactive contamination based on the IAEA clearance levels for a number of key radionuclides in solid materials shows that soils sampled from the "Balapan" and the "Experimental field" sites might be considered as radioactive wastes. Decrease in specific activity of soil from the sites studied up to safety levels due to Co-60, Cs-137, Sr-90, Eu-152, Eu-154 radioactive decay and Am-241 accumulation-decay will occur not earlier than 100 years. In contrast, soils from the "Experimental field" and the "Balapan" sites (except 0.5-2.5 km distance from the "Chagan" explosion point) cannot be regarded as the radioactive wastes according safety norms valid in Russia and Kazakhstan.

  19. Investigation of hydrologic and biogeochemical controls on arsenic mobilization using distributed sensing at a field site in Munshiganj, Bangladesh

    NASA Astrophysics Data System (ADS)

    Ramanathan, N.; Estrin, D.; Harmon, T.; Harvey, C.; Jay, J.; Kohler, E.; Rothenberg, S.

    2006-12-01

    deployed in many habitat monitoring sensor networks. While using Sympathy at our Bangladesh field site we received 80% of the sensor data expected at the base station, upon returning, post-deployment analysis revealed that 42% of these sensor data were potentially faulty. Due to the remote location of the deployment, we were unable to go back and validate the questionable segments of the data set, forcing us to discard potentially interesting information. In addition to being undesirable, this response is often avoidable as well. Even simple actions such as checking sensor connections and quickly validating sensors in the field could have increased our confidence in the quality of the data, minimizing doubts that data observations were simply caused by badly behaving hardware. To improve data quality, we have designed a system called Confidence, which continuously monitors data collected at a base-station to identify faulty data and notify the user in the field of actions they can take to validate the data or remediate the sensor fault. Augmenting a sensor network deployment with Confidence and Sympathy enables users in the identification and remediation of faults impacting the quality and quantity of data respectively.

  20. Linking snow depth to avalanche release area size: measurements from the Vallée de la Sionne field site

    NASA Astrophysics Data System (ADS)

    Veitinger, Jochen; Sovilla, Betty

    2016-08-01

    One of the major challenges in avalanche hazard assessment is the correct estimation of avalanche release area size, which is of crucial importance to evaluate the potential danger that avalanches pose to roads, railways or infrastructure. Terrain analysis plays an important role in assessing the potential size of avalanche releases areas and is commonly based on digital terrain models (DTMs) of a snow-free summer terrain. However, a snow-covered winter terrain can significantly differ from its underlying, snow-free terrain. This may lead to different, and/or potentially larger release areas. To investigate this hypothesis, the relation between avalanche release area size, snow depth and surface roughness was investigated using avalanche observations of artificially triggered slab avalanches over a period of 15 years in a high-alpine field site. High-resolution, continuous snow depth measurements at times of avalanche release showed a decrease of mean surface roughness with increasing release area size, both for the bed surface and the snow surface before avalanche release. Further, surface roughness patterns in snow-covered winter terrain appeared to be well suited to demarcate release areas, suggesting an increase of potential release area size with greater snow depth. In this context, snow depth around terrain features that serve as potential delineation borders, such as ridges or trenches, appeared to be particularly relevant for release area size. Furthermore, snow depth measured at a nearby weather station was, to a considerable extent, related to potential release area size, as it was often representative of snow depth around those critical features where snow can accumulate over a long period before becoming susceptible to avalanche release. Snow depth - due to its link to surface roughness - could therefore serve as a highly useful variable with regard to potential release area definition for varying snow cover scenarios, as, for example, the avalanche

  1. Stochastic inversion of time-lapse geophysical data to characterize the vadose zone at the Arrenaes field site (Denmark)

    NASA Astrophysics Data System (ADS)

    Marie, S.; Irving, J. D.; Looms, M. C.; Nielsen, L.; Holliger, K.

    2011-12-01

    Geophysical methods such as ground-penetrating radar (GPR) can provide valuable information on the hydrological properties of the vadose zone. In particular, there is evidence to suggest that the stochastic inversion of such data may allow for significant reductions in uncertainty regarding subsurface van-Genuchten-Mualem (VGM) parameters, which characterize unsaturated hydrodynamic behaviour as defined by the combination of the water retention and hydraulic conductivity functions. A significant challenge associated with the use of geophysical methods in a hydrological context is that they generally exhibit an indirect and/or weak sensitivity to the hydraulic parameters of interest. A novel and increasingly popular means of addressing this issue involves the acquisition of geophysical data in a time-lapse fashion while changes occur in the hydrological condition of the probed subsurface region. Another significant challenge when attempting to use geophysical data for the estimation of subsurface hydrological properties is the inherent non-linearity and non-uniqueness of the corresponding inverse problems. Stochastic inversion approaches have the advantage of providing a comprehensive exploration of the model space, which makes them ideally suited for addressing such issues. In this work, we present the stochastic inversion of time-lapse zero-offset-profile (ZOP) crosshole GPR traveltime data, collected during a forced infiltration experiment at the Arreneas field site in Denmark, in order to estimate subsurface VGM parameters and their corresponding uncertainties. We do this using a Bayesian Markov-chain-Monte-Carlo (MCMC) inversion approach. We find that the Bayesian-MCMC methodology indeed allows for a substantial refinement in the inferred posterior parameter distributions of the VGM parameters as compared to the corresponding priors. To further understand the potential impact on capturing the underlying hydrological behaviour, we also explore how the posterior

  2. Potential Geophysical Field Transformations and Combined 3D Modelling for Estimation the Seismic Site Effects on Example of Israel

    NASA Astrophysics Data System (ADS)

    Eppelbaum, Lev; Meirova, Tatiana

    2015-04-01

    It is well-known that the local seismic site effects may have a significant contribution to the intensity of damage and destruction (e.g., Hough et al., 1990; Regnier et al., 2000; Bonnefoy-Claudet et al., 2006; Haase et al., 2010). The thicknesses of sediments, which play a large role in amplification, usually are derived from seismic velocities. At the same time, thickness of sediments may be determined (or defined) on the basis of 3D combined gravity-magnetic modeling joined with available geological materials, seismic data and borehole section examination. Final result of such investigation is a 3D physical-geological model (PGM) reflecting main geological peculiarities of the area under study. Such a combined study needs in application of a reliable 3D mathematical algorithm of computation together with advanced methodology of 3D modeling. For this analysis the developed GSFC software was selected. The GSFC (Geological Space Field Calculation) program was developed for solving a direct 3-D gravity and magnetic prospecting problem under complex geological conditions (Khesin et al., 1996; Eppelbaum and Khesin, 2004). This program has been designed for computing the field of Δg (Bouguer, free-air or observed value anomalies), ΔZ, ΔX, ΔY , ΔT , as well as second derivatives of the gravitational potential under conditions of rugged relief and inclined magnetization. The geological space can be approximated by (1) three-dimensional, (2) semi-infinite bodies and (3) those infinite along the strike closed, L.H. non-closed, R.H. on-closed and open). Geological bodies are approximated by horizontal polygonal prisms. The program has the following main advantages (besides abovementioned ones): (1) Simultaneous computing of gravity and magnetic fields; (2) Description of the terrain relief by irregularly placed characteristic points; (3) Computation of the effect of the earth-air boundary by the method of selection directly in the process of interpretation; (4

  3. Influence of external magnetic field and magnetic-site dilution on the magnetic dynamics of a one-dimensional Tb(III)-radical complex.

    PubMed

    Li, Leilei; Liu, Shuang; Li, Han; Shi, Wei; Cheng, Peng

    2015-07-11

    A new Tb(III)-radical chain complex was synthesized and characterized, which exhibited two separate relaxation processes. The influence of external magnetic field and magnetic-site dilution on the magnetic dynamics of a one-dimensional Tb(III)-radical complex was studied.

  4. Complete genome sequence of Cupriavidus basilensis 4G11, isolated from the Oak Ridge Field Research Center site

    SciTech Connect

    Ray, Jayashree; Waters, R. Jordan; Skerker, Jeffrey M.; Kuehl, Jennifer V.; Price, Morgan N.; Huang, Jiawen; Chakraborty, Romy; Arkin, Adam P.; Deutschbauer, Adam

    2015-05-14

    Cupriavidus basilensis 4G11 was isolated from groundwater at the Oak Ridge Field Research Center (FRC) site. Here, we report the complete genome sequence and annotation of Cupriavidus basilensis 4G11. The genome contains 8,421,483 bp, 7,661 predicted protein-coding genes, and a total GC content of 64.4%.

  5. Comparison of the effects of variable site temperatures and constant incubation temperatures on the biodegradation of petroleum hydrocarbons in pilot-scale experiments with field-aged contaminated soils from a cold regions site.

    PubMed

    Chang, Wonjae; Whyte, Lyle; Ghoshal, Subhasis

    2011-02-01

    Temporal atmospheric temperature changes during summers at sub-Arctic sites often cause periodic fluctuations in shallow landfarm and surface soil temperatures. However, little information is available on the effect of site-relevant variations on biodegradation performance in cold climates. This study compares the rate and extents of biodegradation of petroleum hydrocarbons at variable site temperatures (1-10 °C) representative of summers at a sub-Arctic site reported previously with those obtained under a constant average temperature of 6 °C. The biodegradation was evaluated in pilot-scale landfarming experiments with field-aged petroleum-contaminated soils shipped from Resolution Island (61°30'N, 65°00'W), Nunavut, Canada. Under the variable site temperature conditions biodegradation rate constants of semi- (F2) and non-volatile (F3) hydrocarbon fractions were enhanced by over a factor of two during the 60-d experiment, compared to the constant temperature mode. The decrease in total petroleum hydrocarbons (TPH) under the variable site temperature mode was 55% compared to only 19% under the constant average temperature mode. The enhanced biodegradation is attributable to the non-linear acceleration of microbial activity between 4.7 and 10°C and faster growth of indigenous hydrocarbon-degrading microbial populations. The first-order biodegradation rate constants of 0.018, 0.024 and 0.016 d(-1) for TPH, F2 and F3 fractions at the variable site temperature were in agreement with those determined by an on-site experiment at the same site.

  6. Microbiological, Geochemical and Hydrologic Processes Controlling Uranium Mobility: An Integrated Field-Scale Subsurface Research Challenge Site at Rifle, Colorado, Quality Assurance Project Plan

    SciTech Connect

    Fix, N. J.

    2008-01-07

    The U.S. Department of Energy (DOE) is cleaning up and/or monitoring large, dilute plumes contaminated by metals, such as uranium and chromium, whose mobility and solubility change with redox status. Field-scale experiments with acetate as the electron donor have stimulated metal-reducing bacteria to effectively remove uranium [U(VI)] from groundwater at the Uranium Mill Tailings Site in Rifle, Colorado. The Pacific Northwest National Laboratory and a multidisciplinary team of national laboratory and academic collaborators has embarked on a research proposed for the Rifle site, the object of which is to gain a comprehensive and mechanistic understanding of the microbial factors and associated geochemistry controlling uranium mobility so that DOE can confidently remediate uranium plumes as well as support stewardship of uranium-contaminated sites. This Quality Assurance Project Plan provides the quality assurance requirements and processes that will be followed by the Rifle Integrated Field-Scale Subsurface Research Challenge Project.

  7. Reproducing Actual Morphology of Planetary Lava Flows

    NASA Astrophysics Data System (ADS)

    Miyamoto, H.; Sasaki, S.

    1996-03-01

    Assuming that lava flows behave as non-isothermal laminar Bingham fluids, we developed a numerical code of lava flows. We take the self gravity effects and cooling mechanisms into account. The calculation method is a kind of cellular automata using a reduced random space method, which can eliminate the mesh shape dependence. We can calculate large scale lava flows precisely without numerical instability and reproduce morphology of actual lava flows.

  8. The Actual Apollo 13 Prime Crew

    NASA Technical Reports Server (NTRS)

    1970-01-01

    The actual Apollo 13 lunar landing mission prime crew from left to right are: Commander, James A. Lovell Jr., Command Module pilot, John L. Swigert Jr.and Lunar Module pilot, Fred W. Haise Jr. The original Command Module pilot for this mission was Thomas 'Ken' Mattingly Jr. but due to exposure to German measles he was replaced by his backup, Command Module pilot, John L. 'Jack' Swigert Jr.

  9. Determining Virtual Environment "Fit": The Relationship between Navigation Style in a Virtual Field Trip, Student Self-Reported Desire to Visit the Field Trip Site in the Real World, and the Purposes of Science Education

    ERIC Educational Resources Information Center

    Tutwiler, M. Shane; Lin, Ming-Chao; Chang, Chun-Yen

    2013-01-01

    In this study, a follow-up analysis of the data reported in Lin et al. ("Learn Media Technol." doi: 10.1080/17439884.2011.629660 , 2011), we investigated the relationship between student use of a virtual field trip (VFT) system and the probability of students reporting wanting to visit the national park site upon which the VFT was modeled,…

  10. Potential Geophysical Field Transformations and Combined 3D Modelling for Estimation the Seismic Site Effects on Example of Israel

    NASA Astrophysics Data System (ADS)

    Eppelbaum, Lev; Meirova, Tatiana

    2015-04-01

    It is well-known that the local seismic site effects may have a significant contribution to the intensity of damage and destruction (e.g., Hough et al., 1990; Regnier et al., 2000; Bonnefoy-Claudet et al., 2006; Haase et al., 2010). The thicknesses of sediments, which play a large role in amplification, usually are derived from seismic velocities. At the same time, thickness of sediments may be determined (or defined) on the basis of 3D combined gravity-magnetic modeling joined with available geological materials, seismic data and borehole section examination. Final result of such investigation is a 3D physical-geological model (PGM) reflecting main geological peculiarities of the area under study. Such a combined study needs in application of a reliable 3D mathematical algorithm of computation together with advanced methodology of 3D modeling. For this analysis the developed GSFC software was selected. The GSFC (Geological Space Field Calculation) program was developed for solving a direct 3-D gravity and magnetic prospecting problem under complex geological conditions (Khesin et al., 1996; Eppelbaum and Khesin, 2004). This program has been designed for computing the field of Δg (Bouguer, free-air or observed value anomalies), ΔZ, ΔX, ΔY , ΔT , as well as second derivatives of the gravitational potential under conditions of rugged relief and inclined magnetization. The geological space can be approximated by (1) three-dimensional, (2) semi-infinite bodies and (3) those infinite along the strike closed, L.H. non-closed, R.H. on-closed and open). Geological bodies are approximated by horizontal polygonal prisms. The program has the following main advantages (besides abovementioned ones): (1) Simultaneous computing of gravity and magnetic fields; (2) Description of the terrain relief by irregularly placed characteristic points; (3) Computation of the effect of the earth-air boundary by the method of selection directly in the process of interpretation; (4

  11. A field test for competitive effects of Aedes albopictus on A. aegypti in South Florida: differences between sites of coexistence and exclusion?

    PubMed Central

    Juliano, Steven A.; Lounibos, L. Philip; O’Meara, George F.

    2007-01-01

    We tested whether interspecific competition from Aedes albopictus had measurable effects on A. aegypti at the typical numbers of larval mosquitoes found in cemetery vases in south Florida. We also tested whether the effect of interspecific competition from A. albopictus on A. aegypti differed between sites where A. aegypti either persists or went extinct following invasion by A. albopictus. Similar experiments manipulating numbers of A. albopictus in cemetery vases were conducted at three sites of A. aegypti persistence and three sites where A. aegypti was apparently extinct. The experiments were done using numbers of larvae that were determined by observed numbers of larvae for each site, and with resources (leaf detritus) that accumulated in experimental vases placed into each field site. In both the early rainy season (when number of mosquito larvae was low) and the late rainy season (when number of mosquito larvae was high), there was a significant effect of treatment on developmental progress of experimental A. aegypti. In the late rainy season, when numbers of larvae were high, there was also a significant effect of treatment on survivorship of A. aegypti. However, the competition treatment × site type (A. aegypti persists vs extinct) interaction was never significant, indicating that the competitive effect of A. albopictus on A. aegypti did not differ systematically between persistence versus extinction sites. Thus, although competition from A. albopictus is strong under field conditions at all sites, we find no evidence that variation in the impact of interspecific competition is associated with coexistence or exclusion. Interspecific competition among larvae is thus a viable explanation for exclusion or reduction of A. aegypti in south Florida, but variation in the persistence of A. aegypti following invasion does not seem to be primarily a product of variation in the conditions in the aquatic environments of cemetery vases. PMID:15024640

  12. Comparison of Field Groundwater Biostimulation Experiments Using Polylactate and Lactate Solutions at the Chromium-Contaminated Hanford 100-H Site

    NASA Astrophysics Data System (ADS)

    Hazen, T. C.; Faybishenko, B.; Beller, H. R.; Brodie, E. L.; Sonnenthal, E. L.; Steefel, C.; Larsen, J.; Conrad, M. E.; Bill, M.; Christensen, J. N.; Brown, S. T.; Joyner, D.; Borglin, S. E.; Geller, J. T.; Chakraborty, R.; Nico, P. S.; Long, P. E.; Newcomer, D. R.; Arntzen, E.

    2011-12-01

    The primary contaminant of concern in groundwater at the DOE Hanford 100 Area (Washington State) is hexavalent chromium [Cr(VI)] in Hanford coarse-grained sediments. Three lactate injections were conducted in March, August, and October 2010 at the Hanford 100-H field site to assess the efficacy of in situ Cr(VI) bioreductive immobilization. Each time, 55 gal of lactate solution was injected into the Hanford aquifer. To characterize the biogeochemical regimes before and after electron donor injection, we implemented a comprehensive plan of groundwater sampling for microbial, geochemical, and isotopic analyses. These tests were performed to provide evidence of transformation of toxic and soluble Cr(VI) into less toxic and poorly soluble Cr(III) by bioimmobilization, and to quantify critical and interrelated microbial metabolic and geochemical mechanisms affecting chromium in situ reductive immobilization and the long-term sustainability of chromium bioremediation. The results of lactate injections were compared with data from two groundwater biostimulation tests that were conducted in 2004 and 2008 by injecting Hydrogen Release Compound (HRC°), a slow-release glycerol polylactate, into the Hanford aquifer. In all HRC and lactate injection tests, 13C-labeled lactate was added to the injected solutions to track post-injection carbon pathways. Monitoring showed that despite a very low initial total microbial density (from <104 to 105 cells/mL), both HRC and lactate injections stimulated anaerobic microbial activity, which led to an increase in biomass to >107 cells/mL (including sulfate- and nitrate-reducing bacteria), resulting in a significant decrease in soluble Cr(VI) concentrations to below the MCL. In all tests, lactate was consumed nearly completely within the first week, much faster than HRC. Modeling of biogeochemical and isotope fractionation processes with the reaction-transport code TOUGHREACT captured the biodegradation of lactate, fermentative production

  13. Laboratory and field studies related to radionuclide migration at the Nevada Test Site October 1, 1998-September 30, 1999

    SciTech Connect

    D. L. Finnegan; K. S. Kung; B. A. Martinez

    2000-02-01

    In this report the author describes his research in FY 1999 at the Nevada Test Site regarding the movement of radionuclides in groundwater. This work is funded by the US Department of Energy/Nevada Operations Office through their Defense Programs and Environmental Restorations divisions. Significant accomplishments include upgrading a spectrometer used to characterize groundwater colloids, acquisition of a probe to allow in situ measurement of groundwater parameters, and purchase of pumps for use in small-diameter access tubing. He collected water samples from a number of nuclear test sites during the past year. Samples from the chimney horizon at the Camembert site show that only volatile radionuclides are present there, as expected. Groundwater from the cavity region at the Cheshire site shows evidence of fission product leaching or desorption from melt glass or rock surfaces. Colloids present in this water were found to be remarkably stable during storage for many years. The colloid content of groundwater at the Cambric site and at UE-5n was found to be low relative to that in groundwater on Pahute Mesa. This, coupled with the apparent lack of groundwater flow in the alluvial rock at the Cambric site, suggests that radionuclide movement underground in this area is relatively minimal. He continued the yearly monitoring of the thermally hot cavity fluids at the Almendro site. He concludes this report by listing documents reviewed and presentations and publications generated by the program.

  14. HIGH RESOLTUION GEOELECTRICAL MEASUREMENTS OF BIODEGRADATION AND SURFACTANT REMEDIATION: LAB AND FIELD STUDES AND A NEW CHARACTERIZATION TEST CELL FIELD RESEARCH SITE

    EPA Science Inventory

    Laboratory and field high vertical resolution geophysical research has shown that geoelectrical measurements can detect and monitor the natural attenuation of petroleum hydrocarbons. These results have lead to the continued development and refinement of the conductive model for h...

  15. Air resistance measurements on actual airplane parts

    NASA Technical Reports Server (NTRS)

    Weiselsberger, C

    1923-01-01

    For the calculation of the parasite resistance of an airplane, a knowledge of the resistance of the individual structural and accessory parts is necessary. The most reliable basis for this is given by tests with actual airplane parts at airspeeds which occur in practice. The data given here relate to the landing gear of a Siemanms-Schuckert DI airplane; the landing gear of a 'Luftfahrzeug-Gesellschaft' airplane (type Roland Dlla); landing gear of a 'Flugzeugbau Friedrichshafen' G airplane; a machine gun, and the exhaust manifold of a 269 HP engine.

  16. Explosive Percolation Transition is Actually Continuous

    NASA Astrophysics Data System (ADS)

    da Costa, R. A.; Dorogovtsev, S. N.; Goltsev, A. V.; Mendes, J. F. F.

    2010-12-01

    Recently a discontinuous percolation transition was reported in a new “explosive percolation” problem for irreversible systems [D. Achlioptas, R. M. D’Souza, and J. Spencer, Science 323, 1453 (2009)SCIEAS0036-807510.1126/science.1167782] in striking contrast to ordinary percolation. We consider a representative model which shows that the explosive percolation transition is actually a continuous, second order phase transition though with a uniquely small critical exponent of the percolation cluster size. We describe the unusual scaling properties of this transition and find its critical exponents and dimensions.

  17. Comparison between theoretical footprint models and experimental measurements of intra-field spatial variability scalar fluxes over different sites

    NASA Astrophysics Data System (ADS)

    Masseroni, D.; Corbari, C.; Ceppi, A.; Milleo, G.; Mancini, M.

    2012-04-01

    Not many experimental data about intra-field spatial variability of scalar flux densities are presented in literature. In this work theoretical footprint models and experimental intra-field turbulent fluxes of latent, sensible heat and CO2 were compared. The experimental data were obtained using a mobile eddy covariance station moving it from a discontinuity point, represented by the field edge, to the centre of the field where a fixed eddy covariance station was placed. The experimental fields were in Landriano (PV) in the Po Valley, Italy and Barrax (Albacete) in Spain. Simple analytical footprint models that describe the representative source area for turbulent fluxes were compared with the experimental data. Mathematical relationship between footprint models and gamma function was explained. Energy balance closure was calculated starting from fixed tower measurements. Aerodynamic roughness and gamma distribution parameters were estimated for these specific fields.

  18. Mars Science Laboratory Curiosity rover initial Mastcam geomorphologic and multispectral characterization of the Gale crater field site

    NASA Astrophysics Data System (ADS)

    Bell, J. F.; Malin, M.; Maki, J.; Dietrich, W. E.; Edgett, K. S.; Edwards, L.; Garvin, J. B.; Hallet, B.; Herkenhoff, K. E.; Heydari, E.; Johnson, J. R.; Kah, L. C.; Lemmon, M. T.; Minitti, M.; Olson, T. S.; Parker, T. J.; Rice, M. S.; Rowland, S. K.; Schieber, J.; Sletten, R. S.; Sullivan, R. J.; Sumner, D. Y.; Thomas, P. C.; Yingst, R.; Team, M.

    2013-12-01

    The Mars Science Laboratory Curiosity rover landed in Gale crater on August 6, 2012 and has been enabling the exploration of a variety of geologic terrains between the rover's landing site at Bradbury Rise and the nearby topographic low point known as Yellowknife Bay. Curiosity carries a multispectral imaging system known as Mastcam, which consists of two boresighted CCD cameras, one of which acquires relatively wide field images (34-mm focal length, 18.4x15 degree FOV) and the other of which obtains narrower-angle telephoto images (100-mm focal length, 6.3x5.1 degree FOV). Each of these cameras has an 8-position filter wheel to enable imaging through broadband RGB Bayer filtes, nine specific narrowband filters in the 445 to 1012 nm region to enabled limited detectability of certain ferric, ferrous, and hydrated minerals, and neutral density solar filters for monitoring of atmospheric opacity. The Mastcams acquire images designed primarily to address specific scientific goals in geology, mineralogy, and atmospheric science, but also to support operational decisions related to rover driving, arm instrument placement, and rover subsystems status. Here we provide an overview of the initial scientific imaging results from the Mastcam investigation, from sol 0 (landing sol) through the end of the drilling campaign in Yellowknife Bay and the beginning of the long drive from there to the base of Mt. Sharp. A diversity of materials exposed at the surface have been encountered. This includes angular to sub-angular rock fragments scattered across the surface, boulder to fine gravel in size, variably dusty, and commonly fine grained. Thin outcrops of pebble to gravel conglomerate have been encountered across Bradbury rise. Granular ripples and other fine grained deposits were periodically encountered. In the wind-eroded Yellowknife Bay area, extensive polygonally fractured outcrops of sandstone and mudstone (with light-toned fracture fills) were discovered. The occurrence of

  19. Carrier redistribution between different potential sites in semipolar (202{sup ¯}1) InGaN quantum wells studied by near-field photoluminescence

    SciTech Connect

    Marcinkevičius, S.; Gelžinytė, K.; Zhao, Y.; Nakamura, S.; DenBaars, S. P.; Speck, J. S.

    2014-09-15

    Scanning near-field photoluminescence (PL) spectroscopy at different excitation powers was applied to study nanoscale properties of carrier localization and recombination in semipolar (202{sup ¯}1) InGaN quantum wells (QWs) emitting in violet, blue, and green-yellow spectral regions. With increased excitation power, an untypical PL peak energy shift to lower energies was observed. The shift was attributed to carrier density dependent carrier redistribution between nm-scale sites of different potentials. Near-field PL scans showed that in (202{sup ¯}1) QWs the in-plane carrier diffusion is modest, and the recombination properties are uniform, which is advantageous for photonic applications.

  20. Rocketdyne division, environmental monitoring and facility effluent. Annual report, De Soto and Santa Susana Field Laboratories Sites, 1986

    SciTech Connect

    Moore, J. D.

    1987-03-01

    Environmental and facility effluent radioactivity monitoring at the Rocketdyne Division of Rockwell International is performed by the Radiation and Nuclear Safety Group of the Health, Safety, and Environment Department. Soil and surface water are routinely sampled to a distance of 10 miles from Division sites. Ground water from site supply water wells and other test wells is periodically sampled to measure radioactivity in these waters. Continuous ambient air sampling and direct radiation monitoring by thermoluminescent dosimetry are performed at several on=site and off-site locations for measuring airborne radioactivity concentrations and site ambient radiation levels. Radioactivity in effluents discharged to the atmosphere from nuclear facilities is continuously sampled and monitored to ensure that amounts released to uncontrolled areas are below appropriate limits and to identify processes that may require additional engineering safeguards to minimize radioactivity in such discharges. In addition, selected nonradioactive chemical constituent concentrations in surface water discharged to uncontrolled areas are determined. The environmental radioactivity reported herein is attributed to natural sources, to local fallout of radioactive debris from the Chernobyl reactor accident, and to residual fallout of radioactive material from past atmospheric testing of nuclear devices.

  1. Rocketdyne division, environmental monitoring and facility effluent. Annual Report, De Soto and Santa Susana Field Laboratories Sites 1987

    SciTech Connect

    Moore, J. D.

    1988-03-01

    Environmental and facility effluent radioactivity monitoring at the Rocketdyne Division of Rockwell International is performed by the Radiation and Nuclear Safety Group of the Health, Safety, and Environment Department. Soil and surface water are routinely sampled to a distance of 10 miles from Division sites. Ground water from site supply water wells and other test wells is periodically sampled to measure radioactivity in these waters. Continuous ambient air sampling and direct radiation monitoring by thermoluminescent dosimetry are performed at several on-site and off-site locations for measuring airborne radioactivity concentrations and site ambient radiation levels. Radioactivity in effluents discharged to the atmosphere from nuclear facilities is continually sampled and monitored to ensure that amounts released to uncontrolled areas are below appropriate limited and to identify processes that rnay require additional engineering safeguards to minimize radioactivity in such discharges. In addition, selected nonradioactive chemical constituent concentrations in surface water discharged to uncontrolled areas are determined. The environmental radioactivity reported herein is attributed to natural sources and to residual fallout of radioactive material from past atmospheric testing of nuclear devices. Work in nuclear energy research and development in what has become the Rocketdyne Division of Rockwell International Corporation began in 1946. In addition to a broad spectrum of conventional programs in rocket propulsion, utilization of space, and national defense, Rocketdyne is working on the design, development, and testing of components and systems for central station nuclear power plants, the decladding of irradiated nuclear fuel, and the decontamination and decommissioning of facilities.

  2. Superfund record of decision (EPA Region 5): Petoskey Municipal Well Field Superfund Site, Petoskey, MI. (Interim Remedial Action), June 14, 1995

    SciTech Connect

    1996-02-01

    The Petoskey Municipal Well Field Site (the `Site`) is located in Petoskey, Michigan. The Site includes contaminated source area soils and the ground water that has been impacted by contaminants migrating from the source area. Ground water contamination has impacted the Ingalls Avenue Municipal Well (`Ingalls Well`) which is located on the shore of Lake Michigan and supplies water to residents of the City of Petoskey. Disposal of spent solvents and/or paint sludge on the ground surface outside the PMC building has contaminated soils and ground water in the vicinity of the source area. Water from the City of Petoskey`s Ingalls Well contains VOCs, including trichloroethene (TCE), and low levels of semi-volatile organic contaminants (SVOCs) and inorganic contaminants.

  3. Health assessment for Eau Claire Municipal Well Field National Priorities List (NPL) Site, Eau Claire, Wisconsin, Region 5. CERCLIS No. WID980820054. Final report

    SciTech Connect

    Not Available

    1989-04-17

    The Eau Claire Municipal Well Field NPL Site is located in the northwestern section of the City of Eau Claire, Wisconsin in northwest Eau Claire and southwest Chippewa Counties. The site supplies the drinking water for approximately 57,600 residents in the City of Eau Claire and Washington Township. The northern part of the well field site in Chippewa County exhibits some contamination by volatile organic compounds (VOCs) and semi-volatile organic compounds (semi-VOCs). Initial remedial actions resulted in the installation of an air-stripper to the municipal water supply to remove VOCs from the contaminated well ground waters. Investigations have indicated the presence of at least two plumes of ground water contamination, principally VOCs. The installation of an air-stripper on the municipal water supply has diminished the VOCs exposure by ingestion and inhalation for a large segment of the affected population. Chronic ingestion and inhalation of maximal levels of VOCs found in ground water at the Eau Claire Site may pose a potential public health hazard for private-well users.

  4. Energy levels and crystal-field parameters for Pr 3+ and Nd 3+ ions in rare earth (RE) tellurium oxides RE 2Te 4O 11 revisited - Ascent/descent in symmetry method applied for triclinic site symmetry

    NASA Astrophysics Data System (ADS)

    Karbowiak, M.; Rudowicz, C.; Gnutek, P.

    2011-06-01

    Triclinic site symmetry presents considerable challenges in the studies of energy levels and crystal-field parameters (CFPs) for rare earth (RE) ions in crystals. Assignment of the spectral features to the irreducible representations of low symmetry point groups is difficult and may be unreliable. Fittings of large number of CFPs, even if the number of the available experimental energy levels is sufficient, often yield multiple solutions with relatively low and close rms deviations. These challenges call for better methods of fitting and analysis of CFPs. In this paper, we employ the ascent/descent in symmetry (ADS) method and three computational approaches: (i) a crystallographic data analysis program to identify approximated higher symmetry, (ii) the superposition model (SPM) analysis, and (iii) the pseudosymmetry axes method (PAM) for the combined coordination factors obtained using SPM. As a case study, the experimental CF splittings of Pr 3+ and Nd 3+ ions at triclinic C 1 sites in tellurium oxides RE 2Te 4O 11 are re-analyzed. Two alternative ADS chains C 1 ↔ C 2 ↔ D 2 and C 1 ↔ C s ↔ C 2v were independently obtained. For each approximation of the actual C 1 symmetry of the REO 8 polyhedron in RE 2Te 4O 11, the ligands' positions are determined and used in SPM to calculate CFP sets, which are used as starting for additional fittings. Comparative analysis of the fitted and calculated CFP sets enables assignment of appropriate axis system to the fitted CFP sets, thus avoiding the ambiguities occurring in previous ADS applications. The very good compatibility and consistency of the newly determined CFP sets indicate high reliability of both approaches. These CFP sets were used to simulate magnetic susceptibility data for polycrystalline samples of Pr 2Te 4O 11 and Nd 2Te 4O 11. Wider applications of the proposed procedures in optical spectroscopy studies of low symmetry systems may improve reliability of the CFP sets reported in literature.

  5. The actual status of Astronomy in Moldova

    NASA Astrophysics Data System (ADS)

    Gaina, A.

    The astronomical research in the Republic of Moldova after Nicolae Donitch (Donici)(1874-1956(?)) were renewed in 1957, when a satellites observations station was open in Chisinau. Fotometric observations and rotations of first Soviet artificial satellites were investigated under a program SPIN put in action by the Academy of Sciences of former Socialist Countries. The works were conducted by Assoc. prof. Dr. V. Grigorevskij, which conducted also research in variable stars. Later, at the beginning of 60-th, an astronomical Observatory at the Chisinau State University named after Lenin (actually: the State University of Moldova), placed in Lozovo-Ciuciuleni villages was open, which were coordinated by Odessa State University (Prof. V.P. Tsesevich) and the Astrosovet of the USSR. Two main groups worked in this area: first conducted by V. Grigorevskij (till 1971) and second conducted by L.I. Shakun (till 1988), both graduated from Odessa State University. Besides this research areas another astronomical observations were made: Comets observations, astroclimate and atmospheric optics in collaboration with the Institute of the Atmospheric optics of the Siberian branch of the USSR (V. Chernobai, I. Nacu, C. Usov and A.F. Poiata). Comets observations were also made since 1988 by D. I. Gorodetskij which came to Chisinau from Alma-Ata and collaborated with Ukrainean astronomers conducted by K.I. Churyumov. Another part of space research was made at the State University of Tiraspol since the beggining of 70-th by a group of teaching staff of the Tiraspol State Pedagogical University: M.D. Polanuer, V.S. Sholokhov. No a collaboration between Moldovan astronomers and Transdniestrian ones actually exist due to War in Transdniestria in 1992. An important area of research concerned the Radiophysics of the Ionosphere, which was conducted in Beltsy at the Beltsy State Pedagogical Institute by a group of teaching staff of the University since the beginning of 70-th: N. D. Filip, E

  6. MODIS Solar Diffuser: Modelled and Actual Performance

    NASA Technical Reports Server (NTRS)

    Waluschka, Eugene; Xiong, Xiao-Xiong; Esposito, Joe; Wang, Xin-Dong; Krebs, Carolyn (Technical Monitor)

    2001-01-01

    The Moderate Resolution Imaging Spectroradiometer (MODIS) instrument's solar diffuser is used in its radiometric calibration for the reflective solar bands (VIS, NTR, and SWIR) ranging from 0.41 to 2.1 micron. The sun illuminates the solar diffuser either directly or through a attenuation screen. The attenuation screen consists of a regular array of pin holes. The attenuated illumination pattern on the solar diffuser is not uniform, but consists of a multitude of pin-hole images of the sun. This non-uniform illumination produces small, but noticeable radiometric effects. A description of the computer model used to simulate the effects of the attenuation screen is given and the predictions of the model are compared with actual, on-orbit, calibration measurements.

  7. 7 CFR 1437.101 - Actual production history.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 10 2014-01-01 2014-01-01 false Actual production history. 1437.101 Section 1437.101... Determining Yield Coverage Using Actual Production History § 1437.101 Actual production history. Actual production history (APH) is the unit's record of crop yield by crop year for the APH base period. The...

  8. 7 CFR 1437.101 - Actual production history.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 7 Agriculture 10 2012-01-01 2012-01-01 false Actual production history. 1437.101 Section 1437.101... Determining Yield Coverage Using Actual Production History § 1437.101 Actual production history. Actual production history (APH) is the unit's record of crop yield by crop year for the APH base period. The...

  9. 7 CFR 1437.101 - Actual production history.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 7 Agriculture 10 2011-01-01 2011-01-01 false Actual production history. 1437.101 Section 1437.101... Determining Yield Coverage Using Actual Production History § 1437.101 Actual production history. Actual production history (APH) is the unit's record of crop yield by crop year for the APH base period. The...

  10. 7 CFR 1437.101 - Actual production history.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 10 2013-01-01 2013-01-01 false Actual production history. 1437.101 Section 1437.101... Determining Yield Coverage Using Actual Production History § 1437.101 Actual production history. Actual production history (APH) is the unit's record of crop yield by crop year for the APH base period. The...

  11. 7 CFR 1437.101 - Actual production history.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Actual production history. 1437.101 Section 1437.101... Determining Yield Coverage Using Actual Production History § 1437.101 Actual production history. Actual production history (APH) is the unit's record of crop yield by crop year for the APH base period. The...

  12. Alternate corrections for estimating actual wetland evapotranspiration from potential evapotranspiration

    USGS Publications Warehouse

    Barclay, Shoemaker W.; Sumner, D.M.

    2006-01-01

    Corrections can be used to estimate actual wetland evapotranspiration (AET) from potential evapotranspiration (PET) as a means to define the hydrology of wetland areas. Many alternate parameterizations for correction coefficients for three PET equations are presented, covering a wide range of possible data-availability scenarios. At nine sites in the wetland Everglades of south Florida, USA, the relatively complex PET Penman equation was corrected to daily total AET with smaller standard errors than the PET simple and Priestley-Taylor equations. The simpler equations, however, required less data (and thus less funding for instrumentation), with the possibility of being corrected to AET with slightly larger, comparable, or even smaller standard errors. Air temperature generally corrected PET simple most effectively to wetland AET, while wetland stage and humidity generally corrected PET Priestley-Taylor and Penman most effectively to wetland AET. Stage was identified for PET Priestley-Taylor and Penman as the data type with the most correction ability at sites that are dry part of each year or dry part of some years. Finally, although surface water generally was readily available at each monitoring site, AET was not occurring at potential rates, as conceptually expected under well-watered conditions. Apparently, factors other than water availability, such as atmospheric and stomata resistances to vapor transport, also were limiting the PET rate. ?? 2006, The Society of Wetland Scientists.

  13. Floodplain/wetlands assessment for the interceptor trench field study near the Weldon Spring Quarry, Weldon Spring Site, Missouri

    SciTech Connect

    Van Lonkhuyzen, R.A.

    1999-12-15

    The US Department of Energy proposes to construct a groundwater interceptor trench near the Weldon Spring Quarry at the Weldon Spring Site in Missouri. The trench would be located near two palustrine wetland areas. Impacts to wetland hydrology and biotic communities are expected to be negligible. No long-term adverse impacts to floodplains are expected.

  14. Technical procedures for water resources: Volume 4, Deaf Smith County site, Texas: Environmental Field Program: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    This volume contains Technical Procedures pursuant to the water Resources Site Study Plan: including Collection, Preservation, and Shipment of Ground-Water Samples; Inventory Current Water Use and Estimating Projected Water Use; Estimation of Precipitation Depth, Duration, Frequence; Estimation of Probable Maximum Precipitation; Calculation of Floodplains.

  15. Technical procedures for water resources, Deaf Smith County site, Texas: Volume 1: Environmental Field Program: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    This volume contains Technical Procedures pursuant to the Water Resources Site Study Plan including, determination of basin topographic characteristics, determination of channel and playa lake characteristics, operation of a stream gaging station, operation of a playa lake stage gaging system, and processing of data from a playa lake stage gaging system.

  16. Investigating temporal field sampling strategies for site-specific calibration of three soil moisture - neutron flux interaction models

    NASA Astrophysics Data System (ADS)

    Iwema, Joost; Rosolem, Rafael; Baatz, Roland; Wagener, Thorsten; Bogena, Heye

    2015-04-01

    Soil moisture is an important state variable in land-atmosphere interaction and hydrological processes. The novel Cosmic-Ray Neutron Sensor (CRNS) can be used to determine soil moisture at the sub-kilometre scale, which is relevant to these processes. The CRNS is usually calibrated with soil moisture samples taken on a single day. We investigated whether using data from only one day can be sufficient and, if not, how many days would be needed to obtain a reliable calibration. Therefore temporal sampling strategies for calibration of three widely used soil moisture - cosmic-ray neutron interaction models were investigated for three distinct sites: an arid site in Arizona (USA), a temperate humid grassland and a temperate humid spruce forest, both located in Germany. First, the effects of the number of sampling days on the calibration results were analysed and the effects of different soil wetness conditions of the sampling days on the quality of the calibration results were then investigated. Independent point-scale (TDT) soil moisture measurements from a sensor network were used as input to all three models. Simulated neutron intensity was then compared against measurements from cosmic-ray sensors at all sites. It was found that, if wetness conditions were not taken into account, collecting soil moisture samples on more than one day is needed to obtain a reliable calibration result, regardless of which model is used. We typically find that two to four days are normally sufficient. Sampling on days or combinations of days with appropriate wetness conditions for specific sites can reduce the needed number of sampling days. What appropriate wetness conditions are, differs between sites and different soil moisture - cosmic-ray neutron interaction models.

  17. Comparison of three field screening techniques for delineating petroleum hydrocarbon plumes in groundwater at a site in the southern Carson Desert, Nevada

    SciTech Connect

    Smuin, D.R.

    1993-01-01

    Three types of field screening techniques used in the characterization of potentially contaminated sites at Naval Air Station Fallon, Nevada, are compared. The methods and results for each technique are presented. The three techniques include soil-gas surveys, electromagnetic geophysical surveys, and groundwater test hole screening. Initial screening at the first study site included two soil-gas surveys and electromagnetic geophysical studies. These screening methods identified I areas of contamination; however, results were inconclusive. Therefore groundwater test hole screening was performed. Groundwater screening consisted of auger drilling down to the shallow alluvial aquifer. Groundwater samples were collected from the open drill hole with a bailer. On-site head-space analyses for volatile organic compounds (VOCS) were performed using a portable gas chromatograph (GC). Five areas of floating petroleum hydrocarbon product were identified along with the overall dissolved contaminant plume boundaries. Well placement was re-evaluated, and well sites were relocated based on the screening information. The most effective technique for identification of petroleum hydrocarbon-contaminant plumes was groundwater test hole screening. Groundwater screening was subsequently performed at 19 other sites. A total of 450 test holes were analyzed resulting in the delineation of six plumes.

  18. Variations and constancy of mercury and methylmercury accumulation in rice grown at contaminated paddy field sites in three Provinces of China.

    PubMed

    Li, B; Shi, J B; Wang, X; Meng, M; Huang, L; Qi, X L; He, B; Ye, Z H

    2013-10-01

    Many paddy fields have been contaminated by mercury (Hg) in mining areas of China. In this study, twenty-six rice cultivars and three Hg contaminated paddy fields in different geographic regions were selected for field trials and aimed to investigate the variations and similarities in total Hg (THg) and methylmercury (MeHg) accumulations in brown rice (seeds) across sites. Our results revealed widescale cultivar variation in THg (13-52 ng g(-1) at Wanshan) and MeHg (3.5-23 ng g(-1)) accumulation and %MeHg (17.7-89%) in seeds. The ability to translocate is an important factor in the levels of THg and MeHg in seed. Cultivar tended to stability in THg accumulation across sites. Some cultivars accumulated lower concentrations of both THg and MeHg in seeds at fields seriously contaminated by Hg. Present results suggest that appropriate cultivar selection is a possible way to reduce THg and MeHg accumulation in seeds of rice grown in Hg-contaminated regions.

  19. What Does Ratemyprofessors.com Actually Rate?

    ERIC Educational Resources Information Center

    Clayson, Dennis E.

    2014-01-01

    This research looks closely at claims that ratemyprofessors.com creates a valid measure of teaching effectiveness because student responses are consistent with a learning model. While some evidence for this contention was found in three datasets taken from the site, the majority of the evidence indicates that the instrument is biassed by a halo…

  20. The Intensity of the Geomagnetic Field During the Last 6 Millennia as Recorded by Slag Deposits From Archaeological Sites in the Southern Levant

    NASA Astrophysics Data System (ADS)

    Ben-Yosef, E.; Tauxe, L.; Hagai, R.; Agnon, A.; Levy, T.; Avner, U.; Kessel, R.; Najjar, M.; Holtzer, A.; Steindorf, J.

    2005-12-01

    Copper-slag material from archaeological sites is a novel and highly promising medium to be used in paleointensity experiments. Its magnetization is carried by ultra fine grained magnetite and was acquired during fast cooling, often behaving nearly ideally during the paleointensity experiment. One of the richest archaeometallurgical regions in the eastern Mediterranean is located in the southern Levant, straddling the `Arava valley, the natural border between the modern states of Israel and Jordan. Metalworking activities cover a time span of more than six thousands years, beginning in the 5th millennium B.C., a date that coincides with innovations in metallurgy in many parts of the Old World. Here we will present results from 77 copper-slag samples from 28 archaeometallurgical sites from the `Arava valley plus several from other locations in Israel. We employed the alternating Infield-Zero field/Zero-field infield (IZZI) cooling method of Yu et al. 2004 on up to 10 specimens from each sample. We also performed anisotropy of anhysteretic remenance experiments. Using strict data selection criteria, 35 samples yielded acceptable results for about a 45% success rate. Moreover, we re-melted slag material and cooled it by exposure to laboratory air in a known field. The intensity results of this re-melted slag recovered the applied field lending confidence to the archaeointensity results. The data gained hitherto shows a fluctuating field behavior, with relatively low field intensity during the 6th millennium B.P. and a conspicuous peak around 3,000 B.P. These trends agree with the global world-model of Korte and Constable (2004), and are in excellent agreement with data from northern Syria (Genevey et al. 2003). Finally, we obtained results from archaeological sites with poor or disputed dating. These results suggest that certain localities were used over a long period of time, potentially reconciling the age disputes amongst archaeologists. Genevey, A.; Gallet, Y

  1. Fluid Geochemistry of the Capelinhos Vent Site. A Key to Understand the Lucky Strike Hydrothermal Vent Field (37°N, MAR).

    NASA Astrophysics Data System (ADS)

    Leleu, T.; Chavagnac, V.; Cannat, M.; Ceuleneer, G.; Castillo, A.; Menjot, L.

    2015-12-01

    The Lucky Strike hydrothermal field is situated at the mid-Atlantic ridge, south of the Azores, on top of a central volcano within the axial valley. The volcano is composed of a fossil lava lake surrounded by three volcanic cones. An Axial Magma Chamber (AMC) is reported 3.4km below the seafloor. The active venting sites are situated around the fossil lava lake and are directly linked to the heat supplied by the AMC. High temperature fluids from the Lucky Strike field were sampled in 2013, 2014 and 2015 in order to document the depth of the reaction zone, subsurface mixing, geographical control and magmatic degassing. A new active site named Capelinhos was discovered approximately 1.5km eastward from the lava lake, during exploration by ROV Victor6000 - MoMARsat cruise, 2013. It is composed of 10m-high chimneys discharging black smoker-type fluid. Fluid temperatures were 328°C in 2013 and decreased to 318°C in 2014 and 2015. Capelinhos fluids are Cl-depleted by 55% compared to seawater indicating phase separation at depth. In comparison, the other sites range from 6% enrichment (2608/Y3 site) to 22% depletion (Eiffel tower site). Si geothermobarometry of Y3 site estimates quartz equilibration at P=300 bars and T=360-380°C, coherent with Fe/Mn geothermometer (T=370±10°C). For Capelinhos, Fe/Mn suggests 398°C (±10°C) which is close to the critical point of seawater (P=300 bars and T=407°C). Other geothermobarometer uses Si/Cl vapor-like fluid to constrain depth of the top of reaction zone and predicts significant bias due to mixing along the up-flow zone. Application gives P=~370 bars, T=~435°C at Capelinhos and P=~390 bars, T=~440°C at Eiffel tower. This is further sustained by end-member 87Sr/86Sr=0.7038, which indicates little interaction of Capelinhos vent fluids with seawater-derived fluid, compared to other vapor-like sites with 87Sr/86Sr=0.7043. Because of its external location, Capelinhos site isn't influenced by the complex tectonic context of the

  2. INTEGRAL FIELD SPECTROSCOPY OF SUPERNOVA EXPLOSION SITES: CONSTRAINING THE MASS AND METALLICITY OF THE PROGENITORS. I. TYPE Ib AND Ic SUPERNOVAE

    SciTech Connect

    Kuncarayakti, Hanindyo; Maeda, Keiichi; Doi, Mamoru; Morokuma, Tomoki; Hashiba, Yasuhito; Aldering, Greg; Arimoto, Nobuo; Pereira, Rui

    2013-08-01

    Integral field spectroscopy of 11 Type Ib/Ic supernova (SN Ib/Ic) explosion sites in nearby galaxies has been obtained using UH88/SNIFS and Gemini-N/GMOS. The use of integral field spectroscopy enables us to obtain both spatial and spectral information about the explosion site, enabling the identification of the parent stellar population of the SN progenitor star. The spectrum of the parent population provides metallicity determination via strong-line method and age estimation obtained via comparison with simple stellar population models. We adopt this information as the metallicity and age of the SN progenitor, under the assumption that it was coeval with the parent stellar population. The age of the star corresponds to its lifetime, which in turn gives the estimate of its initial mass. With this method we were able to determine both the metallicity and initial (zero-age main sequence) mass of the progenitor stars of SNe Ib and Ic. We found that on average SN Ic explosion sites are more metal-rich and younger than SN Ib sites. The initial mass of the progenitors derived from parent stellar population age suggests that SN Ic has more massive progenitors than SN Ib. In addition, we also found indication that some of our SN progenitors are less massive than {approx}25 M{sub Sun }, indicating that they may have been stars in a close binary system that have lost their outer envelope via binary interactions to produce SNe Ib/Ic, instead of single Wolf-Rayet stars. These findings support the current suggestions that both binary and single progenitor channels are in effect in producing SNe Ib/Ic. This work also demonstrates the power of integral field spectroscopy in investigating SN environments and active star-forming regions.

  3. [Measurement and data analysis of drug concentrations at the target site--potentials, limitations and fields of application].

    PubMed

    Schäftlein, André; el Talia, Maurice; Kloft, Charlotte

    2013-04-01

    Drug measurements in the blood are only surrogates for drug concentrations in peripheral tissues, which often represent the target sites of the drug. Due to drug specific and physiological characteristics, however, blood and target site concentrations may differ. For this reason, methods to measure drug concentrations at the target site have been developed during the last years. During the last decade, microdialysis has become the method of choice for the continuous study of unbound tissue concentrations of drugs. In order to fully exploit these measurements to quantify the concentration-time profile of the investigated drug, different tools of data analysis can be applied. The aim is to contribute to decision-making in selecting the optimal dose 1) for dosing schedules during the development program of new drugs and 2) for therapeutic usage for physicians and pharmacists. For these aims, the so called ,,nonlinear mixed effect (NLME) modelling approach" presents the method of choice as it determines the typical concentration-time profile of a drug as well as the variability within the investigated study population. Additionally, between-patient variability can be explained by patient-specific characteristics e.g. weight enabling dose individualisation within the whole investigated population. A systematic literature research in Pubmed for the use of antiinfectives in humans shows that the preferable methods of measuring concentrations at the target site (microdialysis) and data analysis (NLME) have rarely been used simultaneously. Hence, in future the benefit of linking both methods of choice should be further exploited in order to improve knowledge gain, to optimise antiinfective dosing regimens and to increase medication safety.

  4. Grouted support plates in reactor buildings at the Savannah River Site: Field investigation, tests, and seismic evaluation

    SciTech Connect

    Joshi, J.R.; Maryak, M.E.

    1991-12-31

    The Westinghouse Savannah River Company (WSRC) conducted a seismic evaluation of the grouted support plates in the reactor buildings at the Savannah River Site (SRS) in response to issues raised from an earlier analysis. Researchers conducted the tests in a reactor building that was no longer in use and transferred the results to other reactor buildings. This paper discusses tests, results, analysis, and modifications made to achieve seismic qualification. 4 refs.

  5. Grouted support plates in reactor buildings at the Savannah River Site: Field investigation, tests, and seismic evaluation

    SciTech Connect

    Joshi, J.R.; Maryak, M.E.

    1991-01-01

    The Westinghouse Savannah River Company (WSRC) conducted a seismic evaluation of the grouted support plates in the reactor buildings at the Savannah River Site (SRS) in response to issues raised from an earlier analysis. Researchers conducted the tests in a reactor building that was no longer in use and transferred the results to other reactor buildings. This paper discusses tests, results, analysis, and modifications made to achieve seismic qualification. 4 refs.

  6. Pilot-scale field tests for the methanotrophic technology cometabolic bioreactor demonstration at the Oak Ridge K-25 Site

    SciTech Connect

    Donaldson, T.L.; Lucero, A.J.; Jennings, H.L.; Herbes, S.E.

    1993-06-01

    This report describes a demonstration of cometabolic technology for bioremediation of groundwater contaminated with trichloroethylene (TCE) and other chlorinated and aromatic solvents conducted by Oak Ridge National Laboratory (ORNL). The technology demonstration is located at a seep from the K-1070-C/D Classified Burial Ground at the Oak Ridge K-25 Site. Funding for this demonstration is provided by the US Department of Energy (DOE), Environmental Restoration/Waste Management Program, Office of Technology Development.

  7. Microbial Diversity and Metal Speciation Changes in Mine Tailings Following Compost-Assisted Direct Planting: A Four-Year Superfund Site Field Study

    NASA Astrophysics Data System (ADS)

    Maier, R. M.; Gil-Loaiza, J.; Honeker, L. K.; Hottenstein, J. D.; Valentin-Vargas, A.; Jennings, L. L.; Hammond, C.; Neilson, J. W.; Root, R. A.; Chorover, J.

    2015-12-01

    EPA estimates that future mine tailings remediation costs will exceed US $50 billion using present technologies based on constructing an inert or biological cap on the tailings. Both approaches require large amounts of capping materials that can be difficult and expensive to obtain especially for sites several thousand hectares in size. An alternative technology is direct planting into tailings. However, direct planting alone is not feasible for many legacy sites due to extreme acidity and high metal content which prevent plant germination and growth. Therefore the process must be "assisted" through the addition of amendments such as compost. Here we present results from the first four years of a field study at the Iron King Mine and Humboldt Smelter Superfund site demonstrating the feasibility of compost-assisted direct planting. Parameters measured during the field study included: canopy cover, pH, nutrient content, plant metal uptake, metal(loid) speciation, mineral analysis, microbiome analysis, and plant root-metal-microbe interactions. Integrated analysis of these parameters suggests that even in this "worst-case scenario" mine tailings site (pH 2.5; As and Pb each exceeding 2 g kg-1), we have created a sustainable system. In this system, phyto-catalyzed stabilization of inorganic contaminants in the root zone is driven by plant root exudates and the associated rhizosphere microbial community. The results of this research will be put into context of a larger topic- that of ecological engineering of mine tailings sites - a technique being proposed to prevent creation of acidic conditions and metal(loid) mobilization in the first place.

  8. Microbial Diversity and Metal Speciation Changes in Mine Tailings Following Compost-Assisted Direct Planting: A Four-Year Superfund Site Field Study

    NASA Astrophysics Data System (ADS)

    Maier, R. M.; Gil-Loaiza, J.; Honeker, L. K.; Hottenstein, J. D.; Valentin-Vargas, A.; Jennings, L. L.; Hammond, C.; Neilson, J. W.; Root, R. A.; Chorover, J.

    2014-12-01

    EPA estimates that future mine tailings remediation costs will exceed US $50 billion using present technologies based on constructing an inert or biological cap on the tailings. Both approaches require large amounts of capping materials that can be difficult and expensive to obtain especially for sites several thousand hectares in size. An alternative technology is direct planting into tailings. However, direct planting alone is not feasible for many legacy sites due to extreme acidity and high metal content which prevent plant germination and growth. Therefore the process must be "assisted" through the addition of amendments such as compost. Here we present results from the first four years of a field study at the Iron King Mine and Humboldt Smelter Superfund site demonstrating the feasibility of compost-assisted direct planting. Parameters measured during the field study included: canopy cover, pH, nutrient content, plant metal uptake, metal(loid) speciation, mineral analysis, microbiome analysis, and plant root-metal-microbe interactions. Integrated analysis of these parameters suggests that even in this "worst-case scenario" mine tailings site (pH 2.5; As and Pb each exceeding 2 g kg-1), we have created a sustainable system. In this system, phyto-catalyzed stabilization of inorganic contaminants in the root zone is driven by plant root exudates and the associated rhizosphere microbial community. The results of this research will be put into context of a larger topic- that of ecological engineering of mine tailings sites - a technique being proposed to prevent creation of acidic conditions and metal(loid) mobilization in the first place.

  9. New observations of infiltration through fractured alluvium in Yucca Flat, Nevada Test Site: A preliminary field investigation

    SciTech Connect

    Kao, C.S.; Smith, D.K.; McKinnis, W.B.

    1994-02-01

    Regional tectonics coupled with the subsurface detonation of nuclear explosives has caused widespread fracturing of the alluvium of Yucca Flat. Fractures deeper than 30 meters have been observed in boreholes. Some of these fractures are large enough to capture significant amounts of runoff during storm events. Evidence of stream capture by fractures and observations of runoff flowing into open fractures give qualitative evidence of infiltration to depths greater than several meters and possibly to the saturated zone. Our field observations contradict the assumption that little infiltration occurs on Yucca Flat. The larger, hydrologically important fractures are associated with geologic faults or the regional stress field. Additional field studies are needed to investigate the impact of fractures on the transport of contaminants.

  10. Application of ERTS-1 imagery in the fields of geology, agriculture, forestry, and hydrology to selected test sites in Iran

    NASA Technical Reports Server (NTRS)

    Ebtehadj, K.

    1973-01-01

    The preliminary study of the ERTS-1 imagery coverage of Iran, commenced on October 26, 1972. All of the images were carefully examined, and a photomosaic covering approximately ninety-five per cent of the country was prepared. A number of images of selected areas were studied in detail. In the field of geology, a number of large scale faults were identified, which do not figure on geological maps. Furthermore, a preliminary study was carried out on the recent sediments, their possible sources, and origin. A limited number of geological work maps were prepared as well. In the fields of agriculture and forestry, studies based on color composite prints of certain areas were undertaken, with a purpose of identifying potential arable areas. Investigations in the field of water resources resulted in the discovery of a number of small lakes, and streams. Furthermore, fluctuations of the water level in some lakes were observed.

  11. The nonrelativistic limit of (central-extended) Poincare group and some consequences for quantum actualization

    SciTech Connect

    Ardenghi, Juan S.; Castagnino, M.; Campoamor-Stursberg, R.

    2009-10-15

    The nonrelativistic limit of the centrally extended Poincare group is considered and their consequences in the modal Hamiltonian interpretation of quantum mechanics are discussed [O. Lombardi and M. Castagnino, Stud. Hist. Philos. Mod. Phys 39, 380 (2008); J. Phys, Conf. Ser. 128, 012014 (2008)]. Through the assumption that in quantum field theory the Casimir operators of the Poincare group actualize, the nonrelativistic limit of the latter group yields to the actualization of the Casimir operators of the Galilei group, which is in agreement with the actualization rule of previous versions of modal Hamiltonian interpretation [Ardenghi et al., Found. Phys. (submitted)].

  12. Ultra-high field NMR studies of antibody binding and site-specific phosphorylation of {alpha}-synuclein

    SciTech Connect

    Sasakawa, Hiroaki |; Sakata, Eri; Yamaguchi, Yoshiki; Masuda, Masami |; Mori, Tetsuya; Kurimoto, Eiji; Iguchi, Takeshi; Hisanaga, Shin-ichi; Iwatsubo, Takeshi; Hasegawa, Masato; Kato, Koichi |

    2007-11-23

    Although biological importance of intrinsically disordered proteins is becoming recognized, NMR analyses of this class of proteins remain as tasks with more challenge because of poor chemical shift dispersion. It is expected that ultra-high field NMR spectroscopy offers improved resolution to cope with this difficulty. Here, we report an ultra-high field NMR study of {alpha}-synuclein, an intrinsically disordered protein identified as the major component of the Lewy bodies. Based on NMR spectral data collected at a 920 MHz proton frequency, we performed epitope mapping of an anti-{alpha}-synuclein monoclonal antibody, and furthermore, characterized conformational effects of phosphorylation at Ser129 of {alpha}-synuclein.

  13. Field study site selection, species abundance and monthly distribution of anopheline mosquitoes in the northern Kruger National Park, South Africa

    PubMed Central

    2014-01-01

    Background Knowledge of the ecology and behaviour of a target species is a prerequisite for the successful development of any vector control strategy. Before the implementation of any strategy it is essential to have comprehensive information on the bionomics of species in the targeted area. The aims of this study were to conduct regular entomological surveillance and to determine the relative abundance of anopheline species in the northern Kruger National Park. In addition to this, the impact of weather conditions on an Anopheles arabiensis population were evaluated and a range of mosquito collection methods were assessed. Methods A survey of Anopheles species was made between July 2010 and December 2012. Mosquitoes were collected from five sites in the northern Kruger National Park, using carbon dioxide-baited traps, human landing and larval collections. Specimens were identified morphologically and polymerase chain reaction assays were subsequently used where appropriate. Results A total of 3,311 specimens belonging to nine different taxa was collected. Species collected were: Anopheles arabiensis (n = 1,352), Anopheles quadriannulatus (n = 870), Anopheles coustani (n = 395), Anopheles merus (n = 349), Anopheles pretoriensis (n = 35), Anopheles maculipalpis (n = 28), Anopheles rivulorum (n = 19), Anopheles squamosus (n = 3) and Anopheles rufipes (n = 2). Members of the Anopheles gambiae species complex were the most abundant and widely distributed, occurring across all collection sites. The highest number of mosquitoes was collected using CO2 baited net traps (58.2%) followed by human landing catches (24.8%). Larval collections (17%) provided an additional method to increase sample size. Mosquito sampling productivity was influenced by prevailing weather conditions and overall population densities fluctuated with seasons. Conclusion Several anopheline species occur in the northern Kruger National Park and their densities

  14. Local site effects and dynamic soil behavior

    USGS Publications Warehouse

    Afak, E.

    2001-01-01

    Amplitudes of seismic waves increase significantly as they pass through soft soil layers near the earth's surface. This phenomenon, commonly known as site amplification, is a major factor influencing the extent of damage on structures. It is crucial that site amplification is accounted for when designing structures on soft soils. The characteristics of site amplification at a given site can be estimated by analytical models, as well as field tests. Analytical models require as inputs the geometry of all soil layers from surface to bedrock, their dynamic properties (e.g. density, wave velocity, damping), and the incident bedrock motions. Field tests involve recording and analyzing the dynamic response of sites to artificial excitations, ambient forces, and actual earthquakes. The most reliable estimates of site amplification are obtained by analyzing the recorded motions of the site during strong earthquakes. This paper presents a review of the types and the generating mechanisms of site amplification, and the models and methods that are used to characterize them from earthquake records. ?? 2001 Published by Elsevier Science Ltd.

  15. A rapid, controlled-environment seedling root screen for wheat correlates well with rooting depths at vegetative, but not reproductive, stages at two field sites

    PubMed Central

    Watt, M.; Moosavi, S.; Cunningham, S. C.; Kirkegaard, J. A.; Rebetzke, G. J.; Richards, R. A.

    2013-01-01

    Background and Aims Root length and depth determine capture of water and nutrients by plants, and are targets for crop improvement. Here we assess a controlled-environment wheat seedling screen to determine speed, repeatability and relatedness to performance of young and adult plants in the field. Methods Recombinant inbred lines (RILs) and diverse genotypes were grown in rolled, moist germination paper in growth cabinets, and primary root number and length were measured when leaf 1 or 2 were fully expanded. For comparison, plants were grown in the field and root systems were harvested at the two-leaf stage with either a shovel or a soil core. From about the four-leaf stage, roots were extracted with a steel coring tube only, placed directly over the plant and pushed to the required depth with a hydraulic ram attached to a tractor. Key Results In growth cabinets, repeatability was greatest (r = 0·8, P < 0·01) when the paper was maintained moist and seed weight, pathogens and germination times were controlled. Scanned total root length (slow) was strongly correlated (r = 0·7, P < 0·01) with length of the two longest seminal axile roots measured with a ruler (fast), such that 100–200 genotypes were measured per day. Correlation to field-grown roots at two sites at two leaves was positive and significant within the RILs and cultivars (r = 0·6, P = 0·01), and at one of the two sites at the five-leaf stage within the RILs (r = 0·8, P = 0·05). Measurements made in the field with a shovel or extracted soil cores were fast (5 min per core) and had significant positive correlations to scanner measurements after root washing and cleaning (>2 h per core). Field measurements at two- and five-leaf stages did not correlate with root depth at flowering. Conclusions The seedling screen was fast, repeatable and reliable for selecting lines with greater total root length in the young vegetative phase in the field. Lack of significant correlation with reproductive stage

  16. Evaluation of the Radiochemistry of Near-Field Water Samples at the Nevada Test Site Applied to the Definition of a Hydrologic Source Term

    SciTech Connect

    Smith, D K

    2002-07-05

    Effective management of available groundwater resources and strategies for remediation of water impacted by past nuclear testing practices depend on knowledge about the migration of radionuclides in groundwater away from the sites of the explosions. A primary concern is to assess the relative mobilities of the different radionuclide species found near sites of underground nuclear tests and to determine the concentration, extent, and speed of this movement. Ultimately the long term transport behavior of radionuclides with half-lives long enough that they will persist for decades, their interaction with groundwater, and the resulting flux of these contaminants is of paramount importance. As part of a comprehensive approach to these assessments, more than three decades of site-specific sites studies have been undertaken at the Nevada Test Site (NTS) which have focused on the means responsible for the observed or suspected movement of radionuclides away from underground nuclear tests (RNM, 1983). More recently regional and local models of groundwater flow and radionuclide transport have been developed as part of a federal and state of Nevada program to assess the long-term effects of underground nuclear testing on human health and environment (e.g., U.S. DOE/NV, 1997a; Tompson et al., 1999; Pawloski et al., 2001). Necessary to these efforts is a reliable measure of the hydrologic source term which is defined as those radionuclides dissolved in or otherwise transported by groundwater (Smith et al., 1995). Measurement of radionuclides in waters sampled near the sites of underground nuclear test provides arguably the best opportunity to bound the hydrologic source term. This empirical approach was recognized early and concentration data has been collected annually since mid-1970's. Initially three sites were studied at the NTS; over the years the program has been expanded to include more than fifteen study locations. As part of various field programs, Lawrence Livermore

  17. Possible disruption of remote viewing by complex weak magnetic fields around the stimulus site and the possibility of accessing real phase space: a pilot study.

    PubMed

    Koren, S A; Persinger, M A

    2002-12-01

    In 2002 Persinger, Roll, Tiller, Koren, and Cook considered whether there are physical processes by which recondite information exists within the space and time of objects or events. The stimuli that compose this information might be directly detected within the whole brain without being processed by the typical sensory modalities. We tested the artist Ingo Swann who can reliably draw and describe randomly selected photographs sealed in envelopes in another room. In the present experiment the photographs were immersed continuously in repeated presentations (5 times per sec.) of one of two types of computer-generated complex magnetic field patterns whose intensities were less than 20 nT over most of the area. WINDOWS-generated but not DOS-generated patterns were associated with a marked decrease in Mr. Swann's accuracy. Whereas the DOS software generated exactly the same pattern, WINDOWS software phase-modulated the actual wave form resulting in an infinite bandwidth and complexity. We suggest that information obtained by processes attributed to "paranormal" phenomena have physical correlates that can be masked by weak, infinitely variable magnetic fields.

  18. [Crime scene and criminal findings site of an unknown cadaver in the field: reconstruction based on traces and clinical findings].

    PubMed

    Rittner, C; Ogbuihi, S; Fink, T

    1997-01-01

    The case of a woman with schizophrenia is described who was found dead and nude in a field. To distinguish between a manslaughter, suicide, accident or natural death, details of the scene of death, and the autopsy findings were decisive. In addition, the patient's hospital report was consulted. PMID:9382687

  19. Fast-Turnoff Transient Electromagnetic (TEM) Field Study at the Mars Analog Site of Rio Tinto, Spain

    NASA Astrophysics Data System (ADS)

    Jernsletten, J. A.

    2005-03-01

    This report describes a Fast-Turnoff Transient Electromagnetic (TEM) study at the Peña de Hierro ("Berg of Iron") field area of the Mars Analog Research and Technology Experiment (MARTE), near the towns Rio Tinto and Nerva, Andalucia region, Spain.

  20. Early Field Experiences Offered to and Valued by Preservice Teachers at Sites of Excellence in Reading Teacher Education Programs

    ERIC Educational Resources Information Center

    Sailors, Misty; Keehn, Susan; Martinez, Miriam; Harmon, Janis

    2005-01-01

    The importance of a highly qualified teacher for student learning is undeniably the most important factor in political and research circles today. The question is not "do we need quality teachers?" but "how do we prepare quality teachers?" In this article, we report on the early field experiences offered to preservice teachers at 8 universities…

  1. USE OF FAST GC/TOFMS AS REFERENCE STANDARD FOR FIELD COMPARISON STUDIES WITH ON-SITE INSTRUMENTS

    EPA Science Inventory

    A faster reference standard for field comparison studies of portable gas chromatographs (PGC) is needed. A performance evaluation of a high-speed GCMS (FGC/MS) system conducted during 1998 demonstrated generally satisfactory performance, but it was evident that performance of b...

  2. Genetic variability of spined soldier bugs (Hemiptera: Pentatomidae) sampled from distinct field sites and laboratory colonies in the United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The spined soldier bug, Podisus maculiventris (Say), is an important biological control agent for agricultural and forest pests that preys on eggs and larvae of lepidopteran and coleopteran species. Genetic variability among field collected samples from Michigan, Mississippi, Missouri, and Florida, ...

  3. Experimental evaluation of actual delivered dose using mega-voltage cone-beam CT and direct point dose measurement

    SciTech Connect

    Matsubara, Kana; Kohno, Ryosuke; Nishioka, Shie; Shibuya, Toshiyuki; Ariji, Takaki; Akimoto, Tetsuo; Saitoh, Hidetoshi

    2013-07-01

    Radiation therapy in patients is planned by using computed tomography (CT) images acquired before start of the treatment course. Here, tumor shrinkage or weight loss or both, which are common during the treatment course for patients with head-and-neck (H and N) cancer, causes unexpected differences from the plan, as well as dose uncertainty with the daily positional error of patients. For accurate clinical evaluation, it is essential to identify these anatomical changes and daily positional errors, as well as consequent dosimetric changes. To evaluate the actual delivered dose, the authors proposed direct dose measurement and dose calculation with mega-voltage cone-beam CT (MVCBCT). The purpose of the present study was to experimentally evaluate dose calculation by MVCBCT. Furthermore, actual delivered dose was evaluated directly with accurate phantom setup. Because MVCBCT has CT-number variation, even when the analyzed object has a uniform density, a specific and simple CT-number correction method was developed and applied for the H and N site of a RANDO phantom. Dose distributions were calculated with the corrected MVCBCT images of a cylindrical polymethyl methacrylate phantom. Treatment processes from planning to beam delivery were performed for the H and N site of the RANDO phantom. The image-guided radiation therapy procedure was utilized for the phantom setup to improve measurement reliability. The calculated dose in the RANDO phantom was compared to the measured dose obtained by metal-oxide-semiconductor field-effect transistor detectors. In the polymethyl methacrylate phantom, the calculated and measured doses agreed within about +3%. In the RANDO phantom, the dose difference was less than +5%. The calculated dose based on simulation-CT agreed with the measured dose within±3%, even in the region with a high dose gradient. The actual delivered dose was successfully determined by dose calculation with MVCBCT, and the point dose measurement with the image

  4. Electrokinetic Ion Transport through Unsaturated Soil: 1) Theory, Model Development, and Testing 2) Application to a Heterogeneous Field Site

    SciTech Connect

    Mattson, Earl Douglas; Bowman, R. S.; Lindgren, E. R.

    2002-01-01

    An electromigration transport model for non-reactive ion transport in unsaturated soil was developed and tested against laboratory experiments. This model assumed the electric potential field was constant with respect to time, an assumption valid for highly buffered soil, or when the electrode electrolysis reactions are neutralized. The model also assumed constant moisture contents and temperature with respect to time, and that electroosmotic and hydraulic transport of water through the soil was negligible. A functional relationship between ionic mobility and the electrolyte concentration was estimated using the chemical activity coefficient. Tortuosity was calculated from a mathematical relationship fitted to the electrical conductivity of the bulk pore water and soil moisture data. The functional relationship between ionic mobility, pore-water concentration, and tortuosity as a function of moisture content allowed the model to predict ion transport in heterogeneous unsaturated soils. The model was tested against laboratory measurements assessing anionic electromigration as a function of moisture content. In the test cell, a strip of soil was spiked with red dye No 40 and monitored for a 24-h period while a 10-mA current was maintained between the electrodes. Electromigration velocities predicted by the electromigration transport model were in agreement with laboratory experimental results. Both laboratory-measured and model-predicted dye migration results indicated a maximum transport velocity at moisture contents less than saturation due to competing effects between current density and tortuosity as moisture content decreases. Results of a field demonstration of electrokinetic transport of acetate through an unsaturated heterogeneous soil are compared to numerical modeling predictions. The numerical model was based on the groundwater flow and transport codes MODFLOW and MT3D modified to account for electrically induced ion transport. The 6-month field

  5. Identification of bacteria synthesizing ribosomal RNA in response to uranium addition during biostimulation at the Rifle, CO Integrated Field Research site

    DOE PAGES

    McGuinness, Lora R.; Wilkins, Michael J.; Williams, Kenneth H.; Long, Philip E.; Kerkhof, Lee J.; Boyanov, Maxim I.

    2015-09-18

    Understanding which organisms are capable of reducing uranium at historically contaminated sites provides crucial information needed to evaluate treatment options and outcomes. One approach is determination of the bacteria which directly respond to uranium addition. In this research, uranium amendments were made to groundwater samples from a site of ongoing biostimulation with acetate. The active microbes in the planktonic phase were deduced by monitoring ribosomes production via RT-PCR. The results indicated several microorganisms were synthesizing ribosomes in proportion with uranium amendment up to 2 μM. Concentrations of U (VI) >2 μM were generally found to inhibit ribosome synthesis. Two activemore » bacteria responding to uranium addition in the field were close relatives of Desulfobacter postgateii and Geobacter bemidjiensis. Since RNA content often increases with growth rate, our findings suggest it is possible to rapidly elucidate active bacteria responding to the addition of uranium in field samples and provides a more targeted approach to stimulate specific populations to enhance radionuclide reduction in contaminated sites.« less

  6. Identification of bacteria synthesizing ribosomal RNA in response to uranium addition during biostimulation at the Rifle, CO Integrated Field Research site

    SciTech Connect

    McGuinness, Lora R.; Wilkins, Michael J.; Williams, Kenneth H.; Long, Philip E.; Kerkhof, Lee J.; Boyanov, Maxim I.

    2015-09-18

    Understanding which organisms are capable of reducing uranium at historically contaminated sites provides crucial information needed to evaluate treatment options and outcomes. One approach is determination of the bacteria which directly respond to uranium addition. In this research, uranium amendments were made to groundwater samples from a site of ongoing biostimulation with acetate. The active microbes in the planktonic phase were deduced by monitoring ribosomes production via RT-PCR. The results indicated several microorganisms were synthesizing ribosomes in proportion with uranium amendment up to 2 μM. Concentrations of U (VI) >2 μM were generally found to inhibit ribosome synthesis. Two active bacteria responding to uranium addition in the field were close relatives of Desulfobacter postgateii and Geobacter bemidjiensis. Since RNA content often increases with growth rate, our findings suggest it is possible to rapidly elucidate active bacteria responding to the addition of uranium in field samples and provides a more targeted approach to stimulate specific populations to enhance radionuclide reduction in contaminated sites.

  7. Investigation of Aluminum Site Changes of Dehydrated Zeolite H-Beta during a Rehydration Process by High Field Solid State NMR

    SciTech Connect

    Zhao, Zhenchao; Xu, Suochang; Hu, Mary Y.; Bao, Xinhe; Peden, Charles HF; Hu, Jian Z.

    2015-01-22

    Aluminum site changes for dehydrated H-Beta zeolite during rehydration process are systematically investigated by ²⁷Al MAS and MQ MAS NMR at high magnetic fields up to 19.9 T. Benefiting from the high magnetic field, more detailed information is obtained from the considerably broadened and overlapped spectra of dehydrated H-beta zeolite. Dynamic changes of aluminum sites are demonstrated during rehydration process. In completely dehydrated H-Beta, invisible aluminum can reach 29%. The strength of quadrupole interactions for framework aluminum sites decreases gradually during water adsorption processes. The number of extra-framework aluminum (EFAL) species, i.e., penta- (34 ppm) and octa- (4 ppm) coordinated aluminum atoms rises initially with increasing water adsorption, and finally change into either tetra-coordinated framework or extra-framework aluminum in saturated water adsorption samples, with the remaining octa-coordinated aluminum lying at 0 and -4 ppm, respectively. Quantitative ²⁷Al MAS NMR analysis combined with ¹H MAS NMR indicates that some active EFAL species formed during calcination can reinsert into the framework during this hydration process. The assignment of aluminum at 0 ppm to EFAL cation and -4 ppm to framework aluminum is clarified for H-Beta zeolite.

  8. Identification of Bacteria Synthesizing Ribosomal RNA in Response to Uranium Addition During Biostimulation at the Rifle, CO Integrated Field Research Site.

    PubMed

    McGuinness, Lora R; Wilkins, Michael J; Williams, Kenneth H; Long, Philip E; Kerkhof, Lee J

    2015-01-01

    Understanding which organisms are capable of reducing uranium at historically contaminated sites provides crucial information needed to evaluate treatment options and outcomes. One approach is determination of the bacteria which directly respond to uranium addition. In this study, uranium amendments were made to groundwater samples from a site of ongoing biostimulation with acetate. The active microbes in the planktonic phase were deduced by monitoring ribosomes production via RT-PCR. The results indicated several microorganisms were synthesizing ribosomes in proportion with uranium amendment up to 2 μM. Concentrations of U (VI) >2 μM were generally found to inhibit ribosome synthesis. Two active bacteria responding to uranium addition in the field were close relatives of Desulfobacter postgateii and Geobacter bemidjiensis. Since RNA content often increases with growth rate, our findings suggest it is possible to rapidly elucidate active bacteria responding to the addition of uranium in field samples and provides a more targeted approach to stimulate specific populations to enhance radionuclide reduction in contaminated sites.

  9. Identification of Bacteria Synthesizing Ribosomal RNA in Response to Uranium Addition During Biostimulation at the Rifle, CO Integrated Field Research Site

    PubMed Central

    McGuinness, Lora R.; Wilkins, Michael J.; Williams, Kenneth H.; Long, Philip E.; Kerkhof, Lee J.

    2015-01-01

    Understanding which organisms are capable of reducing uranium at historically contaminated sites provides crucial information needed to evaluate treatment options and outcomes. One approach is determination of the bacteria which directly respond to uranium addition. In this study, uranium amendments were made to groundwater samples from a site of ongoing biostimulation with acetate. The active microbes in the planktonic phase were deduced by monitoring ribosomes production via RT-PCR. The results indicated several microorganisms were synthesizing ribosomes in proportion with uranium amendment up to 2 μM. Concentrations of U (VI) >2 μM were generally found to inhibit ribosome synthesis. Two active bacteria responding to uranium addition in the field were close relatives of Desulfobacter postgateii and Geobacter bemidjiensis. Since RNA content often increases with growth rate, our findings suggest it is possible to rapidly elucidate active bacteria responding to the addition of uranium in field samples and provides a more targeted approach to stimulate specific populations to enhance radionuclide reduction in contaminated sites. PMID:26382047

  10. Identification of Bacteria Synthesizing Ribosomal RNA in Response to Uranium Addition During Biostimulation at the Rifle, CO Integrated Field Research Site.

    PubMed

    McGuinness, Lora R; Wilkins, Michael J; Williams, Kenneth H; Long, Philip E; Kerkhof, Lee J

    2015-01-01

    Understanding which organisms are capable of reducing uranium at historically contaminated sites provides crucial information needed to evaluate treatment options and outcomes. One approach is determination of the bacteria which directly respond to uranium addition. In this study, uranium amendments were made to groundwater samples from a site of ongoing biostimulation with acetate. The active microbes in the planktonic phase were deduced by monitoring ribosomes production via RT-PCR. The results indicated several microorganisms were synthesizing ribosomes in proportion with uranium amendment up to 2 μM. Concentrations of U (VI) >2 μM were generally found to inhibit ribosome synthesis. Two active bacteria responding to uranium addition in the field were close relatives of Desulfobacter postgateii and Geobacter bemidjiensis. Since RNA content often increases with growth rate, our findings suggest it is possible to rapidly elucidate active bacteria responding to the addition of uranium in field samples and provides a more targeted approach to stimulate specific populations to enhance radionuclide reduction in contaminated sites. PMID:26382047

  11. Selection and Characterization of Terrestrial Analogs to the Martian Crust: Field Sites in the U.S. Desert Southwest for Testing Radar Sounders

    NASA Astrophysics Data System (ADS)

    Dinwiddie, C. L.; Stamatakos, J. A.; Gonzalez, S. H.; Grimm, R. E.; McKague, H. L.; Browning, L. B.; Ferrill, D. A.

    2004-05-01

    present available site characterization data, including results of complementary geophysical investigations (e.g., electromagnetic and magnetotelluric) for field locations in the U.S. Desert Southwest that satisfy requirements for suitability as terrestrial analogues to the Martian crust. In particular, we have assembled a wide range of geological, hydrogeological, geophysical, and geochemical data from the vicinity of Yucca Mountain, Nevada. These data have been acquired over the past 15 years as part of our on-going technical work to support the U.S. Nuclear Regulatory Commission in review of a potential license application for a high-level radioactive waste repository. These data make this region of southern Nevada an ideal site for testing existing and planned Martian exploration devices, including radar sounders.

  12. The challenge of modelling nitrogen management at the field scale: simulation and sensitivity analysis of N2O fluxes across nine experimental sites using DailyDayCent

    NASA Astrophysics Data System (ADS)

    Fitton, N.; Datta, A.; Hastings, A.; Kuhnert, M.; Topp, C. F. E.; Cloy, J. M.; Rees, R. M.; Cardenas, L. M.; Williams, J. R.; Smith, K.; Chadwick, D.; Smith, P.

    2014-09-01

    The United Kingdom currently reports nitrous oxide emissions from agriculture using the IPCC default Tier 1 methodology. However Tier 1 estimates have a large degree of uncertainty as they do not account for spatial variations in emissions. Therefore biogeochemical models such as DailyDayCent (DDC) are increasingly being used to provide a spatially disaggregated assessment of annual emissions. Prior to use, an assessment of the ability of the model to predict annual emissions should be undertaken, coupled with an analysis of how model inputs influence model outputs, and whether the modelled estimates are more robust that those derived from the Tier 1 methodology. The aims of the study were (a) to evaluate if the DailyDayCent model can accurately estimate annual N2O emissions across nine different experimental sites, (b) to examine its sensitivity to different soil and climate inputs across a number of experimental sites and (c) to examine the influence of uncertainty in the measured inputs on modelled N2O emissions. DailyDayCent performed well across the range of cropland and grassland sites, particularly for fertilized fields indicating that it is robust for UK conditions. The sensitivity of the model varied across the sites and also between fertilizer/manure treatments. Overall our results showed that there was a stronger correlation between the sensitivity of N2O emissions to changes in soil pH and clay content than the remaining input parameters used in this study. The lower the initial site values for soil pH and clay content, the more sensitive DDC was to changes from their initial value. When we compared modelled estimates with Tier 1 estimates for each site, we found that DailyDayCent provided a more accurate representation of the rate of annual emissions.

  13. The synergistic use of models and observations: understanding the mechanisms behind observed biomass dynamics at 14 Amazonian field sites and the implications for future biomass change

    NASA Astrophysics Data System (ADS)

    Levine, N. M.; Galbraith, D.; Christoffersen, B. J.; Imbuzeiro, H. A.; Restrepo-Coupe, N.; Malhi, Y.; Saleska, S. R.; Costa, M. H.; Phillips, O.; Andrade, A.; Moorcroft, P. R.

    2011-12-01

    The Amazonian rainforests play a vital role in global water, energy and carbon cycling. The sensitivity of this system to natural and anthropogenic disturbances therefore has important implications for the global climate. Some global models have predicted large-scale forest dieback and the savannization of Amazonia over the next century [Meehl et al., 2007]. While several studies have demonstrated the sensitivity of dynamic global vegetation models to changes in temperature, precipitation, and dry season length [e.g. Galbraith et al., 2010; Good et al., 2011], the ability of these models to accurately reproduce ecosystem dynamics of present-day transitional or low biomass tropical forests has not been demonstrated. A model-data intercomparison was conducted with four state-of-the-art terrestrial ecosystem models to evaluate the ability of these models to accurately represent structure, function, and long-term biomass dynamics over a range of Amazonian ecosystems. Each modeling group conducted a series of simulations for 14 sites including mature forest, transitional forest, savannah, and agricultural/pasture sites. All models were run using standard physical parameters and the same initialization procedure. Model results were compared against forest inventory and dendrometer data in addition to flux tower measurements. While the models compared well against field observations for the mature forest sites, significant differences were observed between predicted and measured ecosystem structure and dynamics for the transitional forest and savannah sites. The length of the dry season and soil sand content were good predictors of model performance. In addition, for the big leaf models, model performance was highest for sites dominated by late successional trees and lowest for sites with predominantly early and mid-successional trees. This study provides insight into tropical forest function and sensitivity to environmental conditions that will aid in predictions of the

  14. Charge-regulation phase transition on surface lattices of titratable sites adjacent to electrolyte solutions: An analog of the Ising antiferromagnet in a magnetic field

    NASA Astrophysics Data System (ADS)

    Shore, Joel D.; Thurston, George M.

    2015-12-01

    We report a charge-patterning phase transition on two-dimensional square lattices of titratable sites, here regarded as protonation sites, placed in a low-dielectric medium just below the planar interface between this medium and a salt solution. We calculate the work-of-charging matrix of the lattice with use of a linear Debye-Hückel model, as input to a grand-canonical partition function for the distribution of occupancy patterns. For a large range of parameter values, this model exhibits an approximate inverse cubic power-law decrease of the voltage produced by an individual charge, as a function of its in-lattice separation from neighboring titratable sites. Thus, the charge coupling voltage biases the local probabilities of proton binding as a function of the occupancy of sites for many neighbors beyond the nearest ones. We find that even in the presence of these longer-range interactions, the site couplings give rise to a phase transition in which the site occupancies exhibit an alternating, checkerboard pattern that is an analog of antiferromagnetic ordering. The overall strength W of this canonical charge coupling voltage, per unit charge, is a function of the Debye length, the charge depth, the Bjerrum length, and the dielectric coefficients of the medium and the solvent. The alternating occupancy transition occurs above a curve of thermodynamic critical points in the (p H-p K ,W ) plane, the curve representing a charge-regulation analog of variation of the Néel temperature of an Ising antiferromagnet as a function of an applied, uniform magnetic field. The analog of a uniform magnetic field in the antiferromagnet problem is a combination of p H-p K and W , and 1 /W is the analog of the temperature in the antiferromagnet problem. We use Monte Carlo simulations to study the occupancy patterns of the titratable sites, including interactions out to the 37th nearest-neighbor category (a distance of √{74 } lattice constants), first validating simulations

  15. Actual problems of research in food science.

    PubMed

    Schmandke, H

    1981-01-01

    Starting from the necessary trend towards development in the field of food production, the author outlines, on the basis of current knowledge, the problems to be solved in food science. A general research conception is deduced for the essential nutrient "protein" (as an example) which is illustrated by results from studies on protein fibre and protein gel formation.

  16. Isolating the actual signal of paleointensity?

    NASA Astrophysics Data System (ADS)

    Valet, J. M.; Moreno, E.; Bassinot, F.; Herrero-Bervera, E.

    2011-12-01

    Signals of relative and absolute paleointensity suffer inaccuracies and contaminations that must be considered to improve our knowledge of the field variations. Climatically related changes in rock magnetic parameters are frequently suspected of influencing the signal of relative paleointensity extrated from marine sediments. High resolution measurements of climatic and magnetic parameters have been performed on two cores from the eastern China Sea and the western Caroline Basin. On both cores, magnetic parameters show a strong imprint of climatic changes but the absence of relationship between the inclination and the bulk density indicates that the directional changes do not depend on lithology. All normalization parameters yielded similar estimates of relative paleointensity (RPI), but we have noticed the persistence of climatic components in the signal. Principal Component Analysis (PCA) applied to different parameters related to climate, lithology and paleointensity has allowed to extract a "clean" magnetic signal that we refer as "principal component of paleointensity (PCP)" which is in better agreement with the Sint-2000 composite curve and provides a reliable record of relative paleointensity. The presence of climatic frequencies in RPIs most likely reflects the influence of lithology on the response of magnetization to field intensity. We suggest that PCA analysis can be very useful to approach these problems. Not only can the calculation separate overlapping climatic and magnetic signals, but it indicates what confidence should be given to the data. Incidentally, the present results emphasize the importance of carrying out detailed paleoclimatic analyses along with paleointensity studies. Many approaches have been proposed during the past 20 years for experiments of absolute paleointensity in order to reduce the duration of the experiments and increase the number of field determinations. However, this is frequently obtained to the detriment of the accuracy

  17. Characterization of the geochemical and physical properties of wetland soils on the Savannah River Site: Field sampling activities. Final report

    SciTech Connect

    Dixon, K.L.

    1992-11-01

    There are 36,000 acres of wetlands on the Savannah River Site (SRS) and an additional 5,000 acres of floodplain. Recent studies of wetland soils near various waste sites at SRS have shown that some wetlands have been contaminated with pollutants resulting from SRS operations. In general, releases of contaminants to wetland areas have been indirect. These releases may have originated at disposal lagoons or waste facilities located in the vicinity of the wetland areas. Transport mechanisms such as surface runoff, soil erosion, sediment transport, and groundwater seepage into downgradient wetland areas are responsible for the indirect discharges to the wetland areas. The SRS determined that a database of background geochemical and physical properties for wetland soils on the SRS was needed to facilitate future remedial investigations, human health and ecological risk assessments, treatability studies, and feasibility studies for the wetland areas. These data are needed for comparison to contaminant data collected from wetland soils that have been affected by contamination from SRS operations. This report describes the efforts associated with the collection of soil cores, preparation of a lithologic log for each core, and the processing and packaging of individual soil samples for shipment to analytical laboratory facilities.

  18. Characterization of the geochemical and physical properties of wetland soils on the Savannah River Site: Field sampling activities

    SciTech Connect

    Dixon, K.L. )

    1992-11-01

    There are 36,000 acres of wetlands on the Savannah River Site (SRS) and an additional 5,000 acres of floodplain. Recent studies of wetland soils near various waste sites at SRS have shown that some wetlands have been contaminated with pollutants resulting from SRS operations. In general, releases of contaminants to wetland areas have been indirect. These releases may have originated at disposal lagoons or waste facilities located in the vicinity of the wetland areas. Transport mechanisms such as surface runoff, soil erosion, sediment transport, and groundwater seepage into downgradient wetland areas are responsible for the indirect discharges to the wetland areas. The SRS determined that a database of background geochemical and physical properties for wetland soils on the SRS was needed to facilitate future remedial investigations, human health and ecological risk assessments, treatability studies, and feasibility studies for the wetland areas. These data are needed for comparison to contaminant data collected from wetland soils that have been affected by contamination from SRS operations. This report describes the efforts associated with the collection of soil cores, preparation of a lithologic log for each core, and the processing and packaging of individual soil samples for shipment to analytical laboratory facilities.

  19. Web and Web Services based tool that provides Subsets and Visualization of MODIS land products to facilitate land validation and field site characterization

    NASA Astrophysics Data System (ADS)

    Santhana Vannan, S.; Cook, R. B.; Wilson, B. E.

    2009-12-01

    The MODIS (Moderate Resolution Imaging Spectroradiometer) sensor data are highly useful for field research. The spectral, spatial and temporal characteristics of MODIS products have made them an important data source for analyzing key science questions relating to Earth System processes at regional, continental, and global scales. MODIS data are particularly useful to validate and inter-compare ground measurements at various field sites such as flux tower locations. MODIS data are also useful in land validation and in understanding biogeochemical and ecological processes. However, MODIS data volume and the complexity in data format makes MODIS data less usable in some cases. To solve this usability issue, the Oak Ridge National Laboratory (ORNL) Distributed Active Archive Center (DAAC) has developed a system that prepares and distributes subsets of selected MODIS Land Products in a scale and format useful for field researchers. The MODIS subsets are provided for more than 1,000 sites across the globe. Most of the eddy covariance flux tower sites are included in the site list. The subsets are offered in tabular ASCII format and in GIS compatible GeoTIFF format. Time series plots and grid visualizations to help characterize field sites are also provided. The MODIS fixed site subsets and the various visualizations can be accessed from http://daac.ornl.gov/modisfixedsite In addition to offering subsets for fixed sites, the ORNL DAAC also offers the capability to create user-defined subsets for any location worldwide. The MODIS Global subsetting tool provides subsets from a single pixel up to 201 x 201 km for user-defined time range. Statistics, time series plots, stacked time series plots for inter-annual comparison and GIS compatible files for the customized subsets are also distributed through this tool. Users place an order for a MODIS subset online and an email is generated when the subset is created. To create subsets for any location around the globe use http

  20. Consequences of Predicted or Actual Asteroid Impacts

    NASA Astrophysics Data System (ADS)

    Chapman, C. R.

    2003-12-01

    Earth impact by an asteroid could have enormous physical and environmental consequences. Impactors larger than 2 km diameter could be so destructive as to threaten civilization. Since such events greatly exceed any other natural or man-made catastrophe, much extrapolation is necessary just to understand environmental implications (e.g. sudden global cooling, tsunami magnitude, toxic effects). Responses of vital elements of the ecosystem (e.g. agriculture) and of human society to such an impact are conjectural. For instance, response to the Blackout of 2003 was restrained, but response to 9/11 terrorism was arguably exaggerated and dysfunctional; would society be fragile or robust in the face of global catastrophe? Even small impacts, or predictions of impacts (accurate or faulty), could generate disproportionate responses, especially if news media reports are hyped or inaccurate or if responsible entities (e.g. military organizations in regions of conflict) are inadequately aware of the phenomenology of small impacts. Asteroid impact is the one geophysical hazard of high potential consequence with which we, fortunately, have essentially no historical experience. It is thus important that decision makers familiarize themselves with the hazard and that society (perhaps using a formal procedure, like a National Academy of Sciences study) evaluate the priority of addressing the hazard by (a) further telescopic searches for dangerous but still-undiscovered asteroids and (b) development of mitigation strategies (including deflection of an oncoming asteroid and on- Earth civil defense). I exemplify these issues by discussing several representative cases that span the range of parameters. Many of the specific physical consequences of impact involve effects like those of other geophysical disasters (flood, fire, earthquake, etc.), but the psychological and sociological aspects of predicted and actual impacts are distinctive. Standard economic cost/benefit analyses may not

  1. Distribution and geochemical characterization of coalbed gases at excavation fields at natural analogue site area Velenje Basin, Slovenia

    NASA Astrophysics Data System (ADS)

    Kanduč, Tjaša; Žigon, Stojan; Grassa, Fausto; Sedlar, Jerneja; Zadnik, Ivo; Zavšek, Simon

    2016-04-01

    Unconventional gas resources, including coal bed methane and shale gas, are a growing part of the global energy mix, which has changed the economic and strategic picture for gas consuming and producing countries, including the USA, China and Australia that, together are responsible for around half the currently recoverable unconventional gas resources. However, CBM production was often hindered by low permeability and mineralization in cleats and fractures, necessitating the development of cost effective horizontal drilling and completion techniques. Geochemical and isotopic monitoring of coalbed gases at excavation fields in Velenje Basin started in year 2000, with the aim to obtain better insights into the origin of coalbed gases. Results from active excavation fields in the mining areas Pesje and Preloge in the year period 2014-2015 are presented in this study. Composition and isotopic composition of coalbed gases were determined with mass - spectrometric methods. The chemical (methane, carbon dioxide, nitrogen) and isotopic composition of carbon in methane and carbon dioxide in the Velenje Basin vary and depend on the composition of the source of coalbed gas before excavation, advancement of the working face, depth of the longwall face, pre-mining activity and newly mined activity. The basic gas components determined in excavation fields are carbon dioxide and methane. Knowledge of the stable isotope geochemistry of coal bed and shale gas and the related production water is essential to determine not only gas origins but also the dominant methanogenic pathway in the case of microbial gas. Concentrations of methane at active excavation fields are changing from 1.8 to 63.9 %, concentrations of carbon dioxide are changing from 36.1 to 98.2% and CDMI (Carbon Dioxide Methane Index) index from 0.2 to 100 %. Isotopic composition of carbon dioxide is changing from -11.0 to -1.9‰ , isotopic composition of methane from -71.8 to -43.3‰ , isotopic composition of

  2. Crystal-field energy level analysis for Nd(3+) ions at the low symmetry C(1) site in [Nd(hfa)(4)(H(2)O)](N(C(2)H(5))(4)) single crystals.

    PubMed

    Mech, Agnieszka; Gajek, Zbigniew; Karbowiak, Mirosław; Rudowicz, Czesław

    2008-09-24

    Optical absorption measurements of Nd(3+) ions in single crystals of [Nd(hfa)(4)(H(2)O)](N(C(2)H(5))(4)) (hfa = hexafluoroacetyloacetonate), denoted Nd(hfa) for short, have been carried out at 4.2 and 298 K. This compound crystallizes in the monoclinic system (space group P 2(1)/n). Each Nd ion is coordinated to eight oxygen atoms that originate from the hexafluoroacetylacetonate ligands and one oxygen atom from the water molecule. A total of 85 experimental crystal-field (CF) energy levels arising from the Nd(3+) (4f(3)) electronic configuration were identified in the optical spectra and assigned. A three-step CF analysis was carried out in terms of a parametric Hamiltonian for the actual C(1) symmetry at the Nd(3+) ion sites. In the first step, a total of 27 CF parameters (CFPs) in the Wybourne notation B(kq), admissible by group theory, were determined in a preliminary fitting constrained by the angular overlap model predictions. The resulting CFP set was reduced to 24 specific independent CFPs using appropriate standardization transformations. Optimizations of the second-rank CFPs and extended scanning of the parameter space were employed in the second step to improve reliability of the CFP sets, which is rather a difficult task in the case of no site symmetry. Finally, seven free-ion parameters and 24 CFPs were freely varied, yielding an rms deviation between the calculated energy levels and the 85 observed ones of 11.1 cm(-1). Our approach also allows prediction of the energy levels of Nd(3+) ions that are hidden in the spectral range overlapping with strong ligand absorption, which is essential for understanding the inter-ionic energy transfer. The orientation of the axis system associated with the fitted CF parameters w.r.t. the crystallographic axes is established. The procedure adopted in our calculations may be considered as a general framework for analysis of CF levels of lanthanide ions at low (triclinic) symmetry sites.

  3. WIPP site and vicinity geological field trip. A report of a field trip to the proposed Waste Isolation Pilot Plant project in Southeastern New Mexico, June 16 to 18, 1980

    SciTech Connect

    Chaturvedi, L

    1980-10-01

    The Environmental Evaluation Group is conducting an assessment of the radiological health risks to people from the Waste Isolation Pilot Plant. As a part of this work, EEG is making an effort to improve the understanding of those geological issues concerning the WIPP site which may affect the radiological consequences of the proposed repository. One of the important geological issues to be resolved is the timing and the nature of the dissolution processes which may have affected the WIPP site. EEG organized a two-day conference of geological scientists, on January 17-18, 1980. On the basis of the January conference and the June field trip, EEG has formed the following conclusions: (1) it has not been clearly established that the site or the surrounding area has been attacked by deep dissolution to render it unsuitable for the nuclear waste pilot repository; (2) the existence of an isolated breccia pipe at the site unaccompanied by a deep dissolution wedge, is a very remote possibility; (3) more specific information about the origin and the nature of the brine reservoirs is needed. An important question that should be resolved is whether each encounter with artesian brine represents a separate pocket or whether these occurrences are interconnected; (4) Anderson has postulated a major tectonic fault or a fracture system at the Basin margin along the San Simon Swale; (5) the area in the northern part of the WIPP site, identified from geophysical and bore hole data as the disturbed zone, should be further investigated to cleary understand the nature and significance of this structural anomaly; and (6) a major drawback encountered during the discussions of geological issues related to the WIPP site is the absence of published material that brings together all the known information related to a particular issue.

  4. [Tuberculosis: actual problems with diagnosis and treatment].

    PubMed

    Korzeniewska-Koseła, Maria

    2016-01-01

    Tuberculosis (TB) is an infectious disease caused by Mycobacterium tuberculosis complex. It remains health problem also in developed countries. Most common form of tuberculosis is pulmonary disease but other sites of the body can be affected (extrapulmonary TB). As TB incidence falls, the probability of developing active diseases in people infected with M. tuberculosis is higher among imunocompromised people and in people from risk groups. People who present with unexplained cough lasting two or more weeks or with findings suggestive of tuberculosis on chest radiographs should be evaluated for tuberculosis. For patients suspected of having pulmonary or extrapulmonary tuberculosis specimens from the sites of involvement should be obtained for microbiological tests. Bronchoscopy and BAL should be performed in patients that do not produce sputum and with negative sputum smears. Ct scan may also play an important role in the evaluation of patients suspected of having TB but with negative sputum smears. The standard therapy for TB should consist of two months of isoniazid, rifampicin, pyrazinamide, and ethambutol in the initial phase and of isoniazid and rifampicin given for 4 months (the continuation phase). PMID:27421129

  5. Binding Site Alteration Is Responsible for Field-Isolated Resistance to Bacillus thuringiensis Cry2A Insecticidal Proteins in Two Helicoverpa Species

    PubMed Central

    Caccia, Silvia; Hernández-Rodríguez, Carmen Sara; Mahon, Rod J.; Downes, Sharon; James, William; Bautsoens, Nadine; Van Rie, Jeroen; Ferré, Juan

    2010-01-01

    Background Evolution of resistance by target pests is the main threat to the long-term efficacy of crops expressing Bacillus thuringiensis (Bt) insecticidal proteins. Cry2 proteins play a pivotal role in current Bt spray formulations and transgenic crops and they complement Cry1A proteins because of their different mode of action. Their presence is critical in the control of those lepidopteran species, such as Helicoverpa spp., which are not highly susceptible to Cry1A proteins. In Australia, a transgenic variety of cotton expressing Cry1Ac and Cry2Ab (Bollgard II) comprises at least 80% of the total cotton area. Prior to the widespread adoption of Bollgard II, the frequency of alleles conferring resistance to Cry2Ab in field populations of Helicoverpa armigera and Helicoverpa punctigera was significantly higher than anticipated. Colonies established from survivors of F2 screens against Cry2Ab are highly resistant to this toxin, but susceptible to Cry1Ac. Methodology/Principal Findings Bioassays performed with surface-treated artificial diet on neonates of H. armigera and H. punctigera showed that Cry2Ab resistant insects were cross-resistant to Cry2Ae while susceptible to Cry1Ab. Binding analyses with 125I-labeled Cry2Ab were performed with brush border membrane vesicles from midguts of Cry2Ab susceptible and resistant insects. The results of the binding analyses correlated with bioassay data and demonstrated that resistant insects exhibited greatly reduced binding of Cry2Ab toxin to midgut receptors, whereas no change in 125I-labeled-Cry1Ac binding was detected. As previously demonstrated for H. armigera, Cry2Ab binding sites in H. punctigera were shown to be shared by Cry2Ae, which explains why an alteration of the shared binding site would lead to cross-resistance between the two Cry2A toxins. Conclusion/Significance This is the first time that a mechanism of resistance to the Cry2 class of insecticidal proteins has been reported. Because we found the same

  6. mHealth Series: mHealth project in Zhao County, rural China – Description of objectives, field site and methods

    PubMed Central

    van Velthoven, Michelle Helena; Li, Ye; Wang, Wei; Du, Xiaozhen; Wu, Qiong; Chen, Li; Majeed, Azeem; Rudan, Igor; Zhang, Yanfeng; Car, Josip

    2013-01-01

    Background We set up a collaboration between researchers in China and the UK that aimed to explore the use of mHealth in China. This is the first paper in a series of papers on a large mHealth project part of this collaboration. This paper included the aims and objectives of the mHealth project, our field site, and the detailed methods of two studies. Field site The field site for this mHealth project was Zhao County, which lies 280 km south of Beijing in Hebei Province, China. Methods We described the methodology of two studies: (i) a mixed methods study exploring factors influencing sample size calculations for mHealth–based health surveys and (ii) a cross–over study determining validity of an mHealth text messaging data collection tool. The first study used mixed methods, both quantitative and qualitative, including: (i) two surveys with caregivers of young children, (ii) interviews with caregivers, village doctors and participants of the cross–over study, and (iii) researchers’ views. We combined data from caregivers, village doctors and researchers to provide an in–depth understanding of factors influencing sample size calculations for mHealth–based health surveys. The second study, a cross–over study, used a randomised cross–over study design to compare the traditional face–to–face survey method to the new text messaging survey method. We assessed data equivalence (intrarater agreement), the amount of information in responses, reasons for giving different responses, the response rate, characteristics of non–responders, and the error rate. Conclusions This paper described the objectives, field site and methods of a large mHealth project part of a collaboration between researchers in China and the UK. The mixed methods study evaluating factors that influence sample size calculations could help future studies with estimating reliable sample sizes. The cross–over study comparing face–to–face and text message survey data collection

  7. Predicting Scenarios for Successful Autodissemination of Pyriproxyfen by Malaria Vectors from Their Resting Sites to Aquatic Habitats; Description and Simulation Analysis of a Field-Parameterizable Model

    PubMed Central

    Kiware, Samson S.; Corliss, George; Merrill, Stephen; Lwetoijera, Dickson W.; Devine, Gregor; Majambere, Silas; Killeen, Gerry F.

    2015-01-01

    Background Large-cage experiments indicate pyriproxifen (PPF) can be transferred from resting sites to aquatic habitats by Anopheles arabiensis - malaria vector mosquitoes to inhibit emergence of their own offspring. PPF coverage is amplified twice: (1) partial coverage of resting sites with PPF contamination results in far higher contamination coverage of adult mosquitoes because they are mobile and use numerous resting sites per gonotrophic cycle, and (2) even greater contamination coverage of aquatic habitats results from accumulation of PPF from multiple oviposition events. Methods and Findings Deterministic mathematical models are described that use only field-measurable input parameters and capture the biological processes that mediate PPF autodissemination. Recent successes in large cages can be rationalized, and the plausibility of success under full field conditions can be evaluated a priori. The model also defines measurable properties of PPF delivery prototypes that may be optimized under controlled experimental conditions to maximize chances of success in full field trials. The most obvious flaw in this model is the endogenous relationship that inevitably occurs between the larval habitat coverage and the measured rate of oviposition into those habitats if the target mosquito species is used to mediate PPF transfer. However, this inconsistency also illustrates the potential advantages of using a different, non-target mosquito species for contamination at selected resting sites that shares the same aquatic habitats as the primary target. For autodissemination interventions to eliminate malaria transmission or vector populations during the dry season window of opportunity will require comprehensive contamination of the most challenging subset of aquatic habitats (Clx) that persist or retain PPF activity (Ux) for only one week (Clx→1, where Ux = 7 days). To achieve >99% contamination coverage of these habitats will necessitate values for the product of

  8. CO2 leakage impacts on shallow groundwater. Field-scale reactive-transport simulations informed by observations at a natural analog site

    DOE PAGES

    Keating, Elizabeth H.; Hakala, J. Alexandra; Viswanathan, Hari; Carey, J. William; Pawar, Rajesh; Guthrie, George D.; Fessenden-Rahn, Julianna

    2013-03-01

    It is challenging to predict the degree to which shallow groundwater might be affected by leaks from a CO2 sequestration reservoir, particularly over long time scales and large spatial scales. In this study observations at a CO2 enriched shallow aquifer natural analog were used to develop a predictive model which is then used to simulate leakage scenarios. This natural analog provides the opportunity to make direct field observations of groundwater chemistry in the presence of elevated CO2, to collect aquifer samples and expose them to CO2 under controlled conditions in the laboratory, and to test the ability of multiphase reactivemore » transport models to reproduce measured geochemical trends at the field-scale. The field observations suggest that brackish water entrained with the upwelling CO2 are a more significant source of trace metals than in situ mobilization of metals due to exposure to CO2. The study focuses on a single trace metal of concern at this site: U. Experimental results indicate that cation exchange/adsorption and dissolution/precipitation of calcite containing trace amounts of U are important reactions controlling U in groundwater at this site, and that the amount of U associated with calcite is fairly well constrained. Simulations incorporating these results into a 3-D multi-phase reactive transport model are able to reproduce the measured ranges and trends between pH, pCO2, Ca, total C, U and Cl-at the field site. Although the true fluxes at the natural analog site are unknown, the cumulative CO2 flux inferred from these simulations are approximately equivalent to 37.8E-3 MT, approximately corresponding to a .001% leak rate for injection at a large (750 MW) power plant. The leakage scenario simulations suggest that if the leak only persists for a short time the volume of aquifer contaminated by CO2-induced mobilization of U will be relatively small, yet persistent over 100 a.« less

  9. CO2 leakage impacts on shallow groundwater. Field-scale reactive-transport simulations informed by observations at a natural analog